We describe a systemic inflammatory response in human fetuses born to mothers with evidence of maternal anti-fetal rejection. The transcriptome and proteome of this novel type click here of fetal inflammatory response were different from that of FIRS type I (which is associated with acute infection/inflammation). “
“Control of intracellular
Salmonella infection requires Th1 priming and IFN-γ production. Here, we show that efficient Th1 priming after Salmonella infection requires CD11c+CD11bhiF4/80+ monocyte-derived dendritic cells (moDCs). In non-infected spleens, moDCs are absent from T-cell zones (T zones) of secondary lymphoid tissues, but by 24 h post-infection moDCs are readily discernible in these sites. The accumulation of moDCs is more dependent upon
bacterial viability than bacterial virulence. Kinetic studies showed that moDCs were necessary to prime but not sustain Th1 responses, while ex vivo studies showed that antigen-experienced moDCs were sufficient to induce T-cell proliferation and IFN-γ production via a TNF-α-dependent mechanism. Importantly, moDCs and cDCs when co-cultured induced superior Th1 differentiation than either subset alone, and this activity was independent of TNF-α. Thus, optimal Th1 development to Salmonella requires the rapid accumulation of moDCs within T zones and their collaboration with cDCs. Adaptive Th1 responses LDE225 mw are important for resolving intracellular bacterial infections such as those caused by Salmonella and Mycobacteria. Priming of CD4+ T cells occurs within the T-cell zones (T zones) of secondary lymphoid tissues and requires cognate interaction between dendritic cells (DCs) and naive CD4+ T cells 1. After priming, T cells upregulate Bay 11-7085 CD69 and CD44 and downregulate L-selectin (CD62L) and begin to proliferate. These events
occur rapidly after Salmonella Typhimurium infection (STm) 2 and are detectable within the first 24 h. In parallel, T cells can acquire Th1 features such as the capacity to produce IFN-γ 3. In the absence of Th1 differentiation and IFN-γ production, clearance of STm infections is markedly impaired and infection is more disseminated 4–10. DCs are the most potent APCs. As immature cells, DCs are strategically located in non-lymphoid tissues where they are likely to encounter antigen. After antigen encounter, DCs migrate to the T zones of secondary lymphoid tissues to present it to naive T cells. In secondary lymphoid tissues, in the steady state, several populations of resident DCs can be found and the role of these cells in priming T-cell responses has been studied 11, 12. Importantly, during infection or inflammation, another population of DCs differentiate from recruited blood monocytes. 13–16. These cells, monocyte-derived DCs (moDCs), are characterized by lower expression of CD11c than resident, conventional DCs (cDCs), yet they maintain monocyte markers such as CD115, Ly-6C and CD11b.