Finally, by using primary microglia from IL-12 receptor β1-deficient (IL-12Rβ1−/−)
and IL-12Rβ2−/− mice, we demonstrate that IL-12 induces the expression of IL-7 in microglia and macrophages via both IL-12Rβ2 and IL-12Rβ1. These studies delineate a novel biological function of IL-12 that is absent in IL-23 and other p40 family members. “
“Similarly to Helicobacter PF-02341066 in vivo pylori but unlike Vibrio cholerae O1/O139, Campylobacter jejuni is non-motile at 20°C but highly motile at ≥37°C. The bacterium C. jejuni has one of the highest swimming speeds reported (>100 μm/s), especially at 42°C. Straight and spiral bacterial shapes share the same motility. C. jejuni has a unique structure in the flagellate polar region, which is characterized by a cup-like structure (beneath the inner membrane), a funnel shape (opening onto the polar surface) and less dense space (cytoplasm). Other Campylobacter species (coli, fetus, and lari) have similar motility and flagellate polar structures, albeit with slight differences. This is especially true for Campylobacter fetus, which has a flagellum only at one pole and a cup-like structure composed of two membranes. With the recently increasing consumption of poultry selleck chemicals and poultry products [1-3], Campylobacter, mainly C. jejuni, are the leading cause of bacterial food poisoning in Japan and in many other countries. In Japan, eating of raw animal products such
as chicken meat (“sasami”), chicken liver and cow liver is associated with Campylobacter infections. This organism is also one of the important causes of travelers’ diarrhea [4]. C. jejuni infection commonly causes enteritis, which can manifest as watery diarrhea or bloody RAS p21 protein activator 1 diarrhea with fever and abdominal cramps [5, 6]. It is also associated with systemic infections such as bacteremia and GBS [6, 7]. Death is rare [5]. In contrast to humans, C. jejuni are part of the normal flora of the intestines of chickens (which have a higher
body temperature, 42°C, than do humans) and are secreted into their stools. This organism almost never causes intestinal diseases in chickens [8]. C. coli is also associated with human infection, accounting for 1–25% of them [3]. Campylobacter jejuni is spiral in shape, has a single flagellum at each pole and exhibits high motility, this last feature being required for its colonization of animal and human test subjects [9]; motility is also important for C. jejuni adherence and invasion in vitro [10]. Over 40 genes are involved in biogenesis and assembly of C. jejuni flagella [11]; however, the bacterial polar structures responsible for their extremely high motility are not known. In this study, we examined the structures in the flagellate polar region of C. jejuni (and other Campylobacter species) by scanning and transmission electron microscopy to gain a better understanding of C. jejuni motility.