title: Helper (OKT4) T cells from human T cell colonies produce potent colony-stimulating activity.
abstract: Confluent T cell colonies were grown by culturing blood mononuclear cells in double agar layers containing autologous plasma and phytohemagglutinin (PHA) for one week (37 degrees C, 5% CO2). The plates were then overlaid with serum-free alpha medium which was harvested after 24 h. This medium was demonstrated to have colony-stimulating activity (CSA) of greater potency than conventionally prepared PHA-leukocyte conditioned medium, which was prepared by incubating cells from the same donors. Removal of OKT4-positive cells using a monoclonal antibody and complement abolished CSA production by cells from T cell colonies while the removal of OKT8-positive cells had no effect.
mesh_terms: D000911:Antibodies, Monoclonal; D002999:Clone Cells / Q000378:metabolism; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D006801:Humans; D010835:Phytohemagglutinins / Q000494:pharmacology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D003115:Colony-Stimulating Factors; D010835:Phytohemagglutinins