Abstract: 219

LOCALIZATION OF MACROPHAGE MIGRATION INHIBITORY FACTOR (MIF) AND EXPRESSION OF MIF mRNA IN THE OVARY AND UTERUS OF PREGNANT AND NONPREGNANT SHEEP.

K Rath-Coursey¹ , S Bove^{1 *}, M Nishibori¹ , J Pate^{1 *}
Dept. of Animal Sciences, OARDC, Ohio State University, Wooster, OH ¹

Macrophage migration inhibitory factor (MIF) is a T cell and macrophage cytokine that stimulates macrophages, inhibits their migration away from sites of inflammation, and is required for antigen-dependent T cell proliferation. We demonstrated that MIF is present in the bovine corpus luteum, that it is localized to the large luteal cells, that the mRNA for MIF was highest in the early CL, and was also increased when the CL was induced to regress with prostaglandin. The purpose of this study was to determine if MIF expression was altered during maternal recognition of pregnancy and characterize MIF expression in other reproductive cells. Five pregnant and 5 nonpregnant sheep were sacrificed on day 14 of the estrous cycle or pregnancy. Corpora lutea, ovarian stroma and a variety of control tissues were processed for immunohistochemistry and isolation of RNA. MIF was localized in tissues using a specific rabbit anti-bovine MIF antibody validated for use with ovine tissue. MIF was localized to large luteal cells in CL of both pregnant and nonpregnant animals. Granulosa cells of secondary and tertiary follicles also stained intensely for MIF. Some primary follicles were MIF-positive. In the uterus, MIF was localized primarily in endometrial glands. MIF steady state mRNA expression was examined in CL by Northern blot and densitometric analysis. Very high expression was noted in 2 of 5 pregnant animals (76.83 & 104.17), causing a tendency toward greater MIF expression in pregnant animals, but average densitometric values for pregnant vs. non-pregnant animals were not significantly different (54.62 + 15.52 vs 38.74 + 3.44, n=5). In summary, the ovine CL contains MIF localized to the large luteal cells. Ovine granulosa cells also contain MIF. Differences in MIF expression were not observed between pregnant and nonpregnant animals.

    This abstract is being presented on Monday, August 2 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.