Progress,implications,and challenges in using humanized immune system mice in CAR-T therapy-Application evaluation and improvement

In recent years,humanized immune system(HIS)mice have been gradually used as models for preclinical research in pharmacotherapies and cell therapies with major breakthroughs in tumor and other fields,better mimicking the human immune system and the tumor immune microenvironment,compared to traditional immunodeficient mice.To better promote the application of HIS mice in preclinical research,we se-lectively summarize the current prevalent and breakthrough research and evaluation of chimeric antigen receptor(CAR)-T cells in various antiviral and antitumor treat-ments.By exploring its application in preclinical research,we find that it can better reflect the actual clinical patient condition,with the advantages of providing high-efficiency detection indicators,even for progressive research and development.We believe that it has better clinical patient simulation and promotion for the updated design of CAR-T cell therapy than directly transplanted immunodeficient mice.The characteristics of the main models are proposed to improve the use defects of the existing models by reducing the limitation of antihost reaction,combining multiple models,and unifying sources and organoid substitution.Strategy study of relapse and toxicity after CAR-T treatment also provides more possibilities for application and development.

Comparison of the replication and neutralization of different SARS-CoV-2 Omicron subvariants in vitro

Background:New Omicron subvariants are emerging rapidly from BA.1 to BA.4 and BA.5.Their pathogenicity has changed from that of wild-type(WH-09)and Omicron variants have over time become globally dominant.The spike proteins of BA.4 and BA.5 that serve as the target for vaccine-induced neutralizing antibodies have also changed compared to the previous subvariants,which is likely to cause immune es-cape and the reduction of the protective effect of the vaccine.Our study addresses the above issues and provides a basis for formulating relevant prevention and control strategies.Methods:We collected cellular supernatant and cell lysates and measured the viral titers,viral RNA loads,and E subgenomic RNA(E sgRNA)loads in different Omicron subvariants grown in Vero E6 cells,using WH-09 and Delta variants as a reference.Additionally,we evaluated the in vitro neutralizing activity of different Omicron sub-variants and compared it to the WH-09 and Delta variants using macaque sera with different types of immunity.Results:As the SARS-CoV-2 evolved into Omicron BA.1,the replication ability in vitro began to decrease.Then with the emergence of new subvariants,the replication ability gradually recovered and became stable in the BA.4 and BA.5 subvariants.In WH-09-inactivated vaccine sera,geometric mean titers of neutralization antibodies against different Omicron subvariants declined by 3.7~15.4-fold compared to those against WH-09.In Delta-inactivated vaccine sera,geometric mean titers of neutrali-zation antibodies against Omicron subvariants declined by 3.1~7.4-fold compared to those against Delta.Conclusion:According to the findings of this research,the replication efficiency of all Omicron subvariants declined compared with WH-09 and Delta variants,and was lower in BA.1 than in other Omicron subvariants.After two doses of inactivated(WH-09 or Delta)vaccine,cross-neutralizing activities against various Omicron subvariants were seen despite a decline in neutralizing titers.

Sequentially immune-induced antibodies could cross-neutralize SARS-CoV-2 variants

Background:The Omicron(B.1.1.529)SARS-COV-2 variant has raised serious concerns because of its unprecedented rapid rate of spreading and the fact that there are 36 mutations in the spike protein.Since the vaccine-induced neutralizing antibody targets are the spike protein,this may lead to the possibility of vaccine-induced hu-moral immunity escape.Methods:We measured the neutralizing activity in vitro for Omicron and compared this with wild type(WH-09)and Delta variants in human and monkey sera from different types of immunity.The monkey sera samples were collected at 1 and 3 months post three-dose inactivated(PiCoVacc)and recombinant protein(ZF2001)vaccination.Human sera were collected from 1 month post three-dose inactivated vaccination.Results:In inactivated vaccine sera,at 1/3 months post three-dose,geometric mean titers(GMTs)of neutralization antibody(NAb)against the Omicron variant were 4.9/5.2-fold lower than those of the wild type.In recombinant protein vaccine sera,GMTs of NAb against Omicron were 15.7/8.9-fold lower than those of the wild type.In human sera,at 1 month post three-dose inactivated vaccination,GMTs of NAb against Omicron were 3.1-fold lower than those of the wild type.Conclusion:This study demonstrated that despite a reduction in neutralization titers,cross-neutralizing activity against Omicron and Delta variants was still observed after three doses of inactivated and recombinant protein vaccination.

Evaluating the Health Risks of Pneumonia from Airborne Bacterial Communities Using 16S rDNA Sequences of Pneumonia-related Pathogens

Objective Airborne microbial communities include a significant number of uncultured and poorly characterized bacteria.No effective method currently exists to evaluate the health risks of such complex bacterial populations,particularly for pneumonia.Methods We developed a method to evaluate risks from airborne microorganisms,guided by the principle that closer evolutionary relationships reflect similar biological characteristics,and thus used16 S rDNA sequences of 10 common pneumonia-related bacterial pathogens.We calculated a risk of breath-related(Rbr)index of airborne bacterial communities and verified effectiveness with artificial flora and a clinical project.Results We suggested applying Rbr80 to evaluate the health risks of airborne bacterial communities that comprise 80% of dominant operational taxonomic units(OTUs).The feasibility of Rbr80 was confirmed by artificial flora and by pneumonia data from a hospital.A high Rbr80 value indicated a high risk of pneumonia from airborne bacterial communities.Conclusion Rbr80 is an effective index to evaluate the pneumonia-associated risk from airborne bacteria.Values of Rbr80 greater than 15.40 are considered high risk.

Distinct neuronal excitability alterations of medial prefrontal cortex in early-life neglect model of rats

Object:Early-life neglect has irreversible emotional effects on the central nervous system.In this work,we aimed to elucidate distinct functional neural changes in me-dial prefrontal cortex(mPFC)of model rats.Methods:Maternal separation with early weaning was used as a rat model of early-life neglect.The excitation of glutamatergic and GABAergic neurons in rat mPFC was recorded and analyzed by whole-cell patch clamp.Results:Glutamatergic and GABAergic neurons of mPFC were distinguished by typi-cal electrophysiological properties.The excitation of mPFC glutamatergic neurons was significantly increased in male groups,while the excitation of mPFC GABAergic neurons was significant in both female and male groups,but mainly in terms of rest membrane potential and amplitude,respectively.Conclusions:Glutamatergic and GABAergic neurons in medial prefrontal cortex showed different excitability changes in a rat model of early-life neglect,which can contribute to distinct mechanisms for emotional and cognitive manifestations.

Combined superposition effect of hypertension and dyslipidemia on left ventricular hypertrophy

Background : Hypertension and dyslipidemia are considered reversible risk factors for cardiovascular disease. The purpose of this study was to explore the impact of traditional and nontraditional blood lipid profiles on the risk of left ventricular hypertrophy(LVH) and to explore the superposition effect of dyslipidemia combined with hypertension.Methods : Data on 9134 participants(53.5 ±10.3 years old) from the Northeast China Rural Cardiovascular Health Study(NCRCHS) were statistically analyzed. The blood lipid profile was measured by total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), high-density lipoprotein cholesterol(HDL-C), total glyceride(TG), and calculated nontraditional blood lipid indices including non-HDL-C, atherosclerosis index(AI), TC/HDL-C, and residual cholesterol(RC).Results : After the adjustment of age and gender, the odds ratios(ORs) of LVH in patients with hypertension, high LDL-C, high non-HDL-C, high AI, and high TC/HDL-C were 3.97(3.31– 4.76), 1.27(1.02– 1.59), 1.21(1.04– 1.39), 1.33(1.15– 1.53), and 1.42(1.22– 1.65), respectively. After full adjustment of potential confounding factors, high AI and TC/HDL-C were associated with LVH rather than traditional blood lipid indices.The combination of hypertension and nontraditional dyslipidemia(defined by high AI and TC/HDL-C) was associated with the highest risk of LVH, especially in participants under 45 years of age. The risk was more significant in men, 5.09-fold and 6.24-fold,respectively, compared with 3.66-fold and 4.01-fold in women.Conclusions : People with dyslipidemia defined by nontraditional blood lipid indices(high AI and high TC/HDL-C) and hypertension were more likely to develop LVH.

Dihydroartemisinin ameliorates palmitate-induced apoptosis in cardiomyocytes via regulation on miR-133b/Sirt1 axis

Excessive fat ectopically deposited in the non-adipose tissues is considered as one of the leading causes of myopathy.The aim of this study was to investigate the role of Dihydroartemisinin(DHA)in palmitate(PAL)-incubated H9c2 cells(lipotoxicity-induced cell injury model).Cell viability of PAL-treated cells was determined by MTT assay,and apoptotic regulators were examined by qRT-PCR and western blot analysis,in the absence or in the presence of DHA,respectively.Expression levels of miR-133b and Sirt1 were also evaluated by qRT-PCR and western blotting examination.PAL decreased the viability of H9c2 cells and enhanced the expression of apoptotic genes.DHA reversed the effect of PAL on cell viability and lowed the level of Caspase3 and Bax.It also lowered the expression of miR-133b,while enhanced the expression of Bcl-2.Sirt1 was revealed as target of miR-133b through transcriptional regulation and the process was affected by DHA.DHA partially protected against the PAL-induced lipotoxicity by influencing the expression of miR-133b that hindered the activity of Sirt1.DHA may be used as a potential treatment in clinical management for lipotoxicity induced heart complications.

Characteristics of animal models for COVID-19

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the causative agent of coronavirus disease 2019(COVID-19),the most consequential pandemic of this century,threatening human health and public safety.SARS-CoV-2 has been continuously evolving through mutation of its genome and variants of concern have emerged.The World Health Organization R&D Blueprint plan convened a range of expert groups to develop animal models for COVID-19,a core requirement for the prevention and control of SARS-CoV-2 pandemic.The animal model construction techniques developed during the SARS-CoV and MERS-CoV pandemics were rapidly deployed and applied in the establishment of COVID-19 animal models.To date,a large number of animal models for COVID-19,including mice,hamsters,minks and nonhuman primates,have been established.Infectious diseases produce unique mani-festations according to the characteristics of the pathogen and modes of infection.Here we classified animal model resources around the infection route of SARS-CoV-2,and summarized the characteristics of the animal models constructed via transnasal,localized,and simulated transmission routes of infection.

Canine on the Couch:The New Canary in the Coal Mine for Environmental Health Research

Human health is intimately connected and tied to the health of our environment and ecosystem,with only a very small fraction of the risk for chronic diseases explained by genetics alone.Companion animals are prone to disease types that are shared with people,including cancers and endocrine disorders,reinforcing the thought that environmental factors contribute to the risks for chronic diseases.These factors include air and water pollution and the built environment.As such,there is increasing interest in pursuing research with companion animals,and specifically dogs,as sentinel species to inform comparative health assessments and identify risk factors for disease.Of the canine diseases for which environmental exposure research has been published,cancers have received the most attention.This review summarizes two main aspects of this comparative approach:(1)cancers that occur in dogs and which are similar to humans and(2)research investigating environmental exposures and health outcomes in dogs.The goal of this review is to highlight the diverse conditions in which pet dogs may provide unique perspectives and advantages to examine relationships between environmental exposures and health outcomes,with an emphasis on chemical pollution and cancer.Furthermore,this review seeks to raise awareness and stimulate discussion around the best practices for the use of companion animals as environmental health sentinels.

Dynamic Changes of the Infralimbic Cortex and Its Regulation of the Prelimbic Cortex in Rats with Chronic Inflammatory Pain

The prelimbic cortex(PL)is actively engaged in pain modulation.The infralimbic cortex(IL)has been reported to regulate the PL.However,how this regulation affects pain remains unclear.In the present study,we recorded temporary hyper-activity of PL pyramidal neurons responding to nociceptive stimuli,but a temporary hypofunction of the IL by in vivo electrophysiological recording in rats with peripheral inflammation.Manipulation of the PL or IL had opposite effects on thermal hyperalgesia.Furthermore,the functional connectivity and chemogenetic regulation between the subregions indicated an inhibitory influence of the IL on the PL.Activation of the pathway from the IL to the PL alleviated thermal hyperalgesia,whereas its inhibition exacerbated chronic pain.Overall,our results suggest a new mechanism underlying the role of the medial prefrontal cortex in chronic pain:hypo-function of the IL leads to hyperactivity of the PL,which regulates thermal hyperalgesia,and thus contributes to the chronicity of pain.

Advances in biomaterials and regenerative medicine for primary ovarian insufficiency therapy

Primary ovarian insufficiency(POI)is an ovarian dysfunction that affects more than 1%of women and is characterized by hormone imbalances that afflict women before the age of 40.The typical perimenopausal symptoms result from abnormal levels of sex hormones,especially estrogen.The most prevalent treatment is hormone replacement therapy(HRT),which can relieve symptoms and improve quality of life.However,HRT cannot restore ovarian functions,including secretion,ovulation,and fertility.Recently,as part of a developing field of regenerative medicine,stem cell therapy has been proposed for the treatment of POI.Thus,we recapitulate the literature focusing on the use of stem cells and biomaterials for POI treatment,and sum up the underlying mechanisms of action.A thorough understanding of the work already done can aid in the development of guidelines for future translational applications and clinical trials that aim to cure POI by using regenerative medicine and biomedical engineering strategies.

Cell and biomaterial-based approaches to uterus regeneration

Asherman’s syndrome(AS)is an endometrial disorder in which intrauterine adhesions crowd the uterine cavity and wall.The fibrotic adhesions are primarily the result of invasive uterine procedures that usually involve the insertion of surgical equipment into the uterus.This syndrome is accompanied by a number of clinical manifestations,including irregular or painful menstruation and infertility.The most prevalent treatment is hysteroscopy,which involves the physical removal of the fibrous strands.Within the last decade,however,the field has been exploring the use of cellbased therapeutics,in conjunction with biomaterials,to treat AS.This review is a recapitulation of the literature focused on cellular therapies for treating AS.

In vivo real-time imaging of gemcitabine-leaded growth inhibition in the orthotopic transplantation model of human pancreatic tumor

Human xenograft mouse models,which have been used in cancer research for over a century,provided significant advances for our understanding of this multifaceted family of diseases.Orthotopic transplantation tumor models are emerging as the preference for cancer research due to the increasing clinical relevance over subcutaneous mouse models.In this study,a stable luciferaseexpressed Capan-2 cell line was constructed and the expression of luciferase was tested.The results showed that the luminorescence intensity of Capan-2^(Luc) cells was associated with the number of cells and the minimal detectable cell population was 600 cells/well.We established an orthotopic transplantation model of pancreatic cancer using Capan-2^(Luc) cell line in athymic mice and investigated the inhibitory effects of gemcitabine(Gem)in vitro and in vivo.Optical imaging system was applied to evaluate the tumor growth of orthotopic transplantation model in vivo.The results suggested that the orthotopic transplantation model of pancreatic cancer was well established and the luminorescence intensity of Gem-treated group was markedly lower than that of control group with an inhibitory rate of 56.8%(P<0.001).Our orthotopic transplantation model of pancreatic cancer and real-time imaging observation method established in this study could be an ideal model and a useful tool for therapeutic approaches for pancreatic cancers.

Sequential infection with H1N1 and SARS-CoV-2 aggravated COVID-19 pathogenesis in a mammalian model, and covaccination as an effective method of prevention of COVID-19 and influenza

Influenza A virus may circulate simultaneously with the SARS-CoV-2 virus,leading to more serious respiratory diseases during this winter.However,the influence of these viruses on disease outcome when both influenza A and SARS-CoV-2 are present in the host remains unclear.Using a mammalian model,sequential infection was performed in ferrets and in K18-MCE2 mice,with SARS-CoV-2 infection following H1N1.We found that co-infection with H1N1 and SARS-CoV-2 extended the duration of clinical manifestation of COVID-19,and enhanced pulmonary damage,but reduced viral shedding of throat swabs and viral loads in the lungs of ferrets.Moreover,mortality was increased in sequentially infected mice compared with single-infection mice.Compared with singlevaccine inoculation,co-inoculation of PiCoVacc(a SARS-CoV-2 vaccine)and the flu vaccine showed no significant differences in neutralizing antibody titers or virus-specific immune responses.Combined immunization effectively protected K18-MCE2 mice against both H1N1 and SARS-CoV-2 infection.Our findings indicated the development of systematic models of co-infection of H1N1 and SARS-CoV-2,which together notably enhanced pneumonia in ferrets and mice,as well as demonstrated that simultaneous vaccination against HINT and SARS-CoV-2 may be an effective prevention strategy for the coming winter.

Sequential immunizations confer cross-protection against variants of SARS-CoV-2,including Omicron in Rhesus macaques

Variants of concern(VOCs)like Delta and Omicron,harbor a high number of mutations,which aid these viruses in escaping a majority of known SARS-CoV-2 neutralizing antibodies(NAbs).In this study,Rhesus macaques immunized with 2-dose inactivated vaccines(Coronavac)were boosted with an additional dose of homologous vaccine or an RBD-subunit vaccine,or a bivalent inactivated vaccine(Beta and Delta)to determine the effectiveness of sequential immunization.The booster vaccination significantly enhanced the duration and levels of neutralizing antibody titers against wild-type.

Light-triggered NO-releasing nanoparticles for treating mice with liver fibrosis

Liver fibrosis, resulting from chronic liver damage and characterized by the accumulation of extracellular matrix (ECM) proteins, is a characteristic of most types of chronic liver diseases. The activation of hepatic stellate cells (HSC) is considered an essential pathological hallmark in liver fibrosis. Although nitric oxide (NO) can effectively induce HSC apoptosis, the systemic administration of NO is ineffective and may cause severe complications such as hypotension. To overcome this limitation, nanoparticles were designed to target HSCs and release NO locally under the exposure of near infrared light (NIR). To achieve this, upconversion nanoparticle (UCNP) cores were enveloped in mesoporous silica shells (UCNP@mSiO2), which were modified with hyaluronic acid (HA-UCNP@mSiO2) and Roussin’s black salt (RBS). HA molecules recognize and bind to CD44 proteins, which are overexpressed on activated HSCs. Under exposure to a 980-nm NIR laser, the UCNP cores convert the 980-nm wavelength into ultraviolet (UV) light, which then energizes the RBS (NO donors), resulting in an efficient release of NO inside of the HSCs. Once released, NO triggers HSC apoptosis and reverses the liver fibrosis. This targeted and controlled release method provides the theoretical and experimental basis for novel therapeutic approaches to treat hepatic fibrosis.

Construction of cholecystokinin transgenic mouse and its effects on food intake

Background Cholecystokinin （CCK） is one of the richest neuropeptides in the mammalian brain, which is mainly distributed in the cerebral cortex, hippocampus, thalamus and caudate-putamen. CCK is implicated in a variety of behavioral functions such as food intake, learning, memory, anxiety, pain and neuroprotection. The current research results for CCK are obtained mainly through injection of CCK peptide into the body. The key issues of whether CCK can regulate diet by a central pathway and whether there are long-term regulation effects on diet are still unresolved. In this study, the effects of CCK on food intake in transgenic mice were investigated. Methods Transgenic mice were created by microinjection of the PDGF-CCK construct into male pronucleus of the zygotes. The genomic phonetype of transgenic mice were identified by PCR. The expression of PDGF-CCK was analyzed by Western blotting. Body weight, plasma glucose, cholesterol and triglycerides were assayed and analyzed. Results Two PDGF-CCK transgenic independent lines were established and exhibited a high-levels brain-specific transgene expression compared with that of nontransgenic littermate controls. The food intake of male CCK transgenic mice was decreased by 5%-10% with the same levels of water consumed compared with wild type mice. The food intake in female mice was not obviously changed. In the transgenic mice the bodyweight was lower and plasma glucose was higher compared with the nontransgenic littermate controls. Conclusions The high expression of the CCK gene in the brain can decrease body weight and increase plasma glucose. The differences in food intake between the males and females require further study. Chin Med J 2009; 122（17）：2022-2026

Structural and functional analysis of a potent human neutralizing antibody against enterovirus A71

Enterovirus A71(EV-A71) causes major outbreaks of hand,foot,and mouth disease(HFMD) in many countries,most frequently affecting children,and a small proportion of cases may lead to death.Currently,no vaccine is available in most endemic regions,and no licenced treatments for EV-A71 infection are available.Here,we characterize a human monoclonal antibody(Hu MAb),E1,by screening a Fab antibody phage library derived from patients who recovered from EV-A71 infection.E1 exhibits strong neutralizing activity against EV-A71 virus in cells.The cryo-electron microscopy(cryo-EM) structures of the EV-A71 virion in complex with E1 Fab fragments demonstrated that E1 recognized an epitope formed by residues in the BC and HI loops of VP1.In a mouse model,E1 effectively protected against lethal EV-A71 challenge in both prophylactic and therapeutic treatment.In particular,E1 significantly reduces virus titers and muscle damage.E1 might represent a potential adjunct to EV-A71 treatment.