A Novel Subset of Anti-Inflammatory CD138+ Macrophages Is Deficient in Mice with Experimental Lupus.

Dead cells accumulating in the tissues may contribute to chronic inflammation. We examined the cause of impaired apoptotic cell clearance in human and murine lupus. Dead cells accumulated in bone marrow from lupus patients but not from nonautoimmune patients undergoing myeloablation, where they were efficiently removed by macrophages (MΦ). Impaired apoptotic cell uptake by MΦ also was seen in mice treated i.p. with pristane (develop lupus) but not mineral oil (MO) (do not develop lupus). The inflammatory response to both pristane and MO rapidly depleted resident (Tim4+) large peritoneal MΦ. The peritoneal exudate of pristane-treated mice contained mainly Ly6Chi inflammatory monocytes; whereas in MO-treated mice, it consisted predominantly of a novel subset of highly phagocytic MΦ resembling small peritoneal MΦ (SPM) that expressed CD138+ and the scavenger receptor Marco. Treatment with anti-Marco-neutralizing Abs and the class A scavenger receptor antagonist polyinosinic acid inhibited phagocytosis of apoptotic cells by CD138+ MΦ. CD138+ MΦ expressed IL-10R, CD206, and CCR2 but little TNF-α or CX3CR1. They also expressed high levels of activated CREB, a transcription factor implicated in generating alternatively activated MΦ. Similar cells were identified in the spleen and lung of MO-treated mice and also were induced by LPS. We conclude that highly phagocytic, CD138+ SPM-like cells with an anti-inflammatory phenotype may promote the resolution of inflammation in lupus and infectious diseases. These SPM-like cells are not restricted to the peritoneum and may help clear apoptotic cells from tissues such as the lung, helping to prevent chronic inflammation.

[Genetic mutation screening of glucose-6-phosphate dehydrogenase deficiency in Dongguan district].

OBJECTIVE: To determine the incidence and genotypes of glucose-6-phosphate dehydrogenase (G6PD) deficiency in Dongguan region of Guangdong Province and assess the efficacy and feasibility of flow-through hybridization. METHODS: Peripheral blood samples were randomly selected and detected by modified G6PD/6PGD ratio method. Flow-through hybridization was used to detect 14 G6PD mutations among all samples. RESULTS: In total 1005 samples were collected, the detection rate for modified G6PD/6PGD ratio method and flow-through hybridization were 2.79% and 20.90%, respectively. The consistency of the two methods was poor(Kappa=0.187). When c.1311C>T mutation is excluded, the consistency of the two methods was good for males (Kappa=0.952) but still poor for females (Kappa=0.194). The most common mutations were c.1376G>T, c.1388G>A and c.95A>G. No G6PD deficiency was found among those only carrying the c.1311C>T mutation. CONCLUSION: Flow-through hybridization can simultaneously detect 14 loci, covering over 90% of common mutations in Chinese population, and can be easily expanded. The routine method may miss many females carrying homozygous, compound heterozygous and heterozygous mutations, but the detection rate for male hemizygous mutation was much higher.

Soybean polysaccharide fermentation products regulate the air-liquid interface in co-cultured Caco-2 cells by increasing short chain fatty acids transport.

Soybean polysaccharides have a large molecular weight and complex structure, which is not conducive to body absorption and exerting their biological activities. After the in vitro hydrolysate digestion of soybean polysaccharides, their interactions with intestinal epithelial cell monolayers during soybean polysaccharide-derived short chain fatty acids (SCFAs) uptake and transport were determined by co-culturing soybean polysaccharide hydrolysate products with Caco-2 cells. Based on prepared soybean polysaccharide hydrolysates, physicochemical indices and hydrolysate components were explored and the interface characteristics between SCFAs and Caco-2 cells were characterized using interfacial rheology methods for the first time. Transwell chambers were used to explore relationships between SCFAs transport and the air-liquid interface in Caco-2 cells. We showed that physicochemical properties, cell proliferation rates, and the interfacial tension of soybean polysaccharide hydrolysis products were related to fermentation times, with differences observed between the two hydrolyzed soybean polysaccharides (microwave ammonium oxalate soy hull polysaccharides (MASP) and soluble soy polysaccharides (SSP)). MASP outperformed SSP in terms of total sugar utilization and added cellular value by intestinal flora. Hydrolyzed soybean polysaccharides decreased interfacial tension with increasing hydrolysis times when modulating the interfacial properties of a Caco-2 cell co-culture system. SCFAs translocation rates increased with fermentation time, from 0 h to 24 h. Also, a negative correlation was observed between SCFAs translocation rates and interfacial tension. Our data provide a foundation for the intestinal absorption of soybean polysaccharides and at the same time bring new insights into the interactions between polysaccharides and food in the future, promoting the application of polysaccharides in food processing and even medicine.

Pharmacological inhibition of the mammalian target of rapamycin pathway suppresses acquired epilepsy.

Inhibition of mTOR by rapamycin has been shown to suppress seizures in TSC/PTEN genetic models. Rapamycin, when applied immediately before or after a neurological insult, also prevents the development of spontaneous recurrent seizures (epileptogenesis) in an acquired model. In the present study, we examined the mTOR pathway in rats that had already developed chronic spontaneous seizures in a pilocarpine model. We found that mTOR is aberrantly activated in brain tissues from rats with chronic seizures. Furthermore, inhibition of mTOR by rapamycin treatment significantly reduces seizure activity. Finally, mTOR inhibition also significantly suppresses mossy fiber sprouting. Our findings suggest the possibility for a much broader window for intervention for some acquired epilepsies by targeting the mTOR pathway.

Genetic screening involving 101 hot spots for neonates not passing newborn hearing screening and those random recruited in Dongguan.

In order to investigate essential molecular causes for hearing loss and mutation frequency of deafness-related genes, 1315 newborns who did not pass the Newborn Hearing Screening (NHS) (audio-no-pass) and 1000 random-selected infants were subjected to detection for 101 hotspot mutations in 18 common deafness-related genes. Totally, 23 alleles of 7 deafness genes were detected out. Significant difference (χ2 = 25.320, p = 0.000) existed in causative mutation frequency between audio-no-pass group (81/1315, 6.160%) and random-selected cohort (18/1000, 1.80%). Of the genes detected out, GJB2 gene mutation was with significant difference (χ2 = 75.132, p = 0.000) between audio-no-pass group (417/1315, 31.711%) and random-selected cohort (159/1000, 15.900%); c.109G > A was the most common allele, as well as the only one with significantly different allele frequency (χ2 = 79.327, p = 0.000) between audio-no-pass group (392/1315, 16.84%) and random-selected cohort (140/1000, 7.55%), which suggested c.109G > A mutation was critical for newborns' hearing loss. This study performed detection for such a large scale of deafness-associated genes and for the first time compared mutations between audio-no-pass and random-recruited neonates, which not only provided more reliable DNA diagnosis result for medical practioners and enhanced clinical care for the newborns, but gave more accurate estimation for mutation frequency.

Liver X Receptor Agonist Therapy Prevents Diffuse Alveolar Hemorrhage in Murine Lupus by Repolarizing Macrophages.

The generation of CD138+ phagocytic macrophages with an alternative (M2) phenotype that clear apoptotic cells from tissues is defective in lupus. Liver X receptor-alpha (LXRα) is an oxysterol-regulated transcription factor that promotes reverse cholesterol transport and alternative (M2) macrophage activation. Conversely, hypoxia-inducible factor 1-α (HIF1α) promotes classical (M1) macrophage activation. The objective of this study was to see if lupus can be treated by enhancing the generation of M2-like macrophages using LXR agonists. Peritoneal macrophages from pristane-treated mice had an M1 phenotype, high HIFα-regulated phosphofructokinase and TNFα expression (quantitative PCR, flow cytometry), and low expression of the LXRα-regulated gene ATP binding cassette subfamily A member 1 (Abca1) and Il10 vs. mice treated with mineral oil, a control inflammatory oil that does not cause lupus. Glycolytic metabolism (extracellular flux assays) and Hif1a expression were higher in pristane-treated mice (M1-like) whereas oxidative metabolism and LXRα expression were higher in mineral oil-treated mice (M2-like). Similarly, lupus patients' monocytes exhibited low LXRα/ABCA1 and high HIF1α vs. CONTROLS: The LXR agonist T0901317 inhibited type I interferon and increased ABCA1 in lupus patients' monocytes and in murine peritoneal macrophages. In vivo, T0901317 induced M2-like macrophage polarization and protected mice from diffuse alveolar hemorrhage (DAH), an often fatal complication of lupus. We conclude that end-organ damage (DAH) in murine lupus can be prevented using an LXR agonist to correct a macrophage differentiation abnormality characteristic of lupus. LXR agonists also decrease inflammatory cytokine production by human lupus monocytes, suggesting that these agents may be have a role in the pharmacotherapy of lupus.