STUDIES ON THE DIFFERENTIATION OF LYMPHOCYTES-T IN SHEEP .1. RECOGNITION OF A SHEEP LYMPHOCYTE-T DIFFERENTIATION ANTIGEN BY A MONOCLONAL-ANTIBODY T-80

  • 1 January 1983
    • journal article
    • research article
    • Vol. 49  (3) , 545-553
Abstract
Results demonstrate that a mouse IgM monclonal antibody (T-80) recognizes an antigen on cells of the T-lymphocyte lineage of sheep. This antibody does not identify all T cells, as 10-20% of thymocytes and some peripheral blood T cells are negative. T-80- thymocytes reside in the medulla. The majority of cortical thymocytes are T-80+ and classified as dull cellson the basis of antigen density per cell as measured by flow microfluorometry. T-80+ cells in the periphery can be categorized into 2 populations, i.e., dull cells and right cells. Suggestive evidence was obtained that bright T-80+ cells are fast recirculating T cells, whereas dull cells are sessile or less easily mobilizable T cells in the periphery. In fetal environment, over 90% of thymocytes and .apprx. 5% of spleen cells are T-80+ at 54 days of gestation (gestation period = 150 days), which may indicate that T-cell emigration from the thymus commences well before mid-gestation in sheep.