No evidence for PERV release by islet cells from German landrace pigs.

Background: Islet cells from pig could be used as an alternative to the current treatment of diabetic patients. However, xenotransplantation from pig to humans may be associated with the risk of transmission of porcine endogenous retroviruses (PERVs) that are present in the genome of all pigs and infect human cells in vitro. Although transplantation of pig islet cells for treatment of diabetes may be not accompanied by immunosuppression that may facilitate virus survival, since islets will be used encapsulated, it is nevertheless of importance to study whether islet cells release PERVs able to infect human cells during co-incubation.

Mitomycin C-treated dendritic cells inactivate autoreactive T cells: toward the development of a tolerogenic vaccine in autoimmune diseases.

Treatment of autoimmune diseases remains a challenge for immunological research. An ideal therapy should inhibit the immune reaction against the diseased organ and leave the rest of the immune response intact. Our previous studies showed that donor-derived dendritic cells (DCs) treated in vitro with mitomycin C (MMC) suppress rat heart allograft rejection if injected into recipients before transplantation.

Enhanced T-cell activation and T-cell-dependent IL-2 production by CD83+, CD25high, CD43high human monocyte-derived dendritic cells.

Although standardized protocols are widely used for the generation of monocyte-derived immunostimulatory dendritic cells (DC(ims)), the inducibility of Th1 cells by DC(ims) may considerably differ. As a measure for the quality of DC(ims) generated from an individual donor at a certain time point, CD83 is used in combination with HLA-DR and CD86 to assess DC maturation. When phenotypically analyzing DC(ims), we identified a subpopulation ( approximately 60%) of CD83+, CD86+, and HLA-DR+ DC(ims) that co-expressed CD25.

Immunosuppressive agents mediate reduced allostimulatory properties of myeloid-derived dendritic cells despite induction of divergent molecular phenotypes.

Immunosuppressive drugs such as glucocorticoids (dexamethasone (Dexa)), cyclosporin A (CsA) and tacrolimus (Tacro) have been shown to impair differentiation and/or function of immunostimulatory dendritic cells (DC(ims)). Phenotypes and functions of the resultant myeloid dendritic cells, however, have not yet been thoroughly elucidated. We show here that all DC subsets generated by treatment with immunosuppressive agents exhibited considerably reduced allostimulatory properties as measured in the primary mixed lymphocyte reaction (tacrolimus>cyclosporin A>dexamethasone, used at equimolar concentrations).

A gene signature of inhibitory MHC receptors identifies a BDCA3(+) subset of IL-10-induced dendritic cells with reduced allostimulatory capacity in vitro.

Dendritic cells (DC) are crucial gatekeepers in regulating immunity. Whereas mature immunostimulatory myeloid DC (DC(ims)) potently promote immune responses, IL-10-induced myeloid DC (DC-IL-10) counteract T cell activation. To elucidate the molecular repertoire by which DC-IL-10 secure reduced T cell activation, comparative gene expression profiling was done using Affymetrix U133A microarrays.

Stabilin-1 and -2 constitute a novel family of fasciclin-like hyaluronan receptor homologues.

MS-1, a high-molecular-mass protein expressed by non-continuous and angiogenic endothelial cells and by alternatively activated macrophages (Mphi2), and the hepatic sinusoidal endothelial hyaluronan clearance receptor are similar with respect to tissue distribution and biochemical characteristics. In the present study we purified these proteins by immuno- and hyaluronan-affinity chromatography respectively, sequenced tryptic peptides and generated full-length cDNA sequences in both mouse and human. The novel genes, i.