| resistance to marek's disease. effect of corynebacterium parvum and marek's tumor cell vaccines on tumorigenesis in chickens. | a study of nonspecific stimulation of the avian immune system with corynebacterium parvum and specific stimulation with marek's tumor cell vaccines revealed that nonspecifically stimulated outbred white leghorn-type cockerels had higher incidences of tumors than did controls. a study of tumor cell cytotoxicity of sera from marek's disease virus exposed birds indicated that humoral factors may play some role in tumor resistance. | 1978 | 24754 |
| marke's disease herpesviruses. iii. purification and characterization of marek's disease herpesvirus b antigen. | sera from chickens naturally infected with marek's disease herpesvirus (mdhv) form preciptin lines with at least two immunologically distinct soluble antigens designated mdhv-a and mdhv-b. partial purification and characterization of the glycoprotein mdhv-a antigen was previously reported. mdhv-b was found predominantly in the sonically treated extracts of infected cells, in contrast to the predominantly extracellular mdhv-a. analysis of these extracts from 14cglucosamine-labeled cells by immuno ... | 1978 | 29134 |
| [comparative antigenic characteristics of 2 marek's disease virus variants and of herpesvirus of turkeys isolated in the ussr]. | the antigens induced by pathogenic (55) and nonpathogenic (83) variants of marek's disease virus, the kekava strain (mdv-kekava) and herpesvirus of turkeys, the m-24-72 strain (hvt-m24-72) were tested in the agar gel precipitation test. the antigens were prepared from feather follicles (ff) of the infected chickens, from the infected cultures of chick embryo fibroblasts (cef) and from the culture fluid (cf) of these culttures. in the ff and cef cultures infected with mdv-kekava-83, the synthesis ... | 1976 | 64031 |
| characterization of a new serotype of marek's disease herpesvirus. | the hprs-24 strain of marek's disease herpesvirus was selected for closer study from a group of virus isolates that appeared apathogenic under standard test conditons. protection studies revealed an immunological relationship between this virus strain and acute marek's disease herpesvirus. in chicken kidney cell cultures, the hprs-24 strain caused small and slowly developing plaques, and the proportion of infected cells was less than with other strains. in chicken embryo fibroblast cultures, thi ... | 1975 | 66180 |
| cell-mediated cytotoxic response to cells bearing marek's disease tumor-associated surface antigen in chickens infected with marek's disease virus. | in a microcytotoxicity test in which 51cr-labeled cells of a marek's disease (md) lymphoblastoid line (msb-1 line) were used, cell-mediated cytotoxicity of spleen cell suspensions prepared from chickens inoculated with md virus was demonstrated. this cytotoxic response, presumably directed against md tumor-associated surface antigen, was detectable briefly after virus infection and paralleled the appearance of early lymphoproliferative lesions characteristic of md. | 1977 | 68120 |
| [structure and function of virus-induced antigens in cultured cells infected with marek's disease and turkey herpes viruses. i. alteration of the immunological specificity of plasma membranes in infected cells (author's transl)]. | virus-induced proteins were detected in the plasma membranes of cells infected with marek's disease (mdv) and turkey herpes (hvt) viruses and analyzed by biochemical and serological methods. the virus-induced membrane proteins were shown to induce virus-neutralizing antibodies and to protect inoculated chickens against the challenge infection with oncogenic mdv. two virus-induced proteins at least were also demonstrated by the sds polyacrylamide gel electrophoresis in the purified plasma membran ... | 1977 | 72346 |
| characterization of an apparently nononcogenic marek's disease virus. | a new isolate of marek's disease virus (mdv) was described. this virus, sb, and a clone, sb-1, differed from pathogenic isolates in in vitro growth characteristics as described for other apathogenic isolates. serologically, as with other apathogenic isolates, sb could be distinguished from pathogenic mdv and the avirulent turkey herpesvirus. sb failed to induce lesions characteristic of marek's disease (md) during a 6- to 11-week experimental period. also, sb was nononcogenic in immunosuppressed ... | 1978 | 76680 |
| a phosphonoacetate-resistant mutant of herpesvirus of turkeys. | a phosphonoacetate (pa)-resistant mutant of the herpesvirus of turkeys (hvt) was isolated and characterized. the mutant of hvt resistant to pa (hvtpa) replicated in duck embryo fibroblast (def) culture in media containing 300 microgram pa/ml, whereas the replication of the wild type of hvt (hvtwt) was completely inhibited in def culture in media containing 100 microgram pa/ml. the hvtpa was distinct from the hvtwt in plaque morphology, but was indistinguishable antigenically and showed in vitro ... | 1978 | 76681 |
| demonstration of chicken fetal antigen (cfa) on normal splenic lymphocytes, marek's disease lymphoblastoid cell lines and other neoplasms. | chicken fetal antigen (cfa) was detected on normal splenic lymphocytes and a direct relationship was observed between the percentage of cfa-positive cells and the age of the donor. the fetal antigen was also detected on lymphoblastoid tumor cells and cell lines induced by known avian oncogenic viruses (marek's disease virus and avian leukosis virus), and on spontaneously occurring adenocarcinoma cells. the fetal antigen appears to be distinct from marek's disease tumor-associated surface antigen ... | 1979 | 90665 |
| studies on the mechanism of vaccinal immunity to marek's disease. | | 1978 | 93038 |
| [immunological aspects of marek's disease in chickens with maternal antibodies]. | the dynamics of the production of immunoprecipitation antibodies to marek's disease virus was studied in the serum of chickens with maternal antibodies in relation to the occurrence of the immunoprecipitation antigens of marek's disease virus in feather follicles. one-day-old chickens were infected by the contact method with marek's disease virus. the first occurrence of immunoprecipitation antigen was detected on the 14th day after infection and this occurrence persisted throughout the experime ... | 1978 | 99864 |
| properties of a chicken lymphoblastoid cell line from marek's disease tumor. | properties of a chicken lymphoblastoid cell line (msb-1) from a marek's disease tumor were studied. the cell line grew well at 41 degrees c in medium rpmi-1640 supplemented with 10% bovine fetal serum and had a doubling time of 8-12 hours. cells grown in stationary suspension culture did not attach to the vessel and had the morphology of typical lymphoblasts. at 37 degrees c, the cell line grew initially but ceased to divide after several subcultures. in the subcultures maintained for 48-72 hour ... | 1975 | 163334 |
| natural pox and herpes as a dual virus infection in chickens. | a natural dual viral infection was confirmed in chickens of university of illinois poultry farm by histopathologic, immunologic, and electron-microscopic examination of formalin-fixed tracheal tissue. histopathologic examination of the tracheal mucosa revealed eosinophilic cytoplasmic inclusions characteristic of fowlpox and intranuclear inclusions suggestive of marek's disease. treatment of the formalin-fixed tracheal tissue with peroxidase and fluorescent-labeled antibody against marek's disea ... | 1975 | 164178 |
| in ovo assay for marek's disease virus and turkey herpesvirus. | marek's disease virus (mdv) and the turkey herpesvirus (hvt) may be assayed on the chorioallantoic membrane (cam) of the chicken embryo after intravenous inoculation of chicken embryo fibroblasts (cef) or chicken blood leukocytes infected with these viruses. free hvt, mdv associated with marek's tumor cells, and lymphoblastoid cell lines derived from marek's tumors, may be assayed in the same way. the intravenous assay is quicker than the yolk sac assay and somewhat more sensitive than in vitro ... | 1975 | 164413 |
| pathogenic and serologic studies of japanese quail infected with jm strain of marek's disease herpesvirus. | japanese quail were inoculated with marek's disease herpesvirus at 1 day of age, and a second group of the same age was infected by contact with inoculated quail. a third group raised in our laboratory as a source of hatching eggs was accidentally infected with marek's disease (md). all quail were observed and examined for periods up to 360 days; the usual clinical signs of md were not observed. however, the birds were susceptible to md infection because of the evidence that: 1) the md-specific ... | 1975 | 164560 |
| newer knowledge in comparative virology--its contribution to human health research. | like other comparative sciences, and despite its recent beginning comparative virology has already contributed useful applications and observations to human health research. teachings derived from the study of marek's disease found application in that of burkitt's lymphoma, and may lead to a possible vaccine against the human disease. equally useful information came from the study of canine distemper in the development of a chorio-allantoic membrane attenuated measles vaccine, and in our knowled ... | 1975 | 167504 |
| studies of marek's disease herpesvirus and turkey herpesvirus specific common antigen which stimulates the production of neutralizing antibodies. | an agar-gel precipitation antigen prepared from the skin (feather-ag) of chicken infected with jm strain of marek's disease herpesvirus (mdhv) and cell extracts of cultures infected with either type 2 plaque producing agent (ppa) of mdhv or turkey herpesvirus (hvt) (type 2-ag, hvt-ag) had 1 precipitation line in common. hyperimmune sera to the common antigen (common-ag) neutralized to a greater extent by homologous antiserum. absorption of hvt antiserum or hyperimmune serum to type 2 ppa with co ... | 1975 | 167687 |
| influence of vaccination with avirulent herpesvirus on subsequent infection of chickens with virulent marek's disease herpesvirus. | vaccination of chickens with turkey herpesvirus (hvt) or attenuated marek's disease herpesvirus (amdhv) blocked infection with virulent mdhv (vmdhv) for approximately 5 weeks after contact exposure. however, there was no apparent blockage of infection when challenge virus was administered intraabdominally (ia). evidence for infection with vmdhv was based on viral isolation by in vivo assay or by detecting precipitins to "a" antigen associated with virulent virus. the hvt stimulated production of ... | 1975 | 168799 |
| oncogenesis by marek's disease herpesvirus in chickens lacking expression of endogenous (gs, chick helper factor, rous-associated virus-o) and exogenous avian rna tumor viruses. | chickens free of exogenous avian leukosis virus (alv) infection, replicating endogenous alv (rous-associated virus-o), gs antigen, and chick helper factor were fully susceptible to induction of marek's disease (md) by alv-free md viruses. dual infection with rous-associated virus-2 and md virus did not significantly alter the character of the md lesions. thus exogenous alv infection was not requisite for md virus-induced oncogenesis. although participation of endogenous rna tumor virus genes in ... | 1975 | 169364 |
| isolation of marek's disease virus from affected chickens. | | 1975 | 170571 |
| marek's disease--the disease and its prevention by vaccination. | marek's disease (md) is a common lymphoproliferative disease of the domestic chicken caused by a cell associated herpesvirus. vaccines used for the prophylaxis of md have been derived from non-pathogenic field marek's disease virus (mdv), pathogenic mdv and the herpesvirus of turkeys (hvt). vaccines derived from mdv have been developed by attenuation of virus strains which produce the acute form of md and virus strains which produce the classical form. they have also been developed by suitable m ... | 1975 | 170953 |
| immunoglobulins and anti-marek's disease virus antibody synthesis in chickens after passive immunization with immunoglobulin y anti-marek's disease virus antibody. | the effect of passive immunization with immunoglobulin y (igy) antibody against marek's disease virus (mdv) was examined in mdv-susceptible chickens. the production of igy, immunoglobulin m, and probably also immunoglobulin a was depressed in passively immunized chickens when compared with that in mdv-exposed chickens which had not been given igy anti-mdv antibody. in passively immunized chickens, the synthesis of immunoglobulin m and igy anti-mdv antibodies in response to mdv infection also was ... | 1975 | 171985 |
| effect of cyclophosphamide on the response of chickens to a virulent strain of marek's disease virus. | the effect of cyclophosphamide on the pathogenesis of marek's disease was examined in a line of chickens which is relatively resistant to marek's disease. the injection of cyclophosphamide into newly hatched chickens delayed and reduced viremia and also reduced the development of marek's disease lesions until 2 weeks after exposure to marek's disease virus. the data indicate that a population of t cells susceptible to infection with virus and possibly viral transformation is affected by cyclopho ... | 1975 | 172451 |
| responses of isolator-derived japanese quail and quail cell cultures to selected animal viruses. | thirteen oncogenic and necrotizing animal viruses were assayed in life sciences, inc. (lsi)-specific pathogen-free japanese quail and lsi-specific pathogen-free chicken embryo cell cultures. nine viruses produced similar titers in the quail and chicken cell systems, whereas four viruses showed significantly higher titers in chickens. young japanese quail and chickens were inoculated with five selected avain viruses and maintained in stainless-steel isolators. comparable responses were noted in q ... | 1975 | 172527 |
| morphological response of maternal antibody-negative chickens infected with marek's disease virus (mdv), herpesvirus of turkeys (hvt) and both viruses. | | 1975 | 172684 |
| enhancement and interference in chickens inoculated with marek's disease herpesvirus and oncornaviruses. | enhancement of mortality rates and symptomatology was observed in isolator-held lsi-spf chickens concurrently inoculated with mdhv and avian oncornaviruses (rav-1, rav-2, rav-7, rav-50, or rev). interference with md antigen production also was demonstrated in extracts of the feather follicle epithelium from chickens inoculated with both mdhv and rav-1. | 1975 | 174137 |
| effect of in vitro adaptation of marek's disease virus on pock induction on the chorioallantoic membrane of embryonated chicken eggs. | cell-associated preparations of several isolates of marek's disease virus produced more pocks on the chorioallantoic membrane of embryonated chicken eggs than plaques in duck embryo fibroblasts, thus indicating that lesion response in eggs was more sensitive than cytopathic response in duck embryo fibroblasts for assaying low-passage marek's disease virus. adaptation of the virus to cell cultures by serial passages, however, substantially reduced its pock response so that the titer ratio (plaque ... | 1976 | 175018 |
| [pathogenesis of neural lesions in marek's disease. ii. transmission of neural lesions by spleen cells from ill donors (author's transl) ]. | viable spleen lymphocytes of 13 chickens with clinical and histological signs of marek's disease were transferred by intravenous injection to 46 chickens 4-10 days old, x-rayed 24 hours before inoculation. histologically marek-like neural lesions were almost regularly observed in the chickens after 6-14 days. chickens having received destroyed spleen lymphocytes of marek-donors were free of nerve infiltrations. there were also no neural lesions detectable within 14 days after application of path ... | 1975 | 175595 |
| experimental models for dna-rna viral interactions: a brief review. | evidences that demonstrate or imply the occurrence of dna-rna viral interactions in man and animals are reviewed. the concurrent presence of two dissimilar oncogenic viruses influenced responses both in vivo and in vitro. cell-mediated immune responses to marek's disease herpesvirus were altered in specific-pathogen-free chickens inoculated as embryos with an avian leukosis virus. the possible roles of immunological factors in the pathogenesis and control of tumor development associated with dna ... | 1976 | 175924 |
| natural mechanisms of controlling lymphotropic herpesvirus infection (marek's disease) in the chicken. | four categories of natural resistance phenomena against mareks disease in chickens, i.e., maternal antibody, age resistance, genetic resistance, and natural immunization, are described. in nature, these forms of resistance probably act in concert through comlex interrelationships. the mechanisms are not well understood but include humoral immunity (maternal antibody), cell-mediated immunity, and possibly other mechanisms. the possible role of newly discovered tumor-specific antigens in cell-medi ... | 1976 | 175926 |
| effect of phosphonoacetate on marek's disease virus replication. | phosphonoacetate (pa), but not any of its analogues tested, effectively inhibited avian herpesvirus replication and viral dna synthesis in cell cultures. at 100 mug/ml culture medium, pa completely inhibited the replication of marek's disease virus (mdv), herpesvirus of turkeys, and owl herpesvirus, but had no measurable effect on normal cell growth. pa also inhibited dna polymerases induced by these avian viruses. enzyme inhibition was 50% at a pa concentration of 0.2 mug/ml. at a concentration ... | 1976 | 176410 |
| marek's disease in chickens: development of viral antigen in feather follicles and of circulating antibodies. | the infection of young chickens with marek's disease herpesvirus (mdhv) leads to the early appearance of viral antigen in the bursa fabricii, in the kidney tubular epithelium, and particularly in the epithelial cells of growing feather follicles (calnek and hitchner, 1969; purchase, 1970). viral antigen may persist in feather follicles over several months, whereas in neural lesions or in lymphoid tumors induced by mdhv viral antigen is either lacking or present only in a few cells (calnek and hi ... | 1976 | 179946 |
| marek's disease in japanese quail -- a pathological, virological and serological study. | experimental studies were performed to see whether japanese quail (coturnix coturnix japonica) are susceptible to jm strain of marek's disease virus (mdv). in three identical trials, a total of 120, one-day-old quail were inoculated intra-abdominally with 0.2 ml. of chicken blood infected with mdv (jm strain) and raised in fapp isolators. uninfected controls were inoculated with normal saline only and raised separately. during the 18-week post infection observation period, 65-80% of the infecte ... | 1975 | 180503 |
| cyclophosphamide-induced amelioration of marek's disease in marek's disease-susceptible chickens. | bursa- and thymus-dependent functions were examined in marek's disease (md)-susceptible normal chickens and in chickens treated with 5 and 16 mg of cyclophosphamide (cy) at the time of hatching. chickens not exposed to marek's disease virus (mdv) and treated with cy temporarily lost mitogenic response to concanavalin a but regained full response after 5 weeks. bursa-dependent functions, such as presence of germinal centers in spleen and cecal tonsils, morphologic features of bursa, and sheep red ... | 1976 | 180852 |
| a possible association between plaque type and pathogenicity of marek's disease herpesvirus. | eighteen isolants of marek's disease herpesvirus (mdhv) were examined for their plaque types in chicken embryo fibroblast cell cultures and their pathogenicity to an experimental line of white leghorns highly susceptible to md. seven isolants (id-1, ga, wsu-gf, and 4 field isolants) induced morphologically similar small-cell plaques (sc plaques) consisting of small round refractile cells, whereas 11 isolants (hn and 10 isolants from zoo birds) all induced large-cell plaques (lc plaques) containi ... | 1976 | 180958 |
| [effectiveness of a bulgarian vaccine against marek's disease in broilers]. | studies were carried out to establish the effectiveness of the immunization of broilers against marek's disease using a bulgarian vaccine produced with strain c3-1 of a turkey herpes virus. the experiments were done under the conditions of an industrial poultry dressing combine with a total of 52,450 day-old hybrid birds vaccinated at the rate of 1000 plaque-forming units (pfu), 39,450 birds vaccinated with 500 pfu each, and 91,564 unvaccinated control birds. after the 60-63-day fattening period ... | 1976 | 181895 |
| [differentiation of antibodies against turkey herpesvirus and 2 serotypes of marek's disease virus in the sera of farm chickens]. | | 1976 | 183416 |
| marek's disease vaccine breaks: differences in viremia of vaccinated chickens between those with and without marek's disease. | viremia with turkey herpesvirus (hvt) and/or marek's disease (md) herpesvirus (mdhv) was examined in chickens from three different commercial flocks experiencing "vaccine breaks" following vaccination with hvt vaccine against md. in all groups of sample chickens from the flocks, the incidence of detectable hvt viremia was significantly less in the md-affected than in the healthy penmates, and incidence of md was significantly higher in the birds without detectable hvt viremia than in the viremic ... | 1976 | 183650 |
| marek's disease: epizootiology, control and relationship to oncornaviruses. | | 1975 | 183670 |
| the role of herpesviruses in marek's disease lymphoma of chickens. | | 1976 | 185662 |
| turkey herpesvirus infection in chickens: induction of lymphoproliferative lesions and characterization of vaccinal immunity against marek's disease. | chickens vaccinated at hatching with high doses of turkey herpesvirus (hvt) developed viremia that peaked in titer around the 12th day and gradually declined. hvt infection also induced mild microscopic lymphoproliferative lesions in the nerves and gonads. these lesions were most prominent around the 12th day and then regressed. the fact that such lesions were also induced by hvt in cyclophosphamide-treated chicks suggests that they were t-cell-dependent. some of the cells in early hvt lesions a ... | 1976 | 186008 |
| [methods for the control of avian tumour virus diseases (author's transl)]. | methods developed in the netherlands for the control of avian tumour virus diseases, marek's disease and lymphoid leukosis, are discussed. marek's disease is successfully kept under control by vaccination of all day-old chickens raised for egg production. broilers are not vaccinated. during 1975 over 23 million chicks were vaccinated with cell-associated marek's disease virus cvi 988 vaccines and about 3 million doses of hvt vaccine were administered, mostly in lyophilised form. the mechanism of ... | 1977 | 189455 |
| marek's disease virus dna in a chicken lymphoblastoid cell line (msb-1) and in virus-induced tumours. | | 1975 | 191363 |
| isolation from a transmissible lymphoid tumour (tlt) lymphoblastoid cell line of a herpesvirus similar to marek's disease virus. | a chicken lymphoblastoid cell line (tlt)-6855 originally established from an avian oncornavirus-induced lymphoma (siegfried and olson, 1972) was studied for the presence and expression of marek's disease virus (mdv) genome. by nucleic acid hybridization a significant amount of mdv dna was found in this cell line. this virus dna, however, was not expressed in either virus-specific intracellular or membrane antigens or the md-associated tumour-specific surface antigen (matsa). moreover, mdv-specif ... | 1977 | 191411 |
| [effect of izatizon and ol-56 on the reproductive and transformational properties of marek's disease virus]. | | 1977 | 191986 |
| rejectability of virus-induced tumors and nonrejectability of spontaneous tumors: a lesson in contrasts. | in contrast to the excellent surveillance against tumors induced by the ubiquitous viruses in their natural host species, spontaneous tumors developing naturally, without experimental interference, evoke little or no rejection reaction. this may be viewed in relation to the natural history of tumors. in most cases, tumors evolve in several steps, with a successful of clonal variants following each other, characterized by increasing independence of host regulations (including immune restrictions) ... | 1977 | 194366 |
| lymphoproliferative diseases of fowl: jm-v leukemic lymphoblasts in cell culture. | jm-v leukemic lymphoblasts were established in cell culture. the cultured cells (jm-vlc cells) were transplantable in young chicks and produced a disease indistinguishable from jm-v lymphoblastic leukemia as initiated by whole-blood inoculation. jm-vlc cells maintained a normal female karyotype through 13 passages in rhode island red cockerels. with the use of jm-v antisera and antisera from birds with naturally occurring marek's disease (md), specific antigens were detected on the surfaces of l ... | 1977 | 195070 |
| isolation and identification of marek's disease virus by fluorescent antibody technique. | cell-associated herpesvirus related to marek's disease (md) was isolated from the direct culture of kidney cells of naturally infected chickens at taoyuan or by inoculation of clinical specimens to chick kidney (ck) and chick embryo fibroblast cells. the virus isolates replicated in ck or chick embryo kidney cell cultures were identified to be md by the fluorescent-antibody technique. | 1976 | 196818 |
| dissociation of antiviral and antitumor immunity in resistance to marek's disease. | immunization of chickens either with gluteral-dehyde-inactivated chicken kidney cells infected with marek's disease (md) virus or with glutaraldehyde-inactivated cells of md lymphoma-derived continuous lymphoblastoid cell lines protected against md. the former type of immunity was associated with an immunologic suppression of virus replication and virus antigen production after challenge with virulent virus, but lymphocytes specifically cytotoxic to cells bearing md tumor antigens were not detec ... | 1977 | 197249 |
| [mechanism of postvaccinal immunity in marek's disease]. | the apathogenic variant no. 38 of marek's disease virus, kekava strain (mdv-kekava), at the level of the 16th and 45th passages in vitro made chickens resistant to marek's disease when inoculated 14 days before the infection of the chickens with the pathogenic variant no. 55 of mdv-kekava. a simultaneous administration of both variants did not protect the animals against the disease. the occurrence in variants of mdv-kekava of genetic markets manifest upon virus passages in chick embryo fibrobla ... | 1977 | 198968 |
| isolation of marek's disease herpesvirus of low pathogenicity from commercial chickens. | | 1977 | 201237 |
| pathological changes in chickens inoculated with reticuloendotheliosis-virus-contaminated marek's disease vaccine. | a disease characterized by delayed growth, anemia, abnormal feathers, and leg paralysis occurred among chickens inoculated with marek's disease vaccine over a period from spring to fall in 1974. these chickens were recognized among flocks inoculated with the vaccine produced by two vaccine makers. the affected ones were examined pathologically. gross examination revealed a slight enlargement of peripheral nerves and atrophy of the spleen, thymus, and bursa of fabricius. histopathologically, the ... | 1977 | 203872 |
| dual virus maturation of both pathogenic and apathogenic marek's disease herpesvirus (mdhv) in the feather follicles of dually infected chickens. | infectious cell-free viruses of both pathogenic and apathogenic marek's disease herpesvirus (mdhv) were detected in feather-tip extracts of chickens dually infected with both mdhv isolants either by inoculation or by contact exposure. this indicated concurrent viral maturation of both pathogenic and apathogenic mdhv isolants in the feather-follicle epithelium, resulting in possible double shedding of the two isolants. | 1977 | 204277 |
| contrasting characteristics of marek's disease herpesvirus isolated from chickens with and without avian leukosis virus infection. | marek's disease herpesvirus (mdhv) isolated from chickens free of naturally occurring avian leukosis virus (alv) infection produced characteristic foci in both chicken embryo fibroblast (cef) and chicken kidney cell (ckc) cultures. mdhv-a, which was extracted from the feather follicle epithelium of chickens naturally infected with alv, did not induce cytologic changes in cef cultures, but did cause focus formation in ck cultures. alv was detected in mdhv-a, but not in mdhv preparations. mdhv-a ( ... | 1978 | 204600 |
| in vitro establishment of marek's disease herpesvirus-transformed productive and nonproductive lymphoblastoid cell lines. | the establishment of two marek's disease herpesvirus-transformed lymphoblastoid cell lines (jmv-1 and jm-1) is reported. cocultivation with chicken embryo fibroblasts, attempts to rescue marek's disease virus from kidney cell cultures, and immunofluorescent staining show that jmv-1 is a nonproductive line and jm-1 is a productive line. | 1978 | 208974 |
| vaccination immunity to selected diseases in chickens fed the androgen analog mibolerone. | chickens fed the androgen analog mibolerone during the first 7 weeks of life regress their bursa of fabricius but can be properly immunized by vaccination against avian pathogens of major economic importance such as newcastle disease virus, infectious laryngotracheitis virus, avian encephalomyelitis virus, infectious bronchitis virus, fowl pox virus, marek's disease virus, and pasteurella multocida, the pathogen causing fowl cholera. these findings on immunocompetence to infectious agents are im ... | 1978 | 209430 |
| a comparative pathogenesis of two mareks disease virus isolates. | the pathogenesis of the jm and ga isolates of marek's disease virus (mdv) infection was compared by studying the sequential tissue distribution of mdv associated antigens with gross and microscopic lesions in infected chickens. with both mdv isolates the initial sites of viral replication were the lymphoid organs, skin, and featers. both the ga and jm isolates were viscerotropic as demonstrated by the presence of mdv antigens with gross and microscopic changes occurring in several visceral organ ... | 1978 | 209437 |
| [testing the immunogenicity of the dermal antigen in marek's disease virus]. | an experiment was performed to study the immunogenicity of the dermal antigen of marek's disease virus, extracted from the skin of 30-day-old chickens, infected with marek's disease virus on the first day of life. three kinds of samples were tested: (1) dermal antigen centrifuged at 10 000 g per 0.5 h, (2) dermal antigen centrifugated at 10 000 g per 0.5 h and 100 000 g per 1 h, (3) dermal antigen treated like sample (2) and partly purified by deae-cellulose chromatography. samples (1) and (2) w ... | 1978 | 209603 |
| biochemical evidence of the nonintegrated status of marek's disease virus dna in virus-transformed lymphoblastoid cells of chicken. | | 1978 | 209622 |
| [immunogenic activity of vaccines against marek's disease]. | | 1978 | 210559 |
| suppression and enhancement of mitogen response in chickens infected with marek's disease virus and the herpesvirus of turkeys. | the kinetics of phytohemagglutinin (pha) response of peripheral blood lymphocytes from chickens infected with oncogenic marek's disease (md) virus (mdv) or nononcogenic herpesvirus of turkeys (hvt) was studied with a whole blood microassay. at about 7 days after inoculation, a depression in pha response was observed in mdv-inoculated resistant line n or susceptible line 7(2) chickens and in hvt-inoculated line 7(2) chickens. all chickens initially regained their pha responsiveness. susceptible c ... | 1978 | 211085 |
| demonstration of marek's disease tumor-associated surface antigen in chickens infected with nononcogenic marek's disease virus and herpesvirus of turkeys. | the presence of marek's disease tumor-associated surface antigen (matsa) was demonstrated on spleen cells from p-line chickens inoculated 5--6 days earlier with herpesvirus of turkeys and sb-1 (a nononcogenic marek's disease virus). antisera against matsa expressed on five marek's disease lymphoblastoid cell lines were able to recognize the matsa present on sb-1-infected spleen cells. no viral membrane antigens and only a low incidence of viral internal antigens could be demonstrated. | 1978 | 211242 |
| lymphoproliferative diseases of fowl: characterization of transplantable g-b1 marek's disease tumor cells in culture. | a transplantable marek's disease tumor, derived and maintained through in vivo passage in syngeneic g-b1 chickens, was established in cell culture and characterized. the cells (gbt cells) grew in suspension and appeared morphologically similar to other marek's lymphoblastoid lines except for prominent nucleoli in gbt cells. the number of chromosomes increased during in vitro cultivation from near triploid to subtetraploid. chromosome no. 3 was abnormally short. the gbt cells retained surface b1 ... | 1978 | 212000 |
| development of cell-mediated immunity to marek's disease tumor cells in chickens inoculated with marek's disease vaccines. | chickens inoculated with herpesvirus of turkeys or with apathogenic or attenuated vaccine strains of marek's disease virus (mdv) developed a t-cell-mediated immune response to marek's disease (md) tumor cells. this immune response was detected in a 4-hour 51cr-release assay in which effector cells obtained from spleens of vaccinated chickens were reacted with 51cr-labeled target cells of an md lymphoblastoid cell line (msb-1). the cytotoxic effector cells generated by the vaccine viruses had cha ... | 1978 | 213610 |
| nonprotective and temperature-sensitive variants of marek's disease vaccine viruses. | | 1979 | 214607 |
| protection against marek's disease-derived tumor transplants by the nononcogenic sb-1 strain of marek's disease virus. | a series of experiments was conducted to study the in vivo protection against marek's disease-derived tumor transplants by the nononcogenic sb-1 strain of marek's disease virus. intact, embryonally bursectomized (bx), thymectomized (tx), or cyclophosphamide (cy)-treated chickens of four genetic lines were vaccinated with live or inactivated sb-1. jmv, a non-virus-producing transplant, and ga/tr-1 and mdt-198, two virus-producing transplants were used for challenge. optimal protection against jmv ... | 1978 | 215543 |
| enhanced oncornavirus expression in marek's disease tumors from specific-pathogen-free chickens. | an oncornavirus was recovered from cell cultures of kidney tumors from specific-pathogen-free chickens inoculated with marek's disease herpesvirus (mdhv). the mdhv inoculum was free of infectious avian leukosis virus (alv). direct examination of a variety of tissues from mdhv-inoculated chickens demonstrated increased levels of alv-specific rna compared to tissues from diluent-inoculated (control) chickens. dna from cultured kidney tumor cells annealed to an alv complementary dna probe at the sa ... | 1979 | 216833 |
| [experiments with the simultaneous or combined vaccination of chicks against marek's disease and newcastle disease]. | simultaneous vaccination was carried out of day-old chicks against marek's disease (strain c3--1) and newcastle disease (strains b1 and la sota) which did not prove to be effective in conferring a lasting immunity to newcastle disease though it was tolerated without any disturbances whatever. one could resort to it by way of an exception only, with an obligatory revaccination 15 days later, when the unfavourable epizootic status made it necessary. the immunity built up against marek's disease di ... | 1978 | 219586 |
| transcription of the marek's disease virus genome in a nonproductive chicken lymphoblastoid cell line. | | 1979 | 219594 |
| effectiveness of cell-free or cell-associated turkey herpesvirus vaccine against marek's disease in chickens as influenced by maternal antibody, vaccine dose, and time of exposure to marek's disease virus. | | 1978 | 219826 |
| in vitro inactivation of cell-free marek's disease herpesvirus by immune peripheral blood lymphocytes. | the effect of peripheral blood lymphocytes (pbl) on cell-free marek's disease virus (mdv) was studied in vitro in pbl from intact or embryonal bursectomized (bx) chicks infected with the apathogenic sb-1 isolate of mdv. the pbl were harvested purified and were mixed, 200 or 2,000 to 1, with cell-free ga-5 of mdv. virus survival was assayed after incubation for 1 hour at 36 c by the standard assay for cell-free mdv. pbl from intact but not bx chickens were able to inactivate virus. when the effec ... | 1978 | 219833 |
| status of endogenous avian rna tumor virus in marek's disease lymphoblastoid cell lines and susceptibility of those lines to exogenous rna tumor viruses. | three lymphoblastoid cell lines from marek's disease (md) tumors, two md virus (mdv) producer lines (msb-1 and hprs-1), and a nonproducer line (rpl-1) were studied for the expression of avian leukosis sarcoma (als) viruses. the msb-1 line was free of all known endogenous expressions, including replicating virus (rav-o), group-specific (gs) antigens, and chick helper factor (chf). the rpl-1 and hprs-1 were positive for gs antigens and chf. the rpl-1 and msb-1 lines showed no evidence of an exogen ... | 1978 | 219836 |
| non-protective variants of marek's disease vaccine viruses. | two variant marek's disease-vaccine viruses failed to induce protective immune responses in chickens and replicated poorly in vivo. one of these, mdv/200d, was defective for growth at 41 degrees c, and clones from this stock had 38 degrees c/41 degrees c plating ratios as high as 10(4). the basis for the poor in vivo replicative ability was not determined. | 1978 | 221372 |
| transfection studies in vitro and in vivo with isolated marek's disease virus dna. | for tranfection studies in vitro and in vivo, infectious marek's disease virus (mdv) dna was isolated from purified virus particles. its sedimentation coefficient in neutral sucrose gradients was found to be 53 +/- 2s and the buoyant density in caesium chloride corresponded to 1.707 g/cm3. the virus dna was also analysed by using the restriction endonucleases ecori and hindiii. high molecular-weight mdv dna precipitated by the calcium phosphate technique was shown to be infectious in cultivated ... | 1978 | 221387 |
| expression of marek's disease virus in producer and non-producer lymphoblastoid cell lines. | continuous in vitro propagation of a producer marek's disease (md) lymphoblastoid cell line reduced the number of cells producing virus antigens and the inducibility of these antigens to 5-iododeoxyuridine (iudr) but did not change the oncogenicity of the cells for chickens. in contrast, propagation of a non-producer md cell line did not change the non-productivity of the cell line, but decreased the transplantability of the cells. the md lines were free of replicating avian leukosis sarcoma vir ... | 1978 | 221388 |
| the role of the macrophages in marek's disease: in vitro and in vivo studies. | macrophages form s- and k-strain leghorn chickens, susceptible and restant to marek's disease (md) respectively, were studied to determine the macrophage contribution to the dynamics of md infection, tumorigenesis and genetic resistance to this disease. in vitro studies demonstrated that macrophages from bothstrains were similar in their responses toward jm strain of marek's disease virus (mdv) and jm-1 tumor cells. macrophages were observed to phagocytize jm virus, but the interiorized virus wa ... | 1979 | 222692 |
| expression of genetic resistance to an oncogenic herpesvirus at the target cell level. | | 1979 | 223067 |
| infection studies on a reticuloendotheliosis virus contaminant of a commercial marek's disease vaccine. | reticuloendotheliosis virus (rev) was isolated in cell cultures from commercial marek's disease (herpesvirus of turkeys) vaccine and re-isolated from the organs of vaccinated chickens. runting and feathering abnormalities were produced when 1-day-old specific pathogen free chickens were inoculated with rev. histopathological lesions in infected chickens were hypoplasia of the thymus, bursa and spleen, and inflammation of the proventriculus, kidneys and liver. serological responses to rev were de ... | 1979 | 223539 |
| induction of virus-neutralizing antibody by glycoproteins isolated from chicken cells infected with a herpesvirus of turkeys. | the production of virus-induced proteins in chicken embryo fibroblast cells infected with a herpesvirus of turkeys was studied. it was found that glycoproteins isolated from membrane-rich fractions of infected cells by affinity chromatography using concanavalin a induced neutralizing and precipitating antibody in rabbits and chickens. after analytical electrophoresis, such isolates were found to contain three polypeptide bands of between 100 x 10(3) and 120 x 10(3) molecular weight not present i ... | 1979 | 225277 |
| transcription of the marek's disease virus genome in virus-induced tumors. | transcription of the marek's disease virus (mdv) genome in tumor tissues from mdv-infected chickens has been studied by analyzing the hybridization kinetics of (3)h-labeled mdv dna with unlabeled rna extracted from these tissues. lymphoid tumors of ovary, spleen, liver, and kidney contained mdv genomes, but the virus-specific rna sequences were transcribed from less than 15% of the viral dna. a virus nonproductive lymphoblastoid cell line, designated mkt-1, has been established from a kidney lym ... | 1979 | 225531 |
| inhibitory effects of macrophages against marek's disease virus plaque formation in chicken kidney cell cultures. | inhibition of plaque formation by marek's disease virus (mdv) in chicken kidney cell cultures was investigated with the use of peritoneal exudate cells (pec) from chickens. pec from mdv-infected white leghorn chickens inhibited the formation of mdv plaques, whereas the inhibitory effect of pec from chickens vaccinated with herpesvirus of turkey (hvt) or pec from normal chickens was very weak. however, pec from either normal chickens or hvt-vaccinated chickens inhibited the mdv plaque formation i ... | 1979 | 228107 |
| replication of turkey herpesvirus and marek's disease virus in chick embryo skin organ culture. | turkey herpesvirus (hvt) and an attenuated marek's disease virus (mdv) replicated in organ cultures of chick embryo skin as assessed by immunofluorescence and/or electron microscopy. hvt-specific immunofluorescent antigen was detected in the feather follicle epithelium (ffe) and in the surface layer of the skin epidermis. electron microscopy of infected explants revealed herpes-type cytopathology. immature particles of both viruses appeared first in the nucleus. oval or horseshoe-shaped non-enve ... | 1979 | 228368 |
| marek's disease lymphoma of chicken and its causative herpesvirus. | | 1979 | 228727 |
| turkey herpesvirus and marek's disease virus. a comparative appraisal. | | 1979 | 228905 |
| comparative pathogenesis studies with oncogenic and nononcogenic marek's disease viruses and turkey herpesvirus. | an apparently nononcogenic marek's disease virus (sb-1) and turkey herpesvirus could be readily isolated from spleen, bursa of fabricius, thymus, and peripheral blood lymphocytes of chickens beginning 4 to 6 days after inoculation, but unlike infections with two isolates of oncogenic marek's disease virus (jm-10 and cu-2), virus replication in these cells was rare, and necrosis in the organs was essentially absent. splenic enlargement was observed regularly during the first 4 to 11 days after in ... | 1979 | 229747 |
| intracellular state of marek's disease virus dna in two tumour-derived chicken cell lines. | | 1979 | 230282 |
| comparative studies on marek's disease virus and herpesvirus of turkey dnas. | dna of marek's disease virus (mdv) was compared to that of herpes virus of turkey (hvt). centrifugation of the two virus dnas in neutral glycerol and cscl density gradients showed that the mdv genome was slightly larger than that of hvt and that the buoyant density (1.705 g/ml) of mdv dna in cscl gradients was slightly lower than that (1.707 g/ml) of hvt dna. mdv and hvt dnas were digested with either ecori or hindiii restriction endonuclease and analysed by 0.5% agarose gel electrophoresis. the ... | 1979 | 230299 |
| marek's disease in chickens: correlation of marek's disease with nuclear-inclusion formation in feather-follicle epithelium. | the dynamics of nuclear-inclusion (ni) formation in feather-follicle epithelium of chickens inoculated with marek's disease virus (with or without prior immunization with turkey herpesvirus) could be divided into two patterns: 1) transient ni formation at the initial stage postchallenge; and 2) persistent ni formation. incidence of marek's disease was closely correlated with the dynamics of ni formation. active ni formation recurred in chickens showing pattern 2 and was closely related to the in ... | 1979 | 230801 |
| low incidence of lymphoid tumors in chickens continuously producing endogenous virus. | a flock of 258 male and 243 female chickens of a cross of regional poultry research laboratory lines 15b and 7(2) were kept in a filtered-air positive-pressure house and observed for tumors from 100 to more than 729 days of age. these birds produced high titers of a subgroup e endogenous virus from the middle of the embryonic incubation period through the end of the experiment. no neoplasms were observed in the males. the females had two neoplasms indistinguishable from lymphoid leukosis and thr ... | 1979 | 230806 |
| effect of culture temperature on the production of marek's disease virus antigens in a chicken lymphoblastoid cell line. | | 1979 | 231431 |
| establishment of marek's disease lymphoblastoid cell lines from chickens with babk of b blood groups. | | 1979 | 231432 |
| marek's disease virus and herpesvirus of turkey noninfective to chickens, obtained by repeated in vitro passages. | the relation between the passage level of marek's disease virus, c2 strain, and of herpesvirus of turkey (hvt), o1 strain, in cell culture and the level of the serological response of chickens to these viruses was examined. in both cases the immune response of chickens to these viruses decreased with increase in the number of in vitro passages of virus. virus was not recovered from chickens inoculated with hvt highly passaged in vitro, which had become a high producer of cell-free virus in vitro ... | 1979 | 231437 |
| increased agglutinability and haemadsorption of marek's disease hprs line 1 lymphoblastoic cells after concanavalin a treatment. | the hprs line 1 lymphoblastoid cells derived from an ovarian lymphoma induced by marek's disease virus in chickens displayed increased agglutinability and haemadsorption when incubated with con a. the increase was proportional to the concentration of con a used. the same con a-untreated cells and normal chicken lymphocytes incubated with con a exhibited no increase in agglutinability and haemadsorption, however. | 1979 | 231521 |
| pathogenesis of marek's disease; effect of immunization with inactivated viral and tumor-associated antigens. | inactivated marek's disease virus-infected chicken kidney cells and inactivated msb-1 lymphoblastoid marek's disease tumor cells were used to immunize chickens as virus- and tumor-associated antigens, respectively. immune and nonimmune birds were then challenged by exposure to live virulent marek's disease virus. both vaccines protected significant numbers of chickens (p less than 0.05) against subsequent tumor development, although viral antigen appeared superior to tumor antigen. after challen ... | 1979 | 232690 |
| marek's disease virus (kekava strain) replication in chickens, chick embryos and cell cultures. | in the course of 12 passages of marek's disease virus (mdv) strain kekava (mdv-kekava) in chickens, the morbidity varied greatly (from 23 to 50 percent). mdv-kekava produced plaques in cultures of chick embryo kidney and adult chicken kidney cells and chick embryo fibroblasts (cef). the virus adaptation to the cultures was very slow. mdv-kekava induced the formation of pocks on the chorioallantoic membranes (cam) of chick embryos but the proportion of embryos with cam lesions did not exceed 24 p ... | 1975 | 241226 |
| atheroarteriosclerosis induced by infection with a herpesvirus. | atheroarteriosclerosis closely resembling that in humans was induced in normocholesterolemic and hypercholesterolemic chickens by infection with marek's disease herpesvirus (mdv). four comparably sized groups of chickens were used. each group was initially fed a diet relatively poor in cholesterol. group i and ii were inoculated intratracheally at 2 days of age with mdv. at 15 weeks, one group of virus-infected chickens (group ii) and one group of uninfected controls (group iv) were fed a 2% cho ... | 1979 | 382868 |
| effects of vaccination for marek's disease on growth of a marek's-virus-induced transplantable lymphoma in syngeneic and allogeneic chickens. | a study was made of the effects of vaccination with turkey herpesvirus on the growth of tumors following inoculation of lymphoma cells induced by marek's disease virus (mdv). the cells used were from a transplantable mdv-induced lymphoid tumor (mdt-198) maintained by passaging in syngeneic hosts. vaccination did not prevent progressive tumor growth or alter subsequent mortality among syngeneic recipients of mdt-198 cells. with allogeneic recipients, however, vaccination had a significant protect ... | 1979 | 486007 |
| serum protein changes in chickens with experimental marek's disease. | serum protein alterations in chickens contact-exposed to marek's disease virus (mdv) were studied by crossed immunoelectrophoresis. total protein values of infected chickens were initially, i.e. in the 4th week, low and later not significantly changed from those of the controls. in all infected chickens a significant increase was seen in the igg components. three of 6 infected chickens showing a prolonged period of clinical illness presented the most pronounced changes in other serum proteins, m ... | 1979 | 523311 |
| pathogenicity of a marek's disease virus for chickens vaccinated with graded doses of herpesvirus of turkeys. | six different groups of one-day-old chickens were vaccinated with herpesvirus of turkeys (hvt) vaccine at doses of 0, 4, 16, 64, 256 and 1,024 plaqueforming units. at 9 days of age they were challenged with an acute strain of marek's disease herpesvirus (mdhv). gross and microscopic lesions in nerves and gonads were investigated and combined for quantitative expression of mdhv pathogenicity. including the microscopic lesions improved the accuracy of the hvt doses/mdhv response. the qualitative a ... | 1979 | 546406 |
| isolation and characterisation of herpes virus from turkeys. | turkey herpesvirus (hvt) was isolated from the kidneys of 6 of 8 turkey poults from two flocks. the isolates were identified by syncytial-type of cytopathology, inhibition of plaque formation by 5-bromodeoxyuridine, formation of cowdry type a intranuclear inclusions in cell cultures, and presence of herpes-type virions in negatively stained preparations and thin sections of infected cell cultures. one of these isolates inoculated into chickens proved apathogenic over an observation period of 10 ... | 1977 | 614022 |