Major advances in genomics and proteomics have prompted the creation of biological specimen collections and biobanks for use in biomedical research. These specimen collections and the wealth of data they generate will allow longitudinal studies to be conducted and subproducts such as DNA or RNA to be obtained. They may even be used in future studies.
View Article and Find Full Text PDFCD14, a GPI-linked membrane protein, is a component of the lipopolysaccharide (LPS) receptor complex, one of the pattern-recognizing receptors (PRR) expressed by myeloid lineage cells. Here we report that CD14, the functionally linked toll-like receptor molecules, TLR2 and TLR4, and the associated molecule MD-2 are expressed in endocrine cells of the human pancreatic islets. CD14 expression in human pancreatic islets was determined by immunofluorescence staining of tissue sections and primary cultures, and confirmed by flow cytometry of dispersed normal islets and SV40-transformed islet cells (HP62).
View Article and Find Full Text PDFClinical transplantation of human islets has a disappointingly low rate of success. We report here the identification of a possible causative factor: endotoxin present in the collagenase preparations used to disperse the pancreatic tissue before islet purification and transplantation. Supporting evidence includes (1) detection of unexpectedly high levels of endotoxin in most collagenase solutions currently used to digest human pancreases; (2) demonstration that supernatants generated during islet separation are able to induce the inflammatory cytokines interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-alpha) in macrophages; and (3) induction of IL-1, IL-6, and TNF-alpha in the islets during the separation procedure.
View Article and Find Full Text PDFAutoimmune thyroid diseases (AITD) and insulin-dependent diabetes mellitus (IDDM) are two autoimmune syndromes of unknown etiology with common immune features. One is that the target cells, thyrocytes and pancreatic islet beta cells respectively, hyperexpress several proteins encoded in the HLA region: HLA class I, HLA class II and transporter associated with antigen processing (TAP-1): the clinical course and many aspects of the immunopathology are, however, quite different. Low-molecular-mass polypeptides 2 and 7 (LMP2 and LMP7) are proteasome subunits that increase the efficiency of endogenous antigen processing and are encoded in close vicinity to the TAP genes.
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