EXPRESSION OF INTEGRINS IN MARMOSET (CALLITHRIX-JACCHUS) OVARY DURINGFOLLICULOGENESIS

Integrins were localized immunohistochemically in marmoset ovaries (Ca llithrix jacchus) of defined cycle stages. With monoclonal antibodies against beta 1, alpha 2, alpha 3, and alpha 6 integrin subunits, immun oreactivity was predominantly found in ovaries of the follicular phase , In the luteal phase, non-luteal cells, e.g. fibroblasts or endotheli al cells expressed beta 1, alpha 2, or alpha 6 integrins. Immunostaini ng for the beta 1 subunit was strongest in granulosa cells of all grow ing follicles. Weak immunoreactivity was found in granulosa cells of a tretic follicles, theca and interstitial cells. With the alpha 2 antib ody, binding was evident in granulosa cells of many, but not of all, p rimordial and primary follicles, Expression of alpha 2 was also found in luteinized granulosa cells of tertiary follicles, In growing follic les, immunoreactivity of alpha 3 was restricted to granulosa cells of early secondary follicles, Within the epithelium, staining was almost exclusively found in granulosa cells bordering on the basal granulosa cell layer, In advanced stages of atresia, granulosa cells of antral f ollicles expressed the alpha 3 subunit. Integrin alpha 6 expression wa s evident in granulosa cells of all growing follicles but was absent d uring advanced stages of degeneration, The specific expression pattern s of integrins suggest that these matrix receptors play a regulatory r ole during cyclic events in primate ovaries.