Inhibition of immune reactions in vivo by liposome associated transforming growth factor (TGF) type beta 1

• Published in: Clinical and experimental immunology Vol. 86; no. 3; pp. 532 - 536
• Main Authors: Strassmann, G, Bertolini, D R, Eidelman, O
• Format: Journal Article
• Language: English
• Published: England 01-12-1991
• Subjects: Analysis of Variance; Animals; Cell culture; Data processing; Dose-Response Relationship, Immunologic; Down-Regulation; Female; Gram-Positive Bacterial Infections - prevention & control; Hypersensitivity (delayed); Hypersensitivity, Delayed - prevention & control; Immune response; Immunosuppression - methods; Injections, Intravenous; Intravenous administration; Liposomes; Listeria monocytogenes; Listeriosis - prevention & control; Mice; Mice, Inbred C57BL; Organ Size - drug effects; Propionibacterium acnes; Spleen; Spleen - anatomy & histology; Splenomegaly - microbiology; Splenomegaly - therapy; Transforming Growth Factor beta - administration & dosage; Transforming Growth Factor beta - therapeutic use; Transforming growth factor- beta 1
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1111/j.1365-2249.1991.tb02965.x

In view of its potent inhibitory capacity on immune cells in culture, we wished to determine the ability of transforming growth factor (TGF) beta 1 to down-regulate immune responses in vivo. Preliminary experiments suggested that, at the doses used, systemic injection of soluble TGF beta 1 could not affect bacterial-induced spleen enlargement in mice. Therefore, we sought to utilize a physiochemical property of this molecule, namely its high pI, to determine possible association between the ligand and preformed liposomes possessing an opposite charge. TGF beta 1 was preferentially associated with negatively charged, but not with neutral, liposomes. These TGF beta 1 associated liposomes were able to deliver a suppressive signal to indicator cells in vitro. Intravenous injection of TGF beta 1, associated with liposomes possessing an opposite charge, into mice immunized with heat-killed Corynebacterium parvum significantly reduced the size of the spleen as well as the number of splenocytes. Systemically administered TGF beta 1 associated liposomes could also inhibit delayed type hypersensitivity reactions to Listeria monocytogenes. These data suggest that appropriately administered, TGF beta 1 can inhibit immune responses in vivo.