MITOGEN AND MIXED LYMPHOCYTE CULTURE RESPONSES OF ISOLATED BOVINE LYMPHOCYTE SUB-POPULATIONS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 42  (6) , 934-937
Abstract
Examinations were made of the mitogen and mixed lymphocyte culture (MLC) responses of subpopulations of bovine lymphocytes, isolated by density sedimentation following sequential E[erythrocyte]-rosetting with aminoethylisothiouronium bromide- and neuraminidase-treated sheep erythrocytes (EAET, EN). These procedures consistently separated 3 populations of E-rosetting T cells from a 4th population of non-E-rosetting cells (B and null cells). The isolated B and null cell population did not respond to phytohemagglutinin, concanavalin A, or pokeweed mitogen and responded minimally in mixed lymphocyte culture. Isolated T cells responded well to each of these stimuli. Differences in responsiveness were found among the 3 T cell populations isolated by differential rosetting. T cells with receptors for both EAET and EN rosette formation were the most responsive to the mitogens used and demonstrated maximum activity in MLC. T cells with only EAET receptors had equivalent activity in MLC and less activity in response to mitogens. Cells with only EN receptors were the least active T cell population in these assays. The different reactivities of these T cell populations in lymphoproliferative assays indicated that they represent distinct subsets of bovine T cells.