title: On the number and nature of antigen-sensitive lymphocytes in the blood of delayed-hypersensitive human donors.
abstract: The virus plaque assay has been successfully employed to enumerate antigen-sensitive cells in the peripheral blood lymphocyte populations of tuberculin-hypersensitive human donors. The method is based on the finding that, while resting lymphocytes are unable to produce a variety of viruses upon infection, lymphocytes activated by specific antigens become capable of virus replication. The average number of antigen-sensitive cells detected in cell populations from donors reacting to first test strength or intermediate test strength tuberculin was approximately 3.6/1000 lymphocytes, and the averages for both groups were similar. Studies on the kinetics of appearance of these virus plaque-forming cells and on the effects of the mitotic inhibitor, vinblastine, indicate that the activation of these antigen-sensitive cells is a linear process and that the cells must be nondividing cells during this process. These qualities contrast markedly with those described for the mitogenic response and the antibody-producing cells which require cell division and increase exponentially. On the basis of these experiments it is suggested that the antigen-sensitive cell measured in the virus plaque assay is the effector cell in delayed-type hypersensitivity reactions and, in addition, may be one of the cells critically involved in antibody formation.
mesh_terms: D000921:Antibody-Producing Cells; D001782:Blood Donors; D002247:Carbon Isotopes; D002452:Cell Count; D046508:Culture Techniques; D004247:DNA / Q000096:biosynthesis; D006462:Hemolytic Plaque Technique; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000097:blood*; D007111:Immunity, Cellular; D008214:Lymphocytes / Q000276:immunology*; D013936:Thymidine / Q000378:metabolism; D014373:Tuberculin / Q000494:pharmacology*; D014721:Vesicular stomatitis Indiana virus; D014747:Vinblastine / Q000494:pharmacology; D014779:Virus Replication
chemical_list: D002247:Carbon Isotopes; D014373:Tuberculin; D014747:Vinblastine; D004247:DNA; D013936:Thymidine