Digalactosylceramide is the receptor for staphylococcal enterotoxin-B in human kidney proximal tubular cells

Abstract

We have characterized a glycosphingolipid (GSL) receptor for Staphylococcus enterotoxin-B (SEB) in cultured human kidney proximal tubular (PT) cells. Solid-phase binding of [125I]SEB to the GSL receptor was concentration dependent and was not displaceable by two structurally related toxins, such as staphylococcal enterotoxin-A and toxic shock syndrome toxin-1. Rat kidney cells did not bind [125I]SEB. However, when the rat kidney cells were pre-incubated with digalactosylceramide, there was a concentration-dependent binding of [125I]SEB. Trimethylsilyl derivatization of methyl glycosides, followed by gas-liquid chromatography-mass spectrometry (GC-MS), revealed that galactose was the major sugar component of this putative receptor GSL. The sphingosines present in this GSL were d18:2, d22:2 and d23:0; the fatty acids present were palmitate, oleate and stearate. Permethylation of alditol acetates and GC-MS revealed two predominant sugars, namely 2, 3, 4 and 6 tetramethylgalactital and 2, 3 and 6 trimethylgalactital. The GSL receptor for SEB was sensitive to alpha-galactosidase, and resistant to beta-galactosidase and beta-glucosidase. Taken together, our studies reveal that the tentative structure of the receptor for SEB in human kidney PT cells is CerGal alpha 1-->4Gal. In summary, we have identified a GSL as one of the binding sites of SEB, a food-borne toxin. We believe that our finding may open up rational approaches for the therapy of SEB-induced glycopathology in man.

Quantitative Determination of Globotriaosylceramide by Immunodetection of Glycolipid-Bound Recombinant Verotoxin B Subunit

“…It also may be useful in examining the role of GL-3 in various biological processes and disorders, such as cell growth (49), B cell differentiation (50) and apoptosis (51), cancer (52,53), ␣-interferon signaling (54 -56), interleukin-1␤, tumor necrosis factor-␤, hemolytic uremic syndrome (57)(58)(59), and familial dysautonomia (60). Similarly, an ELISA for staphylococcal enterotoxin-B also could be developed to quantitate digalactosylceramide (61), which also accumulates in Fabry disease (1).…”

The Staphylococcal Enterotoxins

“…Furthermore, synthetic peptide studies of enterotoxin activity reveal SE regions, previously not associated with TCR or MHC interactions, that block SE stimulation of T-lymphocyte proliferation (Harris et al, 1993a;Jett et al, 1994;Soos and Johnson, 1994;Hoffman etal., 1996). The same non-TCR peptide region (SEB 130-160) mimics SEB apoptotic activity in cultures of human kidney proximal tubule cells (Chatterjee and Jett, 1992;Chatterjee et al, 1995;Khullar and Chatterjee, 1995). This led to the hypothesis that multiple regions of the SEB molecule might play a role .…”

Isolation and Characterization of Major Glycoproteins of Pigeon Egg White

“…Bacterial enterotoxins, e.g. from E. coli (verotoxin) (15), Shigella dysenteriae Type 1 (Shiga toxin) (16), and Staphylococcus aureus (enterotoxin B) also specifically bind to these glycolipids (17). In contrast, glycoproteins with Gal␣1-4Gal were found only when the mammals were infected by tapeworm Echnococcus granulosus, in hydatid cyst fluid and membrane caused by the infection (18 -20).…”