Inhibitory effect of medium sized molecules from patients with renal failure on lymphocyte stimulation by phytohemagglutinin.

Middle molecular weight molecules were separated from uremic sera by chromatography on Sephadex G25 fine and assayed on lymphocyte cultures stimulated by phytohemagglutinin. They were found to inhibit markedly the cell proliferation by this mitogen, and this inhibition was still noticeable when cells were incubated for only one hour with eluate, before the culture. These molecules, as well as methylguanidine, might play a part in the cell-mediated immunodeficiency secondary to renal failure.