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Biomedical subjects

C C Muscoplat

Publications and source records attributed to C C Muscoplat.

At least 73 records · Page 4Linked to original sources
PubMed1978

Microculture method for mixed lymphocyte cultures in the horse.

A miniaturized method for the mixed lymphocyte culture test in the horse is described. The test is performed in either round- or flat-bottom microtitration tissue culture plates. Concentrations of responsing and stimulating cells are varied, depening on the experiment. Significant discrimination between isogeneic and allogenic mixtures is possible after 120 hours' culture when cells are labeled ([3H]thymidine) for the last 16 to 18 hours of the test.

Animals↗
PubMed1978

Maternal immunity to infectious bovine rhinotracheitis and bovine viral diarrhea viruses: duration and effect on vaccination in young calves.

The immune response to modified live-virus bovine viral diarrhea (BVD) vaccine and infectious bovine rhinotracheitis (IBR) vaccine was examined in calves that had received passive maternal antibodies to these viruses. Blood serum samples from vaccinated and control (nonvaccinated) calves were examined for more than 1 year to determine the rate of decline of passive anti-BVD and anti-IBR antibodies and the effect that vaccination had on these antibody titers. The control calves lost their antibodies to BVD and IBR viruses at the rate of one half their remaining antibody titer every 21 days. Calves serologically responded to BVD vaccine at a time when maternal antibody titers remained between 1:96 and 1:20. However, animals did not seroconvert to the IBR vaccine until maternal antibodies had decreased and become undetectable. Evidence is presented to show that although passive immunity will inhibit IBR vaccination, priming for a secondary response will occur so that on subsequent vaccination, at a time when maternal antibodies have disappeared, the animals will respond anamnestically to IBR vaccination.

Animals↗
PubMed1978

Frequency of lymphocytes bearing Fc receptors and surface membrane immunoglobulins in normal, persistent lymphocytotic and leukemia cows.

Fluoresceinated, heat-aggregated bovine immunoglobulins (B-IgG) and human immunoglobulins (H-IgG) were used to detect a receptor for the crystallizable fragment (Fc) of the immunoglobulin molecule on peripheral blood lymphocytes (PBL) of cattle. The aggregated and B-IgG and H-IgG bound to the bovine PBL, but aggregated H-IgG was found to be more sensitive for the detection of Fc receptors. The specificity of aggregated H-IgG binding to the Fc receptors was established by demonstrating that antigen-antibody complexes inhibited this binding, and unaggregated H-IgG did not bind significantly to PBL. Double-labeling experiments suggested that all Fc+ cells have surface immunoglobulins (SIg), a marker for B lymphocytes. The percentage of Fc+ and SIg+ cells in normal animals was 9.5% (range 4-15%) and 16.2% (range 4.5-30.2%), respectively. Persistent lymphocytotic cows had 2.71 times more Fc+ and 3.85 times more SIg+ lymphocytes than did normal cows. Cows with lymphosarcoma had a lower percentage of Fc+ and SIg+ cells than did cows with persistent lymphocytosis. Cases with thymic lymphosarcoma and those with the skin form of leukemia had normal percentages of Fc+ and SIg+ cells.

Animals↗
PubMed1978

Ontogeny of circulating B lymphocytes in neonatal calves.

The ontogeny of lymphocytes bearing surface immunoglobulin (B lymphocytes) in the peripheral blood of neonatal and young calves was determined by fluorescent antibody techniques in calves from one day to 140 days old. The percentage of B lymphocytes in neonatal calves (less than one week) was approximately 5% of the total mononuclear cell population. B lymphocytes increased steadily in the peripheral blood of calves until 20 weeks of age when values stabilised (approximately 19%) and were similar to adult levels.

Animals↗
PubMed1978

Kinetics of in vitro bovine lymphocyte immunostimulation with a Brucella abortus antigen.

A Brucella abortus-soluble antigen was investigated, using in vitro assay of lymphocyte immunostimulation, to determine which concentration of this antigen and which period of incubation of the lymphocyte cultures would induce maximum specific lymphocyte immunostimulation as an additional method for further study of B abortus infection in cattle. Soluble antigen was prepared from autoclaved cells of B abortus strain 1119-3. Peripheral blood lymphocytes were obtained from cattle infected with B abortus and from healthy control cattle not infected with B abortus. The lymphocytes were prepared by the Ficoll-Hypaque density gradient technique, suspended in RPMI 1640 medium (1.5 X 10(6)/ml), cultured with several dilutions of soluble antigen, and incubated. Prior to termination of incubation, cultures were labeled with 1 muCi of [3H]thymidine and, after harvesting, assayed for [3H]thymidine incorporation in DNA by a liquid scintillation spectrometer. Maximum specific immunostimulation of lymphocytes from B abortus-infected cattle was induced in this assay system with 6 days' incubation and 22 microgram of protein/ml/1.5 X 10(6) lymphocytes, using protein content to express concentration of soluble antigen in this system.

Animals↗
PubMed1978

Specific lymphocyte stimulation in cattle naturally infected with strains of Brucella abortus and cattle vaccinated with Brucella abortus strain 19.

Cell-mediated immune responses in cattle naturally infected with strains of Brucella abortus and in cattle vaccinated with B abortus strain 19 during calfhood were studied by an in vitro lymphocyte-stimulation procedure. Lymphocytes were prepared from peripheral bovine blood by the Ficoll-diatrizoate technique, suspended in RPMI-1640 medium (1.5 X 10(6) lymphocytes/ml), cultured with B abortus-soluble antigen or phytohemagglutinin, and incubated for 6 days. Sixteen hours prior to termination of incubation, cultures were labeled with 1 muCi of [3H]thymidine (3HdT) and, after harvesting, assayed for 3HdT incorporation into DNA by liquid scintillation spectrometry. Lymphocytes from cattle with bacteriologically confirmed isolation of B abortus underwent a significantly higher lymphocyte stimulation with B abortus-soluble antigen than did cattle vaccinated with B abortus strain 19 during calfhood (P less than 0.005). Standard seroagglutination tests were conducted simultaneously with lymphocyte-stimulation tests, but there was no apparent correlation between levels of humoral antibodies and the cell-mediated immune responses as measured by in vitro specific lymphocyte stimulation.

Agglutination Tests↗
PubMed1978

In vitro stimulation of bovine peripheral blood lymphocytes: effect of short-term storage of blood prior to lymphocyte culture.

Storage of peripheral blood from Mycobacterium bovis-sensitized cattle from 1 to 48 hours at 4, 22, and 37 C was shown not to alter markedly the lymphocyte blastogenic response to M bovis-purified protein derivative. Concanavalin A-induced lymphocyte mitogenic responses were unaffected by storage of blood for 1, 24, or 48 hours at 22 C and 37 C; however, storage of blood for 48 hours at 4 C significantly lowered (P less than 0.05) mitogenic responses to concanavalin A, as compared with responses to blood kept at 22 C. Mononuclear cell recovery from stored blood at all temperatures was markedly less than that from freshly drawn blood samples. Cell recoveries were most affected by storage of blood at 4 C and 37 C.

Animals↗
PubMed1978

In vitro stimulation of bovine peripheral blood lymphocytes: analysis of variation of lymphocyte blastogenic response in normal dairy cattle.

Lymphocyte immunostimulation tests were performed on 12 lactating dairy cows once every 2 weeks for 1 year. The results indicated that the greatest response of peripheral blood lymphocytes to mitogens occurred in 4- to 6-year-old cows in the month of August and in cows at 2 months before the end of the gestation and again at 1 month after parturition. The least lymphocyte mitogenic response was shown in 7- to 9-year-old cows in the month of February or at parturition and 2 to 4 months after parturition. The magnitude of variations in lymphocyte blastogenic response is reported.

Age Factors↗
PubMed1978

Cell-mediated immune responses in swine from a herd infected with Brucella suis.

Cell-mediated immune (CMI) responses in swine naturally infected with Brucella suis biotype 3, swine suckling an infected sow and Brucella-noninfected swine were studied by an in vitro lymphocyte transformation procedure. The antigen used was a soluble antigen prepared from killed cells of B suis biotype 3. Lymphocytes were prepared from peripheral swine blood by the Ficoll-Hypaque technique, suspended in RPMI-1640 medium (1.5 X 10(6) lymphocytes/ml), cultured with B suis-soluble antigen or concanconcanavalin A, and incubated for 6 days. Sixteen hours prior to termination of incubation, cultures were labeled with 1 muCi of [3H]thymidine and, after harvesting, were assayed for [3H]thymidine incorporation into DNA by liquid scintillation spectrometry. Agglutination tests were conducted on sera collected simultaneously with samples for lymphocyte-stimulation tests. The B suis-soluble antigen elicited specific stimulation in lymphocytes from infected pigs. On a group basis, there was high correlation between the amount of serum antibodies and specific lymphocyte stimulation, but on an individual animal basis, there was little correlation of the results of both systems in infected swine. There was high correlation between recovery of Brucella from the tissues of animals and the degree of CMI response. Suckling pigs from an infected sow did not develop CMI responses, as measured by our system.

Agglutination Tests↗
PubMed1977

Detection of bovine leukemia virus in B-lymphocytes by the syncytia induction assay.

Bovine peripheral blood lymphocytes (PBL's) from 3 cows and 1 steer infected with bovine leukemia virus (BLV) were separated by fractionation through nylon wool columns into nylon-adherent and nonadherent cell populations. Nylon-adherent cells were enriched in B-lymphocytes, as determined by the presence of surface membrane immunoglobulins (slg), whereas nylon-nonadherent cells or "non-B-lymphocytes" contained few slg-bearing cells. PBL's and separated B- and non-B-lymphocyte populations were assayed for the presence of BLV by the induction of syncytia in bovine embryonic spleen cells. PBL's and B-lymphocyte populations both produced many syncytia, whereas non-B-lymphocytes yielded few or no syncytia. The specificity of syncytia formation by anti-BLV serum. PBL's from 2 control animals were negative for syncytia induction. This study presents further evidence that B-lymphocytes are the target cells for BLV infection.

Animals↗
PubMed1977

Epidemiology of mycobacterial lymphadenitis in an Idaho swine herd.

A study of Mycobacterium avium infected swine in an Idaho herd was made to obtain information on morbidity and to evaluate some control measures. Of 867 pigs slaughtered during a 30-day period in May and June, 1974, 100 carcasses were condemned or passed for cooking and 406 carcasses had lesions in one lymph node and were passed without restriction. Mycobacteriologic examinations were made on 33 pigs which were tuberculin tested. Mycobacterium avium was isolated from 21 of 26 tuberculin positive pigs and from 4 to 7 tuberculin negative pigs. Lymphocyte stimulation tests were completed for 12 pigs. Positive results were observed in 11 and M. avium was isolated from 7. Mycobacterium avium serotypes 1,2,4,8, and 9 were identified.

Animals↗
PubMed1977

Escape from antibody-mediated immune suppression in vitro by delayed-type hypersensitivity reaction.

Anti-sheep erythrocyte antiserum suppressed the in vitro immune response of swine spleen cells to sheep erythrocytes. Inhibition of the in vitro anti-sheep erythrocyte response was also observed in neonatal spleen cells, which were obtained from piglets recently fed colostrum. Addition of purified protein derivative (PPD) to spleen cell cultures prepared from animals previously sensitized to Mycobacterium bovis reversed the immunosuppression caused by passive antibody. Passive antibody regulation was dose dependent; low doses of anti-sheep erythrocyte antiserum caused enhancement, whereas higher doses resulted in complete inhibition of anti-sheep erythrocyte responses. Addition of PPD to cultures of sensitized cells containing passive antibody resulted in progressively increased antibody responses as the dose of anti-sheep erythrocyte antibody increased. PPD addition also reversed maternal antibody suppression of in vitro 2-week-old neonatal spleen cell responses providing these animals were sensitized with M. bovis at the time of birth.

Animals↗
PubMed1977

Regulation of the immune response in neonatal piglets by maternal antibody.

The ability of maternal antibody to regulate the humoral immune response to sheep erythrocytes and the hapten-carrier conjugate trinitrophenylated sheep erythrocytes (TNP-SRBC) was investigated in neonatal piglets. It was found that in this system, passively acquired maternal antibody would completely inhibit the in vitro primary immune response to SRBC while leaving the response the TNP intact. Data suggest that maternal antibody is regulating the in vitro response at the B-cell level since T-cell helper function to SRBC must not have been inhibited in order for an anti-TNP response to have occurred to TNP-SRBC. The regulation of immune responses by maternal antibody is temporary and disappears before 3 months of age.

Aging↗
PubMed1977

Characteristics of two new reticuloendotheliosis virus isolates of turkeys.

Reticuloendotheliosis (RE) virus strains MN81 and MN67 isolated from epiornithics of RE in turkeys were partially characterized. Strains MN81 and MN67 replicated in chicken embryo fibroblast,duck embryo fibroblast and turkey embryo-fibroblast cultures and produced syncytial cytopathic effects in duck embryo fibroblast and turkey embryo fibroblast cultures. The virions of MN81 and MN67 measured approximately 100 nm in diameter, resembled RE virus strain T, and could be distinguished from avian leukosis viruses morphologically. The buoyant density of strain MN81 was found to be 1.15 g/cm3 in sucrose gradients. Strains MN81 and MN67 were inactivated by heat, acid pH, ether, and chloroform treatments. These strains were serologically unrelated to avian leukosis virus but were related to RE virus strains T, CS, DIA, and SN.

Animals↗
PubMed1977

Evidence for the replication of bovine leukemia virus in the B lymphocytes.

Bovine peripheral blood lymphocytes from a cow with persistent lymphocytosis were separated on nylon wool columns into nylon-adherent and nonadherent populations. Nylon-adherent cells were highly enriched for surface immunoglobulin (SIg) bearing B lymphocytes (95.5%) and nonadherent cells for SIg negative non-B cells, presumably T lymphocytes (96.3%). The B lymphocytes were found to be the major producers for bovine leukemia virus. A total of 39% of the B-enriched cells, surviving after 72 hours in culture, produced bovine leukemia virus as compared with 0.5% of the non-B cells.

Animals↗
PubMed1977

Skin testing, fecal culture, and lymphocyte immunostimulation in cattle inoculated with Mycobacterium paratuberculosis.

Fourteen calves at 21 days of age were experimentally inoculated with 100 mg (wet weight) of Mycobacterium paratuberculosis. Three calves were inoculated orally, 4 intravenously, and 7 subcutaneously. Lymphocyte immunostimulation, fecal culture, and intradermal tuberculin skin testing were done between 112 to 150 days following exposure. Lymphocyte immunostimulation test results, conducted at 112 days after inoculation, showed all animals positive to Mycobacterium avium purified protein derivative. Fecal culture results, taken at 120 days after inoculation, showed that 2 of 3 animals inoculated intravenously were positive, whereas only 2 of 7 inoculated subcutaneously were positive (8 of 14 total were positive). Intradermal skin testing results at 150 days with M avium purified protein derivative showed 13 of the 14 calves were positive. Calves were examined at necropsy 153 days after inoculation, and M paratuberculosis was isolated from tissues of each of the 14 calves.

Animals↗