Selective Impairment of Cell Antigenicity by Fixation

Abstract

Abstract The effects of fixation by formaldehyde, p-formaldehyde, and glutaraldehyde on H-2a and Moloney leukemia virus (MLV)-associated antigens were evaluated. Two cell types were employed: a) a MLV-induced lymphoma, YAC, which is passaged in ascites form in A/Sn mice or grown in long-term culture, and b) MLV-infected A/Sn and BALB/c mouse fibroblast monolayers. Antigenicity of the suspension cells was assessed by conventional absorbtions of antisera of predetermined titers to H-2a and MLV, and subsequent titration of these absorbed antisera by the 51Cr release cytotoxicity test against pertinent target cells. Antigenicity of fibroblast monolayers was assessed directly by a mixed hemadsorption technique. At low concentrations and short fixation periods, p-formaldehyde selectively impaired MLV antigens, preserving H-2a. At high concentrations and longer fixation periods, p-formaldehyde markedly reduced H-2a antigenicity while preserving MLV antigens. Fixation of either suspension cells or monolayers with glutaraldehyde (0.25% for 5 min at 20°C) markedly impaired both types of antigenicity.