The Forgotten: Identification and Functional Characterization of MHC Class II Molecules H2-Eb2 and RT1-Db2.
J Immunol
; 196(3): 988-99, 2016 Feb 01.
Article
em En
| MEDLINE
| ID: mdl-26740108
ABSTRACT
In this article, we report the complete coding sequence and to our knowledge, the first functional analysis of two homologous nonclassical MHC class II genes RT1-Db2 of rat and H2-Eb2 of mouse. They differ in important aspects compared with the classical class II ß1 molecules their mRNA expression by APCs is much lower, they show minimal polymorphism in the Ag-binding domain, and they lack N-glycosylation and the highly conserved histidine 81. Also, their cytoplasmic region is completely different and longer. To study and compare them with their classical counterparts, we transduced them in different cell lines. These studies show that they can pair with the classical α-chains (RT1-Da and H2-Ea) and are expressed at the cell surface where they can present superantigens. Interestingly, compared with the classical molecules, they have an extraordinary capacity to present the superantigen Yersinia pseudotuberculosis mitogen. Taken together, our findings suggest that the b2 genes, together with the respective α-chain genes, encode for H2-E2 or RT1-D2 molecules, which could function as Ag-presenting molecules for a particular class of Ags, as modulators of Ag presentation like nonclassical nonpolymorphic class II molecules DM and DO do, or even as players outside the immune system.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Antígenos de Histocompatibilidade Classe II
/
Antígenos de Histocompatibilidade
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2016
Tipo de documento:
Article