Cyclic variation of major histocompatibility complex class II antigen expression in the human fallopian tube epithelium.

OBJECTIVE

To systematically investigate the expression of major histocompatibility complex (MHC) class II antigens (human leukocyte antigens, HLA-DR, -DP, and -DQ) on columnar epithelium in the fallopian tube during the menstrual cycle.

STUDY

DESIGN

Biopsies were collected from the fallopian tube during laparotomy sterilization and immunoperoxidase staining was performed.

SETTINGS: Departments of Gynecology and Obstetrics and Clinical Immunology and Transfusion Medicine, Uppsala University, Uppsala, Sweden.

PATIENTS: Twenty healthy fertile women undergoing sterilization at different times of the menstrual cycle.

INTERVENTIONS: None.

MAIN OUTCOME MEASURES: The staining of the columnar epithelium was judged on a 4-graded scale according to the distribution of class II antigens.

RESULTS

A widespread preovulatory HLA-DR expression was observed almost completely lining the columnar epithelial cells including the luminal surface, whereas postovulatory the HLA-DR expression was withdrawn from the surface. The HLA-DP and -DQ antigens varied in a similar way, although not as pronounced.

CONCLUSIONS

The MHC class II antigen variation in the fallopian tube epithelium seen in this study may indicate a hormonal regulation that could reflect variable need for local immunocompetence during the menstrual cycle: a preovulatory need for immunoreactivity against invading microbes and postovulatory an optimal survival of the foreign preimplantation embryo.