Abstract:
:Invariant natural killer T (iNKT) cells recognize self lipid antigens presented by CD1d molecules. The nature of the self-antigens involved in the development and maturation of iNKT cells is poorly defined. Lysophospholipids are self-antigens presented by CD1d that are generated through the action of phospholipases A1 and A2. Lysosomal phospholipase A2 (LPLA2, group XV phospholipase A2) resides in the endocytic system, the main site where CD1d antigen acquisition occurs, suggesting that it could be particularly important in CD1d function. We find that Lpla2(-/-) mice show a decrease in iNKT cell numbers that is neither the result of a general effect on the development of lymphocyte populations nor of effects on CD1d expression. However, endogenous lipid antigen presentation by CD1d is reduced in the absence of LPLA2. Our data suggest that LPLA2 plays a role in the generation of CD1d complexes with thymic lipids required for the normal selection and maturation of iNKT cells.
journal_name
Proc Natl Acad Sci U S Aauthors
Paduraru C,Bezbradica JS,Kunte A,Kelly R,Shayman JA,Veerapen N,Cox LR,Besra GS,Cresswell Pdoi
10.1073/pnas.1302923110subject
Has Abstractpub_date
2013-03-26 00:00:00pages
5097-102issue
13eissn
0027-8424issn
1091-6490pii
1302923110journal_volume
110pub_type
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