Isolation of immunologically active uterine luminal proteins associated with follicular and luteal phases of the ovary in buffalo (Bubalus bubalus)

Uterine luminal proteins (ULP) collected from the genital tract of buffalo during the follicular (Group F) and luteal (Group L) phases of the estrous cycle were chromatographed using sephacryl S-200 gel. Five peaks were detec ted in each group, Different protein concentrations (10 to 200 mu g) from P eaks I and V in each group were examined for immunological activity on poly morph nuclear leukocytic cells (PMNL) in vitro. All concentrations except 1 0 mu g of ULP Peak I (greater than or equal to 250 kDa) in Group F enhanced phagocytic activity of PMNL. Peak V (56 kDa) in the same group enhanced ph agocytic activity of PMNL only at low protein concentrations (10, 20 acid 4 0 mu g protein), while at greater concentrations (80, 150 and 200 mu g prot ein) PMNL activity was suppressed. On the other hand, all protein concentra tions from Peak I (greater than or equal to 250 kDa) in Group L suppressed PMNL activity in a dose-dependent manner. Proteins from Peak V (31 kDa) in Group L suppressed PMNL phagocytic activity at all concentrations but not t o the same extent as in Peak I. Electrophoretic analysis of Peaks I and V i n both groups revealed only 3 detectable protein bands (subunits) in Peak I and 1 detectable subunit in Peak V. Several additional proteins were proba bly not detected. The molecular weights of the detected subunits in Peaks I and V in Group F were greater than those in Group L as indicated by SDS-PA GE analysis. The results of this study show that ULP collected from buffalo possessed proteins that modulated phagocytic activity of PMNL in vitro. Pr oteins collected during the follicular phase, especially Peak I, enhanced p hagocytic activity of the PMNL, whereas those collected during the luteal p hase (Peaks I and V) suppressed activity. Changes in the molecular weights of ULP detected in this experiment may be related to the changes in phagocy tic activity of PMNL tested in vitro. (C) 1999 by Elsevier Science Inc.