Biomedical subjects

E C Ren

Publications and source records attributed to E C Ren.

39 records · Page 3Linked to original sources

PubMed1982

Macrophage depletion using Cytodex.

Cytodex (microcarrier) beads were adapted for use as an adhering surface to deplete macrophages from a mouse spleen cell population. Non-adherent cells recovered from the incubation of one mouse spleen with 50 mg of Cytodex showed good viability and had markedly reduced proliferative response to the T cell mitogens phytohemagglutinin and concanavalin A. Response to lipopolysaccharide was, however, less clearly affected. Peritoneal exudate cells, and adherent cells recovered from the Cytodex by trypsinization, were able to restore the mitogenic response of non-adherent cells.

Animals↗

PubMed1981

Alpha-fetoprotein on human peripheral blood lymphocytes does not block complement-dependent lymphocytotoxicity.

Using a direct immunofluorescence assay, we showed that alpha-fetoprotein (AFP) both in purified form and in hepatocellular carcinoma (HCC) sera was capable of binding onto 10-20% of T lymphocytes and 5-10% of B lymphocytes in human peripheral blood when these lymphocytes were preincubated in AFP-positive fluids at 4 degrees C in the presence of sodium azide. But when the preincubation temperature was raised to 37 degrees C, most of the membrane-bound AFP was internalized or shed, and, consequently, less than 3% of the cells showed positive membrane fluorescence. In addition, binding of AFP onto lymphocyte surface membrane and the continuous presence of large amounts of AFP in these lymphocyte cultures did not interfere with the action of cytotoxic antibodies directed against HLA determinants on the lymphocyte surface.

Cells, Cultured↗

PubMed1981

Inhibition of lymphocyte proliferation by sera from patients with hepatocellular carcinoma: lack of correlation with serum alpha-fetoprotein levels.

Sera from 23 hepatocellular carcinoma (HCC) patients were studied for their effects on lymphocyte proliferation during polyclonal mitogen stimulation and one-way mixed lymphocyte culture (MLC). The effect of 25% HCC serum on tritiated thymidine uptake of cultures varied from slight augmentation to 95% inhibition; however, no relationship was found between the potency of inhibition and serum alpha-fetoprotein (AFP) concentration. Purified AFP from the ascitic fluid of an HCC patient had no effect on MLC or cultures containing pokeweed mitogen; but at a concentration of 200 micro g/ml, AFP inhibited up to 30% of the proliferative responses in cultures containing phytohemagglutinin or concanavalin A. Results strongly suggest that the AFP in HCC sera is not inhibitory in itself.

Blood↗