CYCLIC VARIATION IN THE EXPRESSION OF FC-GAMMA RECEPTORS IN HUMAN ENDOMETRIUM

Cyclic variations of Fc gamma receptors (FcR) in human endometrium wer e studied in specimens from the fundal part, the lower part of the ute rine cavity and from the endocervix obtained in the proliferative, ovu latory and early and late secretory phase. The three classes of FcR we re studied using monoclonal antibodies (mAb) and indirect immunohistoc hemistry with avidin-biotin-peroxidase complexes. FcRI, FcRII and FcRI II were expressed on stromal cells throughout the cycle. In the late s ecretory phase some of the stromal cells had morphology comparable to predecidual cells. These cells express FcRIII only. FcRIII only were e xpressed on the glandular epithelium in all phases of the cycle. The e ndothelium was negative in the midcycle and positive early and late in the cycle for FcRI and FcRIII, although weak for FcRIII late in the c ycle. FcRII was not expressed on the endothelium. Apparently the FcR a ctivity in the endometrium does not vary during the menstrual cycle, e xcept for small variation in the expression on the endothelium and the presence of FcRIII on positive predecidual cells. No differences in F cR expression were found in specimens taken from different parts of th e uterine cavity.