Innate Immunity最新文献

The gasdermins (GSDM), a family of pore-forming proteins, consist of gasdermin A (GSDMA), gasdermin B (GSDMB), gasdermin C (GSDMC), gasdermin D (GSDMD), gasdermin E (GSDME) and DFNB59 (Pejvakin (PJVK)) in humans. These proteins play an important role in pyroptosis. Among them, GSDMD is the most extensively studied protein and is identified as the executioner of pyroptosis. Other family members have also been implicated in certain cancers. As a unique form of programmed cell death, pyroptosis is closely related to tumor progression, and the inflammasome, an innate immune mechanism that induces inflammation and pyroptosis. In this review, we explore the current developments of pyroptosis, the inflammasome, and especially we review the gasdermin family members and their role in inducing pyroptosis and the possible therapeutic values in antitumor effects.

M1/M2 macrophage polarization plays a pivotal role in the development of acute lung injury (ALI). The hypoxia-inducible factor-1α/pyruvate kinase M2 (HIF-1α/PKM2) axis, which functions upstream of macrophage polarization, has been implicated in this process. The function of HIF-1α is known to be tightly regulated by SUMOylation. Upregulation of SUMO-specific peptidase 3 (SENP3), a deSUMOylation enzyme, is induced by reactive oxygen species (ROS), which are abundantly produced during ALI. To explore the links between SENP3, macrophage polarization, and lung injury, we used mice with Senp3 conditional knockout in myeloid cells. In the lipopolysaccharide (LPS)-induced ALI model, we found that in vitro and in vivo SENP3 deficiency markedly inhibited M1 polarization and production of pro-inflammatory cytokines and alleviated lung injury. Further, we demonstrated that SENP3 deficiency suppressed the LPS-induced inflammatory response through PKM2 in a HIF-1α-dependent manner. Moreover, mice injected with LPS after PKM2 inhibitor (shikonin) treatment displayed inhibition of M1 macrophage polarization and reduced lung injury. In summary, this work revealed that SENP3 promotes M1 macrophage polarization and production of proinflammatory cytokines via the HIF-1α/PKM2 axis, contributing to lung injury; thus, SENP3 may represent a potential therapeutic target for ALI treatment.

Otitis media (OM) is the most common disease among young children and one of the most frequent reasons to visit the pediatrician. Development of OM requires nasopharyngeal colonization by a pathogen which must gain access to the tympanic cavity through the eustachian tube (ET) along with being able to overcome the defense mechanisms of the immune system and middle ear mucosa. OM can be caused by viral or bacterial infection. The three main bacterial pathogens are Streptococcus pneumoniae, nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis. Innate immunity is important in OM resolution as the disease occurs in very young children before the development of specific immunity. Elements of innate immunity include natural barriers and pattern recognition receptors such as Toll like receptors (TLRs), and Nod like receptors (NLRs). Surfactant proteins A (SP-A) and D (SP-D) act as pattern recognition receptors and are found in the lung and many other tissues including the ET and the middle ear where they probably function in host defense. Surfactant has a potential for use in the treatment of OM due to surface tension lowering function in the ET, and the possible immune functions of SP-D and SP-A in the middle ear and ET.

Ventilator associated pneumonia (VAP) caused by P. aeruginosa is a cause of morbidity and mortality in critically ill patients. The spread of pathogens with anti-microbial resistance mandates the investigation of novel therapies. Specific polyclonal anti-P. aeruginosa IgY-antibodies (Pa-IgY) might be effective for VAP caused by P. aeruginosa. The objective of this study was to investigate if intravenous Pa-IgY decreases the lower airway concentration of P. aeruginosa in VAP. We used a double blind randomized placebo controlled porcine model of VAP caused by P. aeruginosa. Eighteen pigs were randomized to either receive intravenous Pa-IgY or placebo. Repeated registration of physiological parameters and sampling was performed for 27 h. Concentration of P. aeruginosa in BAL-cultures was similar in both groups with 10^4.97 ± 10^2.09 CFU/mL in the intervention group vs 10^4.37 ± 10^2.62 CFU/mL in the control group at the end of the experiment. The intervention group had higher heart rate, cardiac index, oxygen delivery and arterial oxygen tension/fraction of inspired oxygen-ratio, but lower plasma lactate and blood hemoglobin levels than the control group. In summary, in an anesthetized and mechanically ventilated porcine model of VAP, Pa-IgY at the dose used did not decrease concentrations of P. aeruginosa in the lower airways.