title: Prss16 is not required for T-cell development.
abstract: PRSS16 is a serine protease expressed exclusively in cortical thymic epithelial cells (cTEC) of the thymus, suggesting that it plays a role in the processing of peptide antigens during the positive selection of T cells. Moreover, the human PRSS16 gene is encoded in a region near the class I major histocompatibility complex (MHC) that has been linked to type 1 diabetes mellitus susceptibility. The mouse orthologue Prss16 is conserved in genetic structure, sequence, and pattern of expression. To study the role of Prss16 in thymic development, we generated a deletion mutant of Prss16 and characterized T-lymphocyte populations and MHC class II expression on cortical thymic epithelial cells. Prss16-deficient mice develop normally, are fertile, and show normal thymic morphology, cellularity, and anatomy. The total numbers and frequencies of thymocytes and splenic T-cell populations did not differ from those of wild-type controls. Surface expression of MHC class II on cTEC was also similar in homozygous mutant and wild-type animals, and invariant chain degradation was not impaired by deletion of Prss16. These findings suggest that Prss16 is not required for quantitatively normal T-cell development.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, UC Davis Medical Center, 4150 V St., PSSB 3500, Sacramento, CA 95817, USA.
authors.forename: Saijai
authors.initials: S
authors.lastname: Cheunsuk
authors.forename: Zhe-Xiong
authors.initials: ZX
authors.lastname: Lian
authors.forename: Guo-Xiang
authors.initials: GX
authors.lastname: Yang
authors.forename: M Eric
authors.initials: ME
authors.lastname: Gershwin
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Gruen
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Bowlus
mesh_terms: D000818:Animals; D002678:Chimera / Q000235:genetics / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010641:Phenotype; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D013154:Spleen / Q000166:cytology; D016176:T-Lymphocyte Subsets; D013601:T-Lymphocytes / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology / Q000254:growth & development*
chemical_list: D000949:Histocompatibility Antigens Class II; C472502:PRSS16 protein, human; C472501:Prss16 protein, mouse; D012697:Serine Endopeptidases