Effects of mycoplasma infection on Fc receptors for IgE of rat basophilic leukemia cells

Abstract

Earlier studies from this laboratory had shown that rat basophilic leukemia cells carry two major receptors for IgE, named R and H, and a third minor receptor, designated 71K. It is now apparent that 71K is induced by the action of Mycoplasma hyorhinis, a common contaminant of tissue cultures. This induction is reversible. Decontamination either in in vitro or in vivo leads to a disappearance of 71K and re-infection causes its reappearance. The 71K receptor appears to be induced by the action of the mycoplasma on a surface molecule, most likely R, present on the cells at the time of infection. When receptors are occupied by IgE, 71K induction is inhibited. Other effects of mycoplasma infection include the significant reduction in the expression of transferrin receptors and increased histamine content of infected cells.

Mycoplasma‐induced degradation of IgE bound by Fcϵ receptors of rat basophilic leukemia cells

“…Diverse effects of mycoplasma infection on the immune system, both in vitro and in vivo, have been demonstrated . In addition to the effects observed in this laboratory [4], M . hyorhinis has been shown to be mitogenic for murine B lymphocytes [20] and to associate selectively with the Thy-1 and H-2 alloantigens of host T lymphocytes [21, 221.…”

“…The RBL cells used in this study have previously been described in detail [4]. Briefly, RBL-CA10 was a clone derived from RBLWpg and CA10.7 was a clone, which was mycoplasma free, obtained after gentamicin treatment of the mycoplasmapositive CAlO cells.…”

“…Subsequently, a 71-kDa FceR, designated 71K, was characterized and shown to be induced by infection of RBL cells with Mycoplasma hyorhink [3, 41. This induction was demonstrated to involve R receptors, present on the RBL cells at the time of infection. Saturation of R with IgE was found to inhibit the formation of 71K [4].…”

Detection of Mycoplasma Infection of Mammalian Cells

“…The effects of mycoplasma infection of mammalian cells varies depending on the species of mycoplasma, the degree of infection and the cell type. More specific effects of infection include preferential incorporation of nucleic acid precursors into mycoplasmal cells at the expense of host cells (5), secretion of collagenase by the host cell (7), interference with signal transduction (3), altered levels of IgE and transferrin receptors in basophilic leukemia cells (2) and increased secretion of soluble interleukin-2 receptor (6). Most, if not all, mycoplasma utilize arginine as an energy source mediated by the enzyme (Enzyme Commission No.…”

Phenotypic Changes among Hybrid Rat Mast Cells

“…containing 5% FCS and 0.05% Tween 20. After rinsing with TBS, the membrane was dried and aut oradiography was performed as described previously [16].…”