Differential expression patterns of glycosphingolipids and C-type lectin receptors on immune cells in absence of functional regulatory T cells

Abstract

Background: Glycosylation is a common and complex type of protein posttranslational modification. Altered glycosylation of immunoglobulins in autoimmune diseases has led to the "altered glycan hypothesis" postulating existence of a unique glycan signature on immune cells and extracellular proteins characterized by site-specific relative abundances of individual glycan structures and glycosylation patterns. However, it is not clear how glycosylation on leukocyte subpopulations differ between states of health or inflammation.

Hypothesis: Glycosphingolipid patterns on immune cells of forkhead-box-P3-deficient scurfy mice differs from those on wild-type immune cells.

Methods: T cells and dendritic cells were isolated from spleens of either wild-type or age-matched scurfy mice. Glycosphingolipids of CD4⁺ T cells and splenic dendritic cells from wild-type and scurfy mice were then analyzed by multiplexed capillary gel electrophoresis coupled to laser-induced fluorescence detection (xCGE-LIF). In addition, flow cytometry and ChipCytometry were used to access expression patterns of various C-type lectin receptors on antigen-presenting cells from various organs of both wild-type and scurfy mice.

Results: We, hereby report differential expression of glycosphingolipids in health and under inflammatory conditions as reflected in wild-type and scurfy mice. Furthermore, we observed that the absence of functional regulatory T cells correlated with elevated expression of CLEC-7A and CD205 but a reduction in levels of CLEC12A and CD206 on antigen-presenting cells.

Conclusion: We hereby show that the absence of functional regulatory T cells affects expression pattern and quantities of glycosphingolipids on immune cells. Thus, glycosphingolipids could serve as biomarkers for mapping genetical and homeostatic perturbances such as those resulting from a diseased condition.

Keywords: CD4+ T cells; FOXP3-deficient; dendritic cells; glycosphingolipids.