Cells involved in the mitogen-induced helper function which facilitates the blastogenic response to Actinomyces viscosus

• Published in: Clinical immunology and immunopathology Vol. 19; no. 3; pp. 394 - 405
• Main Authors: Lopatin, Dennis E., Mangan, Dennis F., Horner, Irene S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.1981
• Subjects: Actinomyces - immunology; B-Lymphocytes - immunology; B-Lymphocytes - radiation effects; Cell Separation; Lymphocyte Activation; Mitogens - pharmacology; Pokeweed Mitogens - pharmacology; T-Lymphocytes - immunology; T-Lymphocytes - radiation effects
• ISSN: 0090-1229; 1090-2341
• DOI: 10.1016/0090-1229(81)90082-9

Coculture of human peripheral blood lymphocyte suspensions, previously pulsed with either pokeweed mitogen (PWM) or an Actinomyces viscosus ultrasonicate supernatant fraction (AV), resulted in a blastogenic response that was greater than the sum of the responses of the two independently cultured lymphocyte suspensions. Selective cobalt-51 irradiation of the precultured lymphocytes prior to coculture revealed that PWM was inducing a helper activity which facilitated the blastogenic response to the poorly mitogenic AV. Subsequent experiments revealed that both B- and T-enriched lymphocyte populations were capable of providing such help, however, the B-cell help appeared to require T-cell interaction. As few as one PWM-activated helper cell per 150 AV-pulsed cells was sufficient to provide measureable help. In the presence of PWM helper cells, both B and T cells gave strong blastogenic responses to AV fractions. Results of this study suggest that lymphocytes can respond to poorly mitogenic substances from bacteria if helper cell activity is provided by a second, unrelated lymphocyte stimulant.