Schistosomal egg granuloma-derived fibroblast-stimulating factor is apparently distinct from interleukin-1.
We have previously reported that egg granulomas isolated from livers of Schistosoma mansoni-infected euthymic mice in vitro elaborate a factor(s) that stimulates a variety of fibroblast responses including fibroblast proliferation and enhanced synthesis of extracellular matrix proteins. We have postulated that these factors play a role in the pathogenesis of hepatic fibrosis in schistosomiasis mansoni. Serum-free supernatants from egg granuloma cultures also stimulate thymocyte proliferation in an assay that defects interleukin-1 (IL-1). Thymocytes and fibroblasts are stimulated to proliferate by the same fractions of egg granuloma culture supernatant separated by gel filtration, isoelectric focusing, and ion-exchange chromatography. This suggested that granuloma-derived IL-1 is responsible for the observed fibroblast stimulation. Here we report that the ability of granuloma culture supernatants to stimulate the IL-1-sensitive D10.G4.1 cells but not fibroblasts is removed by treatment with immobilized anti-IL-1 antibody. We also observed that dialyzed culture supernatants from egg granulomas obtained from infected congenitally athymic (nude) mice also stimulate fibroblast proliferation. Treatment with anti-IL-1 antibody did not abrogate this response. In contrast to our experience with egg granulomas isolated from euthymic mice, IL-1- and fibroblast-stimulating activity could be separated by gel filtration and isoelectric focusing. We conclude that the fibroblast growth-stimulating activities elaborated by egg granulomas from S. mansoni-infected euthymic and athymic mice may be different but both appear to be distinct from IL-1.
Prakash
S
S
Department of Medicine, New England Medical Center Hospitals, Boston, Massachusetts.
Dinarello
C A
CA
Danko
K
K
Stadecker
M J
MJ
Wyler
D J
DJ
D000818:Animals; D001681:Biological Assay; D002850:Chromatography, Gel; D005347:Fibroblasts; D006099:Granuloma / Q000503:physiopathology; D006133:Growth Substances / Q000302:isolation & purification / Q000502:physiology*; D007158:Immunologic Techniques; D007375:Interleukin-1 / Q000302:isolation & purification / Q000502:physiology; D007376:Interleukin-2 / Q000032:analysis; D015847:Interleukin-4; D007378:Interleukins / Q000032:analysis; D007526:Isoelectric Point; D051379:Mice; D008819:Mice, Nude; D012555:Schistosomiasis mansoni / Q000503:physiopathology*
D006133:Growth Substances; D007375:Interleukin-1; D007376:Interleukin-2; D007378:Interleukins; D015847:Interleukin-4