The effects of fractions (Chalones) obtained from lymphoid organs on lymphocyte proliferation in vitro

Abstract

Aqueous extracts of lymphoid organs were prepared and fractionated by means of gel filtration, ion exchange chromatography, and isoelectric focusing. A protein-containing fraction with a molecular weight of approximately 80,000--90,000 and isoelectric points of 7.6 and 5.3--6.2 was isolated and shown to inhibit reproducibly both thymidine incorporation and proliferation of concanavalin A-stimulated mouse spleen lymphocytes in vitro. This effect appeared specific since proliferation of mastocytoma P-815 and leukemia L-1210 cells remained unaffected. A small molecular weight fraction (500 to 10,000 daltons) was also found to inhibit lymphocyte proliferation in vitro but was without apparent specificity for cell type.

Thymus derived inhibitor of lymphocyte proliferation III—Partial purification and characteristic biological activity

“…It has been reported that crude extracts from lymphoid tissue contain several unidentified, nonspecific suppressive factors (Hiestand et al, 1977;Blazsek & Gaal, 1978) as well as compounds like thymidine (Kasahara & ShioriNakano, 1976;Lenfant, Garcia-Giralt, Thomas & di Giusto, 1978) and the polyamines (Allen, Smith, Curry & Gaugas, 1977). Since these factors could interfere with the test systems used in our study, TCF was further purified by ion exchange chromatography.…”