Modulation of dendritic cell differentiation by HLA-G and ILT4 requires the IL-6--STAT3 signaling pathway.

The expression of Ig-like transcript (ILT) inhibitory receptors is a characteristic of tolerogenic dendritic cells (DCs). However, the mechanisms of modulation of DCs via ILT receptors remain poorly defined. HLA-G is a preferential ligand for several ILTs.

Mechanisms of prolongation of allograft survival by HLA-G/ILT4-modified dendritic cells.

Engagement of inhibitory receptors on dendritic cells (DCs) is a powerful way to modulate their functions to achieve hyporesponsiveness or tolerance induction. Transgenic mice expressing human ILT4 receptor exclusively on DCs and triggered by HLA-G1 developed long-term survival of allogeneic skin transplant. Here we identify the cellular and molecular mechanisms responsible for that induction of hyporesponsiveness to alloantigen in vivo.

Regulation of protein kinase D during differentiation and proliferation of primary mouse keratinocytes.

Diseased skin often exhibits a deregulated program of the keratinocyte maturation necessary for epidermal stratification and function. Protein kinase D (PKD), a serine/threonine kinase, is expressed in proliferating keratinocytes, and PKD activation occurs in response to mitogen stimulation in other cell types. We have proposed that PKD functions as a pro-proliferative and/or anti-differentiative signal in keratinocytes and hypothesized that differentiation inducers will downmodulate PKD to allow differentiation to proceed.

Tolerization of dendritic cells by HLA-G.

The expression of HLA-G at the fetal-maternal interface during pregnancy and in transplanted tissue makes this a key molecule in the acceptance of a semiallogeneic fetus and allogeneic transplant. Dendritic cells (DC) play a critical role in the control of innate and adaptive immune responses. DC are present in maternal decidua, but must be kept under tight control.