[antigenic analysis and immunological studies of the uterotropic bacterial strains sh6 and 01 isolated from aborted cows].the uterotropic strains sh6 and o1 were studied immunoelectrophoretically to establish their antigenic relationship. the more readily diffusing component of the o-antigenic fraction of the strains proved immunologically identical with lpa of the r brucella organisms, while the slower component showed common determinants with the o-antigenic fraction of yersinia pseudotuberculosis. immunodiffusion revealed that the o-antigenic fraction of the o1 strain and lpa of the s brucella organisms contain ...197660821
whole-blood lymphocyte stimulation assay for measurement of cell-mediated immune responses in bovine brucellosis.a study was conducted to develop an in vitro whole-blood lymphocyte stimulation assay for measurement of cell-mediated immune response in bovine brucellosis. a soluble antigen (basa) prepared from killed cells of brucella abortus 1119-3 was used. cattle infected with b. abortus field strains, b. abortus 19 calfhood- and adult-vaccinated cattle, and nonexposed cattle were tested. blood was diluted 10-fold in rpmi-1640 medium (without added serum) and cultured with basa (at a concentration of 2.2 ...197897304
comparison of sensitivity and specificity of purified lymphocyte and whole-blood in vitro lymphocyte stimulation assays in detection of brucella abortus infection in cattle.a study was conducted to compare the sensitivity and specificity of purified lymphocyte and whole-blood in vitro lymphocyte stimulation assays in detection of brucella abortus infection in cattle. cattle used were infected with b. abortus field strains or strain 19. peripheral blood was collected, and lymphocytes for the technique. the blood for the whole-blood lymphocyte stimulation assay was diluted 10-fold with rpmi 1640 medium (without additional serum supplement) and cultured. the two tests ...1978102656
a solid-phase radioimmunoassay for the determination of bacterial-specific antibodies within different immunoglobulin classes: application to bovine brucella abortus antibodies.a solid-phase radioimmunoassay (ria) has been developed for quantitation of class-specific antibodies against bacteria. brucella abortus cells were used to sensitize glass tubes after sedimentation, drying and methanol fixation. bovine antibodies that attached to the bacteria were detected by binding of a rabbit antiserum specific for each class or subclass of bovine immunoglobulins followed by binding of 125i sheep anti-rabbit immunoglobulin reagent. this three-step method was adapted as it was ...1978107846
the effects of brucella abortus on serology, bacteriology, and production in three texas cattle herds. 1978109847
evaluation of the enzyme-linked immunosorbent assay for detecting brucella abortus antibodies.the specificity of enzyme-linked immunosorbent assays (elisa) corresponds to conventional methods for detecting brucella antibodies in bovine serum. the elisa test detected brucella antibodies early in only 12.5% of the cattle sera tested. also, the sensitivity of elisa was comparable to complement-fixation and rivanol methods, but less sensitive than the standard tube agglutination method.1979112893
effect of halothane anaesthesia on primary antibody response in the chicken.the effect of a single anaesthesia of 2 hours' duration with 1% v/v halothane and of 1, 2, and 3 hours' duration with 2% v/v halothane was studied on the primary antibody response in line-bred chickens. in contradistinction to earlier studies, the immunisation was performed during anaesthesia to resemble antigenic exposure in surgical practice. the igg and igm antibodies against the antigens, bovine serum albumin (bsa) and formalin-killed brucella abortus organisms (brucella), were quantified by ...1979115219
comparison of serological methods for the detection of b. abortus antibodies in sera from vaccinated and non-vaccinated cattle.a total of 4551 sera from 863 strain 19 vaccinated and non-vaccinated adult cattle, independent of disease status, were tested by five serological methods to detect the presence of antibodies to b. abortus. results from standard agglutination tube (sat), buffered brucella antigen or card (ct), complement fixation (cf), enzyme linked immunosorbent assay (elisa) and rivanol (riv) methods were compared. there was a 95% probability for agreement among ct negative sera, between serological methods, f ...1979117051
effects of cyclophosphamide on the lymphoid tissues and humoral and cellular immune responsiveness of young calves.cyclophosphamide (cy) was given iv to 5-month-old calves (ten doses; each dose of 5.0 mg/kg, 2-day intervals between doses). the effects of cy on circulating leukocytes, lymphoid tissues, and the humoral and cellular immune responses were assessed. the numbers of total leukocytes, lymphocytes, and neutrophils and platelets decreased significantly. the lymphocyte population was depleted in the cortex of the thymus and b-dependent areas of the spleen and lymph nodes. significant decreases occurred ...1979118689
persistence of brucella abortus infection in six herds of cattle under brucellosis eradication. 1979119934
immunological responses of fluke-infected and fluke-free cattle to salmonella dublin and other antigens.immune responses to heat-killed brucella abortus strain 19 and to ovalbumin were compared in 15 fluke-infected and 15 fluke-free friesian heifers. b abortus was injected 16 weeks and ovalbumin 19 weeks after the oral administration of 1000 metacercariae of fasciola hepatica. agglutinating antibody responses to b abortus were similar in both groups. immediate type hypersensitivity to ovalbumin was apparently suppressed in fluke-infected animals when assessed by active and passive cutaneous anaphy ...1979120572
the bovine immune response to brucella abortus. ii. elimination of some sporadic serological reactions by chelation of divalent cations.the standard agglutination tests for detecting antibody to brucella abortus were modified by addition of chelating agents (edta and egta) to the antigens. approximately 80% of "singleton" agglutination test reactions, negative on the diagnostic complement fixation test, obtained with cattle sera were eliminated while no decrease in titer was apparent when sera from b. abortus infected or vaccinated cattle were tested.1979121242
a serologic survey of pronghorns in alberta and saskatchewan, determine the exposure of free-ranging pronghorns (antilocapra americana ord) to selected pathogens, serum samples were obtained from 33 live-trapped animals from southwestern saskatchewan in 1970, and from 26 and 51 animals from southeastern alberta, in 1971 and 1972, respectively. antibodies were found to the agents of parainfluenza 3, bovine virus diarrhea, eastern and western encephalomyelitis, infectious bovine rhinotracheitis and the chlamydial group. no serologic reactors were found to ...1975167203
some effects of silical treatment on marek's disease.treatment of newly hatched chicks with silica by the intraperitoneal route delayed the onset of mortalities due to the jm strain of marek's disease (md' virus inoculated at 6 days of age. during the 88-day observation period fewer silica-treated chicks died of md, but this difference was not usually statistically significant. silica treatment had no effect on the susceptibility of 4-week-old birds. silica treatment reduced the antibody response to md but, in general, not significantly. the antib ...1976179947
[combined vaccines including 1 or several anti-foot-and-mouth valences].combined vaccines are used for many human and animal diseases. however, we have very few examples of combinations containing anti-foot-and-mouth valence which would allow easy immunization against differnet diseases without additional handling. until now foot-and-mouth vaccination has been applied simultaneously with anti-brucellic vaccination (baldoni, renoux), andi-anthrax (nobili) and vaccination against swine fever and aujeszky's disease (lysenko). during the last ten years we have particul ...1976198308
trends of brucellosis in florida. an epidemiologic review.human brucellosis in florida is documented for the 47-year period 1928-1975. of the 936 cases reported in 1930-1975, more than half (505) occurred in the decade 1940-1949. the incidence declined rapidly to an average rate of five cases per year, although there was an increase in 1974 and 1975. the analysis is mainly concerned with the years 1961-1975, since more complete epidemiologic data are available for this period. cases occurred throughout the year, with the highest incidence being between ...1977403760
the effects of igg2 and of antigen concentration on prozoning in the complement fixation test for bovine brucellosis.addition of brucella-specific igg2 to solutions of brucella-specific igg1 initially induced prozoning and at higher concentrations prevented all reaction in the complement fixation test (cft) for bovine brucellosis. some infected cattle may be diagnosed as brucellosis-free due to a high ratio of specific igg2 to igg1. increasing the concentration of antigen in the cft reduced the tendency to prozone.1977404679
application of the indirect enzyme-labeled antibody microtest to the detection and surveillance of animal diseases.the rapid, indirect enzyme-labeled antibody (ela) microplate test has been developed as a diagnostic and surveillance tool to aid in the control of animal disease. the test has been applied to viral (hog cholera), parasitic (trichinosis), and bacterial (brucellosis) diseases of animals. a correlation of greater than 95% was observed between the hog cholera ela test and the serum neutralization test for hog cholera in greater than 2,000 field samples obtained during the 1976 epizootic in new jers ...1977409789
[allergic diagnosis of bovine brucellosis. 1. conditions for the use of a purified protein allergen: brucellin (author's transl)].a protein allergen extracted from the rough strain brucella melitensis b 115, prepared for the diagnosis of brucellosis, has been evaluated in cows. injected in non infected and non vaccinated cows, this allergen does not give any reaction, does not sensitize for subsequent injections, does not give rise to antibodies detected by routine serologic tests, and thus does not interfere with usual screening. in cows, sensitized by injections of h 38 or 45/20 vaccines, the intradermal injection produc ...1977413466
specific lymphocyte stimulation in cattle naturally infected with strains of brucella abortus and cattle vaccinated with brucella abortus strain 19.cell-mediated immune responses in cattle naturally infected with strains of brucella abortus and in cattle vaccinated with b abortus strain 19 during calfhood were studied by an in vitro lymphocyte-stimulation procedure. lymphocytes were prepared from peripheral bovine blood by the ficoll-diatrizoate technique, suspended in rpmi-1640 medium (1.5 x 10(6) lymphocytes/ml), cultured with b abortus-soluble antigen or phytohemagglutinin, and incubated for 6 days. sixteen hours prior to termination of ...1978417648
comparison of the results of some serological tests for bovine brucellosis.a total of 1887 bovine sera positive to the rose bengal plate test were subjected to other serological tests for bovine brucellosis: the complement fixation test using warm fixation (cftw),the serum agglutination test (sat) and the radioimmunoassay (ria). the sat was generally much less sensitive than the cftw. many sera, however, gave positive reactions in the sat but no reaction in the cftw or the ria. these sat reactions were attributed to igm antibody. comparison between the results of the c ...1978418114
formation of germinal centres during neonatal tolerance in the chicken.chickens were made tolerant to bsa at the time of hatching. during the tolerance, antigenic stimulation with bsa resulted in poor germinal centre formation as compared to normal immunized control birds. the tolerance persisted for at least 6 weeks. its breakdown had hardly started at the age of 12 weeks, both igm and igg antibody responses against bsa remaining negligible. stimulation with the unrelated antigens srbc and brucella abortus resulted in good antibody responses, but the number of ger ...1979495104
effect of halothane anaesthesia on secondary antibody response and mitogen-induced lymphocyte transformation in the chicken.the effect of a single halothane anaesthesia on the secondary antibody response and the lymphocyte response in vitro to phytohaemagglutinin (pha) and concanavalin a(con a) was studied. the antigens used were bovine serum albumin (bsa) and killed brucella abortus organisms (brucella). igg and igm antibodies against these antigens were quantified by solid-phase radioimmunoassay. lymphocyte transformation was studied by a whole blood micromethod. the chickens were anaesthetised for two hours with 2 ...1978716924
identification of brucella abortus antibodies in cattle serum by single radial diffusion.single radial diffusion combined with the rose bengal test permitted rapid identification of all of the brucella abortus-infected cattle in a study group of 689 animals.1976815271
the immunological properties of brucella ribosomal preparations.ribosomes were isolated from brucella abortus strains 19 and 45/20 by disruption of the cells followed by differential ultracentrifugation. the ribosome preparations contained 2-3 components reacting in immunodiffusion tests but were free of detectable lipopolysaccharide-protein agglutinogen. they crossreacted with antisera to br. abortus, br. melitensis, br. suis and br. ovis and elicited intradermal delayed hypersensitivity reactions in animals infected with br. abortus, br. melitensis or br. ...1976816681
an assessment of investigations conducted in the usa on brucella abortus strain 45/20 bacterins.the results of five investigations in cattle using 45/20 bacterins are presented and evaluated. seemingly contradictory results may be the result of one or more modifications in project design or in procedures. in these trials, there appeared to be no significant difference in the level of protection for cattle when using either intramuscular or subcutaneous routes of injection or when 10 or 12 week intervals between doses were used in cattle 6 months of age or older. also, the relative resistan ...1976816689
brucella abortus infection in the bull.observations on 2 bulls from a brucella-infected property are reported. bull 1 gave serological reactions to br. abortus in both the sat and cft from day 0 to day 141. br. abortus was not recovered from semen and the bull remained clinically normal. the serological status of bull 2 changed from negative to positive to negative over a 203 day period and remained negative for a further 74 days. semen agglutinins were only detected on one occasion (20 iu). the first clinical sign observed was epidi ...1976817703
brucellosis: the situation in western nigeria.over 55% of 7161 people examined in different parts of western nigeria have positive brucella abortus-antibodies in their sera. higher incidence of titres were found among dairy farmers and slaughtermen than in the general population. the rates of infection among the human and the cattle populations in two farms studied were very similar. there was evidence of high rate of cross-infections going on in one of these farms: more than 63% of the herd in this farm showed serological evidence of activ ...1976821186
the use of supplementary tests in the serological diagnosis of bovine brucellosis.comparative tests were carried out on serum samples using the rose bengal test (rbt), the complement fixation test (cft), the antibovine globulin test (abgt) by tube, plate and rapid variants, the mercaptoethanol test (met) and the dithiothreitol test (dtt). forty cows, from which br. abortus had been recovered, gave strong reactions in all tests except for 2 cows in the sat and 3 cows in the dtt another group of 405 cows had not yielded br. abortus on limited bacteriological examination. there ...1976823932
infection and serological responses in cattle given 45/20 vaccine and later challenged with brucella of 2 groups of 15 non-pregnant cows was vaccinated twice 6 weeks apart by the subcutaneous route with a killed adjuvant 45/20 vaccine. at the time of the first vaccination a bull was introduced for a period of 14 weeks. all animals were challenged with 1.5 x 10(7) brucella abortus organisms given into the conjunctival sac 18 weeks after the second vaccination of the vaccinated group. the largest lesions at the site of vaccination (8 cm diam.) were seen 2 weeks after inoculation. small lesion ...1976828049
evaluation of sera of leptospiral vaccinated cattle for brucella antibodies. 1976830040
vaccination against bovine brucellosis with a low dose of strain 19 administered by the conjunctival route. iii. -- serological response and immunity in the pregnant cow.seventy-four heifers, 7 to 12 months old, were randomized in four groups: group a, 8 heifers as controls; group b, 19 heifers vaccinated subcutaneously with 9 x 10(10) brucella abortus strain b 19; group c, 19 heifers vaccinated as in group b, then revaccinated by the conjunctival route 6 to 8 months later with 5 x 10(9) bacteria; group d, 28 heifers vaccinated twice by the conjunctival route with the same dose and time intervals as in group c. serological responses in agglutination, complement ...1976984715
diverse effects of bursectomy on humoral immune responses in the chicken.chickens bursectomized hormonally or surgically at various ages in embryonic to postembryonic lives were immunized with a mixture of antigens, and the antibodies produced titrated. immune responses to salmonella pullorum (sp), brucella abortus (ba). staphylococcus aureus (staph) and ovalbumin (oa) were more markedly suppressed by the bursal deprivation than those to heterogenous erythrocytes, viruses and such bacteria as pasteurella multocida (pm) and escherichia coli b. the immune response to b ...19751187514
control of brucellosis in kuwait by vaccination of cattle, sheep and goats with brucella abortus strain 19 or brucella melitensis strain rev. kuwait, approximately 12,000 dairy cows were vaccinated with a reduced dose of 3 x 10(9) brucella abortus strain 19 and approximately 350,000 sexually mature sheep and goats with a reduced dose of 10(7) b. melitensis strain rev. 1. using the criteria of prevaccinal and postvaccinal incidences of antibodies, abortions, and human cases of brucellosis, the programme was very successful. widespread vaccination of adult animals is the most effective method of controlling brucellosis among cattle, ...19921306918
antibody response to brucella outer membrane proteins in bovine brucellosis: immunoblot analysis and competitive enzyme-linked immunosorbent assay using monoclonal antibodies.sera from brucella-infected bovines were analyzed by immunoblotting by using sonicated cell extracts of b. melitensis or b. abortus and a competitive enzyme-linked immunosorbent assay (elisa) with monoclonal antibodies against outer membrane proteins (omps) with molecular masses of 10, 16.5, 19, 25 to 27, 36 to 38, and 89 kda. antibody responses against omps were compared with antibody responses against smooth lipopolysaccharide. immunoblot analysis indicated that the antibody response in infect ...19921452700
childhood brucellosis in southwestern saudi arabia: a 5-year children admitted with brucellosis at abha, saudi arabia, were studied prospectively. ninety-two per cent gave a history of animal contact, usually with sheep or goats, or ingesting raw milk, milk products, or raw liver. three-quarters of the patients had an acute or subacute presentation with diverse symptomatology: fever (100 per cent), malaise (91 per cent), anorexia (68 per cent), cough (20 per cent), abdominal symptoms (20 per cent), arthralgia (25 per cent). hep ...19921527811
antigens of brucella abortus s19 immunodominant for bovine lymphocytes as identified by one- and two-dimensional cellular immunoblotting.cellular immune responses are influential for protection against intracellular bacteria such as brucellae. therefore, identification of brucella abortus antigens that activate primed bovine lymphocytes is fundamental for discerning the breadth of cellular response in bovine brucellosis. potentially antigenic components of b. abortus s19 were isolated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by nitrocellulose blotting. specific one-dimensional blot segments induced pr ...19921587614
interaction of bovine chorioallantoic membrane explants with three strains of brucella abortus.chorioallantoic membrane (cam) explants were used to determine the in vitro growth and cytotoxic potential of 3 strains of brucella abortus. bovine cam explants were inoculated with 2 x 10(7) colony-forming units of the pathogenic strain 2308, attenuated strain 19, or the rough strain rb51 of b abortus. after inoculation, the explants were harvested and examined at 2 or 4 hours, 12 or 14 hours, and 24 or 26 hours of incubation. bacterial growth associated with each explant was determined by coun ...19921595961
effects of stage of gestation and breed on bovine responses to vaccination with brucella abortus strain 19.eighty-eight cattle were injected sc with 2.5 x 10(8) viable cells of brucella abortus strain 19. all but 1 heifer became seropositive on the basis of the results of 7 brucellosis tests, and the proportion positive decreased with time. the proportion of cattle that were seropositive during a 20- to 67-week period after vaccination was as follows, in decreasing order: hemolysis-in-gel, 59%; buffered-acid plate antigen, 39%; elisa, 16%; card, 10%; rivanol, 8%; cold complement-fixation, 7%; and aut ...19911769876
the effects of adjuvants on immune responses in cattle injected with a brucella abortus soluble antigen.five different adjuvants were examined for potentiation of humoral and cell-mediated immune (cmi) responses in cattle to a brucella abortus soluble antigen (basa). two separate experiments were performed involving a total of 64 steers, divided among six groups (experiment 1) and 9 groups (experiment 2). the adjuvants used were: muramyl dipeptide, freund's incomplete adjuvant, dimethyl-dioctadecyl ammonium bromide (dda), bordetella pertussis and propionibacterium acnes. in each experiment, three ...19911835213
differentiation by western blotting of immune responses of cattle vaccinated with brucella abortus strain 19 or infected experimentally or naturally with virulent brucella abortus.brucella abortus strain 19 salt-extractable proteins fractionated by differential ammonium sulfate precipitation were used in a western blotting method to detect bovine immunoglobulin g antibodies to b. abortus. sera from infected cattle and from cattle vaccinated with strain 19 and subsequently exposed to virulent b. abortus bound to a common group of antigens ranging in molecular weights from 31,000 to 45,000 daltons. immunoglobulin g antibodies in sera from the latter group in addition also b ...19911904667
evaluation of serologic and cellular immune responses of cattle to a nonlipopolysaccharide antigen from brucella abortus.cows naturally infected with brucella abortus developed antibody (ab) responses to a nonlipopolysaccharide antigen (nla) purified from b abortus strain 1119-3. sera from strain 19-vaccinated cows did not have detectable amounts of ab. weak lymphoproliferative responses to nla were observed in blood mononuclear cell suspensions obtained from infected cows. there was no evidence of nla-specific lymphoproliferation in cell suspensions from healthy cows. nonlipopolysaccharide antigen binding to bovi ...19902105681
brucella abortus infection in 14 farm dogs.fourteen dogs were obtained from 10 farms with brucella-infected cattle and were studied for periods ranging from 2 to 81 days. at necropsy, brucella abortus biovar 4 was isolated from all 14 dogs. mandibular, medial retropharyngeal, tracheobronchial, and mesenteric lymph nodes yielded the highest rate of recovery. urogenital infection with active shedding was seen in a single aged bitch. fecal samples (291 from 13 dogs) were b abortus culture negative. ten dogs monitored serologically over time ...19902107157
bovine t-lymphocyte lines reactive with brucella abortus.bovine t-cell lines reactive with brucella abortus were established by repeated stimulation with b abortus and mitomycin c-treated autologous antigen-presenting cells. representative results were obtained, using 33 cell lines from 14 cows. cultures responded to the virulent laboratory strain 2308, the vaccine strain 19, and the rough mutant strain rb51 in thymidine-incorporation assays. the cells in these cultures required antigen-presenting cells for their response to b abortus. autologous anti ...19902109554
immunopathology of experimental brucella abortus strain 19 infection of the genitalia of bulls.antibody responses in serum and semen, and immunoglobulin containing cell (icc) populations in the genitalia of bulls were compared after inoculating brucella abortus strain 19 into the seminal vesicles of two bulls (isv route) and into testes in two other bulls (it route). bulls seroconverted as early as 1 week post-infection (pi). peak serum titres as determined by the serum agglutination test (sat), complement fixation test (cft) and elisa occurred at pi weeks 3, 4 and 5 respectively. highest ...19902111057
enzyme immunoassay using mouse monoclonal anti-bovine antibodies for the detection of brucella abortus antibodies in cow milk.individual milk samples and artificially constructed tank milk samples from cows with naturally occurring brucellosis were examined by the enzyme-linked immunosorbent assay (elisa) using sonicated b. abortus s-99 antigen, and mouse monoclonal anti-bovine igm, iga, and igg1 conjugates. elisa results were compared with the results of the milk ring test using either 1 ml milk (mrt-1) or 8 ml milk (mrt-8). the elisa using mouse monoclonal anti-bovine igg1 conjugate was sensitive and specific. in tes ...19902127977
comparison of brucella abortus and b melitensis antigens for the rose bengal plate test on sera from cattle infected with b abortus biovar-5. 19852414899
serological cross-reactions between brucella abortus and yersinia enterocolitica 0:9.yersinia enterocolitica (ye) 0:9 is an organism of great significance in veterinary medicine largely as a result of its cross-reaction with brucella abortus (ba). boty ye 0:9 and ba possess somatic antigens in common; as a result of which animals exposed to ye 0:9 have an immune response which is distinguishable only with difficulty from that induced by ba. cattle were exposed to ye 0:9 by the oral or intramammary routes. oral exposure failed to generate significant serologic response. in contra ...19852422134
localization of antigen-specific lymphocytes following lymph node challenge.the effect of subcutaneous injections of brucella abortus strain 19 antigen on the specific localization of autologous lymphocytes in the regional nodes of calves was analysed by fluorescent labelling and flow cytometry. both in vitro and in vivo fitc labelling of lymphocytes indicated the preferential migration of lymphocytes from a previously challenged lymph node to a recently challenged lymph node. however, lymphocytes from a lymph node challenged with b. abortus failed to localize preferent ...19862426183
brucella abortus regulates bovine macrophage-t-cell interaction by major histocompatibility complex class ii and interleukin-1 expression.t-cell activation is dependent on nominal antigen associated with major histocompatibility complex (mhc) class ii molecules and interleukin-1 (il-1), both provided by antigen-presenting cells. we have studied the effects of brucella abortus and recombinant bovine gamma interferon (ifn-gamma) on bovine macrophage expression of mhc class ii and il-1 molecules and subsequent t-cell proliferation in response to b. abortus. when peripheral blood mononuclear cells were cocultured with b. abortus and i ...19892494112
dot-enzyme linked immunosorbent assay for the detection of antibodies in bovine brucellosis.a dot-enzyme linked immunosorbent assay (dot-elisa) for the detection of antibodies in bovine brucellosis using soluble antigens extracted from brucella abortus s-99 is described in which antigen was deposited on a nitrocellulose sheet (0.5 x 0.5 cm) bound to a plastic strip and the unsaturated sites blocked by a solution of spray-dried milk powder. sera were tested at dilutions of 1:800 and 1:1600, using rabbit anti-bovine-immunoglobulin or protein-a coupled to peroxidase as conjugates and diam ...19892495563
macrophage function in mammary glands of brucella abortus-infected cows and cows that resisted infection after inoculation of brucella abortus.nonvaccinated pregnant cows were segregated retrospectively into 2 groups following inoculation with brucella abortus strain 2308. one group resisted infection (resistant cows) and the other group developed active infections (susceptible cows) and subsequently aborted. mammary gland macrophages collected from the 2 groups of cows were compared, using in vitro functional assays. in a chemiluminescence assay, mammary gland macrophages from resistant cows produced significantly (p = 0.014) higher o ...19892496628
uptake and excretion of brucella abortus in tissues of the face fly (musca autumnalis).to determine their capacity to host brucella abortus, face flies were examined 1 to 120 hours after feeding on broth containing bacteria and bovine erythrocytes. brucella abortus was cultured in large numbers from whole flies for 12 hours after feeding, but not after 72 hours. histologic analysis showed that brucellae were rapidly taken into the midgut, sequestered from erythrocytes, transiently stored, and shed in the feces; there was no evidence of bacterial replication within epithelial cells ...19892506781
bovine monoclonal antibody specific for brucella abortus lipopolysaccharide.the development of a bovine monoclonal antibody against brucella abortus smooth lipopolysaccharide (bm-8) by interspecies fusion of bovine peripheral lymphocytes from an immunized cow and a murine plasmacytoma cell line is described. the twice cloned cell line secreted bovine igg1 subclass antibody. ascites fluid was prepared in pristane treated nu/nu mice by intraperitoneal injection. the pooled ascites fluid was purified by affinity chromatography and the functions of the antibody assessed in ...19892508298
effects of in vitro and in vivo administration of recombinant bovine interferon-gamma on bovine neutrophil responses to brucella abortus.the effects of in vitro and in vivo treatment of bovine polymorphonuclear leukocytes with recombinant bovine interferon-gamma on in vitro bovine polymorphonuclear leukocyte functions and the survival of brucella abortus were determined. activation of neutrophils in vitro with interferon-gamma resulted in enhanced production of o2- and myelopeoroxidase-h2o2-halide activity by neutrophils in the presence of b. abortus. the improved iodination responses were correlated with an enhanced ability to p ...19892539694
sepracell-mn for mononuclear cell separation from cattle: effect on mitogen-and antigen-induced lymphocyte blastogenesis.mononuclear leukocytes (mnc) were separated from heparinized and edta-treated whole bovine blood by centrifugation after mixing with a commercial colloidal silica preparation (sepracell-mn (s-mn]. cell yields and lymphocyte blast transformation (lbt) to pokeweed mitogen (pwm), phytohaemagglutinin (pha), concanavalin a (con a), and brucella abortus antigens were tested against mnc obtained from heparinized whole blood using ficoll-hypaque (fh). separation with s-mn was more rapid and less labor i ...19892557707
inflammatory cell and immune function in merino sheep with chronic dermatophilosis.components of inflammatory and immunological responses were compared in 17 merino sheep with chronic dermatophilosis (group 1) and 15 merino sheep that had recovered from the disease (group 2). the functions studied included: (i) total and differential white cell counts; (ii) phagocytic function and intracellular killing by neutrophils; (iii) humoral immune response to t-dependent and t-independent antigens and to dermatophilus congolensis. (iv) lymphocyte blastogenic responses to phytohaemagglu ...19892623798
opsonin-dependent stimulation of bovine neutrophil oxidative metabolism by brucella abortus.nonopsonized brucella abortus and bacteria treated with fresh antiserum, heat-inactivated antiserum, or normal bovine serum were evaluated for their ability to stimulate production of superoxide anion and myeloperoxidase-mediated iodination by neutrophils from cattle. brucella abortus opsonized with fresh antiserum or heat-inactivated antiserum stimulated production of approximately 3 nmol of o2-/10(6) neutrophils/30 min. similarly treated bacteria also stimulated the binding of approximately 4. ...19882831760
isolation of components of brucella abortus responsible for inhibition of function in bovine neutrophils.the effects of fractions of brucella abortus strain 2308 on functions of bovine polymorphonuclear neutrophils (pmns) were examined in vitro. ingestion of staphylococcus aureus and reduction of nitroblue tetrazolium dye by bovine pmns were not inhibited by heat-killed b. abortus. the ability of pmns to iodinate proteins was significantly inhibited by live or heat-killed b. abortus and supernatant from heat-killed cells but not by washed heat-killed cells. two inhibitory components isolated from t ...19852995513
pathogenesis of placentitis in the goat inoculated with brucella abortus. i. gross and histologic lesions.pregnant goats were given brucella abortus intravenously or in uterine arteries, and tissues from the uterus and placentae were examined at various post-inoculation intervals to study mechanisms of placental infection. placentitis was present by 5 days post-inoculation and abortions occurred within 11 days. b. abortus was identified in placentae by light microscopy and immunoperoxidase techniques. b. abortus was first seen in erythrophagocytic trophoblasts of the placentome. subsequently, high n ...19863088809
comparison of an enzyme-linked immunosorbent assay using monoclonal antibodies and a complement fixation test for cattle vaccinated and infected with brucella abortus.a competitive enzyme-linked immunosorbent assay (elisa) using a monoclonal antibody conjugated to horseradish peroxidase ma(a) and a complement fixation test (cft) were applied to sera collected over a two-year period from 60 cattle challenged with brucella abortus strain 544. forty-eight of the cattle were previously vaccinated with b. abortus strain 19 (s19) or b. abortus strain 45/20 (45/20). after challenge 33 of the cattle remained uninfected and nine of the 27 infected cattle showed aberra ...19863088822
preliminary evidence for a diagnostic immunoglobulin g1 antibody response among culture-positive cows vaccinated with brucella abortus strain 19 and challenge exposed with strain 2308.the sera of cows inoculated with brucella abortus have a characteristically high titer of immunoglobulin (ig) g1 antibodies to a soluble brucella antigen compared with sera of noninoculated vaccinated cattle. concentrations of antigen-specific igg1 were greater than 10-fold higher than those for igg2, even though total igg2 concentrations were higher than total igg1 concentrations. increases in igg1 antibodies to brucella abortus soluble antigen were detected shortly after vaccination in those c ...19863089082
ultrastructural morphometric analysis of brucella abortus-infected trophoblasts in experimental placentitis. bacterial replication occurs in rough endoplasmic reticulum.trophoblasts in normal and brucella abortus-infected caprine placentas were examined by ultrastructural morphometric analysis to establish structural relationships of b abortus with cytoplasmic organelles; brucellae were identified with colloidal gold-labeled anti-b abortus bovine igg. cytotrophoblasts had large numbers of b abortus in cisternae of rough endoplasmic reticulum; binucleate trophoblasts did not contain bacteria. in infected trophoblasts there was a significant hypertrophy of b abor ...19863090887
comparison of the results of card, rivanol, complement-fixation, and milk ring tests with the isolation rate of brucella abortus from cattle.specimens from 4,553 cows were examined by card, rivanol, and complement-fixation (cf) tests and bacteriologic culture. a ring test was performed on milk from 1,003 of these cows. the isolation rate of brucella abortus correlated directly with antibody titers, and the field strain predominated in adult-vaccinated cows when the rivanol test titer was greater than + 100 and the cf test titer was greater than 4 + 40. the cf test had the best balance of sensitivity and specificity in adult-vaccinate ...19863090911
production of auto-anti-idiotypic antibody during the normal immune response. xii. enhanced auto-anti-idiotypic antibody production as a mechanism for apparent b-cell tolerance in rabbits after feeding antigen.rabbits fed trinitrophenylated bovine serum albumin (tnp-bsa) generated fewer anti-tnp plaque-forming cells but greater numbers of hapten (tnp)-augmentable igm and igg pfc following immunization with tnp-ficoll or tnp-brucella abortus than did animals not previously fed antigen. spleen and mesenteric and bronchial lymph nodes were similarly affected. in addition more auto-anti-idiotype (id) antibody (anti-anti-tnp) was eluted by hapten from spleen cells of antigen-fed rabbits than from spleen ce ...19863091266
the relationship between the isolation of brucella abortus and serological status of infected, non-vaccinated cattle.seventy two non-vaccinated cattle with various complement fixation (cf), rose bengal (rb) and enzyme-linked immunosorbent assay (elisa) results at slaughter were examined bacteriologically and serologically. brucella abortus was recovered from 49 (68.1%) of the cattle and the use of a biphasic culture medium was entirely responsible for the detection of 6 (12.2%) of the culture positive cattle. the supramammary and retropharyngeal lymph nodes were the most rewarding tissues to culture. a compari ...19863094489
identification of brucella abortus in formalin-fixed, paraffin-embedded tissues of cows, goats, and mice with an avidin-biotin-peroxidase complex immunoenzymatic staining avidin-biotin-peroxidase complex immunoenzymatic staining technique was evaluated for light microscopic detection of brucella organisms in formalin-fixed, paraffin-embedded tissues. tissues from cows, goats, and mice inoculated with b abortus strain 2308 were examined, using rabbit antiserum to brucella cell surface protein as primary antibody. stained organisms were identified histologically in tissue sections containing b abortus, as detected by bacteriologic examination of duplicate nonpro ...19863096172
detection of antigenic fractions from brucella abortus s45/20 which bind to non-agglutinating antibodies using electroblotting and enzyme-linked antibody probes.outer membrane antigens which bind to non-agglutinating antibodies (naab) elicited by smooth (s19) and rough (s45/20) brucella abortus strains, were extracted from s45/20 by stirring in cold 2.5% nacl and then analyzed by sds-page, electroblotting and enzyme-linked antibody test. eight bands were observed in the gel stained with coomassie blue. seven antigenic fractions were transferred to nitrocellulose by blotting. a 27-kd band was recognized by bovine anti-s45/20 non-agglutinating serum and n ...19863097916
comparison of the susceptibility of brucella abortus isolates obtained before and after cows were treated with oxytetracycline and streptomycin.eight isolates of brucella abortus were obtained from cows before and after they were treated with oxytetracycline and streptomycin. the susceptibility to these antibiotics was determined by broth-dilution minimal inhibitory and minimal lethal concentrations. differences were not found in the minimal lethal concentrations of oxytetracycline or streptomycin in isolates obtained from cows before and after they were treated. this indicates that treatment failures in the cows were not the result of ...19863099613
distinct fixation of defined amounts of complement by the brucella abortus antigen and bovine antibodies under different incubation conditions in the cft.different times and temperatures of the 1st phase incubation of the complement fixation test (cft) were used. it was found that a similar decrease in complement (c') activity occurred after 2 h at 37 degrees c, after 8 h at 20 degrees c and after 18 h at 4 degrees c. simultaneously, in the same periods a double increase in standard serum titre at 4 and 20 degrees c was noted in comparison with titre at 37 degrees c. this increase of sensitivity of the cft at 4 and 20 degrees c appeared to be a s ...19863100131
[standardization of the complement fixation test (cft) in brucellosis. i. the polish standard of anti-brucella abortus serum].the purpose of this paper was to prepare an indigenous standard of anti-brucella abortus serum for the complement fixation test (cft) as a homologue of the secon international standard of anti-brucella abortus serum (isabs-ii), which contains 1000 international units of complement-fixing antibodies in 1 cm3. the indigenous standard of anti-brucella abortus serum (isabas) was prepared in 1975. the material used was the serum of a cow infected with br.abortus, biotype 1, under natural conditions. ...19863103110
antibodies in calves on feed supplemented with chlortetracycline after vaccination with brucella abortus strain 19.twenty dairy heifers each consumed 350 mg of chlortetracycline/day in their feed. four tests were performed on serum specimens from these and 20 control calves after vaccination with brucella abortus strain 19. the numbers of positive test results on the card test and mean titers on the tube and rivanol agglutination and complement-fixation tests were compared in the 2 groups. using the rivanol and complement-fixation tests, there were differences in the mean titers at weeks 5 and 6 after vaccin ...19873106273
examination of lochia as an aid to the early diagnosis of bovine brucellosis.the standard technique for diagnosing bovine brucellosis is the serological examination of blood samples. as affected females may excrete large numbers of the brucella organism in the lochia, the bacteriological and smear examination of such material appeared to be a suitable alternative for early diagnosis. of the lochia samples collected from 210 cows and heifers within 12-24 h after parturition or abortion, 10.9% were bacteriologically positive. only 70% of these could be diagnosed correctly ...19863106635
bovine igm: does it fix guinea pig complement in the absence of bovine complement components?purified bovine isotypes igm, igg1, igg2, and iga (secretory), affinity purified with brucella abortus, were tested in a complement fixation test (cft) for their ability to activate guinea pig complement directly or in the presence of 'normal' bovine serum. only igg1 fixed guinea pig complement in the direct test and approximately 250 ng of antibody was required to activate 50% of 3 ch50 units with a standard amount of antigen. addition of 'normal' bovine serum as an additional source of complem ...19873111076
the identity, distribution and epizootiological significance of brucella isolates in australia, 1981 to 1985.results listing the identification of brucella isolates received by the national brucellosis reference centre, national biological standards laboratory, canberra from 1981 to 1985 are presented. the distribution of brucella species and biotypes is shown on a host and state basis. cultures isolated in australia were identified as brucella abortus biotypes 1, 2 and 4, and strain 19; b. suis biotype 1, and b. ovis. b. melitensis biotype 3 was recovered from man infected in the mediterranean area. b ...19873111457
immunochemical and partial chemical characterization of fractions of membrane-bound smooth lipopolysaccharide-protein complex from brucella abortus.smooth lipopolysaccharide (slps) of brucella abortus was prepared and fractionated by a modification of the procedures of moreno et al. (j. bac. 138:361-369, 1979). washed b. abortus cells were disrupted by 21 freeze-quick thaw cycles with ultrasonication to separate the non-membrane-bound material. ultrasonicated bacteria were used for preparation of membrane-bound slps (approximately f5, the main crude slps fraction described by moreno et al.). phenol extraction was repeated 3 times and then w ...19873114618
preparation by ultrafiltration and control by high-performance liquid chromatography of the native hapten of brucella abortus for use in radial immunodiffusion diagnostic effective method was developed for the preparation of brucella abortus native hapten by use of an ultrafiltration system. the membranes pm30 and ym5 were used to separate the lipopolysaccharide and the native hapten. the yield of the native hapten was higher than that obtained by a more complex procedure reported previously. this method is economical for the large-scale preparation of b. abortus native hapten. the effects of ultrafiltration were evaluated by a quick and sensitive high-perform ...19873117841
bovine ileal dome lymphoepithelial cells: endocytosis and transport of brucella abortus strain 19.ligated ileal loops of calves were inoculated with brucella abortus and examined at 2, 4, 6, 10, and 24 hours post-inoculation. b. abortus was identified by light and electron microscopy using immunoperoxidase and antibody-coated colloidal gold techniques. b. abortus was detected in vesicles, phagolysosomes, and large vacuoles of lymphoepithelial cells. numbers of intracellular bacteria decreased with time after inoculation. b. abortus was also seen between and below lymphoepithelial cells and f ...19883125659
effect of bovine non-agglutinating antibodies on the blood clearance of 131i-labelled brucella abortus strain 45/20.non-agglutinating anti-brucella abortus s45/20 antibodies were isolated and purified from sera of immunized cattle by means of immunoadsorption and ion-exchange chromatography (deae-sephadex a-50). they corresponded to the igg1 isotype as shown by immunoelectrophoresis using monospecific anti-igg1 and anti-bovine gamma globulin sera. these antibodies failed to agglutinate the antigen. they were detected by the anti-bovine gamma globulin test, showing higher titres than those of agglutinating ant ...19873125666
histopathologic findings in brucella abortus-infected, pregnant goats.twenty-eight pregnant goats in midgestation were exposed to a bovine pathogenic strain of brucella abortus to determine the histologic changes associated with infection. does were necropsied 0 to 7 days or 4 to 6 weeks after delivery of aborted, stillborn, or live, full-term fetuses. aborted and stillborn fetuses were necropsied within 16 hours of delivery. selected, paired tissue specimens were collected for histologic and bacteriologic examination. an avidin-biotin-peroxidase complex immunosta ...19883126686
an elisa using an sds extract of brucella abortus strain 99 as antigen to detect b. abortus antibodies in cattle elisa was developed using an sds extract of brucella abortus as antigen to detect antibodies in cattle sera. the antigen was stable at 4 degrees c for at least 4 years and although it gave optimal results at a 1/4,000 dilution it could detect reactors at a 1/32,000 dilution. based on comparative cf tests on 430 sera from negative herds and 187 sera from positive herds a reading of 0,07 or less using a 492 nm filter could be considered a negative reaction. the elisa could be a useful test to s ...19883127768
[standardization of the complement fixation test (cft) in brucellosis. ii. the antigen].the activity of cellular antigens and those as aqueous extracts prepared from 4 laboratory strains of brucella abortus: 99, s-19, 119-3 and "krotz" has been compared in this paper. the purpose of the studies was to select an antigen of the highest activity and to test it by the polish standard of anti-brucella abortus serum. it was shown that cellular antigens are more active in cft than aqueous extract antigens of the same brucella strain. cellular suspension of br. abortus strain s-19 was chos ...19863129702
[standardization of the complement fixation test (cft) in brucellosis. iv. incubation conditions].a differentiated time and temperature of incubation were used in the first cft phase. it was found that the activity of complement fixation (c') decreased in the reaction medium. this was observed in the control system in which at 1 c'h50 hemolysis inhibition increase from 50 to 90% was found after 2 hr at 37 degrees c, after 8 hr at 20 degrees c and after 18 hr at 4 degrees c. simultaneously, a double increase of the standard serum titre was obtained at 4 and 20 degrees c as compared with that ...19863129703
some aspects of experimental bovine the course of eight successive brucella abortus experiments, 394 cows were followed by clinical, serological and bacteriological examinations. cultures were made from vaginal swabs and colostrum at delivery and from 10 pools of lymph nodes or organs sampled at slaughter, about 6 weeks after calving. from these cows, 346 had been experimentally challenged with 1.5 x 10(7) b abortus strain 544 via the conjunctiva, 3 congenitally infected and 45 bought from known naturally infected herds. males ...19873132076
brucella abortus 1119-3 o-chain polysaccharide to differentiate sera from b. abortus s-19-vaccinated and field-strain-infected cattle by agar gel immunodiffusion.purified brucella abortus 1119-3 and brucella melitensis 16m lipopolysaccharide o-chain polysaccharides were not precipitated in agar gel immunodiffusion by any of 24 sera from vaccinated cattle but were precipitated by 18 of 24 sera from infected cattle. this difference can be used to differentiate sera of cattle vaccinated with b. abortus s-19 from sera of some field-strain-infected cattle.19883133389
[100 years of bacteriology: the history of the discovery of brucellosis. 2: discovery of the etiology of infectious abortion in cattle by the danish veterinary pathologist bernhard bang and proof of the relation of "micrococcus melitensis" and and "bacillus abortus" by the american microbiologist alice evans]. 19883136596
a review of enzyme immunoassay for detection of antibody to brucella abortus in cattle.enzyme immunoassay has gained wide acceptance for serological diagnosis of bovine brucellosis because of its ability to detect antibody of all isotypes unlike the conventional tests. the indirect enzyme immunoassay, however, presents several parameters that require careful analysis. these parameters include the choice of antigen and antiglobulin-enzyme conjugate reagents for use in the assay, dealing with the large amount of data the semi-automatic or automatic assay can generate and the inter- ...19883137720
characterization of an atypical biotype of brucella abortus.brucella abortus strains were isolated from bovine tissue and milk samples from seven ontario herds. the isolates were characterized by colonial morphology, requirement of co2 for growth, lysis by tbilisi phage, biochemical tests and agglutination in monospecific sera. they resembled b. abortus biotype 2 (on the basis of sensitivity to thionin and basic fuchsin) and biotype 4 (on the basis of agglutination with anti-brucella "m" but not anti-brucella "a" absorbed sera). sodium dodecyl sulphate-p ...19883139274
structural and immunochemical aspects of brucella abortus endotoxins.smooth lipopolysaccharide (slps) of brucella abortus, which is the most immunodominant component among the antigens of b. abortus isolated, has been used for diagnosis for decades. high yields of slps can be prepared by a modification of the procedures of moreno et al. (j. bacteriol. 138:361-369, 1979). washed b. abortus cells can be disrupted by 21 freeze-quick thaw cycles and ultrasonication to separate non-membrane-bound material; then phenol extraction is performed 3 times and the phenol fra ...19883140612
distribution of brucella abortus organisms in calves after conjunctival exposure.thirty calves (3 to 4 months old) were exposed conjunctivally to a pathogenic strain of brucella abortus. calves were euthanatized and necropsied at postexposure hours 2 and 4, and at postexposure days (ped) 1, 4, 7, 14, 21, 42, and 49. selected ocular, pharyngeal, and lymphoid tissues were cultured bacteriologically for brucellae to determine organism distribution. brucella abortus organisms initially localized in the third eyelids, bulbar conjunctivae, and parotid lymph nodes and were detected ...19883149162
further evidence that bovine igm does not fix guinea pig a study of sera from cattle vaccinated with 3 x 10(10) cfu of brucella abortus strain 19, it was found that igg1 antibody measured by an indirect elisa was the only isotype to correlate with standard complement fixing antibody titers using heated serum samples and guinea pig serum as a source of complement. a supplement of normal unheated bovine serum resulted in igm fixing guinea pig complement, giving data similar to those obtained with unheated serum in the complement fixation test.19883150884
antibody isotype response in adult cattle vaccinated with brucella abortus a chronological study of sera collected from eight adult cattle vaccinated with 3 x 10(-10) cfu of brucella abortus s19, antibody of each of the four major isotypes was measured by indirect enzyme immunoassay (elisa) and by direct and modified complement fixation tests (cft). six of the cattle gave antibody responses to the vaccine strain that commenced between days 5 and 8 for all the isotypes in the elisa, peaked by 1 to 4 months and then declined to low levels by 10 months. direct cft and ...19883150885
contact dermatitis caused by brucella.we report a case of a distinctive dermatitis in a dairy worker exposed to brucella abortus while manually delivering an infected calf. the rapid onset of pruritus, the strict limitation of lesions to the upper extremities, and the negative results on growth of culture for microorganisms make direct bacterial infection an untenable cause in this case. allergic hypersensitivity is the probable mechanism, manifesting itself initially as contact urticaria. coincidentally our patient also had systemi ...19853158485
resistance of preimplantation bovine embryos to infection with brucella abortus.preimplantation bovine embryos were exposed in vitro to brucella abortus to determine if the bacteria would adhere to zona pellucida (zp)-intact embryos or adhere to or infect zp-free embryos. brucella abortus was not isolated from zp-intact or zp-free groups of embryos after 10 sequential antibiotic-free washings. brucella abortus was isolated from all groups containing zp-defective embryos after the exposure period and washing. detrimental effects on healthy in vitro development of embryos wer ...19863767099
assessment of bovine mammary gland macrophage oxidative burst activity in a chemiluminescence assay.a major bactericidal mechanism of neutrophils and macrophages is the generation of toxic oxygen-free radicals upon phagocytosis of microbes. studies were conducted to assess the oxidative metabolism of bovine mammary gland macrophages. bovine mammary gland macrophages were challenge exposed with a variety of phagocytic stimuli in an in vitro, luminol-assisted chemiluminescence assay. a measurable oxidative burst was observed when macrophages were challenge exposed with heat-aggregated bovine imm ...19873826830
a competitive enzyme immunoassay for the detection of bovine antibodies to brucella abortus using monoclonal antibodies.a competitive enzyme immunoassay (eia) for the detection of circulating bovine antibodies to brucella abortus has been developed using horseradish peroxidase conjugated monoclonal antibodies (mab) raised against b. abortus cell surface antigens. antibodies present in the serum of either vaccinated or infected cattle can apparently displace the conjugated mab from the lipopolysaccharide antigen (lps) in a quantitatively different manner allowing an assessment of immune status of the animal. the r ...19853922105
delayed-type hypersensitivity responses induced by bovine colostral components.transfer factor-type substances obtained from leukocytic cells and fluid portions of bovine colostrum caused effective passive transfer of delayed-type hypersensitivity responses across species barriers. passive transfer of brucella abortus sensitivity was obtained with equal regularity when using components derived from peripheral blood and colostrum of dams sensitized at 3 and 9 months of age. colostral feedings to calves caused the passive transfer of delayed-type hypersensitivity as early as ...19853925823
profiles of serological reactions following adult cow inoculation with standard dose brucella abortus strain 19 vaccine.experimental use of the standard dose (4-12 x 10(10) viable organisms per dose) brucella abortus strain 19 vaccine (s19) in adult cattle led to a serological response in the complement fixation test (cft) within 2 weeks. the antibody titres recorded could not be distinguished from those arising from infection for a period of 6-11 months. this was in the absence of the booster effect of brucella antigen from either field or vaccine strains. the illegal or unintentional use of s19 in adult cattle ...19853927001
a "dipstick" enzyme immunoassay for detection of antibody to brucella abortus in cattle enzyme immunoassay that utilizes antigen bound to a matrix which can be removed from the substrate to stop development is described. the assay which is performed in glass or plastic disposable tubes uses gel-bond film strips for attachment of antigen. the only equipment requirements are a rotary shaker and a spectrophotometer (optional). the antigen coated strips are passed through a series of tubes containing test serum, wash solution, antibody-enzyme conjugate, wash solution and substrate-c ...19853930057
application of a timing protocol to the reduction of inter-plate variability in the indirect enzyme immunoassay for detection of anti-brucella antibody.a simple timing protocol was developed to monitor chromogen conversion in an enzyme immunoassay, performed in microtiter plates, for the detection of antibody to brucella abortus in bovine serum. application of this protocol decreased the inter-plate coefficient of variation from 28.6% to 6.8% when optical density (od) values, subsequent to the reaction of a standard antibody reagent, were compared to a static development time. substantial reductions in variation were also observed for low titer ...19853930575
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