[Effects of neonatal stimulator of interferon genes innate immune signaling pathway of HBsAg-positive mothers on non/hypo-response to hepatitis B vaccine in infants]

Objective: To explore the effects of neonatal stimulator of interferon genes (STING) innate immune signaling pathway of HBsAg-positive mothers on non/hypo-response to hepatitis B vaccine (HepB) in their infants. Methods: From November 2019 to June 2022, HBsAg-positive mothers and their infants in the Third People's Hospital of Taiyuan were recruited as the study subjects. The epidemiological and clinical data were collected by questionnaire survey and medical records review. The key molecular proteins of STING innate immune signaling pathway (STING, pIRF3) and immune cells associated with vaccine response (DC, T and B and plasma cells) in neonatal cord blood were detected by flow cytometry. Follow up was conducted for infants for 1-2 months after the full vaccination of HepB. Serum hepatitis B surface antibody (anti-HBs) was detected by chemiluminescence microparticle immunoassay. Unconditional logistic regression model, nomogram and Bayesian network model were used to evaluate the effect of STING innate immune signaling pathway on non/hypo-response to HepB and related factors in infants, and the relationship between various factors. Results: A total of 195 pairs of HBsAg-positive mothers and infants were recruited, the rate of non/hypo-response to HepB in the infants was 12.31% (24/195). High maternal HBV DNA load, low expression of neonatal STING, low expression of pIRF3 and low percentage of plasma cells were risk factors for non/hypo-response to HepB in the infants (OR=4.70, 3.46, 3.18 and 2.20, all P<0.05). The nomogram constructed by these factors had good predictive efficacy (area under curve=0.81, 95%CI: 0.63-0.83). The results of Bayesian network model showed that the infants with a high maternal HBV DNA load had a higher conditional probability of low STING expression (62.50%) and a higher conditional probability of low pIRF3 expression (58.54%). The conditional probabilities of low expression of DC, T, B and plasma cells were 53.16%, 60.20%, 68.42% and 57.14%, respectively. Conclusion: Maternal HBV DNA might inhibit STING innate immune signaling pathways in infants and immune cells associated with HepB response, resulting in non/hypo-response to HepB in infants of HBsAg-positive mothers.

Stability profiling and degradation products of dihydromyricetin in Dulbecco's modified eagle's medium

Dihydromyricetin has shown many bioactivities in cell level. However, dihydromyricetin was found to be highly instable in cell culture medium DMEM. Here, the underlying degradation mechanism was investigated via UPLC-MS/MS analysis. Dihydromyricetin was mainly converted into its dimers and oxidized products. At lower temperature, dihydromyricetin in DMEM showed higher stability. Vitamin C increased the stability of dihydromyricetin in DMEM probably due to its high antioxidant potential.

[Distributive characteristics of HBV DNA CpG islands in HBsAg positive mothers and its relationship with intrauterine transmission]

Objective: To investigate the type, length, and CG loci of HBV DNA CpG islands in HBsAg positive maternal C genotype and its relationship with intrauterine HBV transmission, so as to provide a new perspective for the study of intrauterine transmission of HBV. Methods: From June 2011 to July 2013, HBsAg-positive mothers and their newborns who delivered in the obstetrics and gynecology department of the Third People's Hospital of Taiyuan were collected. Epidemiological data were collected through face-to-face questionnaires and electronic medical records. Serum HBV markers and serum HBV DNA were detected by electrochemiluminescence and quantitative fluorescence PCR, respectively. Intrauterine transmission of HBV was determined by positive HBsAg and/or HBV DNA in femoral venous blood before injection of HBV vaccine/Hepatitis B immunoglobulin within 24 h of birth. A total of 22 mothers and their newborns with HBV DNA load ≥10⁶ IU/ml in intrauterine transmission were selected as the intrauterine transmission group, and 22 mothers with HBV DNA load ≥10⁶ IU/ml without intrauterine transmission were chosen as the control group by random seed method. The distribution prediction of CpG islands of HBV DNA in 39 mothers with genotype C by HBV DNA sequencing was analyzed. Results: Among 39 mothers with HBV C genotype, 19 were in the intrauterine transmission group, and 20 were in the control group. The HBV DNA of 39 patients with genotype C traditional CpG island Ⅱ and Ⅲ, while the control group had traditional CpG island Ⅰ and novel CpG island Ⅳ and Ⅴ. The length of CpG island Ⅱ and Ⅲ and the number of CG loci of CpG island Ⅱ in the intrauterine transmission group differed from those in the control group (P<0.05). The CpG island Ⅱ length ≥518 bp and the number of CG loci ≥40 in the intrauterine transmission group (11/19) were significantly higher than those in the control group (2/20) (P<0.05). The length of CpG island Ⅱ and the number of CG loci in the X gene promoter region (Xp region) were higher than those in the control group (P<0.05). In the HBV intrauterine transmission group, most of maternal (12/19) HBV DNA CpG island Ⅱ completely covered the Xp region, which was significantly higher than that in the control group (5/20), and the number of HBV DNA Xp region CG loci was higher than that in the control group (P<0.05). Conclusions: The distribution of maternal C genotype HBV DNA CpG islands is related to intrauterine transmission. The length of CpG island Ⅱ and the number of CG sites may increase the risk of intrauterine transmission of HBV.

[Effect of activation of Toll-like receptor signaling pathway of peripheral blood mononuclear cell in recombinant hepatitis B surface antigen immune response]

Objective: To explore the effect and mechanism of activation of peripheral blood mononuclear cell (PBMC) Toll-like receptor (TLR3) signaling pathway in recombinant HBsAg (rHBsAg) immune response. Methods: White blood cells were collected from peripheral blood of 13 healthy donors in the preparation of blood products. PBMC was isolated and treated with Poly I:C (Poly I:C group) and PBS (control group) respectively. 48 h later, some cells were collected and the expressions of TLR3 signaling pathway proteins were detected by flow cytometry. After activating (Poly I:C group)/inactivating (control group) TLR3 signaling pathway, rHBsAg was given to both groups for 72 h, and the proportions of DC, T, B cells and their subsets in PBMC were detected by flow cytometry. Paired t-test, paired samples wilcoxon signed-rank test and canonical correlation analyses were used for statistical analysis. Results: The percentage of TLR3 protein-positive cells (19.21%) and protein expression (8 983.95), NF-κB protein expression (26 193.13), the percentage of pNF-κB protein-positive cells (13.73%) and its proportion in NF-κB (16.03%), and the percentage of pIRF3 protein-positive cells (12.64%) and its proportion in IRF3 (21.80%) in Poly I:C group were higher than those in control group (11.54%, 8 086.00, 22 340.66, 8.72%, 9.71%, 9.57%, 19.12%) (P<0.05), and the percentage of TRIF protein-positive cells (89.75%) and protein expression (304 219.54) were higher in Poly I:C group than in the control group (89.64%, 288 149.72) (P>0.05). After PBMC stimulation by rHBsAg, the proportions of mDC (2.90%), pDC (1.80%), B cell (5.31%) and plasma cell (67.71%) in Poly I:C group were significantly higher than those in the control group (1.83%, 0.81%, 4.23%, 58.82%) (P<0.05). Results of canonical correlation analysis showed that the expression of TLR3 protein was positively correlated with the proportions of plasma cells, the expression of pIRF3 protein was positively correlated with the proportions of plasma cells and mDC, and the percentage of pNF-κB protein-positive cells and the percentage of pIRF3 protein-positive cells were positively correlated with the proportion of CD4⁺T cells. Conclusions: Poly I:C can activate TLR3/TRIF/NF-κB and TLR3/TRIF/IRF3 signaling pathway, promote the function of downstream signaling molecules, and then promote the maturation of DC, induce the immune responses of CD4⁺T cell, and promote the maturation and activation of B cells and the immune response of rHBsAg.

[Relationship between C genotype HBV mutation and intrauterine transmission]

Objective: To analyze the virus genome mutation of mothers with C genotype HBV and explore its relationship with HBV intrauterine transmission. Methods: A total of 399 mothers carrying HBV and their newborns hospitalized in the obstetrics department of the Third People's Hospital of Taiyuan from 2011 to 2013 were selected. Necessary information about mothers and children was obtained through a questionnaire survey and medical records. HBV DNA and HBV serological markers were detected by quantitative fluorescence PCR and electrochemiluminescence. Within 24 hours after birth and before active/passive immunization, those with positive HBsAg and/or HBV DNA in femoral venous blood were determined as HBV intrauterine transmission. According to the requirements of cloning and sequencing, mothers' HBV DNA load should be ≥10⁶ IU/ml. Among 54 cases of HBV intrauterine transmission, 22 pairs of mothers and their newborns meeting the requirements of cloning and sequencing were used as the intrauterine transmission group. The same number of mothers and their newborns without intrauterine transmission was selected as the random seed method's control group. After PCR amplification of HBV DNA, gene cloning, and sequencing, the gene mutation analysis of mothers with C genotype HBV was performed. Results: Among the 44 samples, 39 (88.63%, 39/44) were genotype C, 2 were genotype B, and 3 were mixed genotype B, and C. A total of 406 clone beads from 42 mothers with C genotype HBV were analyzed for gene mutation, including 204 in the intrauterine transmission group and 202 in the control group. The base substitution mutation rate of PreS1, S, C, and P regions in the HBV intrauterine transmission group were significantly lower than those in the control group (χ² ranged from 8.67 to 40.73, P<0.05). The mutation rate of base deletion in PreC and X regions in the HBV intrauterine transmission group was lower than that in the control group (χ² values were 17.82 and 34.78, P<0.001). Two clones in the X region had 31 bp insertion mutations between nt1644 and nt1645, and two clones had 27 bp insertion mutations between nt1649 and nt1650, all of which took place in the control group. Conclusions: The base substitution mutations in the PreS1, S, C, and P segments of the HBV genome in mothers with C genotype HBV were associated with the occurrence of intrauterine transmission of HBV. Deletion mutations in the PreC region, insertion and deletion mutations in the X region may reduce intrauterine transmission risk.

[Relationship between mutations of HBV basal core promoter region in HBsAg-positive mothers and intrauterine transmission]

Objective: To analyze the relationship between maternal mutations in basal core promoter region of hepatitis B virus (HBV) genotype C and intrauterine transmission. Methods: We collected information on general demographic characteristics and process of delivery among 399 pairs of consecutive HBsAg-positive mothers and their neonates, from the Third People's Hospital of Taiyuan in Shanxi province, China. Fluorescence quantitative polymerase chain reaction (FQ-PCR) and Electro-chemiluminescence immuno-assay (ECLIA) kits were used to detect both maternal and neonatal HBV DNA and serological markers in the peripheral blood. From 113 mothers with HBV DNA load ≥10(6) IU/ml, we selected 22 mothers whose neonates were with intrauterine transmission and randomly selected the same number of mothers whose neonates were without intrauterine transmission, as controls. The whole-length HBV DNA were extracted, amplified, cloned, sequenced and genotyped. Finally, a total of 39 mothers with genotype C of HBV were selected for mutation analysis. Results: Thirty-nine cases of genotype C (88.63%) were finally included in the study, with 19 cases in the intrauterine transmission group and 20 cases as controls. Rates of A1762T/G1764A double mutations were significantly different between the intrauterine transmission group and the control group (7.53% vs. 27.72%, P<0.001). Results from the multivariate analysis showed that the A1762T/G1764A double mutations had reduced the risk of intrauterine transmission (aOR=0.065, 95%CI: 0.006-0.746, P=0.028). Maternal A1762T/G1764A double mutations appeared to be possibly associated with neonatal HBeAg (P=0.050). Conclusion: A1762T/G1764A double mutations of HBV DNA from the genotype C of those HBsAg-positive mothers could reduced the risk of HBV intrauterine transmission during pregnancy.

MicroRNA-206 functions as a tumor suppressor in colorectal cancer by targeting FMNL2

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers in the world. MicroRNAs play important roles in the progression of CRC. This study aimed to investigate the role of miR-206 and its novel mechanism in the invasion and metastasis of CRC.

METHODOLOGY

Real-time RT-PCR or Western blotting was used to detect the expressions of miR-206, FMNL2 and c-MET in CRC cell lines and tissues. Luciferase reporter assays were conducted to detect the associations between miR-206 and 3'UTRs of FMNL2 and c-MET. A series of loss-of-function and gain-of-function assays were performed to evaluate the effect of miR-206 on the proliferation, invasion and metastasis of CRC cells.

RESULTS

miR-206 was significantly down-regulated in CRC tissues and correlated closely with differentiation, lymphatic metastasis and serosal invasion. miR-206 suppressed CRC cell proliferation by arresting CRC cells in the G1/G0 phase and accelerating apoptosis. miR-206 also inhibited cell invasion and lung metastasis in CRC cells. Mechanically, FMNL2 and c-MET were identified as direct targets of miR-206. And FMNL2 rescued the suppression of miR-206 in the proliferation and invasion of CRC cells.

CONCLUSIONS

This study revealed functional and mechanistic links between miR-206 and oncogene FMNL2 and c-MET in the progression of CRC. miR-206 functioned as a tumor suppressor in the progression of CRC by targeting FMNL2 and c-MET. Restoration of miR-206 expression may represent a promising therapeutic approach for targeting malignant CRC.

Anti-inflammatory effect of Houttuynia cordata injection

Houttuynia cordata (Saururaceae) injection (HCI) is a traditional Chinese medicine used in China. It was chosen as one of eight types of traditional Chinese medicine that play a unique role in severe acute respiratory syndrome (SARS) owing to the effect of curbing inflammation. In order to validate this plausible anti-inflammatory property, the chemical composition of HCI has been analysed by GC/MS, 22 components were identified, and the inflammation induced by carrageenan in the rat pleurisy model and by xylene in the mice ear edema model was adopted to study the anti-inflammatory activity of HCI. Injection of carrageenan into the pleural cavity elicited an acute inflammatory response characterized by protein rich fluid accumulation and leukocyte infiltration in the pleural cavity. The peak inflammatory response was obtained at 24 h when the fluid volume, protein concentration, C-reactive protein and cell infiltration were maximums. The results showed that these parameters were attenuated by HCI at any dose and touched bottom at dose of 0.54 ml/100 g, although less strong than dexamethasone. This drug was also effective in inhibiting xylene induced ear edema, and the percentage of inhibition came to 50% at dose of 80 microl/20 g. The results clearly indicate that HCI have anti-inflammatory activity.