[New biological therapeutic options for the treatment of RE: inhibition of costimulatory molecules and blockade of Interleukin-6-interaction]

Neutralizing IL-6 reduces human arterial allograft rejection by allowing emergence of CD161+ CD4+ regulatory T cells

Perioperative injuries to an allograft exacerbate graft rejection, which in humans is primarily mediated by effector memory T cells. IL-6 transcripts in human coronary artery segments rapidly increase posttransplantation into immunodeficient mouse hosts compared with those of pretransplant specimens and fall dramatically by 30 d. Adoptive transfer of human PBMCs allogeneic to the artery 2 d postoperatively results in T cell infiltrates and intimal expansion 4 wk later. Ab neutralization of human IL-6 reduces the magnitude of intimal expansion and total T cell infiltration but increases the relative expression of CD161 while decreasing other Th17 markers. Coculture of MHC class II-expressing human endothelial cells (ECs) with allogeneic CD4(+) memory T cells results in T cell activation and EC secretion of IL-6. Neutralizing IL-6 in primary allogeneic T cell-EC cocultures results in enhanced T cell proliferation of CD161(+) CD4(+) T cells, reduces total T cell proliferation upon restimulation in secondary cultures (an effect dependent on CD161(+) T cells), increases expression of FOXP3 in CD161(+) T cells, and generates T cells that suppress proliferation of freshly isolated T cells. These data suggest that IL-6 released from injured allograft vessels enhances allogeneic T cell infiltration and intimal expansion in a model of human allograft rejection by inhibiting an increase in CD161(+) regulatory T cells.

Rheumatologie

The advent of monoclonal antibodies for the treatment of rheumatic diseases has revolutionized our understanding of therapeutic efficacy. Only a few years ago, response rates of >70% combined with significant reductions in inflammatory activity and radiologic progression would have been impossible. At the same time, however, issues of safety and cost have gained in importance and challenge physicians and patients alike. Making these new drugs available to as many eligible patients as possible requires a thorough documentation of disease activity using standardized outcome measures as well as a profound knowledge of their safety profiles. In addition, institutional guidelines for the use of these agents need to be as close to the cutting edge of science as possible. The following article presents an overview of currently available biologic agents in rheumatology and a prospect of those to come.