Inverse Relationship Between Organ-Specific Autoantibodies and Systemic Immune Mediators in Type 1 Diabetes and Type 2 Diabetes: Action LADA 11

5th Framework Programme of EU and DeveloGen

Distinct monocyte gene-expression profiles in autoimmune diabetes

OBJECTIVE-There is evidence that monocytes of patients with type 1 diabetes show proinflammatory activation and disturbed migration/adhesion, but the evidence is inconsistent. Our hypothesis is that monocytes are distinctly activated/disturbed in different subforms of autoimmune diabetes. RESEARCH DESIGN AND METHODS-We studied patterns of inflammatory gene expression in monocytes of patients with type 1 diabetes (juvenile onset, n = 30; adult onset, n = 30) and latent autoimmune diabetes of the adult (LADA) (n = 30) (controls subjects, n = 49; type 2 diabetic patients, n = 30) using quantitative PCR. We tested 25 selected genes: 12 genes detected in a prestudy via whole-genome analyses plus an additional 13 genes identified as part of a monocyte inflammatory signature previously reported. RESULTS-We identified two distinct monocyte gene expression clusters in autoimmune diabetes. One cluster (comprising 12 proinflammatory cytokine/compound genes with a putative key gene PDE4B) was detected in 60% of LADA and 28% of adult-onset type 1 diabetic patients but in only 10% of juvenile - onset type 1 diabetic patients. A second cluster (comprising 10 chemotaxis, adhesion, motility, and metabolism genes) was detected in 43% of juvenile-onset type 1 diabetic and 33% of LADA patients but in only 9% of adult-onset type 1 diabetic patients. CONCLUSIONS-Subgroups of type 1 diabetic patients show an abnormal monocyte gene expression with two profiles, supporting a concept of heterogeneity in the pathogenesis of autoimmune diabetes only partly overlapping with the presently known diagnostic categories

Image-Guided Analyses Reveal that Non-CD4 Splenocytes Contribute to CD4 +

Recruitment of CD4 + T cells into islets is a critical component of islet inflammation (insulitis) leading to type 1 diabetes; therefore, determining if conditions used to treat diabetes change their trafficking patterns is relevant to the outcome. Cotransfer of CD4 + BDC2.5 (BDC) cells with non-CD4 splenocytes obtained from newly diabetic NOD mice, but not when they are transferred alone, induces accelerated diabetes. It is unclear whether these splenocytes affect diabetes development by altering the systemic and/or local trafficking and proliferation patterns of BDC cells in target and nontarget tissues. To address these questions, we developed an animal model to visualize BDC cell trafficking and proliferation using whole-body in vivo bioluminescence imaging and used the images to direct tissue sampling for further analyses of the cell distribution within tissues. The whole-body, or macroscopic, trafficking patterns were not dramatically altered in both groups of recipient mice. However, the local patterns of cell distribution were distinct, which led to invasive insulitis only in cotransferred mice with an increased number of islet-infiltrating CD11b + and CD11c + cells. Taken together, the non-CD4 splenocytes act locally by promoting invasive insulitis without altering the systemic trafficking patterns or proliferation of BDC cells and thus contributing to diabetes by altering the localization within the tissue