Regeneration and tolerance factor is expressed during T-lymphocyte activation and plays a role in apoptosis.

Abstract

Regeneration and tolerance factor (RTF) is a protein cloned from the thymus and expressed on B lymphocytes in normal pregnancy, B lymphocytic leukemia lines, and T and B lymphocytes in individuals with HIV infection. Findings, using the Jurkat T-cell model, revealed that RTF is upregulated after activation and anti-RTF antibody-induced apoptosis. In this article anti-RTF antibody-induced apoptosis of both unstimulated and activated T lymphocytes. RTF expression was examined in human PBMC or purified T lymphocytes after their in vitro activation. Kinetic studies indicated maximal RTF cell surface expression on activated T lymphocytes occurred between expression of the early activation antigen CD69 and the IL-2alpha receptor (CD25) by multiparameter flow cytometry. RTF receptor expression correlated with Fas (CD95) and CD25 receptor expression (r2 = 0.6 and 0.5, respectively). RTF surface expression was dependent on the stimuli used to activate T lymphocytes. T lymphocytes obtained maximal RTF expression when activated through the TCR signal complex using anti-CD3epsilon antibody alone when compared with T lymphocytes activated with costimulation provided by anti-CD28 antibody alone or with anti-CD28 and anti-CD3epsilon antibody. RTF is expressed under conditions of both activation and anergy. The RTFs increased concentration on the surface of anergic T cells may protect these cells from apoptosis because increased RTF concentrations inhibited anti-RTF induced apoptosis. These data further characterize the expression of RTF on activated T lymphocytes and the role of anti-RTF antibody in T-lymphocyte apoptosis.

• Authors: J S Boomer, R A Derks, G W Lee, B K DuChateau, A Gilman-Sachs, K D Beaman
• Journal: Human immunology (Hum Immunol) Vol. 62 Issue 6 Pg. 577-88 (Jun 2001) ISSN: 0198-8859 [Print] United States
• PMID: 11390032 (Publication Type: Journal Article)

Chemical References

• Annexin A5
• Antibodies, Monoclonal
• Antigens, CD
• Antigens, Differentiation, T-Lymphocyte
• CD69 antigen
• Lectins, C-Type
• Pregnancy Proteins
• Receptors, Interleukin-2
• Regeneration and tolerance factor, human
• Suppressor Factors, Immunologic
• fas Receptor

Topics

• Annexin A5 (biosynthesis)
• Antibodies, Monoclonal (immunology)
• Antigens, CD (biosynthesis)
• Antigens, Differentiation, T-Lymphocyte (biosynthesis)
• Apoptosis (immunology)
• Cell Membrane (immunology)
• Humans
• Jurkat Cells
• Kinetics
• Lectins, C-Type
• Leukocytes, Mononuclear (immunology)
• Lymphocyte Activation (immunology)
• Pregnancy Proteins (biosynthesis, immunology)
• Receptors, Interleukin-2 (biosynthesis)
• Suppressor Factors, Immunologic (biosynthesis, immunology)
• T-Lymphocytes (immunology)
• fas Receptor (biosynthesis)