Identification of mitophagy-related biomarkers in osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is a common joint disease, and existing drugs cannot cure OA, so there is an urgent need to identify new targets. Mitophagy plays an important role in OA; however, the role of mitophagy in the OA immune system is not yet clear. METHODS: In this study, differential analysis and enrichment analysis were used to identify mitophagy-related genes (MRGs) with differential expression in OA and the functional pathways involved in OA. Subsequently, two machine learning methods, RF and LASSO, were used to screen MRGs with diagnostic value and construct nomograms. At the same time, the relationship between mitophagy and OA immune response was explored by immunoinfiltration analysis. RESULTS: Forty-three differentially MRGs were identified in OA, of which six MRGs (GABARAPL2, PARL, GABARAPL1, JUN, RRAS, and SNX7) were associated with the diagnosis of OA. The ROC analysis results show that these 6 MRGs have high predictive accuracy in the diagnosis of OA. In immune infiltration analysis, we found that the abundance of significantly different immune cells in OA was mostly upregulated. In addition, the expression of diagnostic-related MRGs is correlated with changes in the abundance of immune cells in OA. CONCLUSION: This study demonstrates that six MRGs can be used as diagnostic biomarkers. The expression of diagnostic-related MRGs is correlated with changes in the abundance of immune cells in OA. At the same time, mitophagy may affect the immune microenvironment of OA by regulating immune cells, ultimately leading to the progression of OA.

Differentiation of closely-related species within Acinetobacter baumannii-calcoaceticus complex via Raman spectroscopy: a comparative machine learning analysis.

Bacterial species within the Acinetobacter baumannii-calcoaceticus (Acb) complex are very similar and are difficult to discriminate. Misidentification of these species in human infection may lead to severe consequences in clinical settings. Therefore, it is important to accurately discriminate these pathogens within the Acb complex. Raman spectroscopy is a simple method that has been widely studied for bacterial identification with high similarities. In this study, we combined surfaced-enhanced Raman spectroscopy (SERS) with a set of machine learning algorithms for identifying species within the Acb complex. According to the results, the support vector machine (SVM) model achieved the best prediction accuracy at 98.33% with a fivefold cross-validation rate of 96.73%. Taken together, this study confirms that the SERS-SVM method provides a convenient way to discriminate between A. baumannii, Acinetobacter pittii, and Acinetobacter nosocomialis in the Acb complex, which shows an application potential for species identification of Acinetobacter baumannii-calcoaceticus complex in clinical settings in near future.

Architecture engineering of Fe/Fe2O3@MoS2 enables highly efficient tetracycline remediation via peroxymonosulfate activation: Critical roles of adsorption capacity and redox cycle regulation.

Design and synthesis of high-efficiency multicomponent nanostructure for activating peroxymonosulfate (PMS) to destruct emerging antibiotics remains a daunting challenge. We report herein the simplest one-step hydrothermal construction of hierarchical Fe/Fe2O3@MoS2 architecture composed of MoS2 nanosheets integrated commercial Fe2O3 nanoparticles. The fabricated Fe/Fe2O3@MoS2 architecture can be utilized as an efficient PMS activator to destruct tetracycline hydrochloride (TCH) with a removal efficiency of 90.3 % within 40 min, outperforming Fe2O3 nanoparticles, MoS2 nanosheets analogues and many MoS2-based materials. The Fe/Fe2O3@MoS2/PMS works well under various reaction conditions, and SO4•- and 1O2 are identified as major reactive oxygen species. Thirteen intermediates towards TCH destruction are detected via four pathways, and their acute/chronic toxicity and phytotoxicity are assessed. The origins of Fe/Fe2O3@MoS2/PMS system for efficient degrading TCH are ascribed to the synergy catalysis between Fe2O3 and MoS2, which originate from: (a) the exposed Mo4+ sites on catalyst surface facilitating high-speed electron transfer from MoS2 to Fe3+ and accelerating the Fe2+ regeneration; (b) the generated Fe0 serving as an excellent electron donor to jointly promote Fe3+/Fe2+ redox cycle. This study provides a simple way to establish architecture for synergistically promoting PMS-mediated degradation.

Classification and prediction of Klebsiella pneumoniae strains with different MLST allelic profiles via SERS spectral analysis.

The Gram-negative non-motile Klebsiella pneuomoniae is currently a major cause of hospital-acquired (HA) and community-acquired (CA) infections, leading to great public health concern globally, while rapid identification and accurate tracing of the pathogenic bacterium is essential in facilitating monitoring and controlling of K. pneumoniae outbreak and dissemination. Multi-locus sequence typing (MLST) is a commonly used typing approach with low cost that is able to distinguish bacterial isolates based on the allelic profiles of several housekeeping genes, despite low resolution and labor intensity of the method. Core-genome MLST scheme (cgMLST) is recently proposed to sub-type and monitor outbreaks of bacterial strains with high resolution and reliability, which uses hundreds or thousands of genes conserved in all or most members of the species. However, the method is complex and requires whole genome sequencing of bacterial strains with high costs. Therefore, it is urgently needed to develop novel methods with high resolution and low cost for bacterial typing. Surface enhanced Raman spectroscopy (SERS) is a rapid, sensitive and cheap method for bacterial identification. Previous studies confirmed that classification and prediction of bacterial strains via SERS spectral analysis correlated well with MLST typing results. However, there is currently no similar comparative analysis in K. pneumoniae strains. In this pilot study, 16 K. pneumoniae strains with different sequencing typings (STs) were selected and a phylogenetic tree was constructed based on core genome analysis. SERS spectra (N = 45/each strain) were generated for all the K. pneumoniae strains, which were then comparatively classified and predicted via six representative machine learning (ML) algorithms. According to the results, SERS technique coupled with the ML algorithm support vector machine (SVM) could achieve the highest accuracy (5-Fold Cross Validation = 100%) in terms of differentiating and predicting all the K. pneumoniae strains that were consistent to corresponding MLSTs. In sum, we show in this pilot study that the SERS-SVM based method is able to accurately predict K. pneumoniae MLST types, which has the application potential in clinical settings for tracing dissemination and controlling outbreak of K. pneumoniae in hospitals and communities with low costs and high rapidity.

Abrogation of MAP4K4 protein function causes congenital anomalies in humans and zebrafish.

We report 21 families displaying neurodevelopmental differences and multiple congenital anomalies while bearing a series of rare variants in mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4). MAP4K4 has been implicated in many signaling pathways including c-Jun N-terminal and RAS kinases and is currently under investigation as a druggable target for multiple disorders. Using several zebrafish models, we demonstrate that these human variants are either loss-of-function or dominant-negative alleles and show that decreasing Map4k4 activity causes developmental defects. Furthermore, MAP4K4 can restrain hyperactive RAS signaling in early embryonic stages. Together, our data demonstrate that MAP4K4 negatively regulates RAS signaling in the early embryo and that variants identified in affected humans abrogate its function, establishing MAP4K4 as a causal locus for individuals with syndromic neurodevelopmental differences.

Rapid discrimination of Shigella spp. and Escherichia coli via label-free surface enhanced Raman spectroscopy coupled with machine learning algorithms.

Shigella and enterotoxigenic Escherichia coli (ETEC) are major bacterial pathogens of diarrheal disease that is the second leading cause of childhood mortality globally. Currently, it is well known that Shigella spp., and E. coli are very closely related with many common characteristics. Evolutionarily speaking, Shigella spp., are positioned within the phylogenetic tree of E. coli. Therefore, discrimination of Shigella spp., from E. coli is very difficult. Many methods have been developed with the aim of differentiating the two species, which include but not limited to biochemical tests, nucleic acids amplification, and mass spectrometry, etc. However, these methods suffer from high false positive rates and complicated operation procedures, which requires the development of novel methods for accurate and rapid identification of Shigella spp., and E. coli. As a low-cost and non-invasive method, surface enhanced Raman spectroscopy (SERS) is currently under intensive study for its diagnostic potential in bacterial pathogens, which is worthy of further investigation for its application in bacterial discrimination. In this study, we focused on clinically isolated E. coli strains and Shigella species (spp.), that is, S. dysenteriae, S. boydii, S. flexneri, and S. sonnei, based on which SERS spectra were generated and characteristic peaks for Shigella spp., and E. coli were identified, revealing unique molecular components in the two bacterial groups. Further comparative analysis of machine learning algorithms showed that, the Convolutional Neural Network (CNN) achieved the best performance and robustness in bacterial discrimination capacity when compared with Random Forest (RF) and Support Vector Machine (SVM) algorithms. Taken together, this study confirmed that SERS paired with machine learning could achieve high accuracy in discriminating Shigella spp., from E. coli, which facilitated its application potential for diarrheal prevention and control in clinical settings. Graphical abstract.

Clinical significance of flow cytometry in detection of minimal residual disease in cerebrospinal fluid. / è„‘è„Šæ¶²æµå¼ç»†èƒžæœ¯æ£€æµ‹å¾®å°æ®‹ç•™ç— çš„ä¸´åºŠæ„ä¹‰.

OBJECTIVES: Central nervous system leukemia (CNSL) is one of the main causes of recurrence and death in patients with acute leukemia. This study aims to dynamically monitor minimal residual disease (MRD) in cerebrospinal fluid and bone marrow of patients with different types of acute leukemia by flow cytometry (FCM), and to compare the timeliness and consistency of MRD detection between the 2 methods to further explore the application value of monitoring MRD in cerebrospinal fluid. METHODS: A total of 199 patients with acute leukemia admitted to the Guangdong Provincial people's Hospital between October 2018 and January 2022 were retrospectively analyzed, and multiparametric FCM method was adopted to summarize and analyze MRD in cerebrospinal fluid of patients with different types of leukemia and MRD in cerebrospinal fluid and bone marrow specimens of the same patients, and its role in assessing the prognostic value of patients was discussed. RESULTS: Among the 199 acute leukemia cases, a total of 31 cases (15.58%) were positive MRD in the cerebrospinal fluid, of which 18 cases (58%) were detected earlier than the corresponding bone marrow specimens. Among the 19 patients with acute T lymphoblastic leukemia, 134 patients with acute B lymphoblastic leukemia, and 46 patients with acute myeloid leukemia counted, there were 4, 18, and 9 patients with positive MRD in the cerebrospinal fluid. The Kappa value of the concordance test between the results of cerebrospinal fluid MRD and bone marrow MRD in different types of acute leukemia was only 0.156, demonstrating a low concordance between them. CONCLUSIONS: Dynamic monitoring of cerebrospinal fluid MRD by FCM can be used as a monitoring index for central nervous system leukemia, and monitoring cerebrospinal fluid can detect MRD earlier compared with bone marrow, which complements each other as a sensitive index for evaluating prognosis with significant guidance in clinic.

Prevalence of diabetes mellitus among Uygur children in Hotan Prefecture of Xinjiang, China. / æ–°ç–†å’Œç”°åœ°åŒºç»´å¾å°”æ—å„¿ç«¥ç³–å°¿ç— æ‚£ç— çŽ‡è°ƒæŸ¥.

OBJECTIVES: To investigate the prevalence of diabetes mellitus (DM) among Uygur children in Hotan Prefecture of Xinjiang, China, as well as the factors influencing the development of DM. METHODS: The cluster random sampling method was used to select 5 308 children, aged 4-18 years, from the middle and primary schools and kindergartens in Hotan Prefecture of Xinjiang. The survey methods included questionnaire survey and the measurement of height and weight. All subjects were tested for fasting fingertip blood glucose to investigate the prevalence of DM and impaired fasting glucose (IFG). RESULTS: A total of 5 184 valid questionnaires were collected. Fourteen children (0.27%) were found to have DM, among whom 8 had type 1 DM, 2 had type 2 DM, and 4 had unclassified DM. Twenty-nine children (0.56%) were found to have IFG. There was no significant difference in the prevalence rate of DM and IFG between boys and girls (P>0.05). The prevalence rate of DM was 0.18% in the 4-<10 years group, 0.47% in the 10-<15 years group, and 0.07% in the 15-18 years group (P=0.072).The prevalence rate of IFG in the above three age groups was 0.18%, 0.94%, and 0.42%, respectively, with a significant difference among groups (P=0.007). The proportion of family history of DM and the proportion of overweight/obesity in children with DM were significantly higher than those in children without DM (P<0.05), while the proportion of children with DM who preferred coarse grains was significantly lower than that in children without DM (P<0.05). CONCLUSIONS: The prevalence of DM and IFG in Uyghur children in Hotan Prefecture of Xinjiang is relatively low. There is no significant difference in the prevalence of DM among children of different genders or age groups, but the prevalence of IFG in children of different age groups is different. A family history of DM, overweight or obesity, and low intake of coarse grains might be associated with the development of DM.

Treatment of striae albae with 1,550 nm Er: Glass vs. CO2 fractional laser: A self-controlled study.

Objective: The objective of this study was to compare the efficacy and safety of fractional CO2 laser and 1,550 nm Er: glass laser in the treatment for the patients with striae albae. Methods: The female adults with striae albae in the abdomen for at least 12 months were recruited. After informed consent obtained, the patient received three treatments at 2-month intervals. The lesions on the left abdomen were treated with 10,600 nm CO2 fractional laser and right side treated with 1,550 nm Er: glass fractional laser. The pictures were taken before each visit and 3 months after the final treatment. The criteria for the evaluations using a quartile grading scale were excellent (76-100%), good (51-75%), fair (26-50%), poor (1-25%), and no improvement (0%). The safety and efficacy of the two lasers were independently evaluated using before and after photographs by two dermatologists. In addition, the self-reports to investigate the pain and satisfaction from patients were also recorded. Results: Totally, 27 cases were recruited, and 25 patients completed the treatments and follow-up. The excellent and good results (improvement of 51-100%) were achieved on the right abdomen in 84% of the patients, while 48% on the left site (p < 0.05). Hyper-pigmentation was seen in 20% of the patients assessed on the left abdomen and only in 8% on the right abdomen. During the treatments, average score of the pain on the right abdomen was 5.41 ± 2.13, which was higher than that on the left (4.19 ± 2.12) (p < 0.001). No permanent hyper-pigmentation was found on the both sides. Considering the whole treatments, the patients favored the modality used on the right side (80 vs. 68%, p < 0.05). Conclusion: Compared with CO2 fractional laser, 1,550 nm Er: glass fractional laser therapy provides the significantly better clinical outcomes and fewer side effects in the treatment of striae albae. Limitations: The sample size and follow-up time were limited.

High-level stable expression of gene for preparation of chlorothalonil hydrolytic dehalogenase and its application in elimination of chlorothalonil inhibition on bioconversion of lignocellulosic biomass.

To achieve the high-level stable expression of chlorothalonil hydrolytic dehalogenase (Chd), the gene chd was first integrated into the chromosome of Bacillus subtilis WB800. High generation stability was achieved by almost no gene lost after six generations but Chd activity decreased. aprE promoter alteration, translation initiation region modification and multi-copy chromosome integration were studied and these modifications could increase Chd activity by 270%, 2304% and 25%. Chlorothalonil residual exhibited inhibition on bioconversion of lignocellulosic biomass. The addition of Chd crude enzyme (60 µL per g wheat straw) could increase glucose production by 36.10% and 39.65% in synergistic hydrolysis and separate hydrolysis by laccase and cellulase with 120 mg/L residual chlorothalonil. Filter paper activity and carboxymethyl cellulase activity were enhanced by 12.84% and 23.95%, and biomass of Trichoderma reesei was increased by 76.67% under 50 µg chlorothalonil/g dry straw in solid-state fermentation. Thus, the high-level stable expressed Chd effectively eliminated chlorothalonil inhibition on enzymatic hydrolysis and solid-state fermentation. It showed promising potential for bioremediation of chlorothalonil pollution and improving conversion efficiency of lignocellulose.

Paclitaxel induces apoptosis through the TAK1-JNK activation pathway.

Paclitaxel (PTX) has previously been used to treat tumours of various tissue origins, such as lung, breast, ovarian, prostate cancers and leukemia. PTX-induced apoptosis is associated with p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), nuclear factor-kappa B (NF-κB) and c-Jun N-terminal kinase or stress-activated protein kinase (JNK/ SAPK) pathways. Transforming growth factor-beta-activated kinase 1 (TAK1) and TAK1-binding protein 1 (TAB1) play an important role in cell apoptosis through the p38, ERK, NF-κB and JNK signal transduction pathways. To investigate the role of TAK1 in PTX-induced cell apoptosis, we treated HEK293 and 8305C cells with 0-20 µM PTX for 6, 12 or 24 h. To investigate whether TAK1 can cooperate with PTX for cancer treatment, we transfected cells with TAK1, TAB1 or control plasmid and treated them with PTX (3-10 µM) for 9-24 h. Apoptosis rates were analysed by flow cytometry (Annexin V/PI). Endogenous TAK1 and TAB1, caspase-7 cleavage, poly ADP-ribose polymerase (PARP) cleavage, Bcl-xL level, phospho-p44/42, phospho-JNK and phospho-p38 were detected by western blot. We show that in HEK293 and 8305C cells, PTX enhanced the endogenous TAK1/TAB1 level and induced cell apoptosis in a dose- and time-dependent manner. Upon TAK1 overexpression in HEK293 cells treated with PTX, apoptosis rate, JNK phosphorylation and PARP cleavage increased contrary to heat-shocked or untreated cells. CRISPR editing of the tak1 gene upon PTX treatment resulted in lower phospho-JNK and PARP cleavage levels than in cells transfected with the control or the TAK1- or TAB1 + TAK1-containing plasmids. TAK1-K63A could not induce JNK phosphorylation or PARP cleavage. We conclude that PTX induces HEK293 and 8305C cell apoptosis through the TAK1-JNK activation pathway, potentially highlighting TAK1's role in chemosensitivity.

Novel Compound Heterozygous Variants in the LHCGR Gene in a Genetically Male Patient with Female External Genitalia

The LHCGR gene encodes a G-protein coupled receptor that plays a pivotal role in sexual differentiation in males, ovarian development in females and in fertility via its interaction with luteinizing hormone and chorionic gonadotropin. Inactive variants of the LHCGR gene cause Leydig cell hypoplasia (LCH), which is a rare disease and one of the causes of disorder of sexual differentiation (DSD) in males. The aim of this work was to clarify the clinical and molecular characteristics of a 2.75 year old patient with type 1 LCH. Whole exome sequencing was performed for the patient family and variants in the LHCGR gene were validated by Sanger sequencing. Pathogenicity of the missense variant was evaluated by multiple in silico tools. Our Chinese patient, who exhibited DSD, had female external genitalia (normal labia majora and minora, external opening of urethra under the clitoris and blind-ended vagina) and bilateral testis tissues in the inguinal region. Genetic sequencing revealed compound heterozygous variants in the LHCGR gene in the patient, including a novel missense variant in exon 4 (c.349G>A, p.Gly117Arg) and a novel nonsense variant in exon 10 (c.878C>A, p.Ser293*). The missense variant is in the first leucine-rich repeat domain of the LHCGR protein, which is predicted to affect ligand recognition and binding affinity and thus protein function. The patient is molecularly and clinically diagnosed with type 1 LCH, which is caused by novel, compound heterozygous variants of the LHCGR gene. We believe this report will serve to expand the genotypic spectrum of LHCGR variants.

Susceptibility-weighted imaging predicts infarct size and early-stage clinical prognosis in acute ischemic stroke.

Susceptibility-weighted imaging (SWI) is a non-invasive technique that can reveal venous structures and iron in the brain. This retrospective study evaluated SWI, relative to other imaging techniques, for determining cerebral infarct size and early-stage clinical prognosis in patients with acute ischemic stroke. Within 3 days after onset, 22 patients with acute ischemic stroke underwent SWI, diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI), fluid-attenuated inversion recovery (FLAIR), and magnetic resonance angiography (MRA). At least 7 days after onset, the patients also underwent cranial FLAIR or computed tomography (CT). The severity of neurological damage was adjudged with NIHSS (National Institutes of Health Stroke Scale) scores. The imaged cranial lesions were evaluated according to ASPECTS (Alberta Stroke Program Early CT Score). The SWI-ASPECTS significantly correlated with mean transit time (MTT)-ASPECTS (Spearman's test, r = 0.662, P = 0.001) in evaluating ischemic penumbra and significantly correlated with the FLAIR and CT-ASPECTS (Spearman's test, r = 0.765, P < 0.001) in predicting infarct size. SWI is feasible for the early evaluation of cerebral infarct size and clinical prognosis of patients with acute cerebral infarction. SWI is a useful predictor of early infarct growth and early-stage outcome.

Production of chlorothalonil hydrolytic dehalogenase from agro-industrial wastewater and its application in raw food cleaning.

BACKGROUND: To reduce the fermentation cost for industrialization of chlorothalonil hydrolytic dehalogenase (Chd), agro-industrial wastewaters including molasses, corn steep liquor (CSL) and fermentation wastewater were used to substitute for expensive carbon and nitrogen sources and fresh water for lab preparation. RESULTS: The results showed that molasses and CSL could replace 5% carbon source and 100% organic nitrogen source respectively to maintain the same fermentation level. Re-fermentation from raffinate of ultra-filtered fermentation wastewater could achieve 61.03% of initial Chd activity and reach 96.39% activity when cultured in a mixture of raffinate and 50% of original medium constituent. Typical raw foods were chosen to evaluate the chlorothalonil removal ability of Chd. After Chd treatment for 2 h at room temperature, 97.40 and 75.55% of 30 mg kg-1 chlorothalonil on cherry tomato and strawberry respectively and 60.29% of 50 mg kg-1 chlorothalonil on Chinese cabbage were removed. Furthermore, the residual activity of the enzyme remained at 78-82% after treatment, suggesting its potential for reuse. CONCLUSION: This study proved the cost-feasibility of large-scale production of Chd from agro-industrial wastewater and demonstrated the potential of Chd in raw food cleaning. © 2016 Society of Chemical Industry.

[Genotypes and phenotypes in Uygur children with 21-hydroxylase deficiency in Xinjiang, China].

OBJECTIVE: To investigate gene mutations and the relationship between genotypes and clinical phenotypes in Uygur children with 21-hydroxylase deficiency (21-OHD) in Xinjiang, China. METHODS: A total of 20 Uygur children with 21-OHD who visited the hospital between October 2013 and October 2014 were enrolled. Full-length direct sequencing and multiplex ligation-dependent probe amplification (MLPA) were used to detect the mutations of CYP21A2 gene, which encoded 21-hydroxylase. According to the type of mutation, the patients with 21-OHD were divided into different groups to analyze the consistency between predicted clinical phenotypes and actual clinical phenotypes. RESULTS: A total of 9 mutation types were found in the 20 patients, and 8 of them were identified as pathogenic mutations, i.e., Del, conv, I2g, I172N, Cluster E6, 8-bp del, V281L, and R356W. The other mutation is the new mutation occurring in intron 5 (c.648+37A>G), which had not been reported, and its pathological significance remains unknown. Most clinical phenotypes predicted by mutation types had a higher coincidence rate with actual clinical phenotypes (above 67%), and the clinical phenotypes predicted by P30L and V281L had a lower coincidence rate with actual clinical phenotypes (below 33%). CONCLUSIONS: The genotype of 21-OHD has a good correlation with phenotype, and the clinical phenotype can be predicted by detecting the patient′s genotype. The new mutation (c.648+37A>G) may be related to the pathogenesis of 21-OHD.

Extruded Soluplus/SIM as an oral delivery system: characterization, interactions, in vitro and in vivo evaluations.

The aim of this study was to obtain a stable, amorphous solid dispersion (SD) with Soluplus, prepared by hot-melt extrusion (HME) as an effective and stable oral delivery system to improve the physical stability and bioavailability of the poorly water-soluble simvastatin (SIM), a drug with relatively low Tg. The drug was proved to be miscible with Soluplus by calculation and measurements. The solubility, dissolution, thermal characteristics, interactions and physical stability of the SIM/Soluplus SDs were investigated. The crystal state of simvastatin in the SD was found to change from crystalline to amorphous form during the HME process and also hydrogen bonds were observed between SIM and the extruded Soluplus. The phase solubility showed the solubilization effect of Soluplus was strong and spontaneous. The equilibrium solubility illustrated that Soluplus/SIM SDs gained much higher solubility than its corresponding physical mixtures (PMs). Both of the dissolution profiles and in-vivo performance showed that the SIM/Soluplus SD obtained a marked enhancement, compared with the PM. There was a little change in the SIM/Soluplus SD during a 3-month storage period (40 °C, 75%), indicating the good physicochemical stability. The extruded Soluplus system prepared by HME is a good alternative for the water-insoluble SIM to improve the stability and bioavailability.

Erratum to: The effect of aging on the frequency, phenotype and cytokine production of human blood CD4 + CXCR5 + T follicular helper cells: comparison of aged and young subjects.

[This corrects the article DOI: 10.1186/1742-4933-11-12.].

The effect of aging on the frequency, phenotype and cytokine production of human blood CD4 + CXCR5 + T follicular helper cells: comparison of aged and young subjects.

BACKGROUND: T cell-dependent B-cell responses decline with age, indicating declined cognate helper activity of aged CD4 + T cells for B cells. However, the mechanisms remain unclear. T follicular helper (Tfh) cells, a novel T helper subset, play an essential role in helping B cells differentiation into long-lived plasma cells in germinal center (GC) or short-lived plasma cells. In the present study, we proposed that there might existe changes of proportion, phenotype or cytokine production of blood Tfh cells in healthy elderly individuals compared with healthy young individuals. RESULTS: The results showed that frequencies of aged blood CXCR5 + CD4 + Tfh cells increased compared with young subjects. Both aged and young blood CXCR5 + CD4 + Tfh cells constitutively expressed CD45RO, CCR7 and CD28, and few of these cells expressed CD69 or HLA-DR, which indicated that they were resting memory cells. There was no significant difference of IL-21 frequency production by aged blood CXCR5 + CD4 + Tfh determined by FACS compared with young individuals, however, aged PBMCs produced significantly higher levels of IL-21 evaluated by ELISA. Furthermore, there were no significant differences of percentages of IFN-γ, IL-4, IL-17 or IL-22 production by aged Tfh cells compared with their counterparts of young individuals respectively. However, frequencies of IL-17+ cells within aged CD4 + CXCR5-T cells were markedly lower than in the young individuals. Furthermore we observed different frequencies of IFN-γ, IL-17, IL-4 or IL-22 production by Tfh or by CD4 + CXCR5- cells in aged and young subjects respectively. CONCLUSIONS: Our data demonstrated that the frequencies of blood memory CXCR5 + CD4 + Tfh cells increased in the elderly population. There were similar frequencies of Th characterized cytokine production such as IL-21, IFN-γ, IL-4, IL-17 or IL-22 in aged and young Tfh cells. However, aged PBMCs produced a significantly higher amount of IL-21 compare to young subjects.

[Feasibility of monitoring clopidogrel resistance with flow cytometric analysis of platelet vasodilator stimulated phosphoprotein phosphorylation].

OBJECTIVE: To evaluate the feasibility of monitoring clopidogrel resistance with flow cytometric analysis of platelet vasodilator stimulated phosphoprotein (VASP) phosphorylation. METHODS: Twenty patients with coronary heart disease (CHD) and 17 healthy volunteers were examined for platelet aggregation rate and phosphorylation of VASP (calculated as platelet reactivity index, PRI) using traditional optical nephelometry and flow cytometry before and after concurrent therapy of clopidogrel and aspirin. RESULTS: No significant differences were found in PRI between CHD group and healthy control group [(89.45∓5.22)% vs (86.58∓4.35)%] before treatment. The PRI in CHD group was significantly lowered after treatment to (67.66∓19.77)% (P<0.05). Clopidogrel resistance was found in 6 (30%) cases in CHD group by flow cytometric analysis, which showed a higher sensitivity than optical nephelometry (10%). CONCLUSION: Flow cytometric analysis of VASP phosphorylation is a more reliable test to specifically evaluate clopidogrel resistance.