SOME BIOCHEMICAL RESPONSES OF BUFFALO PMN CELLS TO VARIOUS STIMULI

In view of great species differences in biology of polymorphonuclear c ells, and nonavailability of basic data on buffalo PMN cells for asses sing their functional activity, the present work on the immune-defence system involving protein synthesis and O-2(-) production was undertak en to highlight the immunomodulatory role of thyroxine. Digitonin, LPS and Con-A activation generated superoxide, which was monitored by NBT reduction. The study suggested that concanvalin A (Con-A) and T-4 wer e able to synergetically increase the production of superoxide and H2O 2. The likely involvement of thyroxine in activation was studied by [I -125]thyroxine incorporation, which was significantly increased due to activation. In contrast, aflatoxin B-1 together with Con-A caused a s ignificant decrease (P < 0.05) in incorporation of [I-122]T-4. Optimum time dependence in [C-14]leucine incorporation by buffalo PMN cells w as found to be 30 min and the factors like T-4 (7.7 ng/ml) and glutath ione (400 mu g/ml) significantly enhanced the incorporation. In contra st, antiinflammatory agent, indomethacin (40 mu g/ml) inhibited protei n synthesis in PMN cells; while puramycin also significantly lowered t he [C-14]leucine incorporation. Total [C-14]leucine incorporation in a cid extractable cationic proteins and peptides, known for their antiba cterial properties was found to be 30-40% when separated on AU-PAGE. T he studies revealed the in vitro immunomodulatory role of T-4 in O-2(- ), H2O2 production and cationic protein synthesis by the activated PMN cells of buffalos.