Human plasmacytoid dendritic cells (pDCs) are major producers of IFNalpha, are activated by CpG motifs, and are believed to enter lymph nodes (LNs) via L-selectin dependent extravasation across high endothelial venules. To identify a similar murine DC type, CD11c(+) cells in the LNs of L-selectin-deficient and control BALB/c mice were compared, revealing a population of CD11c(+)CD11b(-) cells t...

Although recent evidence has pointed to the role of organ- and pathogenesis-specific macrophage subsets, it is still unclear which subsets are critically involved in the pathogenesis of nonalcoholic steatohepatitis (NASH). Using melanocortin-4 receptor-deficient (MC4R-KO) mice fed Western diet (WD), which exhibit liver phenotypes similar to those of human NASH, we found a histological structure...

Immune cell accumulation in adipose tissue (AT) is associated with the development of AT inflammation, resulting in metabolic dysfunction. Circulating immune cell patterns may reflect immune cell accumulation in expanding AT. However, data linking human leukocytes in blood and AT is lacking. We investigated whether blood immune cell populations are associated with their counterparts in subcutan...

BACKGROUND Dendritic cells (DCs) mount tumor-associated antigens (TAAs), and the double-stranded RNA adjuvant Poly(I:C) stimulates Toll-like receptor 3 (TLR3) signal in DC, which in turn induces type I interferon (IFN) and interleukin-12 (IL-12), then cross-primes cytotoxic T lymphocytes (CTLs). Proliferation of CTLs correlates with tumor regression. How these potent cells expand with high qual...

The large inhibitory effect of IL-13 blockers on the asthma phenotype prompted us to ask whether IL-13 would play a role in regulating the allergic immune response in addition to its documented effects on structural pulmonary cells. Because IL-13 does not interact with murine T or B cells, but with monocytes, macrophages, and dendritic cells (DCs), we examined the role of IL-13 in the activatio...

Inflammation is a series of processes designed for eventual clearance of pathogens and repair of damaged tissue. In the context of autoimmune recognition, inflammatory processes are usually considered to be pathological. This is also true for inflammatory responses in the central nervous system (CNS). However, as in other tissues, neuroinflammation can have beneficial as well as pathological ou...

BACKGROUND Interleukin (IL)-19 has been reported to enhance chronic inflammatory diseases such as asthma but the in vivo mechanism is incompletely understood. Because IL-19 is produced by and regulates cells of the monocyte lineage, our studies focused on in vivo responses of CD11c positive (CD11c+) alveolar macrophages and lung dendritic cells. METHODOLOGY/PRINCIPAL FINDINGS IL-19-deficient ...

PURPOSE In addition to Langerhans cells (LCs), other dendritic cells (CD11c(+)) have recently been shown to express Langerin (c-type lectin). In skin, (non-LC) Langerin+ dendritic cells initiate adaptive immunity. However, whether such dendritic cells (DC) reside in the cornea, an immune-privileged tissue, is unknown. METHODS Normal C57BL/6 corneas were harvested for qRT-PCR analyses of Lange...

Although T-independent immunity is known to be generated against bacterial capsular and cell wall polysaccharides expressed by a number of bacterial pathogens, it has not been studied in depth during intracellular bacterial infections. Our previous study demonstrated that Ehrlichia muris, an obligate intracellular tick-borne pathogen, generates protective classical TI responses in CD4 T cell-de...

We previously reported that Mycobacterium tuberculosis triggers macrophage necrosis in vitro at a threshold intracellular load of ~25 bacilli. This suggests a model for tuberculosis where bacilli invading lung macrophages at low multiplicity of infection proliferate to burst size and spread to naïve phagocytes for repeated cycles of replication and cytolysis. The current study evaluated that mo...