Restoration of CD3+CD56+ NKT-like cell function by TIGIT blockade in inactive carrier and immune tolerant patients of chronic hepatitis B virus infection.

Chronic hepatitis B (CHB) virus infection, which can be divided into immune-tolerant (IT), immune-active (IA), inactive carrier (IC) phases, and HBeAg-negative hepatitis (ENEG), can induce liver cirrhosis and eventually hepatocellular carcinoma (HCC). CD3+CD56+ NKT-like cells play an important role in antiviral immune response. However, the mechanism of NKT-like cells to mediate immune tolerance remains largely elusive. In this study, we observed circulating NKT-like cells from IC and IT CHB patients were phenotypically and functionally impaired, manifested by increased expression of inhibitory receptor TIGIT and decreased capacity of secreting antiviral cytokines. Besides, TIGIT+ NKT-like cells of IC and IT CHB patients expressed lower levels of cytotoxic cytokines than the TIGIT- subset. Furthermore, increased expression of CD155, the ligand of TIGIT, on plasmacytoid dendritic cells (pDCs) was detected in IC and IT CHB patients. Importantly, the co-culture of NKT-like cells and pDCs showed that NKT-like cells restored their antiviral ability after TIGIT blockade upon HBV peptide stimulation in IC and IT CHB patients. In conclusion, our findings suggest that the TIGIT pathway may mediate immune tolerance in IT CHB patients and lead to functional impairment in IC patients, indicating that TIGIT may be a potential therapeutic checkpoint for immunotherapy of CHB patients.

Phenotypic and functional exhaustion of circulating CD3+ CD56+ NKT-like cells in colorectal cancer patients.

CD3+ CD56+ NKT-like cells are crucial to antitumor immune surveillance and defense. However, research on circulating NKT-like cells in colorectal cancer (CRC) patients is limited. This investigation selected 113 patients diagnosed with primary CRC for preoperative peripheral blood collection. The blood from 106 healthy donors at the physical examination center was acquired as a healthy control (HC). The distribution of lymphocyte subsets, immunophenotype, and functional characteristics of NKT-like cells was comprehensively evaluated. Compared to HC, primary CRC patients had considerably fewer peripheral NKT-like cells in frequency and absolute quantity, and the fraction of NKT-like cells was further reduced in patients with vascular invasion compared to those without. The NKT-like cells in CRC patients had a reduced fraction of the activating receptor CD16, up-regulated expression of inhibitory receptors LAG-3 and NKG2A, impaired production of TNF-α and IFN-γ, as well as degranulation capacity. Moreover, the increased frequency of NKG2A+ NKT-like cells and the decreased expression of activation-related molecules were significantly correlated with tumor progression. In detail, NKG2A+ NKT-like cells indicated increased PD-1 and Tim-3 and reduced TNF-α than NKG2A- subgroup. Blocking NKG2A in vitro restored cytokine secretion capacity in NKT-like cells from CRC patients. Altogether, this research revealed that circulating NKT-like cells in CRC patients exhibited suppressive phenotype and functional impairment, which was more pronounced in NKG2A+ NKT-like cells. These findings suggest that NKG2A blockade may restore anti-tumor effector function in NKT-like cells, which provides a potential target for immunotherapy in CRC patients.

CD8+ T cells mediate antiviral response in severe fever with thrombocytopenia syndrome.

Severe fever with thrombocytopenia syndrome (SFTS), which is caused by a novel Bunyavirus, has gradually become a threatening infectious disease in rural areas of Asia. Studies have identified a severe cytokine storm and impaired humoral immune response in SFTS. However, the cellular immune response to SFTS virus (SFTSV) infection remains largely unknown. Here we report that SFTS patients had a cytokine storm accompanied by high levels of chemokines. CD8+ T cells in peripheral blood mononuclear cells of SFTS patients exhibited a more activated phenotype and enhanced the antiviral responses. They increased the expression of CD69 and CD25, secreted a higher level of IFN-γ and granzyme, and had a stronger proliferative ability than in healthy controls. In convalescent SFTS patients, the expression of CD69 and CD25 on CD8+ T cells was reduced. In addition, we found the ratio and cellularity of CD14+ CD16+ intermediate monocytes were increased in peripheral blood of SFTS patients. Both the expression of C-X-C motif chemokine ligand 10 (CXCL10) on CD14+ CD16+ intermediate monocytes and the expression of C-X-C motif chemokine receptor 3 (CXCR3) on CD8+ T cells increased dramatically in SFTS patients. Our studies reveal a potential pathway that CD8+ T cells rapidly activate and are mostly recruited by intermediate monocytes through CXCL10 in SFTSV infection. Our results may be of clinical relevance for further treatment and discharge instructions in SFTSV infections.

ICOS-ICOSL pathway enhances NKT-like cell antiviral function in pregnant women with COVID-19.

Objective: The immune response initiated by SARS-CoV-2 infection in pregnancy is poorly elucidated. We aimed to access and compare the antiviral cellular responses and lymphocytes activation between healthy pregnancies and pregnant women infected with SARS-CoV-2. Methods: We detected the immunological changes of lymphocytes in peripheral blood of healthy non-pregnant women, non-pregnant women with COVID-19, healthy pregnant women, pregnant women with COVID-19 and convalescent group by flow cytometry. In vitro blockade was used to identify NKT-like cell activation through ICOS-ICOSL pathway. Results: We found that CD3+CD56+ NKT-like cells decreased significantly in COVID-19 positive pregnant women compared to healthy pregnant women. NKT-like cells of pregnant women expressed higher level of activating receptors CD69 and NKp46 after SARS-CoV-2 infection. Particularly, they also increased the expression of the co-stimulatory molecule ICOS. NKT-like cells of pregnant women with COVID-19 up-regulated the expression of IFN-γ, CD107a and Ki67. Meanwhile, we found that ICOSL expression was significantly increased on pDCs in pregnant women with COVID-19. Blocking ICOS in vitro significantly decreased the antiviral activity of NKT-like cells in COVID-19 positive pregnant women, suggesting that ICOS-ICOSL may play an important role in the virus clearance by NKT-like cells. Conclusions: During SARS-CoV-2 infection, NKT-like cells of pregnant women activated through ICOS-ICOSL pathway and played an important role in the antiviral response.

Dysfunction of circulating CD3+CD56+ NKT-like cells in type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is associated with increased incidence and mortality of many cancers and infectious diseases. CD3+CD56+ NKT-like cells play pivotal roles in tumor surveillance and infection control. However, little is known about potential alterations in circulating NKT-like cells in T2DM patients. In this study, we found that the frequency and absolute counts of circulating NKT-like cells were significantly lower in patients with T2DM compared to healthy volunteers. Moreover, in T2DM patients, NKT-like cells were impaired in their production of IFN-γ and TNF-α as well as degranulation capacity. The expression of activating receptor NKG2D was markedly decreased on NKT-like cells in T2DM patients, while the expression of inhibitory receptors Tim-3 and LAG-3 was upregulated. In detail, Tim-3+NKT-like cells expressed higher LAG-3 and less IFN-γ and TNF-α compared to Tim-3-NKT-like cells. Importantly, we further found that the expression of Tim-3 in NKT-like cells from T2DM patients correlated positively with glycated hemoglobin (HbA1c) and fasting blood glucose (FBG) levels, as well as with diabetes duration. In conclusion, these results indicate that NKT-like cells from T2DM patients display an exhausted phenotype and reduced functionality. Moreover, Tim-3 expression on NKT-like cells likely serves a novel biomarker for duration of T2DM.

Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry as Internship Teaching Content in Laboratory Medicine.

BACKGROUND: Matrix-assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) is one of the preferred detection techniques for identification of clinical microorganisms and it has the characteristics of rapid identification, simple operation, low cost, and updatable databases. For laboratory medicine undergraduates, clinical internship is an important stage for the connection of basic theoretical knowledge and clinical practice. Internship teaching choosing MALDI-TOF MS as the content will greatly increase the popularity and applicability of the new technology in the clinical microbiology laboratory. METHODS: With the help of electronic databases on the network, we conducted a systematic review. According to the purpose of research, we singled out forty papers. Latest studies on history, basic principles, clinical features, and applications of MALDI-TOF MS and the internship teaching contents introducing new technologies are summarized and focused on. In internship teaching, firstly we explain the historical development, basic principle and widespread applications of MALDI-TOF MS in the identification of clinical pathogenic microorganisms and the detection of antibiotic resistance. Subsequently, we instruct the students to perform the experimental operations, analyze the common problems, and find solutions. Finally, we highlight quality control and laboratory biosafety. RESULTS: Most of the reviews published previously report the clinical features and applications of MALDI-TOF MS and the internship teaching contents choosing other new technologies. It is the first study selecting MALDI-TOF MS technology as an internship teaching content creatively. Primary outcome is that the students understand the theoretical knowledge in detail, master the operation skills of MALDI-TOF MS quickly, and obtain excellent internship performances in the clinical internship through the internship teaching. Secondary outcome is that it is a help to cultivate medical students' train of thought for scientific research and to understand the application of the new technology in clinical testing and scientific research. CONCLUSIONS: Laboratory medicine undergraduates should cherish the opportunity to learn the new technology during the internship period and should master basic principle and operation. As internship teachers, it is necessary to introduce the new technology to students during the internship and encourage undergraduates to cultivate creative and innovative thinking of scientific research.

IL-17 exacerbates experimental autoimmune prostatitis via CXCL1/CXCL2-mediated neutrophil infiltration.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a poorly understood disease. Accumulating evidence suggests that autoimmune dysfunction is involved in the development of CP/CPPS. Interleukin-17 (IL-17) is associated with the occurrence and development of several chronic autoimmune inflammatory diseases. However, the molecular mechanisms underlying the role of IL-17 in CP/CPPS are not clear. We confirmed that IL-17 was increased in the prostate tissues of experimental autoimmune prostatitis (EAP) mice. Corresponding to the increase of IL-17, neutrophil infiltration and the levels of CXCL1 and CXCL2 (CXC chemokine ligands 1 and 2) were also increased in the prostate of EAP. Treatment of EAP mice with an IL-17-neutralizing monoclonal antibody (mAb) decreased the number of infiltrated neutrophils and CXCL1 and CXCL2 levels. Depletion of neutrophils using anti-Ly6G antibodies ameliorated the inflammatory changes and hyperalgesia caused by EAP. Fucoidan, a could potent inhibitor of neutrophil migration, also ameliorate the manifestations of EAP. Our findings suggested that IL-17 promoted the production of CXCL1 and CXCL2, which triggered neutrophil chemotaxis to prostate tissues. Fucoidan might be a potential drug for the treatment of EAP via the effective inhibition of neutrophil infiltration.

Activated autophagy restored the impaired frequency and function of regulatory T cells in chronic prostatitis.

BACKGROUND: Chronic prostatitis or chronic pelvic pain syndrome (CP/CPPS) is a disease with an unclear pathogenesis. Recent studies have reported that regulatory T (Treg) cells might be involved in the development of CP/CPPS. In this study we aimed to examine the functional role of Treg cells and explore the possible regulatory mechanism of Treg cells in CP/CPPS. METHODS: An experimental autoimmune prostatitis (EAP) mouse model was constructed; the numbers and functions of Treg cells in the EAP and control groups were tested. Then, cell differentiation experiments were conducted to evaluate the regulatory effect of autophagy on Treg cell differentiation. Furthermore, autologous CD4+ CD25- cells and CD4+ CD25+ cells from the two groups were magnetically sorted and cocultured to observe differences in cellular inhibitory functions. Finally, in an in vivo experiment, rapamycin was intraperitoneally injected into EAP mice for 4 weeks to observe the therapeutic effects. RESULTS: We found that the number and function of Treg cells in the EAP group were diminished compared to those in the control group. Meanwhile, the tolerance of pain in EAP mice had also decreased. Moreover, after using the autophagy activator rapamycin, the expression of the inflammatory cytokines interleukin-1ß was decreased and the pain symptoms were alleviated. A mechanistic study found that autophagy activation promoted the differentiation of Treg and increased the suppressive functions of Treg cells, along with the elevated expression of GATA-3 and cytotoxic T lymphocyte antigen 4 (CTLA-4). Furthermore, in vivo administration of the autophagy activator rapamycin had similar effects on recovering the frequency and function of Treg cells as well as the expression of GATA-3 and CTLA-4. CONCLUSION: The impaired frequency and function of Treg cells may contribute to the progression of CP/CPPS, and autophagy is a protective mechanism that promotes the differentiation of Treg cells and restores the suppressive functions of Treg cells. Autophagy may be a novel therapeutic option for patients with CP/CPPS.

CaMK4-dependent phosphorylation of Akt/mTOR underlies Th17 excessive activation in experimental autoimmune prostatitis.

Chronic prostatitis and chronic pelvic pain syndrome (CP/CPPS) is a complicated syndrome characterized by genitourinary pain in the absence of bacterial infection. Th17 cell-driven autoimmunity has been proposed as a cause of CP/CPPS. However, the factors that promote Th17-driven autoimmunity in experimental autoimmune prostatitis (EAP) and the molecular mechanisms are still largely unknown. Here, we showed that Th17 cells were excessively activated, and blockade of IL-17A could effectively ameliorate various symptoms in EAP. Furthermore, we revealed that calcium/calmodulin-dependent kinase Ⅳ (CaMK4), especially Thr196 p-CaMK4 was increased in the Th17 cells of the EAP group, which were activated by intracellular cytosolic Ca2+ . Pharmacologic and genetic inhibition of CaMK4 decreased the proportion of Th17 cells, and the protein and mRNA level of IL-17A, IL-22, and RORγt. The phosphorylation of CaMK4 was dependent on the increase in intracellular cytosolic Ca2+ concentration in Th17 cells. A mechanistic study demonstrated that inhibition of CaMK4 reduced IL-17A production by decreasing the phosphorylation of Akt-mTOR, which was well accepted to positively regulate Th17 differentiation. Collectively, our results demonstrated that Ca2+ -CaMK4-Akt/mTOR-IL-17A axis inhibition may serve as a promising therapeutic strategy for CP/CPPS.

Human CD96 Correlates to Natural Killer Cell Exhaustion and Predicts the Prognosis of Human Hepatocellular Carcinoma.

Immune checkpoint blockade has become a promising therapeutic approach to reverse immune cell exhaustion. Coinhibitory CD96 and T-cell immunoglobulin and ITIM domain (TIGIT), together with costimulatory CD226, bind to common ligand CD155. The balancing between three receptors fine-tunes immune responses against tumors. In this study, we investigated the expression of CD96, TIGIT, and CD226 in 55 fresh human hepatocellular carcinoma (HCC) samples, 236 paraffin-embedded HCC samples, and 20 normal human livers. The cumulative percentage, absolute count, and mean fluorescence intensity (MFI) of CD96+ NK cells are significantly increased in the intratumoral tissues of HCC and break the balance between three receptors. Human CD96+ NK cells are functionally exhausted with impaired interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) production, high gene expression of interleukin (IL)-10 and transforming growth factor-beta 1 (TGF-ß1), and low gene expression of T-bet, IL-15, perforin, and granzyme B. In addition, blocking CD96-CD155 interaction specifically increases lysis of HepG2 cells by NK cells. HCC patients with a high level of CD96 or CD155 expression within tumor are strongly associated with deteriorating disease condition and shorter disease-free survival (DFS) and overall survival times. Patients with a higher cumulative percentage of CD96+ NK cells within tumor also exhibit shorter DFS. High plasma level of TGF-ß1 in HCC patients up-regulates CD96 expression and dynamically shifts the balance between CD96, TIGIT, and CD226 in NK cells. Blocking TGF-ß1 specifically restores normal CD96 expression and reverses the dysfunction of NK cells. Conclusion: These findings indicate that human intratumoral CD96+ NK cells are functionally exhausted and patients with higher intratumoral CD96 expression exhibit poorer clinical outcomes. Blocking CD96-CD155 interaction or TGF-ß1 restores NK cell immunity against tumors by reversing NK cell exhaustion, suggesting a possible therapeutic role of CD96 in fighting liver cancer.

CD8+ T Cells Promote Maturation of Liver-Resident NK Cells Through the CD70-CD27 axis.

Liver-resident natural killer (LrNK) cells are a unique subset of NK cells that are distinct from conventional NK cells. However, little is known about the mechanisms by which LrNK cells mature. In this study, we discovered that LrNK cells exhibit a relatively immature phenotype and impaired cytotoxic capacity in the absence of CD8+ T cells. The provision of CD8+ T cells to Cd8-/- or Rag1-/- mice led to the restoration of LrNK cell maturation. Furthermore, co-culture with CD8+ T cells induced immature CD27+ LrNK cells to convert into mature CD27- LrNK cells, whereas blocking the interaction of CD70 and CD27 abrogated the ability of CD8+ T cells to promote the maturation of LrNK cells. Conclusion: Our findings indicate that CD8+ T cells promote the maturation of LrNK cells through the CD70-CD27 axis, and therefore highlight a previously unknown mechanism responsible for the mediation of LrNK cell maturation.

Acute effects of sitagliptin on progenitor cells and soluble mediators in newly diagnosed type 2 diabetes.

OBJECTIVE: Studies have confirmed that endothelial progenitor cells (EPCs) are involved in diabetic complications. The present study assessed the action of the dipeptidyl peptidase-4 inhibitor sitagliptin on EPCs in newly diagnosed type 2 diabetes patients. MATERIALS AND METHODS: 60 newly-diagnosed type 2 diabetes patients were randomly divided into three treatment groups: sitagliptin (n = 20), metformin (n = 20), and combination sitagliptin and metformin (n = 20). Patients were treated once daily for 3 days. Before and after each treatment, the number of EPCs and concentration of soluble mediators (glucagon-like peptide 1 (GLP-1), nitric oxide (NO), endothelin-1 (ET-1), and stromal cell-derived factor-1α (SDF-1α)) were determined. RESULTS: The number of CD34+KDR+ and CD34+CD133+KDR+ EPCs and concentration of GLP-1, NO, and SDF-1α in sitagliptin and combination groups were both increased (both p < 0.05) but to a greater extent in the combination group (p < 0.05). Pearson correlation analysis and multiple linear regression analyses showed that the change in EPC numbers correlated with changes in peripheral GLP-1, NO, and SDF-1α levels (p < 0.05). CONCLUSION: Sitagliptin is able to directly increase the number of peripheral blood EPCs. This direct effect is to be important for lowering vascular risk in early diabetes before macrovascular complications appear.

Inhibition of Suicidal Erythrocyte Death by Indirubin-3'-Monoxime.

BACKGROUND/AIMS: Qing Dai is a prized traditional Chinese medicine whose major component, indirubin, and its derivative, indirubin-3'-monoxime (IDM), have inhibitory effects on the growth of many human tumor cells and pronounced anti-leukemic activities. However, the effects of IDM on mature human erythrocytes are unclear. This study aimed to evaluate the potential impact of IDM on erythrocytes and the mechanisms underlying that impact. METHODS: Utilizing flow cytometry and confocal laser scanning microscopy, phosphatidylserine exposure at the cell surface was estimated by annexin V-fluorescein isothiocyanate (FITC). The relative cell size, expressed in arbitrary units, was evaluated by forward scatter in a flow cytometer. Fluo-3 fluorescence was used to bewrite changes in cytosolic Ca2+ activity, reactive oxygen species (ROS) formation was assessed by 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescence, and ceramide abundance was evaluated by FITC-conjugated specific antibodies. RESULTS: The 24-h exposure of human erythrocytes to IDM (12 µM) significantly decreased the percentage of annexin V-binding erythrocytes and the intracellular calcium concentration ([Ca2+]i). IDM (3-12 µM) did not significantly modify the ceramide level or DCFH-DA fluorescence. Energy depletion (removal of glucose for 24 hours) significantly increased annexin V binding and Fluo-3 fluorescence and diminished forward scatter, and these effects were significantly mitigated by IDM (12 µM). Moreover, the Ca2+ ionophore ionomycin (1 µM, 60 min) and oxidative stress (30 min exposure to 0.05 mM tert-butyl hydroperoxide, t-BHP) similarly triggered eryptosis, which was also significantly suppressed by IDM. CONCLUSIONS: IDM is a novel inhibitor of suicidal erythrocyte death following ionomycin treatment, t-BHP treatment and energy depletion. Thus, IDM may counteract anemia and impairment of microcirculation, at least in part, by inhibition of Ca2+ entry into erythrocytes.

NK Cells Help Induce Anti-Hepatitis B Virus CD8+ T Cell Immunity in Mice.

Although recent clinical studies demonstrate that NK cell function is impaired in hepatitis B virus (HBV)-persistent patients, whether or how NK cells play a role in anti-HBV adaptive immunity remains to be explored. Using a mouse model mimicking acute HBV infection by hydrodynamic injection of an HBV plasmid, we observed that although serum hepatitis B surface Ag and hepatitis B envelope Ag were eliminated within 3 to 4 wk, HBV might persist for >8 wk in CD8(-/-) mice and that adoptive transfer of anti-HBV CD8(+) T cells restored the ability to clear HBV in HBV-carrier Rag1(-/-) mice. These results indicate that CD8(+) T cells are critical in HBV elimination. Furthermore, NK cells increased IFN-γ production after HBV plasmid injection, and NK cell depletion led to significantly increased HBV persistence along with reduced frequency of hepatitis B core Ag-specific CD8(+) T cells. Adoptive transfer of IFN-γ-sufficient NK cells restored donor CD8(+) T cell function, indicating that NK cells positively regulated CD8(+) T cells via secreting IFN-γ. We also observed that NK cell depletion correlated with decreased effector memory CD8(+) T cell frequencies. Importantly, adoptive transfer experiments showed that NK cells were involved in anti-HBV CD8(+) T cell recall responses. Moreover, DX5(+)CD49a(-) conventional, but not DX5(-)CD49a(+) liver-resident, NK cells were involved in improving CD8(+) T cell responses against HBV. Overall, the current study reveals that NK cells, especially DX5(+)CD49a(-) conventional NK cells, promote the antiviral activity of CD8(+) T cell responses via secreting IFN-γ in a mouse model mimicking acute HBV infection.

Eryptosis as an Underlying Mechanism in Systemic Lupus Erythematosus-Related Anemia.

BACKGROUND: The progression of systemic lupus erythematosus (SLE) leads to anemia in patients, adversely affecting prognosis. The diverse causes of anemia may include excessive eryptosis or premature suicidal erythrocyte death characterized by cell shrinkage and phosphatidylserine (PS) exposure on the cell surface. The present study explored if SLE enhances eryptosis and the underlying mechanisms. MATERIALS AND METHODS: Eryptosis was assessed using flow cytometry in healthy volunteers (n = 20) and anemic patients hospitalized for SLE (n = 22), for parameters including PS exposure, cell volume, cytosolic calcium ion (Ca2+) levels and reactive oxygen species (ROS) and ceramide abundance. These indicators were measured in erythrocytes of experimental subjects and erythrocytes treated with plasma from healthy volunteers or SLE patients. RESULTS: The hemoglobin and hematocrit levels were significantly lower in anemic SLE patients than in healthy volunteers (***p<0.001, p<0.001, respectively). The percentage of PS-exposing erythrocytes was significantly higher in SLE patients than in healthy volunteers (p<0.001), accompanied by an increase in cytosolic Ca2+ levels, oxidative stress. The measurements of PS and Ca2+ levels were significantly higher in the erythrocytes of healthy volunteers following incubation in plasma of SLE patients than in plasma of healthy volunteers for 24h (***p<0.001, *p<0.05 respectively). CONCLUSION: Eryptosis is enhanced in SLE and may contribute to anemia. The probable underlying mechanisms may be an excessive formation of ROS in erythrocytes. Also, some plasma components may trigger eryptosis by increasing the cytosolic Ca2+ concentration.

KEAP1 overexpression is correlated with poor prognosis and immune infiltration in liver hepatocellular carcinoma.

Purpose: Liver hepatocellular carcinoma (LIHC) is the most common type of liver cancer, but there is a lack of effective indicators for its early diagnosis and prognosis, so we explored the role of KEAP1 in LIHC patients in this study. Methods: The Cancer Genome Atlas (TCGA) dataset was used to investigate the relationship between KEAP1 expression and clinicopathological features and prognosis of LIHC patients. KEAP1 expression related pathways were enriched by Gene Ontology (GO) and gene set enrichment analysis (GSEA). Besides, KEAP1 expression-related immune infiltration was performed by single-sample GSEA (ssGSEA), and function of immune cells was detected by flow cytometry. Results: It was found that KEAP1 expression was significantly increased and correlated with overall survival of LIHC patients. A total of 231 differentially expressed genes (DEGs) between LIHC patients with high- and low-KEAP1 expression were found, which associated with various biological pathways. Besides, KEAP1 expression was positively correlated with the infiltration level of T helper cells and Th2 cells but negatively correlated with DCs and cytotoxic cells. Functional analysis revealed that the expression of IL 4 in Th2 cells and CD107a, GrA and GrB in cytotoxic cells was significantly greater in LIHC patients than in HCs. In addition, KEAP1 expression was closely correlated with liver function in LIHC patients. Conclusion: Highly expressed KEAP1 was closely related to the diagnosis, prognosis, immune cell infiltration, and liver function of LIHC, which might promote the progression of LIHC through regulating cell development, signal transduction, and abnormal immune response. The current study partially revealed the role of KEAP1 in LIHC and provided a potential biomarker for the diagnosis, prognosis and treatment of LIHC.

Atrial natriuretic peptide T2238C gene polymorphism and the risk of cardiovascular diseases: A meta­analysis.

The present study aimed to investigate the association between atrial natriuretic peptide (ANP) T2238C (rs5065) gene polymorphism and the risk of cardiovascular disease. Relevant literature was obtained by searching databases. The odds ratios (ORs) of the ANP T2238C locus genotype distribution in the case group of cardiovascular diseases and the control group of a non-cardiovascular population were pooled using R software. Sensitivity analysis was used to verify the stability of the results. Egger's linear regression test was used to assess the publication bias of the included literature. Studies were classified according to quality assessment score of the Newcastle-Ottawa scale, year, region, sample size and underlying disease for subgroup analysis, and meta-regression analysis was performed. A total of 12 studies comprising 45,619 patients were included. ANP rs5065 mutant gene C allele was a significant risk factor for myocardial infarction relative to T allele (OR=2.55, 95% CI=1.47-4.43, P=0.0008), CC+CT genotype was a significant risk factor for cerebrovascular events relative to TT (OR=1.14, 95% CI=1.04-1.26, P=0.0048) and the mutant CC genotype was a potential risk factor for the composite cardio-cerebral vascular events (CVE) relative to CT+TT (OR=1.40, 95% CI=0.96-2.04, P=0.081). In studies fulfilling the Hardy-Weinberg equilibrium, the CC genotype was a significant risk factor for the composite CVE relative to TT (OR=2.39, 95% CI=1.40-4.10, P=0.0018) and the CC genotype was a significant risk factor for composite CVE relative to CT+TT (OR=2.41, 95% CI=1.41-4.13, P=0.0015). The P-value of the Egger's test for publication bias was 0.436, which was not statistically significant. The results of the sensitivity analysis were relatively stable. Subgroup analysis indicated that the publication year was a potential source of heterogeneity. Regression analysis was performed for the recessive model in the composite CVE and the results showed that the study region (Europe) was one of the sources of heterogeneity (P=0.016). In conclusion, ANP 2238T/C mutation may increase the risk of myocardial infarction, cerebrovascular events and composite CVE.

PDCD4 promotes inflammation/fibrosis by activating the PPAR­Î³/NF­κB pathway in mouse atrial myocytes.

Fibrosis is the basis of structural remodeling in atrial fibrillation (AF), during which inflammation is crucial. Programmed cell death factor 4 (PDCD4) is a newly identified inflammatory gene, with unknown mechanisms of action in AF. The present study aimed to elucidate the effects of PDCD4 on the inflammation and structural remodeling of atrial myocytes. For this purpose, a PDCD4 overexpression plasmid (oePDCD4) and PDCD4 small interfering (si)RNA (siPDCD4) were used to modulate PDCD4 expression in mouse atrial myocytes (HL­1 cells). The expression of PDCD4 was detected using reverse transcription­quantitative PCR and western blot analysis. The optimal drug concentrations of peroxisome proliferator­activated receptor γ (PPARγ) agonist (pioglitazone hydrochloride), NF­κB inhibitor (CBL0137), PPARγ inhibitor (GW9962) and NF­κB agonist (betulinic acid) were screened using a Cell Counting Kit­8 assay. The levels of inflammatory factors were detected using enzyme­linked immunosorbent assays, the expression levels of fibrosis­related proteins and NF­κB subunits were detected using western blot analysis, and the expression of phosphorylated (p­)p65/p65 was detected using immunofluorescence staining. The results revealed that PDCD4 overexpression increased the levels of fibrotic factors (collagen I, collagen III, fibronectin, α­smooth muscle actin and matrix metalloproteinase 2), pro­inflammatory cytokines (IFN­Î³, IL­6, IL­17A and TNF­α) and p­p65, whereas it reduced the levels of anti­inflammatory cytokines (IL­4) in HL­1 cells. Additionally, treatment with the PPARγ agonist and NF­κB inhibitor reversed the levels of fibrotic­, pro­inflammatory and anti­inflammatory factors in oePDCD4­HL­1 cells. By contrast, PDCD4 silencing exerted the opposite effects on fibrotic factors, pro­inflammatory cytokines, anti­inflammatory cytokines and p­p65. In addition, treatment with the PPARγ inhibitor and NF­κB agonist reversed the levels of fibrotic­, pro­inflammatory and anti­inflammatory factors in siPDCD4­HL­1 cells. In conclusion, the present study demonstrated that PDCD4 may induce inflammation and fibrosis by activating the PPARγ/NF­κB signaling pathway, thereby promoting the structural remodeling of atrial myocytes in AF.

Immunogenic and diagnostic potential of recombinant apical membrane antigen-1 from Plasmodium malariae.

The apical membrane antigen-1 (AMA-1) is a crucial target for malaria management and prevention strategies. While the immunogenicity of AMA-1 has been extensively studied for Plasmodium falciparum and Plasmodium vivax, there is a notable scarcity of information for Plasmodium malariae. In this study, recombinant PmAMA-1 was expressed in Escherichia coli, and its integrity was confirmed via western blotting and indirect immunofluorescence assays. Immunization of BALB/c mice with rPmAMA-1 emulsified in Freund's adjuvant resulted in significantly elevated specific IgG antibodies, predominantly IgG1. The immune response exhibited Th1, Th2, and Th17 phenotypes, with a notable Th1 bias. Antisera from immunized mice effectively recognized native PmAMA-1 on P. malariae. These results suggest that PmAMA-1 is a promising target for both vaccine development and diagnostic applications for P. malariae infections, offering dual preventive and diagnostic benefits in malaria control.