Gene expression levels and enzymatic activities of copper/zinc superoxide dismutase (Cu/Zn‐SOD), catalase (CAT), and glutathione peroxidase (GPx) in liver of hybrid tilapia, Oreochromis niloticus × Oreochromis aureus were analyzed after 12–72 h exposure to acidic and alkaline pH. Results showed that, compared with the control pH (pH 6.8), acidic pH exposure (pH 4.8 and 5.8) induced the expression levels and enzymatic activities of antioxidant enzymes. Slight alkaline exposure (pH 7.8) increased the transcript levels of CAT and GPx and the activity of GPx. Strong alkalization (pH 8.8) presented an inhibition on the antioxidant enzyme system, suggesting alkaline exposure may be more harmful to antioxidant activity in liver of hybrid tilapia than acidic exposure. Moreover, under acidic and slight alkaline exposure, mRNA expressions and activities of Cu/Zn‐SOD were significantly induced after 12 h exposure, whereas CAT and GPx reached the highest levels later, indicating Cu/Zn‐SOD play the dominant role at the initial stage, whereas CAT and GPx work later.

Background. The HLA-E gene is a member of the HLA-I gene family. Its genetic polymorphism is regarded as associated with numerous diseases. Establishing a rapid and accurate detection method of disease-related SNP sites in HLA-E is particularly important. Methods. Blood samples from 226 healthy blood donors and 228 leukemia patients were collected, and DNA was extracted. Three typing methods based on PCR-sequence-based typing, TaqMan genotyping, and high-resolution melting curve were established to identify rs76971248 (G>T). The Chi-square test was used for statistical analysis by SPSS. Results. Three methods based on PCR-SBT, TaqMan genotyping, and HRM were all able to identify rs76971248. The software for analyzing the results of HLA-E sequencing was easy to use, and the results were accurate. The frequency of rs76971248 in different types of leukemia patients was significantly lower than that in healthy blood donors ( p < 0.05 ). And the frequency of the G/G genotype in leukemia patients was significantly higher than that in healthy blood donors ( p < 0.05 ). Conclusions. For the screening of known SNP sites in large-scale populations, among the three methods, the TaqMan genotyping method had the advantage of shortest time consumption, simplest operation, and greatest specificity, which was the most appropriate method for this experiment. The analysis software for HLA-E gene sequencing needed to be further optimized. rs76971248 had a protective effect against leukemia. And the G/G genotype was a risk factor for leukemia.

IntroductionThe human leukocyte antigen (HLA) system plays a critical role in the human immune system and is strongly associated with immune recognition and rejection in organ transplantation. HLA typing method has been extensively studied to increase the success rates of clinical organ transplantation. However, while polymerase chain reaction sequence-based typing (PCR-SBT) remains the gold standard, cis/trans ambiguity and nucleotide sequencing signal overlay during heterozygous typing present a problem. The high cost and low processing speed of Next Generation Sequencing (NGS) also render this approach inadequate for HLA typing.Methods and materialsTo address these limitations of the current HLA typing methods, we developed a novel typing technology based on nucleic acid mass spectrometry (MS) of HLA. Our method takes advantage of the high-resolution mass analysis function of MS and HLAMSTTs (HLA MS Typing Tags, some short fragment PCR amplification target products) with precise primer combinations.ResultsWe correctly typed HLA by measuring the molecular weights of HLAMSTTs with single nucleotide polymorphisms (SNPs). In addition, we developed a supporting HLA MS typing software to design PCR primers, construct the MS database, and select the best-matching HLA typing results. With this new method, we typed 16 HLA-DQA1 samples, including 6 homozygotes and 10 heterozygotes. The MS typing results were validated by PCR-SBT.DiscussionThe MS HLA typing method is rapid, efficient, accurate, and readily applicable to typing of homozygous and heterozygous samples.