Identification of a uteroglobin-like antigen in human uterine washings

A uteroglobin-like molecule was detected with a sensitive radioimmunoassay for rabbit uteroglobin in the uterine washings of women. This antigen was detectable only in small amounts in the uterine washings obtained from women in the late luteal phase or proliferative phase, but was detected in large amounts in uterine washings of women collected during the early and midluteal phases of the ovarian-menstrual cycle. Our findings suggest that antigenically similar portions of rabbit uteroglobin have been phylogenetically conserved in women, and that endometrial production and secretion of this human uteroglobin-like antigen may be hormonally regulated.