Interleukin 7 (murine pre-B cell growth factor/lymphopoietin 1) stimulates thymocyte growth: regulation by transforming growth factor beta.
The effects of interleukin 7 (IL7) previously known as murine pre-B cell growth factor/lymphopoietin 1 on the growth of murine thymocytes was investigated. In the presence of a suboptimal dose of phytohemagglutinin, IL7 induced a dose-dependent increase in thymocyte proliferation which was comparable to that induced by IL1. Additionally IL7 was shown to synergize with a suboptimal dose of IL1 to enhance thymocyte proliferation. Thymocyte proliferation induced by IL7, like that induced by IL1, was inhibited when either recombinant transforming growth factor (TGF) beta 1 or beta 2 were added at the initiation of culture. Interestingly, IL7-driven thymocyte proliferation was considerably less susceptible to inhibition by TGF-beta 1 or TGF-beta 2 than that induced by IL1. Taken together these results suggest IL7 may activate distinct populations of thymocytes and/or act through a pathway distinct from that utilized by IL1.
Chantry
D
D
Charing Cross Sunley Research Centre, Hammersmith, London, GB.
Turner
M
M
Feldmann
M
M
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004357:Drug Synergism; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology; D015851:Interleukin-7; D007378:Interleukins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008808:Mice, Inbred CBA; D013601:T-Lymphocytes / Q000166:cytology*; D013950:Thymus Gland / Q000166:cytology; D015291:Transforming Growth Factors / Q000494:pharmacology*
D007375:Interleukin-1; D015851:Interleukin-7; D007378:Interleukins; D015291:Transforming Growth Factors