Search

Type IV collagen is an integral component of basement membranes. Mutations in COL4A1, one of the key genes encoding Type IV collagen, can result in a variety of diseases. It is clear that a significant proportion of mutations that affect splicing can cause disease directly or contribute to the susceptibility or severity of disease. Here, we analyzed exonic mutations and intronic mutations described in the COL4A1 gene using bioinformatics programs and identified candidate mutations that may alter the normal splicing pattern through a minigene system. We identified seven variants that induce splicing alterations by disrupting normal splice sites, creating new ones, or altering splice regulatory elements. These mutations are predicted to impact protein function. Our results help in the correct molecular characterization of variants in COL4A1 and may help develop more personalized treatment options. [ABSTRACT FROM AUTHOR]

Aim: To investigate the association between periodontal macrophage polarization states and the alveolar bone levels, and to assess whether glycosylated nano‐hydroxyapatites (GHANPs) could improve bone regeneration in periodontitis by inducing macrophage M2 polarization. Materials and Methods: The change of macrophage polarization state in inflammatory periodontal tissues (with bone loss) was examined using clinical gingival samples. The relationship between macrophage phenotype and bone level in periodontal bone loss and repair was evaluated using a mouse periodontitis model. The effect of GHANPs on macrophage polarization was assessed by the in vitro model of lipopolysaccharide (LPS)‐stimulated inflammation. The polarization‐related markers were detected by immunofluorescence staining, real‐time polymerase chain reaction and enzyme‐linked immunosorbent assay analysis. The therapeutic effect of GHANPs on alveolar bone loss was explored in experimental periodontitis by histological staining and micro‐CT analysis. Results: A lower macrophage M2/M1 ratio was observed in periodontitis‐affected human gingival tissues. The results of animal experiments demonstrated a positive correlation between a lower Arg‐1/iNOS ratio and accelerated alveolar bone loss; also, the proportion of Arg‐1‐positive macrophages increased during bone repair and regeneration. The administration of GHANPs partially restored M2 macrophage polarization after LPS stimulation. GHANPs increased alveolar bone repair and regeneration in experimental periodontitis induced by ligation, potentially related to their macrophage M2 transition regulation. Conclusions: The findings of this study indicate that the induction of macrophage M2 polarization can be considered a viable approach for enhancing inflammatory bone repair. Additionally, GHANPs show potential in the clinical treatment of periodontitis. [ABSTRACT FROM AUTHOR]

Townes‐Brocks syndrome (TBS) is an autosomal dominant disorder characterised by the triad of anorectal, thumb, and ear malformations. It may also be accompanied by defects in kidney, heart, eyes, hearing, and feet. TBS has been demonstrated to result from heterozygous variants in the SALL1 gene, which encodes zinc finger protein believed to function as a transcriptional repressor. The clinical characteristics of an atypical TBS phenotype patient from a Chinese family are described, with predominant manifestations including external ear dysplasia, unilateral renal hypoplasia with mild renal dysfunction, and hearing impairment. A novel heterozygous variant c.3060T>A (p.Tyr1020*) in exon 2 of the SALL1 gene was identified in this proband. Pyrosequencing of the complementary DNA of the proband revealed that the variant transcript accounted for 48% of the total transcripts in peripheral leukocytes, indicating that this variant transcript has not undergone nonsense‐mediated mRNA decay. This variant c.3060T > A is located at the terminal end of exon 2, proximal to the 3′ end of the SALL1 gene, and exerts a relatively minor impact on protein function. We suggest that the atypical TBS phenotype observed in the proband may be attributed to the truncated protein retaining partial SALL1 function. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS), which are key cellular signalling molecules, are reactive chemicals containing oxygen. Cell survival or death is a critical issue in the inflammatory response. Accumulation of ROS involves ROS generation and scavenging, which determine ROS homeostasis. Understanding the roles of ROS in modulating the inflammatory response in fish is vital for helping protect fish from the damage of water pollutants in harsh environmental conditions. ROS‐related key genes and signalling pathways are relatively conserved in fish but vary among different species. Recent frequent incidences of fish diseases have posed a considerable challenge to large‐scale aquaculture. ROS is important in stress perception, integration of diverse stress‐responsive signalling networks, and activation of animal defence mechanisms, which frequently occur during inflammation in fish. This review summarises recent studies on ROS signalling pathways during inflammation in fish. Furthermore, it examines the relationship between ROS and inflammation in fish. This review may contribute to the understanding of the underlying mechanisms by which ROS regulate inflammation in fish and provide suggestions for sustainable development in aquaculture. [ABSTRACT FROM AUTHOR]

Following the latest Permian mass extinction (LPME), abundant unusual sedimentary features and fabrics were widely distributed in Early Triassic carbonate platforms. As a unique type of carbonate grain, spheroids from the Lower Triassic are infrequently reported, yet differ significantly from giant ooids and oncoids. Griesbachian micritic spheroids are well preserved in the Lower Triassic Feixianguan Formation at the Baimiaozi (BMZ) outcrop in Beibei, Chongqing, southwestern China. These spheroids (diameter: 3.9–10.8 mm) were in a marl layer interbedded with massive oolites. They were deposited in the wave troughs of ripple marks comprising micritic clots, sparry calcite, clay minerals, organic matter and pyrite. A microbial spheroid origin is implied based on the coccoidal microbes (coccoid‐like microspherules and bacterial clump‐like microspherules), numerous pyrite framboids (indications suggest the presence of many sulphate‐reducing bacteria and the high iron content in seawater can promote nitrogen‐fixing cyanobacteria proliferation) and microbial‐derived microspherules. The dark‐coloured matrix between the spheroids primarily included microcrystalline calcite, clay minerals, organic matter and metazoan fossils. The spherical and ellipsoidal shapes of the spheroids suggested rapid accretion and lithification. As a unique carbonate depositional mode, Greisbachian spheroids may have been recorded for a palaeo‐ocean with dysoxic and calcium carbonate supersaturation shortly after the LPME. [ABSTRACT FROM AUTHOR]

Cystinosis is a severe, monogenic systemic disease caused by variants in CTNS gene. Currently, there is growing evidence that exonic variants in many diseases can affect pre‐mRNA splicing. The impact of CTNS gene exonic variants on splicing regulation may be underestimated due to the lack of routine studies at the RNA level. Here, we analyzed 59 exonic variants in the CTNS gene using bioinformatics tools and identified candidate variants that may induce splicing alterations by minigene assays. We identified six exonic variants that induce splicing alterations by disrupting the ratio of exonic splicing enhancers/exonic splicing silencers (ESEs/ESSs) or by interfering with the recognition of classical splice sites, or both. Our results help in the correct molecular characterization of variants in cystinosis and inform emerging therapies. Furthermore, our work suggests that the combination of in silico and in vitro assays facilitates to assess the effects of DNA variants driving rare genetic diseases on splicing regulation and will enhance the clinical utility of variant functional annotation. [ABSTRACT FROM AUTHOR]

Background: X‐linked Alport syndrome (XLAS) is an inherited renal disease caused by rare variants of COL4A5 on chromosome Xq22. Many studies have indicated that single nucleotide variants (SNVs) in exons can disrupt normal splicing process of the pre‐mRNA by altering various splicing regulatory signals. The male patients with XLAS have a strong genotype–phenotype correlation. Confirming the effect of variants on splicing can help to predict kidney prognosis. This study aimed to investigate whether single nucleotide substitutions, located within three bases at the 5′ end of the exons or internal position of the exons in COL4A5 gene, cause aberrant splicing process. Methods: We analyzed 401 SNVs previously presumed missense and nonsense variants in COL4A5 gene by bioinformatics programs and identified candidate variants that may affect the splicing of pre‐mRNA via minigene assays. Results: Our study indicated three of eight candidate variants induced complete or partial exon skipping. Variants c.2678G>C and c.2918G>A probably disturb classic splice sites leading to corresponding exon skipping. Variant c.3700C>T may disrupt splicing enhancer motifs accompanying with generation of splicing silencer sequences resulting in the skipping of exon 41. Conclusion: Our study revealed that two missense variants positioned the first nucleotides of the 5′ end of COL4A5 exons and one internal exonic nonsense variant caused aberrant splicing. Importantly, this study emphasized the necessity of assessing the effects of SNVs at the mRNA level. [ABSTRACT FROM AUTHOR]

Attention deficit is a critical symptom that impairs social functioning in adolescents with major depressive disorder (MDD). In this study, we aimed to explore the dynamic neural network activity associated with attention deficits and its relationship with clinical outcomes in adolescents with MDD. We included 188 adolescents with MDD and 94 healthy controls. By combining psychophysics, resting‐state electroencephalography (EEG), and functional magnetic resonance imaging (fMRI) techniques, we aimed to identify dynamic network features through the investigation of EEG microstate characteristics and related temporal network features in adolescents with MDD. At baseline, microstate analysis revealed that the occurrence of Microstate C in the patient group was lower than that in healthy controls, whereas the duration and coverage of Microstate D increased in the MDD group. Mediation analysis revealed that the probability of transition from Microstate C to D mediated anhedonia and attention deficits in the MDD group. fMRI results showed that the temporal variability of the dorsal attention network (DAN) was significantly weaker in patients with MDD than in healthy controls. Importantly, the temporal variability of DAN mediated the relationship between anhedonia and attention deficits in the patient group. After acute‐stage treatment, the response prediction group (RP) showed improvement in Microstates C and D compared to the nonresponse prediction group (NRP). For resting‐state fMRI data, the temporal variability of DAN was significantly higher in the RP group than in the NRP group. Overall, this study enriches our understanding of the neural mechanisms underlying attention deficits in patients with MDD and provides novel clinical biomarkers. [ABSTRACT FROM AUTHOR]

Conductive fibers are vital for next‐generation wearable and implantable electronics. However, the mismatch of mechanical, electrical, and biological properties between existing conductive fibers and human tissues significantly retards their further development. Here, the concept of neuro‐like fibers to meet these aforementioned requirements is proposed. A new wet spinning process is established to continuously produce pure gelatin hydrogel fibers. The key is the controllable and rapid gelation of spinning solutions based on the salting‐out effect, which is inspired by the Chinese food tofu. The resultant fibers exhibit neuro‐like features of soft‐while‐strong mechanical properties, high ionic conductivity, and superior biological properties including biodegradability, biocompatibility, and edibility, which are crucial for implanted applications but seldom reported. Furthermore, all‐weather suitable neuro‐like fibers with excellent anti‐freezing and water retention properties are developed by introducing glycerol for wearable applications. The optical fiber, transient electronics, and electronic data glove made of neuro‐like fibers profoundly demonstrate their potential in biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Bone loss is a common complication of inflammatory bowel disease (IBD); however, few studies have focused on alveolar bone loss (ABL) in IBD. Herein, we systematically observed ABL in an interleukin (IL)-10 knockout (IL-10-/- ) mouse model of IBD and explored the possible mechanisms.Methods: IL-10-/- and age-matched wild-type (WT) male mice were sacrificed every 2 weeks from 12 to 24 weeks of age. ABL was determined by microcomputed tomography. Periodontal and intestinal inflammation were evaluated using histological grading and inflammatory factor expression levels. Intestinal barrier integrity and cytokine levels in serum were examined by immunofluorescence and enzyme-linked immunosorbent assays, respectively. The expression of macrophage phenotype markers, including inducible nitric oxide synthase (iNOS), arginase-1 (Arg-1), and bone metabolic markers, including osteoprotegerin, receptor activator of nuclear factor-κB ligand (RANKL), were measured by immunohistochemistry. The macrophage phenotype in the periodontium was also examined by real-time quantitative polymerase chain reaction.Results: Compared with WT mice, IL-10-/- mice exhibited significant ABL from 18 weeks of age. However, no significant differences were observed in the periodontium between the two groups in either histopathological scores or inflammatory factor levels. In the colon and ileum, these measurements significantly increased in IL-10-/- mice from 12 and 14 weeks, respectively. Correlation analysis also revealed that ABL in IL-10-/- mice was positively correlated with intestinal inflammation. Furthermore, IL-10-/- mice showed a destroyed intestinal barrier and higher serum levels of inflammatory factors. In both the intestine and periodontium, higher iNOS and lower Arg-1 levels, along with an increase in RANKL expression in the periodontium, were examined in IL-10-/- mice.Conclusions: An accelerated ABL spontaneously occurred in IL-10-/- mice and was correlated more with inflammation of the intestine than periodontium. Immunopathological changes may be the potential cause of abnormal alveolar bone metabolism. [ABSTRACT FROM AUTHOR]

The employment of the new Schiff base ligand 2‐[(4‐chloro‐2‐hydroxybenzylideneamino)methyl]phenol (H2L) bearing O2N donors for the preparation of a novel Co6 cluster is reported. The hexanuclear cobalt complex, namely, di‐μ2‐acetatotetrakis{μ2‐2‐[(4‐chloro‐2‐oxidobenzylideneamino)methyl]phenolato}tetra‐μ3‐methanolato‐tetracobalt(II)dicobalt(III), [CoII4CoIII2(C14H10ClNO2)4(CH3COO)2(CH3O)4], was obtained using Co(CH3COO)2·4H2O and H2L as starting materials in MeOH under solvothermal conditions. The six metal ions are linked together by the μ3‐O atoms of four deprotonated MeOH molecules, two CH3COO− units and six phenolate O atoms of four L2− ligands to form a defect disk‐shaped topology. DC magnetic susceptibility investigations revealed the existence of antiferromagnetic interactions in the Co6 cluster. [ABSTRACT FROM AUTHOR]

BACKGROUND The Xinjiang Uygur Autonomous Region is an arid and semi‐arid region with low rainfall and strong sunlight; thus, grape berries in this region accumulate sugar content rapidly, and the ripening process is shorter than that in other regions. Although previous studies illustrated that altered sunlight conditions could influence the aroma profiles of grape berries, less attention has been paid to the effect of vine top shading on volatile compounds under a dry–hot climate. RESULT: We focused on the effects of vine top shading on the concentrations of linolenic and linoleic acids, as well as their metabolites, the C6/C9 compounds, in grape berries. Four vine top shading treatments at veraison (ripening onset) and post‐veraison (skin full coloration) were performed by reducing solar exposure to the grapevines by 20% and 50% respectively. Apart from (E)‐2‐hexenal in the 20% shading treatment of 2016, (E)‐2‐hexenal were not promoted by the 50% shading and 20% shading treatments during veraison to harvest in both of the vintages. By contrast, the influence of vine top shading from post‐veraison till harvest was different between the two vintages; these C6 compounds were decreased in both of the shading treatments in 2016, whereas most of them were promoted in 2017, possibly related to daily sunshine hours in this period. In addition, the C9 compound nonanal with very low concentration exhibits a significant difference among various treatments by two‐factor analysis of variance. As for linolenic acid and linoleic acid, two types of C6 compound biosynthetic precursors, four shading treatments all reduced their concentration, except for linolenic acid in the 50% shading treatment of 2016. Moreover, it appeared to have no apparent correlation between the variations of two precursors and their volatile metabolites, indicating that there is a complex impact of vine shading on C6 compound biosynthesis. CONCLUSION: Vine top shading at veraison can reduce the accumulation of some C6 compounds in grape berries, but no consistent consequence was attained for the vine shading at pre‐veraison. The findings indicate the significance of grapevine solar exposure management at veraison in controlling the level of C6 compounds in a dry–hot region like Xinjiang. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Cell division is a central process in bacteria and a prerequisite for pathogenicity. Several proteins are involved in this process to ensure the accurate localization and proper function of the division machinery. In Streptococcus mutans, MapZ marks the division sites and position of the Z‐ring to regulate cell division; however, whether MapZ deficiency can impair the cariogenic virulence of S. mutans remains unclear. Here, using a phenotypic assay and RNA‐seq, we investigated the role of MapZ in cell envelope maintenance, biofilm formation, and stress tolerance in S. mutans. The results show that MapZ is important for normal cell shape and envelope structure, and its deletion causes abnormal septum structure and a thin cell wall. Subsequently, we found that the absence of MapZ leads to a greater level of cell death within 12 h biofilms, but it does not seem to affect biofilm architecture and accumulation. mapZ deletion also results in a decreased acid and osmotic stress tolerance. Furthermore, RNA‐seq data reveal that MapZ deficiency causes changes in the expression levels of genes involved in transport systems, sugar metabolism, nature competence, and bacteriocin synthesis. Interestingly, we found that mapZ mutation renders S. mutans more sensitive to chlorhexidine. Taken together, our study suggests that MapZ plays a role in maintaining cell envelope structure and stress tolerance in S. mutans, showing a potential application as a drug target for caries prevention. [ABSTRACT FROM AUTHOR]

Purpose: To determine the postoperative effects of radiotherapy (PORT) on the local recurrence‐free survival (LRFS) and overall survival (OS) of stage III‐N2 non‐small‐cell lung cancer (NSCLC). Materials and Methods: 183 patients with resected stage III‐pN2 NSCLC from Hunan Cancer Hospital between 2013 and 2016 were divided into two groups for postoperative chemotherapy (POCT) (n = 105) or combination chemotherapy and radiotherapy (POCRT) (n = 78). The LRFS and OS were compared and the factors affecting local recurrence were illustrated in these two groups. The sites of failure based on the lobe of the primary tumor in two groups were described. Results: PORT leads to a strikingly lower risk for local recurrence and brought superior OS benefit. For different pN2 Subclassification, Patients with multiple‐station pN2 ± pN1 disease had the worst LRFS (11 months) and single‐station pN2 + multiple station pN1 disease had a relatively short LRFS (24 months) in group POCT. Short LRFS is correlated with multiple‐station pN2, older age (Y > 55), patients with a high positive LN ratio > 1/3 and a poor tumor histological differentiation degree. In group POCT, the most frequent failure site occurs at the ipsilateral hilum (21.0%), the bronchial stump (20.0%), followed by LNs4R (19.0%), LNs4L (18.1%), LNs7 (15.2%), most of left‐sided tumors more frequently involved the contralateral mediastinum, whereas the ipsilateral recurrences dominated for right‐sided tumors, especially for LNs4R. In group POCRT, the highest failure site was the bronchial stump (11.5%), followed by LNs4L (8.97%), LNs1 (7.69%), the ipsilateral hilum (6.41%) and LNs4R (6.41%). Conclusion: PORT remarkably reduced local recurrence and improved OS in stage III‐pN2 NSCLC, especially in the multiple‐station pN2 group. [ABSTRACT FROM AUTHOR]

An ICT‐based mitochondria‐targeted fluorescent probe Mito‐NP was designed and synthesized for the detection of H2O2, with radical fluorescence intensity changes (up to 120‐fold) and a large Stokes shift (93 nm) in aqueous solution. There was good linear relationship (R2=0.9983) between the concentration of H2O2 in the range of 0 to 100 μM and the fluorescence intensity at 553 nm, with a low detection limit of 0.25 μM (S/N=3). Mito‐NP could also visualize enzymatically generated H2O2. Furthermore, the probe could detect endogenous H2O2 with good mitochondria targeting ability in living cells and could also detect the change in H2O2 levels during mitochondria‐oriented apoptosis. Introduction An ICT‐based mitochondria‐targeted fluorescent probe was designed and synthesized for hydrogen peroxide with a large turn‐on fluorescence signal in water and its bo‐imaging in living cells and it could also detect the change in H2O2 levels during mitochondria‐oriented apoptosis. [ABSTRACT FROM AUTHOR]

This article examines whether relationships between social capital characteristics and the willingness of farmers to cooperate in collective action is moderated by the farmers' income level. We employed a structural equation model to analyze the influence of social capital components (social networks, interpersonal trust, social reciprocity, and social participation) on the willingness of farmers to cooperate in collective small‐scale irrigation in Guangling County, Shanxi Province of China. This analysis was complemented by a multigroup analysis to measure the potential variance effects across income groups. Our results show that low‐ and middle‐income farmers give more importance to the aspects of social networks, social reciprocity, and social participation, while high‐income farmers place emphasis on interpersonal trust and social participation. Accordingly, the willingness of farmers to cooperate for the different income groups was influenced in different ways in relation to the various social capital components. Therefore, social capital and income differences have complex effects on the willingness of farmers to cooperate. In this regard, our research provides an alternative way to understand the complex process involved in the formation of collective action under the presence of increasing economic heterogeneity in local communities. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Food‐grade bacterial expression systems are relatively rare, and increasing evidence indicates that subcellular location of antigens in bacterial vector vaccines may markedly affect the immune efficacy. RESULTS: This study developed a novel food‐grade secretory expression system for heterologous protein production and oral vaccine delivery. Furthermore, by using the expression system, an engineered L. lactis strain secreting H. pylori UreB was constructed, and used to vaccinate SPF BALB/c mice. As results, the UreB expressed in L. lactis was detected in both cell lysates and culture supernatant of the engineered strain, constituting roughly 50% of the culture supernatant proteins, and recognized by mouse anti‐H. pylori sera. Oral vaccination with the engineered L. lactis produced a significantly elevated anti‐UreB serum antibody level in mice (P < 0.05). CONCLUSION: These data show a novel food‐grade L. lactis secretory expression system, which may have distinct potential impact on edible and medicinal protein production and oral vaccine development. Moreover, this is the first report on secretory expression of a H. pylori antigen via using a food‐grade lactococcal expression system, and the engineered strain secreting UreB can be a hopeful H. pylori vaccine candidate. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A dual-mechanism intramolecular charge transfer (ICT)-FRET fluorescent probe for the selective detection of H2O2 in living cells has been designed and synthesized. This probe used a coumarin-naphthalimide hybrid as the FRET platform and a boronate moiety as the recognition group. Upon the addition of H2O2, the probe exhibited a redshifted (73 nm) fluorescence emission, and the ratio of fluorescence intensities at λ=558 and 485 nm ( F558/ F485) shifted notably (up to 100-fold). Moreover, there was a good linearity ( R2=0.9911) between the ratio and concentration of H2O2 in the range of 0 to 60 μ m, with a limit of detection of 0.28 μ m (signal to noise ratio (S/N)=3). This probe could also detect enzymatically generated H2O2. Importantly, it could be used to visualize endogenous H2O2 produced by stimulation from epidermal growth factor. [ABSTRACT FROM AUTHOR]

ABSTRACT Four novel benzimidazolyl phosphates (BPs) were synthesized and evaluated as anti-wear additives in poly(ethylene glycol) for steel/steel contacts. The friction experiments were carried out on an Optimol SRV-I oscillating reciprocating friction and wear tester (SRV) both at room temperature and high temperature. The worn surfaces of the steel discs were analysed by JSM-5600LV scanning electron microscope and PHI-5702 multifunctional X-ray photoelectron spectrometer. It was indicated that poly(ethylene glycol) with 2 wt% BP additives had better friction-reducing and anti-wear properties than the commercial lubricant additive, tricresyl phosphate. Excellent tribological performance of BPs could be ascribed to the formation of high quality boundary films that consisted of the ordered adsorption films and tribo-chemical reaction films. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hepatic stem cell niche plays an important role in hepatic oval cell-mediated liver regeneration. As a component of hepatic stem cell niche, the role of hepatic stellate cells (HSCs) in oval cell proliferation needs further studies. In the present study, we isolated HSCs from rats at indicated time point after partial hepatectomy (PH) in 2-acetylaminofluorene/PH oval cell proliferation model. Conditional medium (CM) from HSCs were collected to detect their effects on proliferation and the mitogen-activated protein kinase pathway activation of two oval cell lines. We found that CM collected from HSCs at early phase of liver regeneration (4 and 9 days group) contained high levels of hepatocyte growth factor (HGF) and stimulated oval cell proliferation via extracellular signal-regulated kinase and p38 pathway. CM collected from HSCs at terminal phase of liver regeneration (12 and 15 days group) contained high levels of transforming growth factor (TGF)-β1, which suppressed DNA synthesis of oval cells. The shift between these two distinct effects depended on the balance between HGF and TGF-β1 secreted by HSCs. Our study demonstrated that HSCs acted as a positive regulator at the early phase and a negative regulator at the terminal phase of the oval cell-mediated liver regeneration. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

B-cell biology has been largely uncharacterized in the field of tuberculosis (TB). In this study, we investigated the immunophenotypical and functional characteristics of B cells obtained from the pleural fluid (PF) and peripheral blood of patients with tuberculous pleuritis (TP). Our results indicated that the total numbers of B cells, CD27+ memory B cells and plasmablasts were clearly lower in the PF than in peripheral blood. Furthermore, we found significantly higher expression of CXCR4 on B cells in the PF, and a chemotaxis assay showed that B cells in the PF were more responsive to stromal cell-derived factor-1 (SDF-1) than B cells from peripheral blood. In addition, SDF-1 levels in PF were remarkably high compared with SDF-1 levels in plasma, suggesting that the SDF-1/CXCR4 axis might facilitate the migration of circulating B cells into tuberculous pleural space. Importantly, we observed that significantly more antibodies were produced by B cells in the PF following stimulation with BCG, early secretory antigenic target (ESAT-6)/culture filtrate protein-10 (CFP-10) or ESAT-6 protein. Collectively, these data demonstrate that Mycobacterium tuberculosis-specific B cells exist at local sites of infection in TP patients and this localization might influence the immune response to M. tuberculosis. [ABSTRACT FROM AUTHOR]

Summary Natural killer (NK) cells are known as innate immune lymphocytes that respond rapidly when challenged by pathogens but little is known about adaptive immune features including memory related to NK cells from human beings. In the present study, we demonstrate for the first time that human NK cells expressing the memory-associated marker CD45RO were persistent in pleural fluid cells (PFCs) from tuberculous patients. CD45RO+ NK cells produced significantly more interferon-γ and were more cytotoxic compared with CD45RO− NK cells from PFCs when stimulated with interleukin-12 (IL-12). Consistently, IL-12 enhanced the expression of granzyme B, CD69, CD25, NKG2D, IL-12 receptors β1 and β2 on CD45RO+ NK cells from PFCs. Our experiments contribute to a better understanding of the NK cells from PFCs and indicate that human CD45RO+ NK cells from PFCs expressing a 'memory-like' phenotype may have an important role in defending against infection by Mycobacterium tuberculosis. [ABSTRACT FROM AUTHOR]