Effects of endotoxin-associated protein on hematopoiesis.
Endotoxin-associated protein (EAP), a gram-negative bacterial cell wall component, was evaluated for its effects on hematopoietic colony formation in vitro. Colony-stimulating activity, induced by EAP on circulating and bone marrow progenitor cells, was found to be partially mediated by T cells and augmented by interleukin-3. The addition of anti-human interleukin-1 (IL-1) antibodies reduced EAP activity, suggesting that EAP may induce IL-1 production. However, EAP was shown to promote the growth of mature progenitor cells independently, unlike the effects of IL-1 on the hematopoietic system. These studies demonstrate that bacterial components other than lipopolysaccharide, such as EAP, may have hematopoietic activity.
Porat
R
R
Department of Medicine, Ichilov Hospital, E. Souraski Medical Center, Tel Aviv, Israel.
Yanoov
M
M
Johns
M A
MA
Shibolet
S
S
Michalevicz
R
R
D001426:Bacterial Proteins / Q000494:pharmacology*; D002478:Cells, Cultured; D004731:Endotoxins / Q000494:pharmacology*; D006410:Hematopoiesis / Q000187:drug effects*; D006412:Hematopoietic Stem Cells / Q000187:drug effects; D006801:Humans; D007375:Interleukin-1 / Q000502:physiology; D007377:Interleukin-3 / Q000494:pharmacology; D008050:Lipid A / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000502:physiology
D001426:Bacterial Proteins; D004731:Endotoxins; D007375:Interleukin-1; D007377:Interleukin-3; D008050:Lipid A; C027315:lipid A-associated protein, Bacteria