Extensive epigenetic reprogramming involves in memory CD8+ T-cell differentiation. The elaborate epigenetic rewiring underlying the heterogeneous functional states of CD8+ T cells remains hidden. Here, we profile single-cell chromatin accessibility and map enhancer-promoter interactomes to characterize the differentiation trajectory of memory CD8+ T cells. We reveal that under distinct epigenetic regulations, the early activated CD8+ T cells divergently originated for short-lived effector and memory precursor effector cells. We also uncover a defined epigenetic rewiring leading to the conversion from effector memory to central memory cells during memory formation. Additionally, we illustrate chromatin regulatory mechanisms underlying long-lasting versus transient transcription regulation during memory differentiation. Finally, we confirm the essential roles of Sox4 and Nrf2 in developing memory precursor effector and effector memory cells, respectively, and validate cell state-specific enhancers in regulating Il7r using CRISPR-Cas9. Our data pave the way for understanding the mechanism underlying epigenetic memory formation in CD8+ T-cell differentiation.
CD8-Positive T-Lymphocytes/metabolism* ; Cell Differentiation ; Chromatin/immunology* ; Animals ; Mice ; Immunologic Memory ; Epigenesis, Genetic ; SOXC Transcription Factors/immunology* ; NF-E2-Related Factor 2/immunology* ; Mice, Inbred C57BL ; Gene Regulatory Networks ; Enhancer Elements, Genetic

ObjectiveTo explore the effects of Naozhenning granules on the memory function and neuron cells in the rat model of post-concussion syndrome based on mitochondrial biosynthesis. MethodSPF-grade Wistar rats were used to establish the multiple cerebral concussion （MCC） model by the weight-drop method. The successfully modeled rats were assigned into model， piracetam （0.324 g·kg^-1）， and low-， medium-， and high-dose （2.25， 4.5， and 9 g·kg^-1， respectively） Naozhenning groups. The rats were administrated with corresponding drugs by gavage and those in the blank group and model group were administrated the same volume of normal saline once a day for 14 days. The general state of rats was observed before and after treatment. The open field test and new object recognition test were conducted to examine the motor and memory abilities of rats. Hematoxylin-eosin staining was employed to observe the pathological changes of cortical neurons in rats. Western blot and real-time polymerase chain reaction were employed to determine the protein and mRNA levels， respectively， of peroxisome proliferator-activated receptor γ-coactivator-1α （PGC-1α）， nuclear respiratory factor-1 （NRF-1）， and transcription factor A mitochondrial （TFAM） in rat cortex. ResultCompared with the blank group， the model group showed anxious and manic mental status， yellow and messy fur， and reduced food intake. In the open field experiment， the model group showed reduced total movement distance， times of entering the central grid， and times of rearing decreased and increased resting time compared with the blank group （P<0.01）. The model group had lower recognition index of new objects than the blank group （P<0.01）. In addition， the modeling caused reduced neurons with sparse distribution and deformed， broken， and irregular nucleoli and down-regulated the mRNA and protein levels of PGC-1α， NRF-1， and TFAM in the cortex （P<0.01）. Compared with the model group， piracetam and Naozhenning improved the mental state， coat color， food intake， and activities of rats. In the open field test， piracetam and Naozhenning increased the total movement distance， the times of entering the central grid， and the times of rearing and shortened the resting time （P<0.05， P<0.01）. The piracetam and Naozhenning groups had higher recognition index of new objects than the model group （P<0.05， P<0.01）. Compared with the model group， the piracetam and Naozhenning groups showed increased neurons with tight arrangement and large and round nuclei， and some cells with irregular morphology and turbid cytoplasm. Furthermore， piracetam and medium-dose Naozhenning upregulated the protein levels of PGC-1α， NRF-1， and TFAM （P<0.01）. Low-dose Naozhenning upregulated the protein levels of NRF-1 and TFAM （P<0.01）， and high-dose Naozhenning upregulated the protein levels of PGC-1α and TFAM in the cortex （P<0.01）. The mRNA levels of PGC-1α， NRF-1， and TFAM in the cortex were upregulated in the piracetam group and Naozhenning groups （P<0.05， P<0.01）. ConclusionNaozhenning granules can improve the motor， memory， and learning， repair the neuronal damage， and protect the nerve function in the rat model of MCC by promoting mitochondrial biosynthesis.

Glucosyltransferases (Gtfs) play critical roles in the etiology and pathogenesis of Streptococcus mutans (S. mutans)- mediated dental caries including early childhood caries. Gtfs enhance the biofilm formation and promotes colonization of cariogenic bacteria by generating biofilm extracellular polysaccharides (EPSs), the key virulence property in the cariogenic process. Therefore, Gtfs have become an appealing target for effective therapeutic interventions that inhibit cariogenic biofilms. Importantly, targeting Gtfs selectively impairs the S. mutans virulence without affecting S. mutans existence or the existence of other species in the oral cavity. Over the past decade, numerous Gtfs inhibitory molecules have been identified, mainly including natural and synthetic compounds and their derivatives, antibodies, and metal ions. These therapeutic agents exert their inhibitory role in inhibiting the expression gtf genes and the activities and secretion of Gtfs enzymes with a wide range of sensitivity and effectiveness. Understanding molecular mechanisms of inhibiting Gtfs will contribute to instructing drug combination strategies, which is more effective for inhibiting Gtfs than one drug or class of drugs. This review highlights our current understanding of Gtfs activities and their potential utility, and discusses challenges and opportunities for future exploration of Gtfs as a therapeutic target.
Biofilms ; Dental Caries/prevention & control* ; Glucosyltransferases/antagonists & inhibitors* ; Humans ; Streptococcus mutans/enzymology*

OBJECTIVETo assess the association of programmed cell death 1 (PDCD1) gene polymorphisms with the susceptibility and/or progression of colorectal cancer.

METHODSA hospital-based case-control study was carried out, which recruited 426 colorectal cancer patients and 500 healthy individuals. Five single nucleotide polymorphisms, namely rs36084323, rs11568821, rs2227981, rs2227982 and rs10204525, were selected for the study and genotyped with a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.

RESULTSThe G allele of rs36084323 under a dominant model was associated with increased risk of advanced TNM staging of colorectal cancer progression (OR=1.59, 95%CI=1.02-2.48). Haplotypes G-G-C-T-A and A-G-C-C-G of the rs36084323, rs11568821, rs2227981, rs2227982, and rs10204525 were negatively associated with the occurrence of colorectal cancer.

CONCLUSIONThe G allele of rs36084323 is associated with increased risk of advanced TNM staging of colorectal cancer. Conversely, the incidence of colorectal cancer is negatively associated with the haplotypes G-G-C-T-A and A-G-C-C-G of rs36084323, rs11568821, rs2227981, rs2227982, and rs10204525.

Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; China ; ethnology ; Colorectal Neoplasms ; genetics ; pathology ; Genetic Predisposition to Disease ; Haplotypes ; Humans ; Neoplasm Staging ; Polymorphism, Single Nucleotide ; Programmed Cell Death 1 Receptor ; genetics

OBJECTIVETo investigate the protective effect of bone marrow mesenchymal stem cells (BMSCs)-derived exosomesagainst testicular ischemia-reperfusion injury (IRI) in rats.

METHODSRat BMSCs were isolated, cultured and identified in theprimary culture. The exosomes were extracted from the BMSCs and characterized using nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. Twenty-four healthy male SD rats were randomly divided into shamoperation group, testicular IRI with saline treatment group and IRI with exosome treatment group. The contralateral testes ofthe rats were collected for pathological observation, aseessment of superoxide dismutase (SOD) and malondialdehyde (MDA), and detection of HMGB1, caspases-3 and cleaved caspase-3 expressions using Western blotting.

RESULTSWe successfullyobtained exosomes from rat BMSCs. Testicular IRI significantly impaired testicular spermatogenesis, which was markedlyimproved by treatment with the exosomes ( < 0.05). Testicular IRI also caused significant increase in the protein expression ofHMGB1, caspase-3 and cleaved caspase-3 in the testicular tissue, and treatment with the exosomes obviously amelioratedthese changes ( < 0.05).

CONCLUSIONSBMSCs-derived exosomes protects against testicular IRI due to the anti-oxidant, antiinflammatory and anti-apoptosis activities of the exosomes.

Objective To explore the effect of Ginkgo biloba extract (EGb761) on apoptosis of K-ras mutational human colon cancer cells DLD1(DLD1/G13D)and its mechanism. Methods Human colon cancer cell lines DLD1/G13D and DLD1 with K-ras wild type(DLD1/WT)were cultured in vitro,the cell proliferation and apoptosis after 24 h of EGb761 were measured. Proteins involved in related signal pathway were detected by Western blot or ELISA. Results EGb761 reduced cell proliferation and induced cell apoptosis in a concentration-dependent manner in DLD1/WT and DLD1/G13D cells. EGb761 downregulated the expression of RIP1, impaired the phosphorylation of IκB and decreased the level of NF-κB in DLD1/WT and DLD1/G13D cells[DLD1/G13D: (24±4)%, DLD1/WT: (29±9)%(P<0.05). Conclusion EGb761 restrains the proliferation and induces the apoptosis of DLD1/WT and DLD1/G13D cells. The mechanism may be related to the degradation of RIP-1 and inhibition of activation of NF-κB signaling pathway.

Aptamers are capable of binding a wide range of biomolecular targets with high affinity and specificity. It has been widely developed for diagnostic and therapeutic purposes. Because of unique three dimensional structures and cell-membrane penetration, aptamers inhibit virus infection not only through binding specific target, such as the viral envelope, genomic site, enzyme, or other viral components, but also can be connected to each other or with siRNA jointly achieve antiviral activity. Taking human immunodeficiency virus and hepatitis C virus as examples, this paper reviewed the effects and mechanisms of aptamers on disturbing viral infection and replication steps. It may provide an insight to the development of aptamer-based new antiviral drugs.

High mobility group A2 protein (HMGA2), an architectural factor, is highly expressed in various cancer types including lung cancers. It is a candidate target for cancer therapy. RNAi is an effective gene silencing method with low cost and less time-consuming. It is possible to exploit this technology in therapy. Here, 5 siRNAs targeting Hmga2 gene (HMGA2 siRNA1-5) were designed and synthesized. MTT assay, colony formation assay, transwell assay and flow cytometry were used to evaluate the effects of these siRNAs on lung cancer cell lines (NCI-H446 and A549). Results from cell proliferation, clone formation, migration and apoptosis showed that HMGA2 siRNA1, 3, 5 could affect these aspects for both lung cancer cell lines. Among the five siRNAs, HMGA2 siRNA5 showed the greatest inhibition effects. The inhibition effects of HMGA2 siRNA5 are sequence specific and are not due to the induction of interferon response. Taken together, siRNAs targeting Hmga2 gene are potential candidates for lung cancer gene therapy.

The aim of this study was to reveal the protection role and the related mechanism of cytoglobin on the oxidation induced hepatic stellate cell damage. We applied siRNA to interfere the endogenous cytoglobin gene, used recombinant cytoglobin protein to treat the completely activated human hepatic stellate cell line LX-2 and the incompletely activated primary rat hepatic stellate cells, or over-expressed cytoglobin protein in LX-2 cells. We used two different oxidative-stress related models, the hydrogen peroxide model and the iron-overload model in our experiments and investigated the proliferation status and the intracellular superoxide level of the cells. The results showed that endogenous cytoglobin exerted significant protective effects on hydrogen peroxide or iron-overload induced LX-2 cell damage, confirming that upregulation of cytoglobin was the protective response of activated hepatic stellate cells to oxidative stress. Recombinant cytoglobin protein could protect LX-2 cells from oxidation induced damage, and prevent primary rat hepatic stellate cells from excessive proliferation and injury. The cytoplasmic reactive oxygen species (ROS) scavenging capacity of the recombinant cytoglobin protein was not as good as its capacity in scavenging ROS outside the cells, likely owing to the lack of active transporting mechanisms. Intracellular over-expression of cytoglobin protein could exert significant protective effect on LX-2 cells treated with hydrogen peroxide or iron-overload. Our results would accelerate the exploitation of new anti-fibrotic targets.
Animals ; Cell Line ; Globins ; genetics ; pharmacology ; Hepatic Stellate Cells ; cytology ; pathology ; Humans ; Hydrogen Peroxide ; toxicity ; Oxidative Stress ; drug effects ; Protective Agents ; pharmacology ; RNA, Small Interfering ; genetics ; Rats ; Reactive Oxygen Species ; metabolism

Recombinant adeno-associated viral vectors (rAAV) have been widely used as gene therapy vectors in clinical trials. Here, we reviewed the genomic structures and replication mechanisms of wt-AAV. Then, the assembly of capsid and the encapsidation of genomic DNA, two major events during AAV pakaging, was discussed in detail. Although the overall pattern of virus assembly and encapsidation is known, the molecular mechanisms and the structure-function relationship involved in these processes are not well understood. Further elucidatation of these processes may improve the production technology of rAAV and develop gene drug based on rAAV.
Capsid ; physiology ; Capsid Proteins ; genetics ; DNA, Viral ; genetics ; Dependovirus ; genetics ; physiology ; Genetic Vectors ; Genome, Viral ; Virus Assembly ; genetics ; physiology