1. Academic Validation
  2. Effect of phospholipase A2 inhibitors on mouse T lymphocytes. I. Phospholipase A2 inhibitors exert similar immunological activities as glycosylation inhibiting factor

Effect of phospholipase A2 inhibitors on mouse T lymphocytes. I. Phospholipase A2 inhibitors exert similar immunological activities as glycosylation inhibiting factor

  • Int Immunol. 1989;1(4):425-33. doi: 10.1093/intimm/1.4.425.
H Ohno 1 M Iwata T Nakamura K Ishizaka
Affiliations

Affiliation

  • 1 Department of Medicine, Johns Hopkins University, School of Medicine, Good Samaritan Hospital, Baltimore, MD 21239.
Abstract

Since our previous experiments suggested that glycosylation-inhibiting factor (GIF) is a phosphorylated derivative of a Phospholipase inhibitory protein, we determined whether other well-known Phospholipase inhibitors may have similar biological activities. The results showed that Phospholipase A2 (PLA2) inhibitors, such as recombinant human lipocortin I and ONO-RS-082, could switch T cell hybridoma 12H5 cells from the formation of glycosylated IgE-binding factors (IgE-BF) to the formation of unglycosylated IgE-BF, whereas neomycin, a Phospholipase C Inhibitor, failed to affect the nature of IgE-BF formed by the cells. The minimum concentrations of lipocortin I and ONO-RS-082 required for switching the 12H5 cells to the formation of unglycosylated IgE-BF were comparable to or less than IC50 of the inhibitors for PLA2. The ability of partially purified GIF to switch the 12H5 cells to the formation of unglycosylated IgE-BF was markedly enhanced by treatment of the preparation with Alkaline Phosphatase. It was also found that lipocortin I and ONO-RS-082, but not neomycin, facilitated the generation of GIF-producing T cells. When spleen cells of ovalbumin (OVA)-primed BDF1 mice were stimulated with homologous antigen and the activated T cells were propagated by recombinant IL-2 in the presence of GIF, lipocortin I, or ONO-RS-082, T cells obtained in the cultures constitutively produced their own GIF. Antigenic stimulation of the T cells induced the formation of unglycosylated IgE-BF and GIF with an affinity for OVA.(ABSTRACT TRUNCATED AT 250 WORDS)

Figures
Products