Qiao Liao

SphK1 confers resistance to apoptosis in gastric cancer cells by downregulating Bim via stimulating Akt/FoxO3a signaling

We previously reported that sphingosine kinase 1 (SphK1), an enzyme that catalyzes the production of sphingosine- 1-phosphate (SIP), is upregulated in human gastric cancer and predicts poor clinical outcome. In the present study, we used known differential effects of UV irradiation on human MGC-803 gastric cancer cells to determine their effect on SphK1 activity. Ectopic expression of SphK1 in MGC-803 gastric cancer cells markedly enhanced their resistance to UV irradiation, whereas silencing endogenous SphK1 with shRNAs weakened this ability. Furthermore, these antiapoptotic effects were significantly associated with decrease of Bim, an apoptosis-related protein. We further demonstrated that SphK1 could downregulate the transcriptional activity of forkhead box O3a (FoxO3a) by inducing its phosphorylation, which was found to be associated with the PI3K/Akt signaling. Taken together, our study supports the theory that SphK1 confers resistance to apoptosis in gastric cancer cells via the Akt/FoxO3a/Bim pathway.

The Associations of HLA-A*02:01 and DRB1*11:01 with Hepatitis C Virus Spontaneous Clearance Are Independent of IL28B in the Chinese Population.

Spontaneous clearance of hepatitis C virus (HCV) occurs in 10–40% of the infections. Specific human leukocyte antigen (HLA) alleles have been identified in associating with HCV clearance. However, data on the association of HLA with the spontaneous clearance of HCV are scarce in the Chinese population. In the current study we studied the HLA class I and class II genes in 231 Chinese voluntary blood donors who had cleared HCV infection spontaneously compared to 429 subjects with chronic HCV infections. We also studied their IL28B SNP (rs8099917) genotype, since a number of investigators have found a strong association of IL28B with spontaneous or treatment induced HCV clearance. We found that HLA-A*02:01 and DQB1*05:02 distributed differently between the two groups after Bonferroni correction (odds ratio [OR] = 1.839, Pc = 0.024 and OR = 0.547, Pc = 0.016, respectively). Multivariate logistic regression analysis suggested that A*02:01 and DRB1*11:01 (OR = 1.798, P = 0.008 and OR = 1.921, P = 0.005, respectively) were associated with HCV spontaneous clearance, independent of age, gender and IL28B polymorphism. We concluded that in the Chinese population, HLA-A*02:01 and DRB1*11:01 might be associated with the host capacity to clear HCV independent of IL28B, which suggesting that the innate and adaptive immune responses both play an important role in the control of HCV.

HLA-B alleles B∗15: 01 and B∗15:02: Opposite association with hepatitis C virus infection in chinese voluntary blood donors

Background: Although human leukocyte antigens (HLA) have been shown in association with the outcomes of hepatitis C virus (HCV) infection among different ethnic groups, such studies remain absent in China, where the HCV prevalence is higher than the global average. Methods: In this study, 426 HCV-infected and 709 uninfected blood donors were analyzed, among whom the HLA alleles were sequenced using a high-resolution genotyping method. Results: At the 2-digit level, none of the alleles showed a statistical difference between the HCV-infected and uninfected groups. However, at the 4-digit level, the HLA-B alleles B*15:01 and B*15:02 showed an opposite association with HCV infection, i.e. B*15:01 was significantly higher in the HCV-infected group (odds ratio, OR = 1.561, p = 0.010), while B*15:02 was significantly higher in the uninfected group (OR = 0.778, p = 0.016). We also identified a higher frequency of B*13:02 in the HCV-infected group (OR = 1.515, p = 0.009) and a higher frequency of B*07:05 in the uninfected group (OR = 0.299, p = 0.001). Conclusions: The frequencies of four HLA alleles, B*07:05, B*13:02, B*15:01, and B*15:02, were found to be significantly different between the HCV-infected and uninfected blood donors in China, revealing an inverse relation of B*15:01 and B*15:02 with HCV infection. This finding suggests that the ethnic genetic variations of HLA may greatly affect the host immune responses against HCV.

HBV/HCV co-infection is associated with a high level of HCV spontaneous clearance among drug users and blood donors in China

Understanding the biology of spontaneous clearance of hepatitis C virus (HCV) infection could lead to improved strategies to prevent the sequelae associated with chronic HCV infection. Chronic infections with hepatitis virus are very common in China, but the factors associated with spontaneous clearance of HCV have not been adequately studied. We evaluated the spontaneous clearance of HCV among 1918 drug users and 1526 HCV‐seropositive blood donors in Guangzhou, China. Among participants who were co‐infected with hepatitis B virus (HBV), 41.38% of drug users and 39.47% of blood donors had cleared their HCV infection without antiviral therapy compared to 9.41% of drug users and 16.73% of blood donors who were mono‐infected with a single virus (P<.01). The proportion of subjects who had cleared their HCV infection was significantly greater in the co‐infected subjects whose serum HBV DNA was greater than 2000IU/mL than those with lower levels. A multiple logistic regression analysis found female gender, IL28B rs8099917 TT genotype, HBV co‐infection and blood donors (vs drug users) associated with increased spontaneous clearance of HCV infection. Although acute HCV infections are common in China, the incidence of chronic HCV may be reduced among the high prevalence of chronic HBV and IL28B genotypes associated with spontaneous clearance of HCV in Chinese populations.

An evaluation of asymptomatic Dengue infections among blood donors during the 2014 Dengue outbreak in Guangzhou, China†

In 2014, an outbreak of dengue virus (DENV) infection led to 45 171 clinical cases diagnosed in Guangdong province, Southern China. However, the potential risk of blood donors asymptomatically infected with DENV has not been evaluated . In the current study we detected anti‐DENV IgG antibody and RNA in volunteer Chinese blood donors. We found that anti‐DENV IgG antibody was positively detected in 3.4% (51/1500) and two donors were detected as being DENV RNA positive out of 3000 blood samples. We concluded that the presence of potential DENV in blood donors might be potential risk for blood safety. Therefore, screening for DENV infection should be considered in blood donations during a period of dengue outbreak in high epidemic area of China.

Incidence of hepatitis B virus infection in young Chinese blood donors born after mandatory implementation of neonatal hepatitis B vaccination nationwide.

This study was carried out to determine the incidence of hepatitis B virus (HBV) infection in the young generation born after mandatory implementation of hepatitis B vaccination since 1992. Repeat blood donors born between 1992 and 1997 were enrolled, who gave blood at least twice during the past 3 years. Donors were tested for HBV infection markers of HBsAg, anti‐HBc, anti‐HBs and viral DNA by immunoassays (EIAs) and nucleic acid tests (NAT). A total of 14 937 pre‐donation screening qualified young repeat donors aged 18‐23 years were tested with 9 (0.06%) being HBsAg by EIA and 10 (1:1494) HBV DNA positive by Ultrio NAT (10.4 IU/mL), respectively. HBV DNA was further detected in 1:192 (9/1732) anti‐HBc+ repeat donors with Ultrio Plus NAT (3.4 IU/mL). Most cases were identified as occult HBV infection (OBI). Of 14 937 repeat donors, 20.9% were anti‐HBc+ positive, while approximately 50% of 12 024 repeat donors were anti‐HBs negative or had levels <100 IU/L. HBsAg+ or OBI strains were classified as wild type of genotype B or genotype C. Incident HBV infection in repeat donors was approximately 1:18.5 person‐years (1.1%/year) but significantly less frequent in donors with confirmed HBV vaccination (2.4%‐3.3%) than those unsure of vaccination status (10.5%; P = .0023). Hepatitis B virus vaccination appears largely protective of HBV infection, but incidence of infections increases in young adults with mostly undetectable or low anti‐HBs or occasionally high anti‐HBs. A boost of hepatitis B vaccine for adolescents prior to age 18 years may reduce HBV infection, and implementation of more sensitive NAT in blood donation screening may improve HBV safety in blood transfusion.

Molecular evolution of hepatitis C virus in China: A nationwide study

The evolutionary and epidemic history and the regional differences of hepatitis C virus (HCV) are complex and remain unclear in the vast territory China. Here we recruited 1540 HCV-RNA positive patients sampled in 29 provinces across whole China, which is the largest sample capacity and the most comprehensive geographic coverage of China to our knowledge. 1b, 2a, 3b, 6a and 3a were the major subtypes in China. 1b was the most predominant subtype which presented in every province. The second most predominant subtype, 2a, appeared to concentrate in the north of China. Subtypes 3a and 3b were mainly found in the Southwest region, while 6a was restricted in the South region. We further estimated the origins of the dominating subtypes and discovered for the first time that a Chinese-specific transmission pattern for some strains of subtype 2a which was restricted in north China, and Chinese subtype 3b originated from Thailand.

Association of killer cell immunoglobulin-like receptors with spontaneous clearance of hepatitis C virus in the Chinese population: KIR AND HCV SPONTANEOUS CLEARANCE

Natural killer (NK) cells are critical components in innate immune response to viral infection. Killer cell immunoglobulin‐like receptors (KIRs) are involved in regulating the balance of activation or inhibitory function of NK cells. However, the association of KIRs with the spontaneous clearance of hepatitis C virus (HCV) remains unclear in the Chinese population.

Characterization of monocytic and granulocytic subsets of myeloid-derived suppressor cells in blood donors with occult hepatitis B virus infection: ZHANG et al.

Myeloid‐derived suppressor cells (MDSCs) accumulate from many diseases. MDSCs are rarely explored in occult hepatitis B virus infection (OBI). The frequency of monocytic MDSCs (M‐MDSCs) and granulocytic MDSCs (G‐MDSCs) in OBI carriers was analyzed for correlation with clinical parameters, which was no different between OBI and healthy individuals, whereas the frequency of M‐MDSCs but G‐MDSCs in OBI was significantly lower than that observed in chronic hepatitis B carriers (0.4% vs 0.7%, P = 0.0004). The frequency of MDSCs was not correlated with clinical parameters and viral load of OBI, suggesting that the absence of HBsAg in OBI carriers might not induce the accumulation of MDSCs.

Low prevalence of human T lymphocyte virus in blood donors in Guangdong, China

Background: To investigate the prevalence of human T lymphocyte virus (HTLV) in blood donors in Guangdong province, China. Methods: The enzyme-linked immunosorbent assay (ELISA) was applied for primary screening of anti-HTLV-I/II antibodies in blood donors. Reactive samples were subjected to secondary detection using the electrochemiluminescence immunoassay (ECLIA). Samples reactive for both ELISA and ECLIA were further identified by nucleic acid testing (NAT) and Western-blot (WB). Results: A total of 2,058,790 samples collected from 20 blood stations across the whole province of Guangdong were screened through March 2016 to February 2018. Among them, 758 samples were reactive with ELISA, and 182 were reactive with followed ECLIA detection. Of ECLIA reactive samples, 43 were identified positive by NAT and WB, accounting for an overall positive rate of 0.002% (43/2,058,790). Forty-three positive samples were classified as HTLV-I, and no HTLV-II was identified. Conclusions: The prevalence of HTLV-I was approximately 1:50,000, that was low in blood donor population in Guangdong province. In term of blood safety, a leukocyte filtration for blood components might reduce the risk of HTLV-1 transmission in transfusion, which could be also considered as an alternative of high cost blood screening by the immunoassays and NAT for the viruses in blood donation.