Studies on the nature and cellular distribution of TLMA — a major rat T axis differentiation antigen Identification as the glycosphingolipid GgOse₄Cer (asialo GM₁)

Abstract

The recently detected T axis differentiation antigen, which was provisionally designated as T-lymphocyte-macrophage-associated antigen (TLMA) could now be identified as the neutral glycosphingolipid GgOse4Cer (asialo-GM1). TLMA is not only expressed on lymphocytes on the T lineage and on macrophages of the rat, but also on eosinophilic cells. On erythrocytes, the determinants are only detectable after neuraminidase treatment. Within the cell surface of thymic lymphocytes, the antigen determinant is partly masked by sialic acid residues. Presently, it cannot be decided whether the masking effect is brought about by sialic acid residues of adjacent glycolipid molecules or whether a nonreactive sialylated precursor molecule exists.

Localization of a Glycosphingolipid, Asialo GM1, in Rat Immunocytes1

“…Thus, as it is possible to consider the' presence of glycoprotein which cross-reacts with anti-asialo GM1 antibody, it is necessary to visualize asialo GM1 in these myeloid cells. A band corresponding to asialo GM1 was detected in macrophages, as shown previously by a microdetection method (6). This band showed the same migration as asialo GM1 obtained by acid hydrolysis of rat erythrocyte GM1 ganglioside (unpublished data).…”

“…On the other hand, an unknown ganglioside (indicated by a single star) was detected in granulocytes but not in macrophages, and another unknown glycolipid (indicated by double stars) which was detected in glycolipids of macrophages, was not visualized in glycolipids of granulocytes on thin layer chromatogram under the conditions used in this experiment. were recently characterized as asialo GMl immunologically by absorption of cytotoxic of anti-TLMA antiserum and chemically by a microchemical detection method (6,7). Both results clearly showed that asialo GMl has the character of TLMA.…”

“…Furthermore, this antigen has been shown to be expressed not only on lymph node lg" cells by also on peritoneal exudate macrophages (5). Therefore, asialo GM1 has been considered to be a common antigen of rat T lymphocytes, in particular mature T cells and macrophages (6). The visualization by the chemical microdetection method using fluorography of a band corresponding to asialo GM1 on a thin-layer chromatogram confirmed that asialo GM1 is actually present in rat thymocytes, lymph node lg-cells and macrophages, but not in lg+ cells or erythrocytes (7).…”

The Role of Glycosphingolipids in Immune Cell Functions

“…In murine and rat T cells, quantification of neutral GSLs has revealed that the amount of neutral GSLs was higher in peripheral T cells compared to thymocytes. The major neutral GSLs in thymocytes are globosides while asialo GM1 is the most abundant neutral GSL in mature T cells (58, 69, 130, 131). In addition, some unique neutral GSLs, such as Galα1-3(F(2))ASGM1, have been detected in rat thymocytes (110).…”

Gangliotetraosylceramide is a major glycolipid of epithelial cells of mouse small intestine

“…Antibodies to gangliotetraosylceramide abolished the natural killer activity [5-71 and enhanced the growth of lymphoma in vivo [7]. In the rat this glycolipid has been identified not only on T lymphocytes but on macrophages and eosinophilic cells as well [8,9].…”