Animal models for human group 1 CD1 protein function. (February 2021) - Eckhardt, Emmelie
Highlights: Group 1 CD1 molecules are evolutionary conserved antigen presenting molecules that present lipid antigens to T cells. Mice and rats do not express goup 1 CD1 molecules, only recently transgenic mouse models became available. The functional importance of the type 1 CD1 system was demonstrated by animal models, such as guinea pigs, cattle and NHPs. Abstract: The CD1 antigen presenting system is evolutionary conserved and found in mammals, birds and reptiles. Humans express five isoforms, of which CD1a, CD1b and CD1c represent the group 1 CD1-molecules. They are recognized by T cells that express diverse αβ-T cell receptors. Investigation of the role of group 1 CD1 function has been hampered by the fact that CD1a, CD1b and CD1c are not expressed by mice. However, other animals, such as guinea pigs or cattle, serve as alternative models and have established basic aspects of CD1-dependent, antimicrobial immune functions. Group 1 CD1 transgenic mouse models became available about ten years ago. In a series of seminal studies these mouse models coined the mechanistical understanding of the role of the corresponding CD1 restricted T cell responses. This review gives a short overview of available animal studies and the lessons that have been and still can be learned.