Unique T cell differentiation markers : gangliosides with cholera toxin receptor activity on murine fetal thymocytes

Abstract Cholera toxin B subunit receptors (CTBR; gangliosides GM1a and GM1b-GalNAc-Gal) and GM1b-type gangliosides were examined during T cell development in BALB/c mice by FACS or TLC immunostaining. Sixty-two percent of CD4 - 8 - early fetal thymocytes express CTBR [58% low affinity (GM1a + ), 4% high affinity (GM1a 2+ )] at 13 days gestation (Day 13); GM1a 2+ was expressed preferentially on Thy-1 + fetal thymocytes after Day 13. GM1a 2+ Thy-1 + cells increased from 4% on Day 13 to 95% on Day 17. Surface GM1a 2+ decreased beginning on Day 15 while GM1b-GalNAc-Gal (and CD4 and CD8) increased. GM1b-type 4 cells increased from 8% on Day 13 to 51% on Day 17 and then decreased to 16% at 4 weeks; few asialo GM1 + cells (