OBJECTIVE CD1 molecules present microbial and self glycolipid antigens to a defined T cell subset with features of natural killer cells. CD1 molecules are up-regulated by inflammatory stimuli such as GM-CSF, and we would expect to find increased CD1 expression in the synovium of patients with rheumatoid arthritis (RA) as compared to osteoarthritis (OA). This study was initiated to compare the d...

The presence of a silicone elastomer collar around one carotid artery of a rabbit induces thickening of the tunica intima. We used immunoblotting to study quantitatively changes in the isoforms of caldesmon, a protein implicated in the regulation of contractility in smooth muscle, while also monitoring the histological changes during 28 days after collaring. Control rabbit carotid arteries (n =...

Embryo electrofusion and tetraploid blastocyst microinjection is a modification of the traditional embryonic stem cell (ES cell)-based method to generate targeted mutant mice. Viability of tetraploid embryos is reportedly lower than with diploid embryos, with considerable interstrain variation. Here we assessed fetus and pup viability after ES cell microinjection of tetraploid blastocysts deriv...

The dsrE gene from Leuconostoc mesenteroides NRRL B-1299 was shown to encode a very large protein with two potentially active catalytic domains (CD1 and CD2) separated by a glucan binding domain (GBD). From sequence analysis, DSR-E was classified in glucoside hydrolase family 70, where it is the only enzyme to have two catalytic domains. The recombinant protein DSR-E synthesizes both alpha-1,6 ...

The recent discovery of dideoxymycobactin (DDM) as a ligand for CD1a demonstrates how a nonribosomal lipopeptide antigen is presented to T cells. DDM contains an unusual acylation motif and a peptide sequence present only in mycobacteria, but its discovery raises the possibility that ribosomally produced viral or mammalian proteins that commonly undergo lipidation might also function as antigen...

Crohn's disease is a chronic granulomatous inflammation of the gastrointestinal tract which was first described in the beginning of the 20th century. The histological similarity with intestinal tuberculosis has led to the assumption of an involvement of mycobacteria and mycobacterial antigens, respectively, in the etiology. A major defense mechanism against mycobacterial lipid antigens is the C...

The feline thymus is a target organ and site of viral replication during the acute stage of feline immunodeficiency virus (FIV) infection. This was demonstrated by histologic, immunohistologic, flow cytometric, and virologic tests. Thymic lesions developed after 28 days postinoculation (p.i.) and included thymitis, premature cortical involution, and medullary B-cell hyperplasia with germinal ce...

The repertoires of CD1- and MHC-restricted T cells are complementary, permitting the immune recognition of both lipid and peptide Ags, respectively. To compare the breadth of the CD1-restricted and MHC-restricted T cell repertoires, we evaluated T cell responses against lipid and peptide Ags of mycobacteria in leprosy, comparing tuberculoid patients, who are able to restrict the pathogen, and l...

CD1 proteins constitute a third class of antigen-presenting molecules. They bind lipids rather than peptides, and the T cells reactive to lipids presented by CD1 have been implicated in the protection against autoimmune diseases and infectious microorganisms and in the immune surveillance for tumors. Thus, the ability to identify, purify, and track the response of CD1-reactive cells is of param...