PT  - JOURNAL ARTICLE
AU  - Uede, T
AU  - Kohda, H
AU  - Yuasa, H
AU  - Osawa, H
AU  - Diamantstein, T
AU  - Yodoi, J
AU  - Ishii, Y
AU  - Kikuchi, K
TI  - 5C6-F4, a novel 100,000-dalton rat lymphocyte activation antigen defined by monoclonal antibody.
DP  - 1986 Jun 01
TA  - The Journal of Immunology
PG  - 3968--3976
VI  - 136
IP  - 11
4099  - http://www.jimmunol.org/content/136/11/3968.short
4100  - http://www.jimmunol.org/content/136/11/3968.full
SO  - J. Immunol.1986 Jun 01; 136
AB  - Con A-activated rat thymocytes were used to immunize mice, and immune spleen cells were fused with NS/1 myeloma cells. One clone, designated 5C6-F4, reacted strongly with Con A-activated rat thymocytes and some LPS-activated rat spleen cells but not with normal thymocytes, spleen cells, or bone marrow cells of rat origin. The 5C6-F4 did not react with Con A-activated thymocytes of mouse origin. Immunoprecipitation of 5C6-F4 antigen from surface-iodinated Con A-activated rat thymocytes or LPS-activated rat spleen cells revealed its m.w. to be approximately 100,000. The kinetic studies of the expression of 5C6-F4 antigen revealed that 5C6-F4 antigen was detectable at 6 hr after Con A stimulation of rat spleen cells, whereas IL 2 receptor (IL 2R) was detectable at 12 hr. The appearance of 5C6-F4 antigen and IL 2R precede the onset of DNA synthesis of Con A-activated spleen cells. Thus, 5C6-F4 antigen is classified as early activation antigen. The 5C6-F4 inhibits the lymphocyte proliferation induced by mitogen and the IL 2-driven rat T cell proliferation. Sequential immunoprecipitation study as well as binding inhibition study indicated that the 5C6-F4 antigen is distinct from IL 2R molecule. The 5C6-F4 antigen appears to be a novel rat lymphocyte activation antigen that exhibits immunoregulatory function and also may serve as a useful marker of T cell activation.