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Biomedical subjects

C C Muscoplat

Publications and source records attributed to C C Muscoplat.

At least 91 records · Page 5Linked to original sources
PubMed1977

In vitro stimulation of bovine peripheral blood lymphocytes: suppression of phytomitogen and specific antigen lymphocyte responses by aflatoxin.

The effects of aflatoxin B1 on responses of the peripheral blood lymphocytes (PBL) of 2 normal animals to phytohemagglutinin, concanavalin-A, and pokeweed mitogen and of the PBL of 2 Mycobacterium bovis-infected animals to phytohemagglutinin and purified protein derivative of M bovis (PPD) were studied. Aflatoxin concentrations of greater than or equal to 10 microgram/ml significantly suppressed the lymphocyte response of normal animals to the phytomitogens. Lymphocyte response of M bovis-infected animals to specific antigen PPD was significantly suppressed at aflatoxin concentration of 0.5 microgram/ml. Fifty- to 100-fold higher concentrations of aflatoxin were required to produce 50% suppression of lymphocyte response to phytomitogens, as compared with that produced to PPD.

Aflatoxins↗
PubMed1977

Enhancement of phytohemagglutinin and concanavalin A responses of splenic lymphocytes by adherent cell removal.

Removal of glass wool-adherent cells resulted in an enhancing effect on DNA synthesis as measured by increased [3H]-thymidine uptake by normal swine spleen cells stimulated with phytohemagglutinin or concanavalin A (Con A). Depletion of nylon-adherent cells caused decreased DNA synthesis in response to Con A, except at high doses of Con A, whereas similar cultures stimulated with phytohemagglutinin showed enhanced DNA synthesis throughout the dose range employed. Titration experiments revealed that enhancing effects of adherent cell removal are most pronounced at higher cell and mitogen concentrations. Glass wool was more efficient than nylon in the enhancement of mitogen-induced DNA synthesis.

Animals↗
PubMed1976

Experimentally induced Mycobacterium avium serotype 8 infection in swine.

Five of 6 swine experimentally inoculated with Mycobacterium avium serotype 8 had microgranulomas in the cervical or mesenteric lymph nodes at necropsy 92 days later. In vivo tuberculin skin reactivity and in vitro lymphocyte immunostimulation responses were evaluated at 10 and 12 weeks after the pigs were inoculated. Positive responses were obtained on both tests in inoculated pigs, whereas test results in noninoculated pigs and pigs given killed bacterial cells were negative. Mycobacterium avium serotype 8 was isolated at necropsy from the cervical or mesenteric lymph nodes of each of the pigs inoculated with viable microorganisms and from the 2 pigs kept in the pen with inoculated swine. Mycobacteria were not isolated from tissues of the noninoculated swine or those given killed cells.

Animals↗
PubMed1976

Mechanism of protection from primary bovine viral diarrhea virus infection. I. The effects of dexamethasone.

A series of investigations was designed to study the role of cellular immunity and passive antibody in protecting neonatal calves from primary bovine viral diarrhea virus infection. Administration of corticosteroids (dexamethasone) in doses capable of suppressing cellular immunity markedly potentiated systemic bovine viral diarrhea virus infection in calves which lacked bovine viral diarrhea passive neutralizing antibody. Immunosuppressed calves did not form neutralizing antibody to bovine viral diarrhea virus and developed a fatal viremia. Calves with high levels of passive bovine viral diarrhea neutralizing antibodies were protected from the effect of corticosteroids. The results suggest an essential role for humoral passive antibody, but not for cellular immunity, in protection from primary systemic bovine viral diarrhea virus infection in calves.

Animals↗
PubMed1976

Enhancement of humoral immune responses. I. Potentiating influence of purified protein derivative on the invitro immune response of spleen cells sensitized to Mycobacterium bovis and Mycobacterium avium.

Addition of purified protein derivate (PPD) to suspension cultures of spleen cells from swine sensitized to Mycobacterium bovis and Mycobacterium avium resulted in marked enhancement of antisheep erythrocyte plaque-forming cells after stimulation with sheep erythrocytes. The enhancing effect appeared early in the response and was specific for the sensitizing antigen. The enhancing effect was dependent upon the presence of both sheep erythrocytes and PPD in the culture system. PPD had no effect in the absence of sheep erythrocytes. Addition of PPD to cells from nonsensitized animals did not produce any enhancing effect.

Adjuvants, Immunologic↗
PubMed1975

Development of specific in vitro lymphocyte responses in cattle infected with Mycobacterium bovis and with Mycobacterium avium.

Two calves infected with Mycobacterium avium and another 2 with Mycobacterium bovis were studied for development and specificity of lymphocyte activation responses and skin reactivity to purified protein derivatives (PPD). Lymphocytes cultured in vitro from infected calves manifested significant uptake of tritiated thymidine in response to the PPD prepared from the homologous organisms, whereas heterologous PPD produced little or no stimulation. The time of appearance of specifically sensitized lymphocytes was studied, as was the specificity of skin reactivity.

Animals↗
PubMed1975

Development of specific lymphocyte immunostimulation and tuberculin skin reactivity in swine infected with Mycobacterium bovis and Mycobacterium avium.

Swine infected with Mycobacterium bovis and Mycobacterium avium were studied for development and specificity of lymphocyte immunostimulation and tuberculin skin reactivity to purified protein derivatives (PPD) of tuberculins. Lymphocytes from infected animals had maximal blastogenic responses to PPD prepared from the homologous organisms. The time of appearance of specifically sensitized lymphocytes was studied, as was the specificity of skin reactivity. In vitro lymphocyte responses of M avium serotype 1-infected swine to M avium serotype 1 PPD were greater than were the responses of M avium serotype 2-infected swine to the same antigen. Results indicate that the specific stimulation of sensitized lymphocytes might prove useful in the diagnosis of tuberculosis in swine and in differentiating infections due to different serotypes of M avium.

Administration, Oral↗
PubMed1975

Effects of corticosteroids on responses of bovine peripheral blood lymphocytes cultured with phytohemagglutinin.

Corticosteroids given in vivo altered the response of lymphocytes in the peripheral blood of calves. Lymphocytes were cultured and stimulated in vitro with phytohemagglutinin (PHA). After an initial suppression of lymphocyte responses to PHA, there was a rapid return to normal. It is concluded that, in calves, short-term, high-dose immunosuppressive therapy with corticosteroids produces a population of lymphocytes resistant to corticosteroids, possibly by destruction of corticosteroid-sensitive lymphocytes.

Animals↗
PubMed1975

Comparison of lymphocyte stimulation and tuberculin skin reactivity in Mycobacterium bovis-infected Macaca mulatta.

Lymphocyte immunostimulation tests were conducted on Mycobacterium bovis-infected and tuberculin-negative rhesus macaques (Macaca mulatta), using purified protein derivative (PPD) tuberculins prepared from strains of Mycobacterium tuberculosis and Mycobacterium avium. The stimulation of lymphocytes with M tuberculosis PPD was significantly greater for the M bovis-infected macaques than for the noninfected controls (P smaller than 0.05). The response of lymphocytes from M bovis-infected macaques to stimulation with M tuberculosis PPD was greater than the responses to stimulation with M avium PPD (P smaller than 0.01). The results of in vitro lymphocyte stimulation and tuberculin skinreactivity were similar.

Animals↗
PubMed1974

Macrophage-dependent lymphocyte immunostimulation in cattle infected with Mycobacterium bovis and with Mycobacterium avium.

Cultures of bovine peripheral blood leukocytes were prepared from calves inoculated with Mycobacterium bovis and with M. avium. Suitable lymphocyte stimulation was obtained with specific and nonspecific mycobacterial mitogens. Leukocyte cultures depleted of adherent, macrophage-type cells did not respond to stimulation with purified protein derivative, although they were responsive to phytohemagglutinin.

Animals↗