Table I.
Rat MHC molecules, expression levels and mAb staining profiles1
| Annotations | MHC-cluster | Accession numbers | Expression in YB 2/0 (anti-FLAG) | OX18 mAb | AAS1 mAb | AAS5 mAb | AAS6 mAb | 8G10 mAb |
|---|---|---|---|---|---|---|---|---|
| A1n | RT1-A | MG963095 | NA | +++ | +++ | − | +++ | − |
| A2n | RT1-A | MG963096 | +++ | ++ | − | − | − | − |
| A3n | RT1-A | MG963097 | ND | + | − | − | − | − |
| CE1 | RT1-CE | MG963098 | ++ | + | − | − | − | − |
| CE2 | RT1-CE | MG963099 | ++ | ++ | − | − | +/− | − |
| CE3 | RT1-CE | MG963100 | + | − | − | − | − | − |
| CE4 | RT1-CE | MG963101 | + | − | − | − | − | − |
| CE5 | RT1-CE | MG963102 | +/− | − | − | − | − | − |
| CE7 | RT1-CE | MG963103 | + | − | − | − | − | − |
| CE10 | RT1-CE | MG963104 | +/− | +/− | − | − | − | − |
| CE11 | RT1-CE | MG963105 | ND | − | − | − | − | − |
| CE12 | RT1-CE | MG963106 | ++ | ++ | − | − | − | − |
| CE13 | RT1-CE | MG963107 | + | − | − | − | − | − |
| CE14 | RT1-CE | MG963108 | ++ | ++ | − | − | − | − |
| CE15 | RT1-CE | MG963109 | + | − | − | − | − | − |
| CE16/Un | RT1-CE | MG963110 | ++ | ++ | ++ | ++ | ++ | − |
| Uc/d | RT1-CE | MG963112 | + | + | + | + | + | − |
| Ulv1 | RT1-CE | MG963113 | + | + | + | + | + | − |
| Uav1 | RT1-CE | MG963111 | + | + | + | + | + | − |
| Au | RT1-A | X82106 | +++ | +++ | − | − | − | − |
| Eu | RT1-CE | AJ306619 | + | − | − | − | − | + |
| Cl | RT1-CE | X70066.1 | + | ND | ND | ND | ND | − |
FLAG-tagged MHC class Ia and Ib molecules (A1n was not FLAG-tagged) were transfected into the rat YB2/0 cell line (expressing rat β2m) and tested for expression levels with anti-FLAG or different MHC reactive mAbs. Functional RT1-CE genes were cloned from BN strain rats expressing the reference n haplotype and are numbered according to their positioning in this class Ib gene cluster (RT1-CE6, -CE8, and -CE9 are pseudogenes and were not studied). The presumed alleles of RT1-CE16/Un were cloned from the c, d, lv1, and av1 haplotypes, and are designated Uc/d, Ulv1, and Uav1 (Uc and Ud were identical at DNA level). cDNA clones of Au, Eu and Cl (kindly provided by Etienne Joly, Toulouse, France) were subcloned into relevant expression constructs. Note that the broadly reactive mouse anti-rat mAb OX18 failed to stain several of the RT1-CE molecules in BN and the Eu molecule. The AAS1, AAS5, and AAS6 allo-mAbs reacted with all alleles of RT1-U, but not with the other RT1-CE molecules tested (CE1–15) or with RT1-Eu. The sequences can be accessed from https://www.ncbi.nlm.nih.gov/nuccore/. ND, not done; NA, not applicable.