AUTHOR=Ciccarese Salvatrice , Burger Pamela A. , Ciani Elena , Castelli Vito , Linguiti Giovanna , Plasil Martin , Massari Serafina , Horin Petr , Antonacci Rachele TITLE=The Camel Adaptive Immune Receptors Repertoire as a Singular Example of Structural and Functional Genomics JOURNAL=Frontiers in Genetics VOLUME=10 YEAR=2019 URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2019.00997 DOI=10.3389/fgene.2019.00997 ISSN=1664-8021 ABSTRACT=
The adaptive immune receptors repertoire is highly plastic, with its ability to produce antigen-binding molecules and select those with high affinity for their antigen. Species have developed diverse genetic and structural strategies to create their respective repertoires required for their survival in the different environments. Camelids, until now, considered as a case of evolutionary innovation because of their only heavy-chain antibodies, represent a new mammalian model particularly useful for understanding the role of diversity in the immune system function. Here, we review the structural and functional characteristics and the current status of the genomic organization of camel immunoglobulins (IG) or antibodies, α/ß and γ/δ T cell receptors (TR), and major histocompatibility complex (MHC). In camelid humoral response, in addition to the conventional antibodies, there are IG with “only-heavy-chain” (no light chain, and two identical heavy gamma chains lacking CH1 and with a VH domain designated as VHH). The unique features of these VHH offer advantages in biotechnology and for clinical applications. The TRG and TRD rearranged variable domains of