Restrictin-P: the first member of a putative family of novel inhibitors

• Published in: Annals of the New York Academy of Sciences Vol. 628; p. 287
• Main Authors: Honigwachs-Sha'anani, J, Brosh, N, Kompier, R, Kadouri, A, Zipori, D
• Format: Journal Article
• Language: English
• Published: United States 01.07.1991
• Subjects: Animals; Cell Cycle - drug effects; Cell Line; Cytokines - genetics; Flow Cytometry; Glycoproteins - genetics; Glycoproteins - isolation & purification; Glycoproteins - pharmacology; Growth Inhibitors - genetics; Growth Inhibitors - isolation & purification; Growth Inhibitors - pharmacology; Plasmacytoma; RNA, Messenger - genetics; Transforming Growth Factor beta - pharmacology
• ISSN: 0077-8923
• DOI: 10.1111/j.1749-6632.1991.tb17259.x

MBA-2.1 cells produce an activity, designated restrictin-P, which is specifically inhibitory to the growth of plasmacytomas and mature B cell lymphomas. We examined whether the activity of this stromally derived glycoprotein could be attributed to a well-characterized growth factor. Restrictin-P-producing cells were therefore screened for the expression of transcripts of a variety of growth suppressors. With the exception of TGF-beta 1, none was produced in detectable amounts by these cells. Furthermore, recombinant forms of the inhibitory molecules tested did not exert a biological effect similar to that of restrictin-P. Restrictin-P was shown to elicit a G0/G1 arrest in the cell cycle of its target cells, as soon as 24 h after their exposure to the inhibitor. This effect could not be mimicked by TGF-beta 1. We suggest that restrictin-P is part of a novel family of inhibitors which are required for the maintenance of cell-type specificities in the hematopoietic microenvironment.