Differences in CD44 Surface Expression Levels and Function Discriminates IL-17 and IFN-γ Producing Helper T Cells
Julia Schumann1, Katarina Stanko1, Ulrike Schliesser1
1Institute of Medical Immunology, Charité University Medicine, Berlin, Germany.
Plos One
|July 15, 2015
Summary
CD44 expression levels distinguish T helper cell subsets, with IL-17 producing cells showing higher CD44 expression. CD44 is crucial for IL-17 induction, potentially acting as a co-stimulatory molecule by enhancing T cell receptor signaling.
Area of Science:
- Immunology
- Cell Biology
- T cell differentiation
Background:
- CD44 is a T cell activation marker involved in T cell receptor signaling.
- Understanding T helper cell subset differentiation is critical for immune response modulation.
Purpose of the Study:
- To investigate differences in CD44 expression between IFN-γ and IL-17 producing T helper cells.
- To determine the role of CD44 in the differentiation and function of these T helper cell subsets.
Main Methods:
- Stimulation of CD4+ T cells with allogeneic dendritic cells.
- Analysis of CD44 expression levels on T helper cell populations.
- Blocking CD44 function and assessing cytokine production (IL-17, IFN-γ).
- Investigating CD44's co-stimulatory role under varying stimulation conditions.
Main Results:
- IL-17 producing T helper cells predominantly expressed high levels of CD44 (CD44+++) compared to IFN-γ producing cells (CD44++).
- Blocking CD44 significantly reduced IL-17 secretion but had minimal impact on IFN-γ production.
- Under low stimulation conditions, CD44 could substitute for CD28 co-stimulation, promoting T helper 17 differentiation.
Conclusions:
- CD44 expression levels correlate with T helper cell subset identity, particularly favoring IL-17 producers.
- CD44 plays a critical role in the induction of IL-17 producing T helper cells by enhancing T cell receptor signaling.
- CD44 acts as a co-stimulatory molecule, essential for IL-17 differentiation, especially under suboptimal signaling environments.
