Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| feline leukaemia virus testing. | 1981 | 6278376 | |
| feline leukemia: a naturally occurring cancer of infectious origin. | 1982 | 6291969 | |
| selective effect of feline leukaemia virus on early erythroid precursors. | 1982 | 6278316 | |
| nucleotide sequences of feline retroviral oncogenes (v-fes) provide evidence for a family of tyrosine-specific protein kinase genes. | the nucleotide sequences encoding the transforming polyproteins of the snyder-theilen and gardner-arnstein strains of feline sarcoma virus (fesv) have been determined. these sequences include a viral transforming gene (v-fes), derived from cellular proto-oncogene sequences (c-fes) of domestic cats by recombination with feline leukemia virus (felv). the v-fes sequences are predicted to encode a polypeptide domain strikingly similar to that specified by the transforming gene (v-fps) of the avian f ... | 1982 | 6183005 |
| detection of transient and persistent feline leukaemia virus infections. | a study was made of cats persistently or transiently viraemic with feline leukaemia virus (felv) following experimental oronasal infection. cats of two ages were exposed to the virus. one group was infected when eight weeks old in the expectation that most of the cats would become persistently viraemic, and the second group when 16 weeks old, so that some would show signs of a transient infection and then recover. the periods following infection when virus was detectable in the blood and in the ... | 1982 | 6281958 |
| monoclonal antibodies to three epitopic regions of feline leukemia virus p27 and their use in enzyme-linked immunosorbent assay of p27. | three different monoclonal antibodies were developed against the major core protein (p27) of feline leukemia virus (felv). each antibody was directed against a different epitope of the species-specific portion of felv-p27. the 3 antibodies reacted with 5 different isolates of felv but not with 7 other retroviruses (mulv (rauscher), mulv (akr), mpmv, mmtv, smrv, baev, rd 114). these monoclonal antibodies could readily be adapted to an enzyme-linked immunosorbent assay (elisa) for the specific mea ... | 1983 | 6186744 |
| effects of retrovirus protein on the feline one-way mixed leukocyte reaction. | the objective of this study was to evaluate the effects of feline retrovirus protein on cat lymphocyte recognition of allogeneic cells in the mixed leukocyte reaction (mlr), using u.v.-inactivated feline leukaemia virus (felv) and a non-disease-producing endogenous cat virus (rd-114). twenty micrograms of u.v.-inactivated virus protein from each virus were added to mixed leukocyte cultures. felv induced significant suppression of the mlr (p less than 0.005) whereas no significant suppression was ... | 1983 | 6300313 |
| erythrocyte macrocytosis in feline leukemia virus associated anemia. | using erythrocyte volume distribution histograms (erythrograms), erythrocyte macrocytosis and anisocytosis were quantitated in 139 cats tested for feline leukemia virus group-specific antigen. feline leukemia virus-negative cats with non-regenerative anemia or normal packed cell volumes had normal mean corpuscular volume values. uninfected cats with regenerative anemia had prominent significantly increased macrocytosis and anisocytosis (p less than 0.01). ninety percent of 62 feline leukemia vir ... | 1983 | 6316617 |
| molecular cloning and characterization of endogenous feline leukemia virus sequences from a cat genomic library. | recombinant bacteriophage lambda clones from a cat genomic library derived from placental dna of a specific pathogen-free cat were screened to identify endogenous feline leukemia virus (felv) sequences. restriction endonuclease mapping of four different clones indicates that there are a number of similarities among them, notably the presence of a 6.0- to 6.4-kilobase pair (kbp) ecori hybridizing fragment containing portions of sequences homologous to the gag, pol, env, and long terminal repeat-l ... | 1983 | 6304345 |
| characterization of the expression of cellular retrovirus genes and oncogenes in feline cells. | expression of endogenous retrovirus genes and two different cellular oncogenes (c-onc genes) was examined at the transcriptional level in a variety of normal and lymphoma/leukemia tissues of the domestic cat. the two oncogenes, c-myb(related to avian myeloblastosis virus) and c-myc(related to avian myelocytomatosis virus) were selected for their association with the induction of hematopoietic malignancies, when present in the transforming retroviruses. tissue-specific expression of endogenous fe ... | 1983 | 6329934 |
| retroviruses in human leukemia. | after decades of work, a retrovirus of true human origin has been isolated first from a u.s. adult case of t-cell lymphoma and then from cases from various regions of the world. this virus, named htlv-i, is strongly associated with a malignant leukemia-lymphoma of mature t-cells. this disease was first clinically characterized in japan but subsequently found to cluster in the caribbean region, areas of the u.s. and in other countries. this retrovirus-associated malignancy has an adult onset and ... | 1983 | 6329935 |
| characterization of a differentiated cat melanoma cell line. | we have established several long-term cultures of a naturally occurring metastatic melanoma of a domestic cat. the cells are fully differentiated as indicated by the fontana-masson staining of the melanin in the perinuclear region and by electron microscopy of the cytoplasmic melanosomes in various stages of development. the melanoma cells do not produce virus particles or the major core proteins (i.e., protein with a molecular weight of 30,000) of the feline leukemia virus or the endogenous cat ... | 1983 | 6850643 |
| clearance of feline leukemia virus from persistently infected pet cats treated by extracorporeal immunoadsorption is correlated with an enhanced antibody response to felv gp 70. | six persistently feline leukemia virus (felv)-infected pet cats were treated by extracorporeal immunoadsorption with staphylococcus aureus cowan i (sac) to remove circulating immune complexes and immunoglobulin g (igg) from plasma. in three of these cats, the felv infection was eliminated, whereas in the other three cats the infection persisted. the amounts of peripheral blood leukocyte (pbl)-associated felv, soluble felv envelope glycoprotein (gp70) antigens in serum, and felv-gp70-specific ant ... | 1984 | 6319496 |
| indirect leukocyte migration inhibition in breast cancer and benign breast disease patients by mouse mammary tumor virus grown in feline kidney cells. | indirect migration inhibition assays were performed with normal and mammary tumor-bearing c3h/hen mice and patients with breast disease to assess cellular immunity against three different mouse mammary tumor virus (mtv) preparations grown in feline kidney cell cultures and against a mouse-derived mtv preparation. mtv obtained after passage through feline kidney cells and the mouse-derived mtv were capable of eliciting macrophage migration inhibitory factor production by mouse spleen cells obtain ... | 1984 | 6321840 |
| a new package for an old oncogene. | 1984 | 6325919 | |
| nucleotide sequence of the gag gene and gag-pol junction of feline leukemia virus. | the nucleotide sequence of the gag gene of feline leukemia virus and its flanking sequences were determined and compared with the corresponding sequences of two strains of feline sarcoma virus and with that of the moloney strain of murine leukemia virus. a high degree of nucleotide sequence homology between the feline leukemia virus and murine leukemia virus gag genes was observed, suggesting that retroviruses of domestic cats and laboratory mice have a common, proximal evolutionary progenitor. ... | 1984 | 6328019 |
| appearance of cytotoxic antibody to viral gp70 on feline lymphoma cells (fl-74) in cats during ex vivo immunoadsorption therapy: quantitation, characterization, and association with remission of disease and disappearance of viremia. | fifty cats with feline leukemia virus (felv) infection and leukemia-lymphoma complex were treated by ex vivo immunoadsorption with staphylococcus protein a-bound filters. most cats responded to therapy. twelve showed tumor regression, including disappearance of tumor cells, but died later of other complications. three have had long-term remission of more than 1 year and remain healthy. a consistent finding in these three cats was the appearance during treatment of a complement-dependent cytotoxi ... | 1984 | 6328520 |
| [infection with feline leukemia virus: immunology and serodiagnosis as a basis for the prevention of infection. 2]. | 1984 | 6324338 | |
| [clinical aspects of infection with feline leukemia virus in cats]. | the leukemia-sarcoma complex constitutes the most common group of malignancies in the cat. epizootiology of felv infections and pathogenesis, which can be divided into three stages, are described. diagnosis can be made by immunofluorescent, elisa and virus isolation techniques, as well as focma-antibody tests. symptomatology of felv related illnesses is presented. feline lymphoma can be categorized into four anatomic types: thymic, alimentary and multicentric type and true leukemia. forms, which ... | 1984 | 6098972 |
| the management of feline lymphosarcoma. | lymphoma may occur in almost any site, in a cat of any age, in either a felv-infected or uninfected animal. as the most common tumor type found in this species, lsa should be included in the differential diagnosis for virtually any clinical problem in any body system. for the unusual forms of this malignancy, just as for the more common types, the prognosis and response to cytotoxic therapy is generally based on the pretreatment volume and location of the tumor, as well as on the overall status ... | 1984 | 6097009 |
| [detection of antigenic determinants of the major structural proteins of various mammalian type c retroviruses in the leukocytes of patients with hemoblastoses and in healthy donors by the elisa method]. | using the enzyme-labelled antibodies it was shown that extracts from leukocytes of patients with leukemias and healthy donors contain antigenic determinants related to major virus protein of mammalian c type oncornaviruses ssv/ssav, baev, felv and rlv. the highest antigen activity in patients was detected in the feline leukemia (felv) system, and the least one--in the system of murine leukemia (rlv). common antigenic determinants of major virus protein of the viruses under study were detected in ... | 1984 | 6209091 |
| molecular genetic characterization of the rd-114 gene family of endogenous feline retroviral sequences. | rd-114 is a replication-competent, xenotropic retrovirus which is homologous to a family of moderately repetitive dna sequences present at ca. 20 copies in the normal cellular genome of domestic cats. to examine the extent and character of genomic divergence of the rd-114 gene family as well as to assess their positional association within the cat genome, we have prepared a series of molecular clones of endogenous rd-114 dna segments from a genomic library of cat cellular dna. their restriction ... | 1984 | 6090693 |
| lymphosarcoma and persistent feline leukemia virus infection of pet cats: a system to study responses during extracorporeal treatments. | pet cats, persistently infected with feline leukemia virus and having lymphosarcoma, were treated by extracorporeal immunoadsorption using staphylococcus aureus cowan i (which has protein a on its surface) to remove immunoglobulin g and circulating immune complexes. complete viral clearance and long-lasting tumor regression were achieved following such treatments in 9 of 16 cats. in addition, in vitro immunologic assays have been developed that are useful in the clinical evaluation of cats durin ... | 1984 | 6086847 |
| transformation by feline retroviruses. | 1984 | 6099894 | |
| multicentric fibrosarcoma in a cat and a review of the literature. | a case of multicentric fibrosarcoma in a ten month old domestic short-haired cat is presented and discussed. tumor tissue was found to involve the right distal forepaw, right shoulder area and a popliteal lymph node. this anaplastic neoplasm was concentrated primarily in subcutaneous tissues but also extended to muscle, bone and lung. the cat was found to be positive for feline leukemia virus by the elisa test. based on these findings, it is likely that the lesions in this case result from an in ... | 1984 | 17422403 |
| killer cells of feline leukemia virus- and feline sarcoma virus-infected transformed cells: the role of nk, adcc, and in vitro generated cytotoxic cells. | feline white blood cells (wbc) manifested a primary in vitro mixed lymphocyte tumor cell culture (mltc) proliferative response to feline leukemia virus-feline sarcoma virus (felv-fesv)-infected transformed target cells, which reached a peak at day 15. furthermore, primary in vitro mltc cultures generated cytotoxic killer cells capable of killing a variety of targets in non-major histocompatibility gene complex restricted fashion, and effector cells were capable of killing targets introduced repe ... | 1985 | 2992811 |
| feline glucose-6-phosphate dehydrogenase cellular mosaicism. application to the study of retrovirus-induced pure red cell aplasia. | neoplasms result from the uncontrolled proliferation of abnormal or transformed cells. the early stages of this process are difficult to study because of the lack of sensitive and specific markers of clonal evolution in an experimental system. we have developed a cat model using cellular mosaicism for glucose-6-phosphate dehydrogenase (g-6-pd). our findings confirm that the structural locus for feline g-6-pd is on the x-chromosome and demonstrate that it is randomly inactivated in somatic cells. ... | 1985 | 2981248 |
| quantitation of specific antibodies bound to feline leukemia virus in the plasma of pet cats. | a method is described for determining levels of circulating immune complexes (cic) composed of feline leukemia virus (felv) antigens and corresponding antibodies in plasma of persistently-infected pet cats. the procedure is based on the ability of high-titered heterologous anti-felv serum to chase cat anti-felv igg from dissociated cic by successfully competing for binding of free antigen. the eluted cat antibody is then collected and quantitated. in a study of cats in the process of clearing pe ... | 1985 | 2995795 |
| [aids--general characteristics and new clues in the studies of etiopathogenesis of the syndrome--the role of htlv]. | 1985 | 3000090 | |
| feline leukemia virus-and feline sarcoma virus-related polypeptides released by virus producer and nonproducer cells. | polypeptides specific for feline leukemia virus (felv) have been identified in the media of cells that produce felv as well as in nonproducer cells transformed by feline sarcoma viruses (fesv). cat fibroblasts that were persistently infected with felv release the major virus envelope glycoprotein, whereas cultured cat lymphoma cells shed both glycopeptides related to the virus core gene (gag) and glycopeptides related to the virus envelope gene (env). mink cells and cat cells transformed by fesv ... | 1985 | 3002564 |
| isolation from cats of an endogenous type c virus with a novel envelope glycoprotein. | a search for variant endogenous cat viruses led to a novel isolate. although the major envelope glycoprotein of this virus was similar in size to that of an rd-114-like virus that was coisolated, it was unrelated to rd-114 or feline leukemia virus by immunological and biological criteria. this degree of dissimilarity suggests a different evolutionary progenitor from that for the rd-114 and feline leukemia virus viral envelopes. the novel virus did, however, code for gag gene polypeptides which a ... | 1985 | 2983093 |
| antitumor activity of protein a administered intravenously to pet cats with leukemia or lymphosarcoma. | extracorporeal immunoadsorption with protein a (spa) containing staphylococcus aureus cowan i (sac) has previously been shown to induce an antitumor and antiviral response in some feline leukemia virus (felv)-infected, lymphosarcoma (lsa) cats. however, the mechanism by which this response is induced is unknown. since it is possible that spa dissociates from the sac column during treatment, and that intravenous infusion of spa could be a more efficacious form of treatment than extracorporeal imm ... | 1985 | 2983866 |
| animal models: lessons from feline and bovine leukaemia virus infections. | 1985 | 2989623 | |
| retroviruses associated with leukemia and ablative syndromes in animals and in human beings. | t-lymphotropic retroviruses of cats cause lymphopenia and immunosuppression and represent the major cause of death in that species. similarly htlv-i which is t4 tropic is associated with an increased risk for development of infectious disease in regions where the virus is endemic. since htlv-i is also believed to be transmitted by blood and by sexual intercourse we considered the possibility that a variant form of htlv might cause aids. the identification of cross-reactive antibodies to htlv-i-m ... | 1985 | 2990682 |
| ultrastructural morphology of leukemic cells in the cat. | transmission and scanning electron microscopic characteristics of leukemic cells from eight cats with spontaneous leukemia are described. nuclear blebs, myelin figures, cytoplasmic microfibrils and c-type virus were seen more frequently in leukemic cells. surface ridges and ruffles seen with the scanning electron microscopy were helpful in distinguishing myelogenous from lymphogenous leukemia. | 1985 | 2984829 |
| effects of cobra venom factor treatment on latent feline leukemia virus infection. | the role of the complement system in containment of feline leukemia virus infection was studied by cobra venom factor treatment of feline leukemia virus-immune cats. one to three weeks after cobra venom factor treatment, an increase in viral antigen in marrow myelomonocytic cells and circulating immune complexes was noted. prevention of reactivation of feline leukemia virus infection may in part depend on an intact complement system. | 1985 | 2987539 |
| epizootiologic survey of feline leukemia virus in south-kyushu area. | 1985 | 2995717 | |
| molecular analysis of several classes of endogenous feline leukemia virus elements. | five recombinant dna clones of endogenous feline leukemia virus-related dna sequences were isolated by screening a lambda phage genomic library of cat placental dna with a probe specific to the gag-pol region of infectious feline leukemia virus. the clones containing retroviral long terminal repeat-like sequences demonstrated the existence of different size classes of endogenous elements in the cat genome, including those of nearly full length in which the gag region is heterogeneous but all of ... | 1985 | 2415715 |
| characterization of a newly established feline lymphoma-derived cell line (bkd) lacking t and b cell surface markers. | a new feline lymphoma-derived cell line, designated bkd, was isolated from an anterior mediastinal tumor. cells of this line were characterized as lymphoid based on morphology, the lack of intracellular esterase and peroxidase activity, and absence of phagocytic function. in contrast with other established feline lymphoma-derived cell lines, cells of the bkd line lack characteristics of both feline t-cells and b-cells in that they neither form rosettes with guinea pig erythrocytes nor have demon ... | 1986 | 2423498 |
| transmission of feline leukaemia virus in the milk of a non-viraemic cat. | the possibility of the transmission of feline leukaemia virus (felv) from latently infected cats was studied. five female cats with latent infections were examined for evidence of transmission of the virus to their kittens. one of the cats infected members of four consecutive litters of kittens which subsequently became persistently viraemic and transmitted the virus to other susceptible kittens by contact. shortly after birth its kittens were apparently felv-free since neither viral antigen nor ... | 1986 | 3012849 |
| histopathological and hematological findings in myeloid leukemia induced by a new feline leukemia virus isolate. | myeloid leukemia was induced by a new feline leukemia virus isolate felv-ab/gm-1 in a high proportion of cats. the latency period was short. three to 5 weeks after infection early changes were detectable in the bone marrow, and cats developed leukemia 5 to 8 weeks after infection. the results of the present histological and cytological studies suggested that there were two stages in the development of leukemia. the first stage appeared to be equivalent to the syndrome of bone marrow dysplasia or ... | 1986 | 3018983 |
| a feline retrovirus induced t-lymphoblastoid cell-line that produces an atypical alpha type of interferon. | a cell-line, designated lsa-1, was derived from a thymic lymphosarcoma that occurred in a cat with experimentally induced feline leukemia virus (felv) infection. lsa-1 cells possessed surface receptors and antigens of normal t-lymphocytes, but were unresponsive to interleukin-2 stimulation. the lsa cell-line was found to constitutively produce and release an interferon into the culture supernatants. production of this interferon was enhanced in certain clones of the original lsa-1 cell lines. th ... | 1986 | 3006326 |
| multilineage, non-species specific hematopoietic growth factor(s) elaborated by a feline fibroblast cell line: enhancement by virus infection. | in studies designed to determine the role of feline leukemia virus (felv) in the pathogenesis of marrow failure in the cat, we tested medium conditioned by uninfected and felv-infected feline embryonic fibroblasts (fea) for its effect on hematopoietic colony growth in culture. as opposed to an inhibitory effect, we found that the conditioned medium (cm) from fea or fea/felv increased the in vitro growth of multiple hematopoietic progenitor cell types including erythroid burst-forming cells (bfu- ... | 1986 | 3007539 |
| comments on evaluation of diagnostic test results. | 1986 | 3015848 | |
| [enzootic bovine leukosis and feline leukosis. 2 current animal models for the study of virus-induced lymphomas and immunodepression syndrome in man]. | 1986 | 3030513 | |
| a new acute transforming feline retrovirus with fms homology specifies a c-terminally truncated version of the c-fms protein that is different from sm-feline sarcoma virus v-fms protein. | the hz5-feline sarcoma virus (fesv) is a new acute transforming feline retrovirus which was isolated from a multicentric fibrosarcoma of a domestic cat. the hz5-fesv transforms fibroblasts in vitro and is replication defective. a biologically active integrated hz5-fesv provirus was molecularly cloned from cellular dna of hz5-fesv-infected fre-3a rat cells. the hz5-fesv has oncogene homology with the fms sequences of the sm-fesv. the genome organization of the 8.6-kilobase hz5-fesv provirus is 5' ... | 1986 | 3018286 |
| [feline leukemia: current status regarding prevention]. | particularly as a result of the increasing popularity of keeping cats as pets, feline leukaemia constituted a risk to the cat population for many years; it was uncontrollable because of its insidious course and the spread of the virus, which passed unnoticed. during the past decade, diagnostic laboratory tests resulted in progress in the control of the infection for the first time. dissemination of the virus could then at least be checked to some extent. prevention by vaccination did not appear ... | 1986 | 3006279 |
| humoral immune response of asymptomatic cats naturally infected with feline leukemia virus. | the humoral immune response of cats that were naturally infected with the feline leukemia virus (felv) was examined after antigenic stimulation with the synthetic antigen poly(l-tyr, l-glu)-poly(dl-ala)-poly(l-lys). the primary humoral antibody response in felv-infected cats was both delayed and greatly reduced, compared with that seen in uninfected control cats. a similar discordance was observed after secondary stimulation with the antigen, in the felv-infected cats had both a delayed response ... | 1986 | 3022000 |
| control of feline leukaemia virus infection by a removal programme. | 1986 | 3026079 | |
| guinea pig erythrocyte rosette formation as a nonspecific cell surface receptor assay in the cat. | the specificity of guinea pig erythrocyte (gpe) rosettes for feline peripheral blood lymphocytes was studied. of the gpe rosette-positive cells from peripheral blood, 54% were monocytes, 29% were granulocytes, and only 17% were lymphocytes. results were similar for rosettes incubated at 4 c and those incubated at 37 c. mononuclear cells separated with polyvinylpyrrolidone-coated silica formed fewer monocyte rosettes (49%) and more granulocyte rosettes (34%) than did cells separated with sodium d ... | 1986 | 3954230 |
| 3'-azido-3'-deoxythymidine in feline leukemia virus-infected cats: a model for therapy and prophylaxis of aids. | due to similarities between human immunodeficiency virus and feline leukemia virus, the etiological agents of acquired immunodeficiency syndromes in humans and cats, the feline system was used as a model to conduct preliminary investigations as to the efficacy of the thymidine analogue 3'-azido-3'-deoxythymidine (azt) as a therapeutic and preventive agent against retroviruses. in vitro evaluations of azt cytotoxicity and its antiviral effects were conducted. subsequently, 50 6-week-old specific ... | 1987 | 3034403 |
| prevalence of feline leukemia virus infection in random source laboratory cats. | three years of quarantine data involving the prevalence of feline leukemia virus (felv) in laboratory cats (felis catus) was evaluated. testing was performed using a commercially available elisa system. annual prevalence of infection ranged from 5.4 to 10.7% of the 937 cats tested. results obtained with the enzyme linked immunosorbent assay (elisa) system compared well with tests performed using an immunofluorescent antibody assay system (ifa). seasonal periodicity was noted with higher infectio ... | 1987 | 3039250 |
| [feline leukemia virus (felv) and felv-associated diseases in cats: a review]. | feline leukaemia virus (felv) usually occurs in its natural species, the domestic cat. felv is also important to human individuals as a comparative model, as felv may cause a variety of diseases which are partly malignant and partly benign, such as immunosuppression which bears a resemblance to aids (acquired immune deficiency syndrome) in man. although felv is a common infective agent, the incidence of disease due to felv is much higher in cats kept in closed households in which several of them ... | 1987 | 3039686 |
| transforming potential of a myc-containing variant of feline leukemia virus in vitro in early-passage feline cells. | we studied a naturally occurring variant of feline leukemia virus (felv) in which the oncogene myc has substituted for a portion of the viral structural genes (myc-felv). myc-felv was rescued by replication in the presence of felv as helper, and its biological activity was examined in early-passage feline cells in vitro. infection of leukocytes from peripheral blood, spleen, or thymus, or of kitten fibroblasts did not immortalize these cells or alter them morphologically. northern blot (rna blot ... | 1987 | 3041029 |
| suppression of in vitro neutrophil function by feline leukaemia virus (felv) and purified felv-p15e. | feline neutrophils (pmn) were isolated and exposed to ultraviolet light-inactivated feline leukaemia virus (uv-felv) and purified envelope component p15e (felv-p15e). functional capacity of exposed pmn was measured in vitro utilizing the chemiluminescence (cl) response. pmn exposed to uv-felv demonstrated depressed cl responses to ca2+-ionophore a23187 and latex particles. however, felv-p15e produced significant suppression in the cl response to a23187 but failed to produce significant alteratio ... | 1987 | 3029288 |
| retroviral transduction of t-cell antigen receptor beta-chain and myc genes. | support for multistage models of oncogenesis has been provided by several highly leukaemogenic retrovirus isolates that have transduced more than one host cell gene. where functional studies have been performed, these retroviral oncogenes show synergy for in vitro transformation and leukaemogenesis. in naturally occurring feline leukaemias associated with feline leukaemia virus (felv), retroviral transduction of myc is a frequent oncogenic mechanism. but evidence suggesting that the felv v-myc g ... | 1987 | 3029597 |
| lymphocytes and antibody in retrovirus-induced feline pure red cell aplasia. | the possible role of antibody and t-lymphocytes was investigated in the pure red cell aplasia (prca) associated with feline leukemia virus, subgroup c (felv-c), infection. in previous studies, erythroid colony-forming cells were undetectable in marrow culture of cats with prca. yet erythroid burst-forming cells (bfu-e) remained, suggesting that bfu-e were able to differentiate in vitro but not in vivo. it was inferred that immunologic suppression may contribute to the pathogenesis of feline prca ... | 1987 | 3025500 |
| suppressive effect on polyclonal b-cell activation of a synthetic peptide homologous to a transmembrane component of oncogenic retroviruses. | purified feline leukemia virus, uv light-inactivated feline leukemia virus, and a synthetic peptide (cks-17) homologous to a well-conserved region of the transmembrane components of several human and animal retroviruses were each studied for their effects on igg production by feline peripheral blood lymphocytes. using a reverse hemolytic plaque assay, both the viable virus and the uv-inactivated feline leukemia virus, but not the cks-17, activated b lymphocytes to secrete igg. when staphylococca ... | 1987 | 3025858 |
| selective removal of antigen-complexed igg from cat plasma by adsorption onto a protein a-silica matrix. | the binding of normal cat igg, heat-aggregated cat igg and specific immune complexes (ic) containing cat igg to a silica matrix containing covalently bound staphylococcus aureus protein a was evaluated. the amounts of serum relative to protein a-silica, the flow rates and the perfusion times were representative of those existing when protein a-silica columns are used for therapeutic extracorporeal immunoadsorption of igg and ic from humans and animals. when cat igg was present in a large excess, ... | 1987 | 3039006 |
| effects of treatment with cobra venom factor on experimentally induced feline leukemia. | five- to six-month-old specific-pathogen-free cats were exposed to cobra venom factor (cvf) alone (4 cats), rickard feline leukemia virus (felv; 9 cats), or cvf and felv (6 cats). host-virus relationships were evaluated by monitoring the development of viremia, production of antibody against feline oncornavirus-associated cell membrane antigen, and amount of circulating immune complexes (cic). exposure to cvf induced complement depletion, which lasted 8 to 15 days. however, complement depletion ... | 1987 | 2820273 |
| structural abnormality and over-expression of the myc gene in feline leukemias. | tumor cells of feline leukemia were examined for structural abnormality and expression of the myc gene. four of 12 spontaneous leukemia cases showed structural abnormalities of the myc gene detected by southern blotting analysis. of these 4 cases, one (case 1) showed a dna rearrangement in the 5' portion of the c-myc locus associated with integration of feline leukemia virus (felv) genome. another case had a newly inserted myc gene which was transduced by felv. in the 2 other cases, no relation ... | 1987 | 2822586 |
| experimental transmission and pathogenesis of immunodeficiency syndrome in cats. | we describe the identification, experimental transmission, and pathogenesis of a naturally occurring powerfully immunosuppressive isolate of feline leukemia virus (designated here as felv-faids) which induces fatal acquired immunodeficiency syndrome (aids) in 100% (25 of 25) of persistently viremic experimentally infected specific pathogen-free (spf) cats after predictable survival periods ranging from less than 3 months (acute immunodeficiency syndrome) to greater than one year (chronic immunod ... | 1987 | 2823940 |
| feline leukemia virus: current status of the feline induced immune depression and immunoprevention. | this is a review of the current knowledge of feline leukemia virus (felv) associated with immune depression observed in cats. it will focus on the clinical and experimental observations associated with feline retroviral infection and presence in vivo and in vitro. we will briefly describe retroviral-associated acquired immune deficiency syndrome associated with felv infection in the cat and specific cellular pathology associated with felv latency. in addition, we will focus on the action of felv ... | 1987 | 2826030 |
| murine monoclonal antibodies cross-reactive with feline peripheral blood mononuclear cells. | twelve murine monoclonal antibodies (mab), specific for canine, human, and mouse cell surface determinants on lymphohemopoietic cells, were tested for reactivity (using indirect immunofluorescence) with peripheral blood mononuclear cells (pbmc) from 3 normal cats and 3 felv-positive cats with lymphoblastic leukemia. mab dly6 and 1h3, specific for canine lymphocytes, mab hb57s, specific for human mu(igm) chain, mab j-118 40.164.3 and h81.98.71, specific for murine and human ia, all had higher bin ... | 1987 | 2829413 |
| isolation of a t-lymphotropic virus from domestic cats with an immunodeficiency-like syndrome. | a highly t-lymphotropic virus was isolated from cats in a cattery in which all the animals were seronegative for feline leukemia virus. a number of cats in one pen had died and several had an immunodeficiency-like syndrome. only 1 of 18 normal cats in the cattery showed serologic evidence of infection with this new virus, whereas 10 of 25 cats with signs of ill health were seropositive for the virus. tentatively designated feline t-lymphotropic lentivirus, this new feline retrovirus appears to b ... | 1987 | 3643650 |
| feline haemobartonellosis: clinical, haematological and pathological studies in natural infections and the relationship to infection with feline leukaemia virus. | haemobartonella felis infection was demonstrated in 38 cats which could be divided into four groups as follows: group a, feline leukaemia virus (felv) free cats with h felis infection alone; group b, felv free cats with h felis infection and other clinical conditions; group c, felv positive cats with h felis infection but no clinical manifestation of felv related or any other intercurrent disease; and group d, felv positive cats with h felis infection and clinical manifestations of felv related ... | 1988 | 2834861 |
| effect of diethylcarbamazine on serum antibody to feline oncornavirus-associated cell membrane antigen in feline leukemia virus cats. | diethylcarbamazine (n,n-diethyl-4-methyl-1-piperazine carboxamide; dec) is a drug frequently used for prevention and treatment of the filariases. an opsonic action of dec may generate increased immune responses to microfilariae. we tested the hypothesis that dec treatment could result in higher antibody levels to other infectious agents. a retroviral animal model was studied, in light of the consideration that use of dec as an antifilarial agent could conceivably alter seroepidemiologic surveys ... | 1988 | 2836593 |
| use of a subunit feline leukemia virus vaccine in exotic cats. | three adult bengal tigers, 2 immature white tigers, and 3 adult servals were vaccinated im with three 1-ml doses of a subunit felv vaccine with dosage interval guidelines of the manufacturer. all cats had increased antibody titers to felv gp 70 capsular antigen and feline oncornavirus cell membrane-associated antigen during the vaccination trial. three weeks after the third vaccination, 7 of the 8 cats had gp70 antibody titers greater than 0.2 (optical density), and all 8 cats had feline oncorna ... | 1988 | 2835347 |
| structure and function of endogenous feline leukemia virus long terminal repeats and adjoining regions. | the nucleotide sequence of the 5' long terminal repeat (ltr) of three independent loci (cfe-6, cfe-16, and cf-14) of endogenous feline leukemia virus (felv) dnas of the domestic cat genome was determined. the 3' ltr of the cfe-6 clone was also sequenced. the endogenous felv ltrs, which were very similar to each other in sequence and in organization of the functional domains, differed considerably from the exogenous felv ltr in the u3 region. the major differences in u3 included variations in set ... | 1988 | 2843665 |
| fluorometric enzyme immunoassay for measurement of infectious feline leukemia virus and its neutralization. | a fluorometric enzyme immunoassay using an alkaline phosphatase-conjugated monoclonal antibody was developed to quantitate feline leukemia virus (felv) infection. monoclonal antibodies, directed against the felv structural protein p27, were conjugated with alkaline phosphatase using a modified maleimide method. the enzyme immunoassay requires only 4 days to reproducibly measure felv production instead of the 12 days required for the commonly used transformation assay using c81 cells. a linear co ... | 1988 | 2846700 |
| feline immunodeficiency syndrome--a comparison between feline t-lymphotropic lentivirus and feline leukemia virus. | a feline t-lymphotrophic lentvirus (ftlv) has recently been isolated from a domestic cat free of feline leukemia virus (felv). this virus is distinct from felv (an oncornavirus), although they share a common denominator, namely, the ability to cause immunosuppression and induce lymphadenopathy and anemia. their differences can be revealed by examining the following: the metal requirement for reverse transcriptase activity, the antigenic comparison by western blot analysis, the different suscepti ... | 1988 | 2848998 |
| igg-fc-receptor positive and negative t cells from feline leukemia virus-infected cats. | 1988 | 2850387 | |
| transduction of endogenous envelope genes by feline leukaemia virus in vitro. | feline leukaemia viruses (felv) are exogenous retroviruses that can be detected in most cats with leukaemia, aplastic anaemia, myeloproliferative diseases and fatal immunosuppression. felv isolates have been divided into three subgroups, based on the viral envelope-determined properties of interference and host range in vitro. felv-a is present in all natural isolates and is generally minimally pathogenic. felv-b is found with felv-a in isolates from approximately 40% of natural infections and i ... | 1988 | 2895894 |
| retroviruses: leukemia and immunosuppression. the yohei ito memorial lecture. | 1988 | 2904514 | |
| tumorigenic potential of a myc-containing strain of feline leukemia virus in vivo in domestic cats. | the oncogenic capacity of a myc-containing strain of feline leukemia virus (felv), termed lc-felv, has been examined after inoculation of the virus into neonatal kittens. like other myc-containing strains of felv, lc-felv may induce with relatively short latency, but does not necessarily induce, thymic lymphosarcoma in viremic animals. naturally occurring and experimentally induced tumors are t-cell lymphomas which contain clonally integrated lc-felv proviral dna and which cannot readily be cult ... | 1988 | 2846887 |
| chronic idiopathic neutropenia in a cat. | persistent neutropenia (0-0.6 x 10(9) neutrophils/l) was documented during a 10-month period in a 4-year-old spayed female domestic shorthair cat that was presented for anorexia and depression. salient abnormalities detected on physical examination were fever (40.3 degrees c), dehydration, and gingivitis. the cat was neutropenic (0.5 x 10(9) neutrophils/l) and enzyme-linked immunosorbent assay (elisa) test for feline leukemia virus was negative. a bone marrow aspirate showed decreased numbers of ... | 1988 | 3221355 |
| feline lymphomas: immunological and cytochemical characterization. | the immunological and cytochemical phenotypes of five primary feline lymphomas and six feline lymphoma lines are reported. thymic lymphomas induced by the rickard strain of felv (felv-r) are of prothymocyte or (immature) cortical thymocyte origin, as these express terminal deoxynucleotidyl transferase, the guinea pig erythrocyte rosette receptor, ia antigens, partial cortisone sensitivity, and nonspecific esterase. lymphomas associated with other strains of felv form rosettes with guinea pig ery ... | 1989 | 2535958 |
| feline leukemia virus and feline immunodeficiency virus infections in a cat with lymphoma. | lymphoma was diagnosed in a 7-year-old domestic cat found to be infected with felv and feline immunodeficiency virus (fiv). the cat was affected by chronic disorders suggestive of immunosuppression, including gingivitis, periodontitis, keratitis, and abscesses. despite treatment, peripheral keratitis of the left eye progressed, resulting in uveitis, chronic glaucoma, and eventual corneal rupture. microscopic retinal and optic disk pathologic processes also were suspected. abnormal jaw movements ... | 1989 | 2537274 |
| feline leukemia virus-induced immunodeficiency syndrome in cats as a model for evaluation of antiretroviral therapy. | severe progressive immunodeficiency syndrome can be induced experimentally with a molecularly cloned isolate of feline leukemia virus (felv-faids). the resultant disease syndrome is characterized by persistent viremia, lymphopenia, progressive weight loss, persistent diarrhea, enteropathy, and opportunistic infections. the onset of clinical immunodeficiency disease is prefigured by the replication of the felv-faids variant virus in bone marrow and other tissues. the felv-faids system can be used ... | 1989 | 2540109 |
| retroviruses and malignant lymphoma. | retroviruses are single stranded rna viruses that possess a unique enzyme, reverse transcriptase. this enzyme facilitates the synthesis of double stranded dna intermediates able to integrate into the genome of the host cell. although primarily a means of remaining latent, this integration can have the effect of transforming the cell to malignant growth, either by activation of growth control genes in cis or trans, or by insertion of an integrated oncogene. malignant lymphomas caused by retroviru ... | 1989 | 2541838 |
| treatment of felv-induced immunodeficiency syndrome (felv-faids) with controlled release capsular implantation of 2',3'-dideoxycytidine. | 2',3'-dideoxycytidine (ddc) inhibits replication of the immunodeficiency inducing strain of feline leukemia virus (felv-faids) in vitro at concentrations ranging from 1-10 micrograms/ml. additive antiviral effect is achieved when ddc is combined with either human recombinant alpha interferon (ifn alpha) or tumor necrosis factor (tnf) plus ifn alpha. initial in vivo pharmacokinetic studies in cats, utilizing bolus intravenous administration of ddc (20 mg/kg), resulted in peak plasma concentration ... | 1989 | 2544137 |
| feline cytotoxic large granular lymphocytes induced by recombinant human il-2. | large granular lymphocytes (lgl) have been characterized phenotypically and functionally as cytotoxic t lymphocytes, nk cells or lymphokine-activated killer cells. the most prominent morphologic feature of lgl is large cytoplasmic granules that are thought to contain the molecules responsible for cell lysis. in this study, we describe the morphologic and functional characteristics of il-2-dependent cytotoxic lymphocytes derived from feline pbl. stimulation of feline pbl with con a followed by cu ... | 1989 | 2544649 |
| diagnosis of feline leukemia virus and feline immunodeficiency virus infections. | feline leukemia virus is an oncogenic retrovirus that can result in a wide variety of neoplastic and non-neoplastic diseases, including immunosuppression. diagnosis of felv infection can be achieved by several methods, including virus isolation; ifa assay of a peripheral blood smear; and detection of a viral protein (called p27) by elisa testing of whole blood, plasma, serum, saliva, or tears. commercially available elisa kits have revolutionized felv testing and have become very popular as "in- ... | 1989 | 2549672 |
| nucleotide sequence and distinctive characteristics of the env gene of endogenous feline leukemia provirus. | nucleotide sequence analysis of the env gene of two different endogenous feline leukemia virus (felv) loci, cfe-6 and cfe-16, of domestic cats revealed the following characteristics. (i) both proviruses contain an open reading frame in the env region; (ii) whereas the full complement of the exogenous felv env is generally present in cfe-6 dna, it is truncated in cfe-16 dna such that the 5' half of the gp70 domain and the untranslated region 3' to the p15e domain have been fused by an internal de ... | 1989 | 2539525 |
| control of feline leukaemia virus. | feline leukaemia virus (felv) usually occurs in its natural species, the domestic cat. felv is also important to human individuals as a comparative model, as it may cause a variety of diseases, some malignant and some benign, such as immunosuppression, which bears a resemblance to aids (acquired immune deficiency syndrome) in man. felv is transmitted among cats by contagion. the main sources of infection are persistently infected carrier cats which continuously excrete virus. dissemination of fe ... | 1989 | 2549695 |
| [cat retroviruses and human retroviruses: elements of comparison]. | following emotional head-lines of certain articles in the press, making believe that the cat could be susceptible to the aids virus, the authors present elements of comparison between principal feline retroviruses (the feline leucosis virus and the feline immunodeficiency virus) and the two human immunodeficiency viruses (hiv). the feline leucosis virus in differentiated from the human and the feline immunodeficiency viruses by its virological, pathological and epidemiological characteristics. b ... | 1989 | 2553219 |
| on interpretation of feline leukemia test results. | 1989 | 2557312 | |
| immunodeficiency in latent feline leukemia virus infections. | challenge of naive experimental animals with a retroviral inoculum may result in one of two broad sequelae. the first is the establishment of an appropriate humoral and cellular immune response leading to a condition of immunity to subsequent infection with the retrovirus. alternatively, the host may fail to develop a successful immune response, resulting in a chronic viremia associated with immunosuppression and ultimately death due to secondary pathogens. an alternate disease course is the est ... | 1989 | 2549692 |
| induction of aplastic anemia by intra-bone marrow inoculation of a molecularly cloned feline retrovirus. | intra-bone marrow inoculation of cells infected with molecularly cloned feline retrovirus (felv-c-sarma [fsc]) associated with aplastic anemia was examined to test the hypothesis that cell-to-cell transmission of virus might facilitate marrow cell infection and anemogenesis, a possibility suggested by in-vitro co-culture experiments. ibm inoculation of either fsc-infected feline marrow cells or fibroblasts of weanling cats bypassed age-related restriction of fsc replication, initiated viremia, c ... | 1989 | 2552228 |
| animal models of aids. | animal models of aids are essential for understanding the pathogenesis of retrovirus-induced immune deficiency and encephalopathy and for development and testing of new therapies and vaccines. aids and related disorders are etiologically linked to members of the lentivirus subfamily of retroviruses; these lymphocytopathic lentiviruses are designated human immuno-deficiency virus type 1 (hiv-1) and human immuno-deficiency virus type 2 (hiv-2). the only animals susceptible to experimental hiv-1 in ... | 1989 | 2556312 |
| feline immunodeficiency virus and feline leukemia virus infections and their relationships to lymphoid malignancies in cats: a retrospective study (1968-1988). | sera from 353 cats with naturally occurring feline leukemia virus (felv) infection were collected in boston, los angeles, new york city, and seattle between 1968 and 1988. these sera were retrospectively assayed by enzyme-linked immunosorbent assay for antibodies to feline immunodeficiency virus (fiv). fifty-one (14.4%) of the felv-positive sera had antibodies to fiv, indicating dual oncovirus and lentivirus infections. fiv infections were confirmed by western blot analysis, antibodies against t ... | 1990 | 2159993 |
| evaluation of humoral immunity tests in felv infected cats. | 1990 | 2178116 | |
| inhibition of phorbol ester-induced neutrophil chemiluminescence by felv. | receptor-mediated activation is accompanied by phospholipid metabolism and by calcium fluctuation resulting in a chemiluminescence (cl) response in the neutrophil. this pathway involves activation of protein kinase c (pkc) and the nadph oxidase. artificial stimulants such as phorbol esters, specifically 12-o-tetradecanylphorbol-13-acetate (tpa), circumvent the receptor-mediated pathway and activate pkc resulting in a measurable cl response. neutrophils from feline leukemia virus (felv) exposed c ... | 1990 | 2158290 |
| a feline large granular lymphoma and its derived cell line. | a lymphoma cell line (mcc) was derived from an abdominal mass from a 13-yr-old castrated male cat. the cells resemble natural killer precursor cells, have membrane-bound granules, and are positive for chloroacetate esterase, alpha-naphthyl butyrate esterase, and tartrate-resistant acid phosphatase activities. the mcc cells are negative for rearranged feline t-cell receptor genes, negative for feline t-cytotoxic antigen, ia, and surface mu, tau, and lambda chains and do not form e-rosettes. the m ... | 1990 | 2161827 |
| existence of feline immunodeficiency virus infection in japanese cat population since 1968. | 1990 | 2168001 | |
| therapy of presymptomatic felv-induced immunodeficiency syndrome with azt in combination with alpha interferon. | azt inhibited replication of an immunodeficiency-inducing strain of feline leukemia virus (felv-faids) in vitro at concentrations as low as 0.005 microgram/ml. this antiviral activity was augmented an additional 25-30% when azt was combined with human recombinant alpha-interferon (2b) (ifn alpha). administration of azt alone or in combination with ifn alpha, beginning at the time of exposure to a 100% persistent viremia-inducing dose of felv-faids, abrogated the progression of viral infection an ... | 1990 | 1964030 |
| effect of administration of diethylcarbamazine on murine leukemia virus (cas-br-m) infected mice. | previous studies indicate that decreased serum viral infectivity and viral antigen levels follow oral administration of diethylcarbamazine (dec) in feline leukemia virus infected cats, even though dec has not been shown to exhibit in vitro antiviral activity. in this investigation, dec was given by oral administration or (single dose) ip injection to murine leukemia virus (cas-br-m) inoculated mice to permit evaluation of its effect on viral-induced central nervous system disease. the survival o ... | 1990 | 1967004 |
| lymphocyte population changes in cats naturally infected with feline immunodeficiency virus. | feline immunodeficiency virus (fiv) is associated with feline acquired immunodeficiency syndrome (faids) and has been suggested as a model for hiv-induced human aids. the most obvious immunological defect in hiv infection is a reduction in cd4+ cell numbers and an inversion of the cd4:cd8 ratio. to determine whether the same is true in fiv infection, we analyzed by flow cytometry using a panel of monoclonal antibodies to feline lymphocyte populations the cd4:cd8 ratios in cats naturally infected ... | 1990 | 1982410 |
| should cats be vaccinated for feline leukemia? | 1990 | 2163809 | |
| [feline immunodeficiency virus in switzerland: clinical aspects and epidemiology in comparison with feline leukemia virus and coronaviruses]. | serum samples from 1421 domestic cats (561 healthy, 860 sick) were tested for fiv-, felv- and coronavirus infection. the results were stored in a computer data base and compared with epidemiologic data and clinical findings. all 3 infections were significantly more prevalent in sick than healthy cats: fiv was found in 0.7% of healthy and 3.4% of sick cats. for felv the prevalence was 3.0% and 13.0% and for coronavirus 21% and 36.2%, respectively. fiv-infected cats were mostly male (73%); no sex ... | 1990 | 2167513 |