Nos humanos, o xene que codifica esta proteína está localizado no cromosoma 11. Non hai un ligando claramente confirmado para este CD, aínda que o CD72, unha lectina de tipo C, considérase un posible ligando.
As células T expresan maiores niveis de CD5 ca as células B. O CD5 está regulado á alza nas células T tras unha activación forte. No timo, hai unha correlación entre a expresión de CD5 e a forza da interacción das células T cos péptidos propios.
Osman N, Ley SC, Crumpton MJ (1992). "Evidence for an association between the T cell receptor/CD3 antigen complex and the CD5 antigen in human T lymphocytes.". Eur. J. Immunol.22 (11): 2995–3000. PMID1385158. doi:10.1002/eji.1830221135.
Van de Velde H, von Hoegen I, Luo W; et al. (1991). "The B-cell surface protein CD72/Lyb-2 is the ligand for CD5.". Nature351 (6328): 662–5. PMID1711157. doi:10.1038/351662a0.
Jones NH, Clabby ML, Dialynas DP; et al. (1986). "Isolation of complementary DNA clones encoding the human lymphocyte glycoprotein T1/Leu-1.". Nature323 (6086): 346–9. PMID3093892. doi:10.1038/323346a0.
Lankester AC, van Schijndel GM, Cordell JL; et al. (1994). "CD5 is associated with the human B cell antigen receptor complex.". Eur. J. Immunol.24 (4): 812–6. PMID7512031. doi:10.1002/eji.1830240406.
Dianzani U, Bragardo M, Buonfiglio D; et al. (1995). "Modulation of CD4 lateral interaction with lymphocyte surface molecules induced by HIV-1 gp120.". Eur. J. Immunol.25 (5): 1306–11. PMID7539755. doi:10.1002/eji.1830250526.
Van de Velde H, Thielemans K (1996). "Native soluble CD5 delivers a costimulatory signal to resting human B lymphocytes.". Cell. Immunol.172 (1): 84–91. PMID8806810. doi:10.1006/cimm.1996.0218.
Dennehy KM, Broszeit R, Garnett D; et al. (1997). "Thymocyte activation induces the association of phosphatidylinositol 3-kinase and pp120 with CD5.". Eur. J. Immunol.27 (3): 679–86. PMID9079809. doi:10.1002/eji.1830270316.
McAlister MS, Davis B, Pfuhl M, Driscoll PC (1999). "NMR analysis of the N-terminal SRCR domain of human CD5: engineering of a glycoprotein for superior characteristics in NMR experiments.". Protein Eng.11 (10): 847–53. PMID9862202. doi:10.1093/protein/11.10.847.