OsJMJ718, a histone demethylase gene, positively regulates seed germination in rice.

Seed vigor has major impact on the rate and uniformity of seedling growth, crop yield, and quality. However, the epigenetic regulatory mechanism of crop seed vigor remains unclear. In this study, a (jumonji C) JmjC gene of the histone lysine demethylase OsJMJ718 was cloned in rice, and its roles in seed germination and its epigenetic regulation mechanism were investigated. OsJMJ718 was located in the nucleus and was engaged in H3K9 methylation. Histochemical GUS staining analysis revealed OsJMJ718 was highly expressed in seed embryos. Abiotic stress strongly induced the OsJMJ718 transcriptional accumulation level. Germination percentage and seedling vigor index of OsJMJ718 knockout lines (OsJMJ718-CR) were lower than those of the wild type (WT). Chromatin immunoprecipitation followed by sequencing (ChIP-seq) of seeds imbibed for 24 h showed an increase in H3K9me3 deposition of thousands of genes in OsJMJ718-CR. ChIP-seq results and transcriptome analysis showed that differentially expressed genes were enriched in ABA and ethylene signal transduction pathways. The content of ABA in OsJMJ718-CR was higher than that in WT seeds. OsJMJ718 overexpression enhanced sensitivity to ABA during germination and early seedling growth. In the seed imbibition stage, ABA and ethylene content diminished and augmented, separately, suggesting that OsJMJ718 may adjust rice seed germination through the ABA and ethylene signal transduction pathways. This study displayed the important function of OsJMJ718 in adjusting rice seed germination and vigor, which will provide an essential reference for practical issues, such as improving rice vigor and promoting direct rice sowing production.

Tislelizumab plus chemotherapy versus pembrolizumab plus chemotherapy for the first-line treatment of advanced non-small cell lung cancer: systematic review and indirect comparison of randomized trials.

Purpose: Pembrolizumab and tislelizumab have demonstrated significant clinical benefits in first-line treatment for advanced NSCLC. However, no head-to-head clinical trial has ever compared the optimal choice. Therefore, we conducted an indirect comparison to explore the optimal choice for advanced NSCLC combined with chemotherapy. Methods: We conducted a systematic review of randomized trials; the clinical outcomes included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs). Indirect comparisons between tislelizumab and pembrolizumab were conducted with the Bucher method. Results: Data were abstracted from 6 randomized trials involving more than 2,000 participants. Direct meta-analysis showed that both treatment regimens improved clinical outcomes compared with chemotherapy alone (PFS: hazard ratio (HR)tis+chemo/chemo 0.55, 95% CI 0.45-0.67; HRpem+chemo/chemo 0.53, 95% CI 0.47-0.60; ORR: relative risk (RR)tis+chemo/chemo 1.50, 95% CI 1.32-1.71; RRpem+chemo/chemo 1.89, 95% CI 1.44-2.48). Regarding safety outcomes, tislelizumab and pembrolizumab have a higher risk in the incidence of grade 3 or higher AEs (RRtis+chemo/chemo 1.12, 95% CI 1.03-1.21; RRpem+chemo/chemo 1.13, 95% CI 1.03-1.24). The indirect comparison showed that there was no significant difference between tislelizumab plus chemotherapy and pembrolizumab plus chemotherapy in terms of PFS (HR: 1.04, 95% CI 0.82-1.31), ORR (RR: 0.79, 95% CI 0.59-1.07), the incidence of grade 3 or higher AEs (RR 0.99, 95% CI 0.87-1.12), and AEs leading to death (RR 0.70, 95% CI 0.23-2.09). In progression-free survival subgroup analysis, the results demonstrate no significant differences in PFS by PD-L1 TPS expression level, age, liver metastasis status, and smoking status between tislelizumab plus chemotherapy and pembrolizumab plus chemotherapy. Conclusion: The efficacy and safety of tislelizumab combination chemotherapy were not substantially different from pembrolizumab combination chemotherapy.

Pan-cancer analysis and experimental validation of DTL as a potential diagnosis, prognosis and immunotherapy biomarker.

BACKGROUND: DTL has been found to be related with multiple cancers. However, comprehensive analyses, which identify the prediction value of DTL in diagnosis, prognosis, immune infiltration and treatment, have rarely been reported so far. METHODS: Combined with the data online databases, the gene expression, gene mutation, function enrichment and the correlations with the immunity status and clinical indexes of DTL were analyzed. Expression of DTL and the degree of immune cell infiltration were examined by immunofluorescence (IF) and immunohistochemistry (IHC) and analyzed by statistical analysis. Furthermore, the influences of DTL on the cell cycle, cell proliferation and apoptosis were detected by live cell imaging, IF and flow cytometric (FC) analysis. Genomic stability assays were conducted by chromosome slide preparation. RESULTS: DTL was widely expressed in various cells and tissues, while it was overexpressed in tumor tissues except acute myeloid leukemia (LAML). Pan-cancer bioinformatics analysis showed that the expression of DTL was correlated with the prognosis, immunotherapy, and clinical indexes in various cancers. In addition, gene set enrichment analysis (GSEA) uncovered that DTL was enriched in oocyte meiosis, pyrimidine metabolism, the cell cycle, the G2M checkpoint, mTORC1 signaling and E2F targets. Furthermore, the overexpression of DTL, and its association with immune cell infiltration and clinical indexes in liver hepatocellular carcinoma (LIHC), bladder urothelial carcinoma (BLCA) and stomach adenocarcinoma (STAD) were verified in our study. It was also verified that overexpression of DTL could regulate the cell cycle, promote cell proliferation and cause genomic instability in cultured cells, which may be the reason why DTL plays a role in the occurrence, progression and treatment of cancer. CONCLUSIONS: Collectively, this study suggested that DTL is of clinical value in the diagnosis, prognosis and treatment of various cancers, and may be a potential biomarker in certain cancers.

Improvement of irradiation-induced fibroblast damage by α2-macroglobulin through alleviating mitochondrial dysfunction.

CONTEXT: α2-Macroglobulin (α2-M) is believed to be a potential anti-irradiation agent, but related mechanisms remains unclear. OBJECTIVE: We investigated the irradiation protective effect of α2-M. MATERIALS AND METHODS: A total of 10 Gy dose of irradiation was used to damage human skin fibroblasts. The influence of α2-M (100 µg/mL) on the proliferation, migration, invasion and apoptosis of fibroblasts was observed using Cell Counting Kit-8 (CCK8), wound healing, transwell, and flow cytometry. Malondialdehyde, superoxide dismutase and catalase was measured using related ELISA kits. The levels of mitochondrial membrane potential and calcium were detected using flow cytometry. The expression of transient receptor potential melastatin 2 (TRPM2) was investigated through western blotting and immunofluorescence staining. RESULTS: High purity of α2-M was isolated from Cohn fraction IV. α2-M significantly increased cell proliferation, migration, invasion, but suppressed cell apoptosis after irradiation. The promotion of cell proliferation, migration and invasion by α2-M exceeded over 50% compared group irradiation. The increased cell ratio in the S phase and decreased cell ratio in the G2 phase induced by irradiation were remarkably reversed by α2-M. α2-M markedly suppressed the increased oxidative stress level caused by irradiation. The mitochondrial damage induced by irradiation was improved by α2-M through inhibiting mitochondrial membrane potential loss, calcium and TRPM2 expression. DISCUSSION AND CONCLUSIONS: α2-M significantly promoted the decreased fibroblast viability and improved the mitochondria dysfunction caused by irradiation. α2-M might present anti-radiation effect through alleviating mitochondrial dysfunction caused by irradiation. This study could provide a novel understanding about the improvement of α2-M on irradiation-induced injury.

Meta-Analysis of Risk Factors and Incidence of Interstitial Pneumonia With CHOP-Like Regimens for Non-Hodgkin Lymphoma.

Objectives: Interstitial pneumonitis (IP), a potentially fatal complication of non-Hodgkin Lymphoma (NHL) patients received CHOP (cyclophosphamide and doxorubicin and vincristine and prednisone)-like chemotherapy, negatively affected patients' clinical outcome and quality of life. We aimed to explore patient-related, disease-related and drug-related risk factors associated with IP and gain a better understanding of the incidence in NHL patients. Methods: Databases, including PubMed, Ovid, China National Knowledge Internet (CNKI), and Wanfang Database from inception to January 20, 2022, were searched to identify studies evaluating the risk factors and incidence of IP. The included studies were assessed by Newcastle-Ottawa Quality Scale and above 7 points was considered high quality. The statistical analysis of risk factors was assessed by RevMan software (version 5.3) and incidence of IP was calculated by R software (version 4.1.2). Fixed-or random-effects models were applied to estimated the relative risks (RRs) and 95% confidence interval (Cl). Results: A total of 12 studies comprised of 3423 NHL patients were included in the analysis. Among the 3 available patient-related risk factors, 6 disease-related risk factors and 3 drug-related risk factors, it was found that only drug-related risk factors were significantly associated with IP development: pegylated liposomes doxorubicin (PLD) replacement (RR = 3.25, 95% CI = 1.69-6.27, I2 = 64%), rituximab (RTX) addition (RR = 4.24, 95% CI = 2.58-6.96, I2 = 0) and granulocyte colony stimulating factor (G-CSF) administration (RR = 5.80, 95% CI = 3.05-11.05, I2 = 0). The pooled incidence of CHOP, R-CHOP, and R-CDOP regimen was 1.0% (95% CI 0.00-0.01, I2 = 8%), 7.0% (95% CI 0.05-0.09, I2 = 64%) and 22.0% (95% CI 0.13-0.32, I2 = 87%) respectively. Conclusion: PLD replacement, RTX addition and G-CSF administration were significant risk factors of IP for NHL patients received the CHOP-like chemotherapy. Clinicians should focus on these patients to detect and treat the IP development timely, which might bring benefit in patients' survival. Systematic Review Registration: PROSPERO, identifier CRD42022309884.

Cryotherapy for Prevention of Taxane-Induced Peripheral Neuropathy: A Meta-Analysis.

PURPOSE: Taxanes are widely used in gynecological cancer therapy, however, taxane-induced peripheral neuropathy (TIPN) limits chemotherapy dose and reduces patients' quality of life. As a safe and convenient intervention, cryotherapy has been recommended as a promising intervention in the recent clinical guidelines for the prevention of TIPN. Although there are a considerable number of studies which explored the use of cryotherapy in preventing chemotherapy-induced peripheral neuropathy (CIPN), there is insufficient large-scale clinical evidence. We performed a meta-analysis on the current available evidence to examine whether cryotherapy can prevent TIPN in cancer patients receiving taxanes. METHODS: We searched databases including PubMed, Embase, and Cochrane from inception to August 3, 2021 for eligible trials. Clinical trials that examined the efficacy of cryotherapy for prevention of TIPN were included. The primary outcome was the incidence of TIPN, and secondary outcomes were incidence of taxane dose reduction and changes in nerve conduction studies. The meta-analysis software (RevMan 5.3) was used to analyze the data. RESULTS: We analyzed 2250 patients from 9 trials. Assessments using the Common Terminology Criteria for Adverse Events (CTCAE) score showed that cryotherapy could significantly reduce the incidence of motor and sensory neuropathy of grade≥2 (sensory: RR 0.65, 95%CI 0.56 to 0.75, p<0.00001; motor: RR 0.18, 95% CI [0.03, 0.94], p=0.04). When evaluated using the Patient Neuropathy Questionnaire (PNQ), cryotherapy demonstrated significant reduction in the incidence of sensory neuropathy (RR 0.11, 95% CI 0.04 to 0.31], p<0.0001), but did not show significant reduction in the incidence of motor neuropathy (RR 0.46, 95% CI 0.11 to 1.88, p=0.28). Cryotherapy was associated with reduced incidences of taxane dose reduction due to TIPN (RR 0.48, 95% CI [0.24, 0.95], p=0.04) and had potential to preserve motor nerves. CONCLUSIONS: Cryotherapy is likely to prevent TIPN in patients receiving taxanes. High quality and sufficient amount of evidence is warranted.

Ectopic Expression of a Salt-Inducible Gene, LcSAIN3, from Sheepgrass Improves Seed Germination and Seedling Growth under Salt Stress in Arabidopsis.

Sheepgrass is a perennial native grass species in China, and it can tolerate high levels of salt stress with an aggressive and vigorous rhizome system. Many salt-stress-responsive genes have been identified in sheepgrass. In this study, we report the cloning and characterization of a novel salt-induced gene, LcSAIN3 (Leymus chinensis salt-induced 3), from sheepgrass. Expression analysis confirmed that LcSAIN3 was induced by PEG, ABA, and salt treatments, and the expression of LcSAIN3 was significantly increased in salt-tolerant germplasms under salt treatment. Subcellular localization analysis indicated that the GFP-LcSAIN3 protein was mainly localized in the chloroplasts. The heterologous expression of LcSAIN3 in Arabidopsis increased the seed germination rate of transgenic plants under salt, ABA, and mannitol treatments. The seedling survival rate, plant height, and fresh weight of the transgenic plants were higher than those of WT plants under salt stress. The overexpression of LcSAIN3 caused a relatively high accumulation of free proline, enhanced SOD activity, and led to the upregulation of several stress-responsive genes such as AtRD26, AtRD29B, AtSOS1, and AtP5CS1. These results suggest that LcSAIN3 could be a potential target for molecular breeding to improve plants' salt tolerance.

Screening and Identification of the First Non-CRISPR/Cas9-Treated Chinese Miniature Pig With Defective Porcine Endogenous Retrovirus pol Genes.

Pig to human xenotransplantation is considered to be a possible approach to alleviate the shortage of human allografts. Porcine endogenous retrovirus (PERV) is the most significant pathogen in xenotransplantation. We screened for pigs that consistently did not transmit human-tropic replication competent PERVs (HTRC PERVs), namely, non-transmitting pigs. Then, we conducted whole-genome resequencing and full-length transcriptome sequencing to further investigate the sequence characteristics of one non-transmitting pig. Using in vitro transmission assays, we found 5 (out of 105) pigs of the Chinese Wuzhishan minipig inbred line that did not transmit PERV to human cells, i.e., non-transmitting pigs. Whole-genome resequencing and full-length transcriptome sequencing of one non-transmitting pig showed that all of the pol genes were defective at both the genome and transcript levels. We speculate that the defective PERV pol genes in this pig might be attributable to the long-term inbreeding process. This discovery is promising for the development of a strain of highly homozygous and genetically stable pigs with defective PERV pol genes as a source animal species for xenotransplantation.

Identification of human parvovirus 4 genotypes 1 and 2 in Chinese source plasma pools.

Human parvovirus B19 (B19V) and human parvovirus 4 (PARV4) are known to infect humans and transmit through contaminated blood and blood products. Globally, three genotypes of B19V, as well as PARV4, have been identified, respectively. The existence of different B19V genotypes in Chinese plasma donors has been investigated, however, the data regarding PARV4 were not available. The main objective of this study is to identify the genotypes of PARV4 circulating in Chinese plasma donors. By using a duplex quantitative polymerase chain reaction assay adapted for all genotypes of B19V and PARV4, 78 source plasma pools for fractionation were screened and quantified. Results showed that positive rates of B19V and PARV4 DNA in plasma pool samples were 25.64% and 14.10%, respectively. PARV4 sequences in two positive samples were next genotyped, and these two sequences belonged to PARV4 genotypes 1 and 2, respectively. In conclusion, the data present demonstrate the existence of PARV4 genotypes 1 and 2 in Chinese plasma donors for the first time and also show the relatively lower prevalence and level of PARV4 DNA in Chinese plasma donors in comparison with that of B19V DNA.

LcMYB4, an unknown function transcription factor gene from sheepgrass, as a positive regulator of chilling and freezing tolerance in transgenic Arabidopsis.

BACKGROUND: Sheepgrass (Leymus chinensis (Trin.) Tzvel) is a perennial forage grass that can survive extreme freezing winters (- 47.5 °C) in China. In this study, we isolated an unknown function MYB transcription factor gene, LcMYB4, from sheepgrass. However, the function of LcMYB4 and its homologous genes has not been studied in other plants. RESULTS: The expression of the LcMYB4 gene was upregulated in response to cold induction, and the LcMYB4 fusion protein was localized in the nucleus, with transcriptional activation activity. Biological function analysis showed that compared with WT plants, LcMYB4-overexpressing Arabidopsis presented significantly increased chilling and freezing tolerance as evidenced by increased germination rate, survival rate, and seed setting rate under conditions of low temperature stress. Furthermore, LcMYB4-overexpressing plants showed increased soluble sugar content, leaf chlorophyll content and superoxide dismutase activity but decreased malondialdehyde (MDA) under chilling stress. Moreover, the expression of the CBF1, KIN1, KIN2 and RCI2A genes were significantly upregulated in transgenic plants with chilling treatment. These results suggest that LcMYB4 overexpression increased the soluble sugar content and cold-inducible gene expression and alleviated oxidative damage and membrane damage, resulting in enhanced cold resistance in transgenic plants. Interestingly, our results showed that the LcMYB4 protein interacts with fructose-1,6-bisphosphate aldolase protein1 (LcFBA1) and that the expression of the LcFBA1 gene was also upregulated during cold induction in sheepgrass, similar to LcMYB4. CONCLUSION: Our findings suggest that LcMYB4 encodes MYB transcription factor that plays a positive regulatory role in cold stress.

A MYB-related transcription factor from sheepgrass, LcMYB2, promotes seed germination and root growth under drought stress.

BACKGROUND: Drought is one of the most serious factors limiting plant growth and production. Sheepgrass can adapt well to various adverse conditions, including drought. However, during germination, sheepgrass young seedlings are sensitive to these adverse conditions. Therefore, the adaptability of seedlings is very important for plant survival, especially in plants that inhabit grasslands or the construction of artificial grassland. RESULTS: In this study, we found a sheepgrass MYB-related transcription factor, LcMYB2 that is up-regulated by drought stress and returns to a basal level after rewatering. The expression of LcMYB2 was mainly induced by osmotic stress and was localized to the nucleus. Furthermore, we demonstrate that LcMYB2 promoted seed germination and root growth under drought and ABA treatments. Additionally, we confirmed that LcMYB2 can regulate LcDREB2 expression in sheepgrass by binding to its promoter, and it activates the expression of the osmotic stress marker genes AtDREB2A, AtLEA14 and AtP5CS1 by directly binding to their promoters in transgenic Arabidopsis. CONCLUSIONS: Based on these results, we propose that LcMYB2 improves plant drought stress tolerance by increasing the accumulation of osmoprotectants and promoting root growth. Therefore, LcMYB2 plays pivotal roles in plant responses to drought stress and is an important candidate for genetic manipulation to create drought-resistant crops, especially during seed germination.

Transcriptomic Analysis Reveals a Comprehensive Calcium- and Phytohormone-Dominated Signaling Response in Leymus chinensis Self-Incompatibility.

Sheepgrass (Leymus chinensis (Trin.) Tzvel.) is an economically and ecologically important forage in the grass family. Self-incompatibility (SI) limits its seed production due to the low seed-setting rate after self-pollination. However, investigations into the molecular mechanisms of sheepgrass SI are lacking. Therefore, microscopic observation of pollen germination and pollen tube growth, as well as transcriptomic analyses of pistils after self- and cross-pollination, were performed. The results indicated that pollen tube growth was rapidly inhibited from 10 to 30 min after self-pollination and subsequently stopped but preceded normally after cross-pollination. Time course comparative transcriptomics revealed different transcriptome dynamics between self- and cross-pollination. A pool of SI-related signaling genes and pathways was generated, including genes related to calcium (Ca2+) signaling, protein phosphorylation, plant hormone, reactive oxygen species (ROS), nitric oxide (NO), cytoskeleton, and programmed cell death (PCD). A putative SI response molecular model in sheepgrass was presented. The model shows that SI may trigger a comprehensive calcium- and phytohormone-dominated signaling cascade and activate PCD, which may explain the rapid inhibition of self-pollen tube growth as observed by cytological analyses. These results provided new insight into the molecular mechanisms of sheepgrass (grass family) SI.

Comparative transcriptome analysis provides insights into the distinct germination in sheepgrass (Leymus chinensis) during seed development.

Sheepgrass (Leymus chinensis ((Trin.) Tzvel)) is an important perennial forage grass that is widely distributed in the Eurasia steppe. The seed germination percentage show significant variation among the different germplasm in sheepgrass. However, the underlying molecular mechanisms of distinct germination during seed development are still mostly unknown. Here, we performed comparative transcriptomic analyses of high seed germination percentage (H) and low seed germination percentage (L) at 14, 28, and 42 days after pollination. After comparing 3 consecutive development stages, 9255, 5366, and 4306 genes were found to be significantly differently expressed between H and L. Pathway analysis indicated that transcripts related to starch and sucrose metabolism, phenylpropanoid biosynthesis, plant hormone signal transduction, amino sugar and nucleotide sugar metabolism, and photosynthesis were significantly changed between the two germplasm at three stages. ABA and GA metabolism- and signaling transduction-related genes were differentially expressed between two germplasm at development stages, suggesting that the reduced signaling of GA and ABA is likely to be related to seed germination and dormancy in sheepgrass. We also identified 81 transcription factor (TF) families, and some TFs genes such as NAC48, NAC78, WRKY80, ZnFP, C3H14 and ILR3 were significantly differential expressed in two germplasm. Our results provide insights into seed development, germination and dormancy in sheepgrass at the transcriptional level.

bHLH92 from sheepgrass acts as a negative regulator of anthocyanin/proanthocyandin accumulation and influences seed dormancy.

LcbHLH92, a pleiotropic gene from sheepgrass, negatively regulates anthocyanins/proanthocyandins and reduces seed dormancy in transgenic Arabidopsis.

LcFIN2, a novel chloroplast protein gene from sheepgrass, enhances tolerance to low temperature in Arabidopsis and rice.

Adverse environmental stresses affect plant growth and crop yields. Sheepgrass (Leymus chinensis (Trin.) Tzvel), an important forage grass that is widely distributed in the east of Eurasia steppe, has high tolerance to extreme low temperature. Many genes that respond to cold stress were identified in sheepgrass by RNA-sequencing, but more detailed studies are needed to dissect the function of those genes. Here, we found that LcFIN2, a sheepgrass freezing-induced protein 2, encoded a chloroplast-targeted protein. Expression of LcFIN2 was upregulated by freezing, chilling, NaCl and abscisic acid (ABA) treatments. Overexpression of LcFIN2 enhanced the survival rate of transgenic Arabidopsis after freezing stress. Importantly, heterologous expression of LcFIN2 in rice exhibited not only higher survival rate but also accumulated various soluble substances and reduced membrane damage in rice under chilling stress. Furthermore, the chlorophyll content, the quantum photochemistry efficiency of photosystem II (ΦPSII), the non-photochemical quenching (NPQ), the net photosynthesis rate (Pn) and the expression of some chloroplast ribosomal-related and photosynthesis-related genes were higher in the transgenic rice under chilling stress. These findings suggested that the LcFIN2 gene could potentially be used to improve low-temperature tolerance in crops.

MADS-box family genes in sheepgrass and their involvement in abiotic stress responses.

BACKGROUND: MADS-box genes are categorized into A, B, C, D and E classes and are involved in floral organ identity and flowering. Sheepgrass (Leymus chinensis (Trin.) Tzvel) is an important perennial forage grass and adapts well to many adverse environments. However, there are few studies on the molecular mechanisms of flower development in sheepgrass, especially studies on MADS-domain proteins. RESULTS: In this study, we cloned 11 MADS-box genes from sheepgrass (Leymus chinensis (Trin.) Tzvel), and phylogenetic analysis of the 11 genes with their homologs revealed that they are divided into nine subclades. Tissue-specific expression profile analysis showed that most of these MADS-box genes were highly expressed in floral organs. LcMADS1 and LcMADS3 showed higher expression in the stamen than in the other tissues, and LcMADS7 showed high expression in the stamen, glume, lemma and palea, while expression of LcMADS2, LcMADS9 and LcMADS11 was higher in vegetative organs than floral organs. Furthermore, yeast two-hybrid analyses showed that LcMADS2 interacted with LcMADS7 and LcMADS9. LcMADS3 interacted with LcMADS4, LcMADS7 and LcMADS10, while LcMADS1 could interact with only LcMADS7. Interestingly, the expression of LcMADS1 and LcMADS2 were significantly induced by cold, and LcMADS9 was significantly up-regulated by NaCl. CONCLUSION: Hence, we proposed that LcMADS1, LcMADS2, LcMADS3, LcMADS7 and LcMADS9 play a pivotal role in sheepgrass sexual reproduction and may be involved in abiotic stress responses, and our findings provide useful information for further exploration of the functions of this gene family in rice, wheat and other graminaceous cereals.

Analysis of Protein Expression in Human Cells Cocultured with Porcine Peripheral Blood Mononuclear Cells.

OBJECTIVE: Porcine endogenous retroviruses (PERV) involved in pig to human xenotransplantation have raised great concerns because of their ubiquitous nature in pigs and their ability of infecting human cells in vitro. Although no significant cytopathic effect attributed to PERV was evident on PERV-infected human embryonic kidney 293 (HEK293) cells, we did proteomic analysis to investigate the differences of protein profile in order to further characterize the effect of PERV infection. METHODS: HEK293 cells were cocultured with porcine peripheral blood mononuclear cells (PBMCs). Protein profiles of PERV-infected and -noninfected HEK293 cells were analyzed by two-dimensional gel electrophoresis (2-DE). Protein spots with at least 1.5-fold alteration were identified by high-definition mass spectrometry (HDMS) analysis. Then real-time RT-PCR and Western blotting were performed to validate the proteomic results. RESULTS: Differential analysis of PERV-infected and -noninfected HEK293 cells by 2-DE revealed ten differentially regulated proteins. The proteins identified by HDMS were involved in various cellular pathways including signal transduction, cell apoptosis, and protein synthesis. CONCLUSION: The results of this study revealed differentially expressed proteins in HEK293 cells cocultured with porcine PBMCs and implied that these changes were probably induced by PERV infection. These results provide clues and potential links to understanding the molecular effect of the infection by human-tropic PERV.

Large-scale purification of high purity α1-antitrypsin from Cohn Fraction IV with virus inactivation by solvent/detergent and dry-heat treatment.

α1-Antitrypsin (AAT) is widely used to treat patients with congenital AAT deficiency. Cohn Fraction IV (Cohn F IV) is normally discarded during the manufacturing process of albumin but contains approximately 33% of plasma AAT. We established a new process for large-scale purification of AAT from it. liquid chromatography-electrospray ionization-tandem mass spectrometry and high-performance liquid chromatography were applied for qualitative identification and composition analysis, respectively. Stabilizers were optimized for AAT activity protection during lyophilization and dry-heat. Virus inactivation by dry-heat and solvent/detergent (S/D) was validated on a range of viruses. AAT with purity of 95.54%, specific activity of 3,938.5 IU/mg, and yield of 26.79%, was achieved. More than 95% activity was reserved after S/D. More than 96% activity was obtained after lyophilization or dry-heat. After S/D, pseudorabies virus (PRV) and vesicular stomatitis virus (VSV) were inactivated below detectable level within 1 H. Virus titer reductions of more than 5.50 log10 and 5.38 log10 were achieved for PRV and VSV, respectively. Porcine parvovirus and encephalomyocarditis virus were inactivated by 3.17 log10 and 5.88 log10 reduction after dry-heat. The advantages of this process, including suitability for large-scale production, high purity, better utilization of human plasma, viral safety, commercial and inexpensive chromatography medium, may facilitate its further application.

Simultaneous detection and differentiation of human parvovirus B19 and human parvovirus 4 by an internally controlled multiplex quantitative real-time PCR.

Human parvovirus B19 (B19V) and human parvovirus 4 (PARV4) are two parvoviruses known to infect humans and transmit through blood and plasma derived medicinal products (PDMPs). Inactivation of the two parvoviruses has proven to be difficult and nucleic acid testing (NAT) would be an efficient means to exclude viruses. In this study, an internally controlled multiplex quantitative real-time PCR (qPCR) assay for B19V and PARV4 simultaneous detection and quantification was established and evaluated. The optimized multiplex qPCR assay allowed for simultaneous detection of all of the genotypes (1-3) of B19V and PARV4, with equal limit of quantification (LOQ) of 5 copies/µL, rather than other blood-borne viruses. It had a wide dynamic range of reliable amplification linearity of at least 8 orders of magnitude. Low standard deviations (SD) of quantification cycle (Cq) values and low coefficients of variation (CV) of copy numbers for both B19V and PARV4 suggested a high level of repeatability and reproducibility for the multiplex qPCR assay. This multiplex qPCR assay can be served as a readily applicable approach to screen plasma units intended for further manufacturing into PDMPs to reduce the risk of parvoviruses infection by such products and may also be useful for the detection of B19V/PARV4 co-infection or co-existence.