Thymosin fraction 5: effects on T cell functions in mice immunosuppressed by severe dietary protein deficiency.
The present studies were performed to determine the effects of severe protein deficiency and subsequent injection of thymosin fraction 5 (TF5) on T and B cell functions. BALB/c mice, 4 weeks old, were fed a normal protein (21%), a low protein (4%) or a protein free (0%) diet and then injected with TF5 or buffer (PBS). A significant increase was observed in the PHA (phytohemagglutinin) and LPS (lipopolysaccharide) induced mitogenesis with increasing age of the well-nourished, PBS injected animals. The severely protein malnourished mice, PBS injected and the well nourished mice, injected with TF5 had smaller increases in both B and T cell mitogenesis with increasing age. TF5 injection of the malnourished mice increased PHA and LPS mitogenesis nearly to the levels of the well-nourished mice. The protein malnourished mice consistently had higher serum corticosteroid levels than controls. No changes in serum corticosteroids were observed with TF5 injection of controls, but there was a significant decrease in the corticosteroid levels of the severely malnourished with TF5 injection. Cytoxicity assays of T cell function, antibody dependent cellular cytoxicity and cytoxicity to mouse thymona tumor cells, in mice fed moderately protein deficient diets showed suppression compared to controls fed 20% protein. TF5 injection partially and temporarily increased these functions in the malnourished mice.
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D005260:Female; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009929:Organ Size / Q000187:drug effects; D011502:Protein-Energy Malnutrition / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013947:Thymosin / Q000031:analogs & derivatives* / Q000494:pharmacology
C033782:thymosin fraction 5; D013947:Thymosin