Polysaccharides with sulfate groups are human T cell mitogens and murine polyclonal B cell activators (PBAs) II. Cellulose sulfate and dextran sulfate with two different lower molecular weights.

In our previous paper, we reported that various types of carrageenan, dextran sulfate and fucoidan, which are sulfated homopolysaccharides with high molecular weights, were human T cell mitogens and murine polyclonal B cell activators (PBAs) and that heparin, a sulfated heteropolysaccharide, was a very weak human mitogen and mouse PBA. Here we used cellulose sulfate (Mr 7-9 X 10(3], dextran sulfate with two different low molecular weights (Mr 5 X 10(3) and 8 X 10(3], two different condroitin sulfates (Mr 3.5 X 10(4], polyvinyl sulfate and polygalacturonic acid to investigate mitogenic activities of polysaccharides in detail. The following results were obtained. Low-molecular-weight sulfated homopolysaccharides, dextran sulfate and cellulose sulfate, were very weak or not human T cell mitogens. However, they were better murine PBAs. Sulfated heteropolysaccharides, chondroitin 4-sulfate and chondroitin 6-sulfate, hardly induced mitogenic changes in human T cells and mouse B cells, even though the molecular weight of these substances was more than 1 X 10(4). There were no other polymers examined so far which activated both human T cells and murine B cells. The relationship among molecular size, sulfate groups and lymphocyte activation is discussed in detail.