Related Experiment Videos
Purified lymphocyte function-associated antigen-3 (LFA-3) activates human thymocytes via the CD2 pathway
S M Denning1, M L Dustin, T A Springer
1Department of Medicine, Duke University School of Medicine, Durham, NC 27710.
Journal of Immunology (Baltimore, Md. : 1950)
|November 1, 1988
Summary
The CD2/LFA-3 pathway is crucial for thymocyte activation. LFA-3 antigen combined with specific antibodies and IL-2 or CD28 stimulation drives T cell proliferation in the thymus.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- Understanding thymocyte interactions with the thymic microenvironment is key to normal thymus function.
- The CD2/LFA-3 adhesion pathway is vital for thymocyte interactions with nonlymphoid cells.
- T cell activation via the CD2 pathway is essential for intrathymic T cell proliferation.
Purpose of the Study:
- To investigate the role of CD2/LFA-3 interactions in human thymocyte activation.
- To determine if LFA-3 antigen can induce thymocyte proliferation in vitro.
Main Methods:
- Purified LFA-3 antigen was used in in vitro assays.
- Thymocyte proliferation was measured with combinations of LFA-3 antigen, anti-CD2 antibody (CD2.1), and either rIL-2 or anti-CD28 antibody (Kolt2).
- Sheep red blood cells (SRBC) expressing the sheep homolog of LFA-3 (T11TS) were also used.
Main Results:
- LFA-3 antigen alone did not induce proliferation.
- LFA-3 antigen plus CD2.1 and rIL-2 significantly increased thymocyte proliferation.
- LFA-3 antigen plus CD2.1 and Kolt2 also induced thymocyte activation.
- Activation was LFA-3 antigen concentration-dependent and primarily affected mature thymocytes (CD1-).
- Intact SRBC with CD2.1 and rIL-2 also induced thymocyte activation.
Conclusions:
- The interaction between LFA-3 molecules and thymocyte CD2 molecules contributes to intrathymic thymocyte activation and proliferation.
- This pathway represents a significant mechanism for T cell development within the thymus.