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Biomedical subjects

M R Shalaby

Publications and source records attributed to M R Shalaby.

40 records · Page 3Linked to original sources

Isolation of feline syncytia-forming virus from oropharyngeal swab samples and buffy coat cells.

Thirteen of 40 female cats were found to be chronically infected with feline syncytia-forming virus (FeSFV). Attempts to isolate the virus from these cats by conventional methods were not successful. However, virus was isolated from oropharyngeal swab samples and buffy coat cells. A new method was used involving inoculation of actively dividing Crandell feline kidney cell cultures. Cultures were trypsinized 3 days after inoculation and, as a result, cytopathic effect was amplified and ability to detect the virus was enhanced. The FeSFV was detected in 93% (92/88) of the oropharyngeal swab samples and 100% (14/14) of the buffy coat cell specimens. Feline sera were tested by immunodiffusion for precipitating antibody against FeSFV antigen. There was 100% correlation between viral infection and the presence of precipitating antibody. Virus and antibody persisted in infected cats for the duration of this study (8 months for 5 of the infected cats). Urolithiasis was observed in 15 of 28 male cats. Although a direct relationship between FeSFV infection and urolithiasis was not established, most of these male cats (20 of 21) had antibody to FeSFV.

Animals↗

Tumor antigen and human chorionic gonadotropin in CaSki cells: a new epidermoid cervical cancer cell line.

Epidermoid cervical carcinoma cells (CaSki line) have been established in continuous culture. When leukocytes from cervical cancer patients were incubated with CaSki culture fluid concentrates, inhibition of leukocyte migration was observed in more than 70 percent of the patients tested. By contrast, significantly less inhibition was observed with normal donor leukocytes or leukocytes from patients with other types of cancer. These results were consistent with the expression of tumor-associated antigen by CaSki cells. Analysis of the serum from the donor of the cell line at the time of tumor biopsy, and of CaSki culture fluids, demonstrated the presence of the beta subunit of human chorionic gonadotropin.

Adult↗

Effect of Crude and Purified hCG on Lymphocyte Blastogenesis.

Crude APL hCG completely inhibited blastogenesis induced by phytohemagglutinin, pokeweed mitogen, or concanavalin A in normal lymphocytes and lymphocytes obtained from cancer patients. Phenol in quantities comparable to its concentration in commercial lyophilized APL hCG also completely inhibited all three mitogenic responses. By contrast, similar doses of highly purified hCG had no inhibitory effect; higher concentrations produced only slight inhibition. Beta-hCG had a partial (less than 50%) inhibitory effect that was dose-independent and nonreproducible.

Chorionic Gonadotropin↗

Graft-vs.-host reaction in tissue culture.

The primary purpose of this study has been to validate the in vitro graft-vs.-host reaction as an experimental system. Time-dose studies have been presented for cells obtained from spleen, thymus, cortisone-treated thymus, inguinal lymph node, mesenteric lymph node, thoracic duct, and bone marrow cells. Both the degree of splenomegaly and the onset of spleen enlargement were found to be dependent on the number and source of cells tested. The effect of several immunosuppressive agents was examined. Amantadine was found to suppress completely the graft-vs.-host reaction in vitro when present at a concentration of 75 microg/ml. Pretreatment of effector cells with mitomycin C prevented their subsequent ability to cause a graft-vs.-host reaction. The effect of X irradiation on immunocompetence of spleen cells in vitro paralleled the known effect of irradiation on in vivo immunocompetence. Preimmunization did not increase the number or effectiveness of immunocompetent cells when measured under standard in vitro conditions. Preimmunization did, however, permit persistence of immunocompetence after immunosuppressive doses of X irradiation. Studies using congenic lines, moreover, indicated that the preimmunization effect could be demonstrated in strain combinations differing only in factors determined by the H-2 complex of genes. A weak graft-vs.-host reaction could be detected in strain combinations not involving differences at the H-2 locus. The potential of the in vitro graft-vs.-host reaction as a highly reproducible, quantifiable, internally controlled, and experimentally accessible system for study of such critical problems as cell differentiation and cell interactions is discussed.

Amantadine↗