Phenotypic determination of T-lymphocytes responding to chemotactic stimulation from fMLP,IL-8, human IL-10, and epidermal lymphocyte chemotactic factor

Summary Human T lymphocytes were collected after they had migrated towards N-formyl-methionyl-leukyl-phenylalanine (fMLP), rIL-8, human IL-10 (hIL-10), and epidermal lymphocyte chemotactic factor (ELCF). They were stained for determination of their phenotype by FACS analysis using anti-CD4, -CD8, -CD18, -CD45R0 and OPD4 antibodies. Human IL-10 increased the percentage of CD8⁺ T lymphocytes in the migrating cell population by 152% compared with cells migrating towards the medium and decreased the number of CD4⁺ T lymphocytes by 79%. ELCF increased the number of CD4⁺ T lymphocytes by 18%, and the number of CD45R0⁺ T lymphocytes by 52%, while the number of CD8⁺ T lymphocytes was decreased by 20%. rIL-8 increased the number of CD4⁺ T lymphocytes and decreased the CD8⁺ T lymphocytes. The distribution of the different subpopulations of T lymphocytes was not changed significantly by fMLP. The observed changes in the phenotypes did not occur when incubating T lymphocytes with the chemotaxins. Our observations demonstrate that individual chemotactic factors will attract specific subsets of T lymphocytes. They may help to explain the predominance of memory T lymphocytes (CD4R0⁺, CD4⁺) in allergic contact dermatitis and certain other skin diseases. They also confirm the results of a recent study, that showed hIL-10 to be selectively chemotactic for CD8⁺ T lymphocytes.