Innate and adaptive immune responses against picornaviruses and their counteractions: An overview

Picornaviruses, small positive-stranded RNA viruses, cause a wide range of diseases which is based on their differential tissue and cell type tropisms. This diversity is reflected by the immune responses, both innate and adaptive, induced after infection, and the subsequent interactions of the viruses with the immune system. The defense mechanisms of the host and the countermeasures of the virus significantly contribute to the pathogenesis of the infections. Important human pathogens are poliovirus, coxsackievirus, human rhinovirus and hepatitis A virus. These viruses are the beststudied members of the family, and in this review we want to present the major aspects of the reciprocal effects between the immune system and these viruses.

Adaptive immune response during hepatitis C virus infection

Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma.HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control.Liver damage and disease progression during HCV infection are driven by both viral and host factors.Specifically,adaptive immune response carries out an essential task in controllingnon-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery.HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion.To impair HCV-specific T cell reactivity,HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro-and antiapoptotic proteins.In this review,the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.

Effect of postoperative early enteral nutrition support on anti-tumor immune response and inflammatory response process in the elderly patients with esophageal cancer

Objective: To explore the effect of postoperative early enteral nutrition support on anti-tumor immune response and inflammatory response process in the elderly patients with esophageal cancer. Methods: A total of 110 cases of elderly patients with esophageal cancer who underwent radical operation in this hospital between January 2015 and December 2017 were divided into the parenteral nutrition group (n=57) who received parenteral nutrition support and the enteral nutrition group (n=53) who received enteral nutrition support according to the postoperative nutrition intervention methods. The differences in anti-tumor immune response and inflammatory response degree were compared between the two groups of patients immediately after the patients returned to the ward (T0), 48h after nutritional support (T1) and 72h after nutritional support (T2). Results: At T0, there was no statistically significant difference in the contents of Th1/Th2 immune response and Th17/Treg immune response indexes as well as inflammatory mediators in serum between the two groups of patients. At T1 and T2, serum Th1 cytokines IFN-γ and IL-12 contents of enteral nutrition group were higher than those of parenteral nutrition group whereas Th2 cytokines IL-4 and IL-13 contents were lower than those of parenteral nutrition group;serum contents of Th17 cytokines IL-6 and IL-17 as well as Treg cytokines TGF-β and IL-10 were lower than those of parenteral nutrition group;serum inflammatory mediators hs-CRP, PGE and HMGB1 contents were lower than those of parenteral nutrition group. Conclusion: Postoperative early enteral nutrition support can effectively regulate the Th1/Th2 and Th17/Treg immune response balance and inhibit the systemic inflammatory response in elderly patients with esophageal cancer.

Effects of different chemotherapy regimens before radical operation for lung cancer on cancer cell growth and anti-tumor immune response

Objective:To investigate the effects of different chemotherapy regimens before radical operation for lung cancer on cancer cell growth and antitumor immune response.Methods: A total of 180 patients with primary lung cancer who underwent surgery in this hospital between February 2013 and August 2017 were divided into the cisplatin group (n=93) who received cisplatin & paclitaxel chemotherapy and the lobaplatin group (n=87) who received lobaplatin & paclitaxel chemotherapy according to different preoperative neoadjuvant chemotherapy regimens. The differences among the expression of proliferation genes and apoptosis genes in tumor tissues as well as the contents of Th1/Th2 cytokines in serum were compared between the two groups.Results: Proliferation genes DDX17, GPx1, MACC1, RACK1 and SIRT1 mRNA expression levels in tumor tissue of lobaplatin group were lower than those of cisplatin group whereas LRRC3B mRNA expression level was higher than that of cisplatin group;apoptosis gene Fas, FasL and Caspase-3 mRNA expression levels were higher than those of cisplatin group whereas Survivin and Bcl-2 mRNA expression levels were lower than those of cisplatin group;serum Th1 cytokines IFN-γ and IL-12 contents were higher than those of cisplatin group whereas Th2 cytokines IL-5 and IL-10 contents were lower than those of cisplatin group.Conclusion: Lobaplatin chemotherapy before radical operation for lung cancer is more effective than cisplatin chemotherapy to inhibit the proliferation activity and enhance the apoptosis activity of lung cancer cells and optimize the anti-tumor immune response.

Effect of negative emotion on tumor load and anti-tumor immune response in bladder cancer infusion chemotherapyn

Objective: To study the effect of negative emotion on tumor load and anti-tumor immune response in bladder cancer infusion chemotherapy. Methods: Patients with advanced bladder cancer who received bladder infusion chemotherapy in the First People's Hospital of Ziyang between May 2014 and December 2016 were selected and divided into the control group without negative emotions, the anxiety group with anxiety, the depression group with depression and the anxiety depression group with both anxiety and depression according to the assessment results of HAMA scale and HAMD scale. The contents of tumor markers in serum, the contents of immune cells in peripheral blood and the expression of apoptosis genes in urine were detected during chemotherapy. Results: DKK-1, DKK-3, OPN and CYFRA21-1 contents in serum as well as PD-1+CD4+T cell, PD-1+CD8+T cell and B7-H1+CD11c+DC cell contents in peripheral blood of anxiety group, depression group and anxiety depression group were significantly higher than those of control group while DAP2IP, Fas, FasL, Caspase-8 and PTEN protein expression in urine were significantly lower than those of control group, and DKK-1, DKK-3, OPN and CYFRA21-1 contents in serum as well as PD-1+CD4+T cell, PD-1+CD8+T cell and B7-H1+CD11c+DC cell contents in peripheral blood of anxiety depression group were significantly higher than those of anxiety group and depression group while DAP2IP, Fas, FasL, Caspase-8 and PTEN protein expression in urine were significantly lower than those of anxiety group and depression group. Conclusion: The anxiety and depression in bladder cancer infusion chemotherapy can suppress the expression of apoptosis genes and the anti-tumor immune response to lead to more vigorous proliferation of cancer cells.

Modulation of immune response in experimental Chagas disease

Trypanosoma cruzi(T. cruzi), the etiological agent of Chagas disease, affects nearly 18 million people in Latin America and 90 million are at risk of infection. The parasite presents two stages of medical importance in the host, the amastigote, intracellular replicating form, and the extracellular trypomastigote, the infective form. Thus infection by T. cruzi induces a complex immune response that involves effectors and regulatory mechanisms. That is why control of the infection requires a strong humoral and cellular immune response; hence, the outcome of host-parasite interaction in the early stages of infection is extremely important. A critical event during this period of the infection is innate immune response, in which the macrophage's role is vital. Thus, after being phagocytized, the parasite is able to develop intracellularly; however, during later periods, these cells induce its elimination by means of toxic metabolites. In turn, as the infection progresses, adaptive immune response mechanisms are triggered through the TH1 and TH2 responses. Finally, T. cruzi, like other protozoa such as Leishmania and Toxoplasma, have numerous evasive mechanisms to the immune response that make it possible to spread around the host. In our Laboratory we have developed a vaccination model in mice with Trypanosoma rangeli, nonpathogenic to humans, which modulates the immune response to infection by T. cruzi, thus protecting them. Vaccinated animals showed an important innate response(modulation of NO and other metabolites, cytokines, activation of macrophages), a strong adaptive cellular response and significant increase in specific antibodies. The modulation caused early elimination of the parasites, low parasitaemia, the absence of histological lesions and high survival rates. Even though progress has been made in the knowledge of some of these mechanisms, new studies must be conducted which could target further prophylactic and therapeutic trials against T. cruzi infection.

Anti-tumor response induced by immunologically modified carbon nanotubes and laser irradiation using rat mammary tumor model

The ideal treatment modality for metastatic cancer would be a local treatment that can destroy primary tumors while inducing an effective systemic anti-tumor response.To this end,we de-veloped laser immunotherapy,combining photothermal laser application with an immunoadju-vant for the treatment of metastatic cancer.Additionally,to enhance the selective photothermal effect,we integrated light-absorbing nanomaterials into this innovative treatment.Specifically,we developed an immunologically modified carbon nanotube combining single-walled carbon nanotubes(SWNTs)with the immunoadjuvant glycated chitosan(GC).To determine the ef-fectiveness of laser iradiation,a series of experiments were performed using two different irra-diation durations-5 and 10 min.Rats were inoculated with DMBA-4 cancer cells,a metastatic cancer cell line.The treatment group of rats receiving laser irradiation for 10 min had a 50%long-term survival rate without residual primary or metastatic tumnors.The treatment group of rats receiving laser irradiation for 5 min had no long-term survivors;all rats died with multiple metastases at several distant sites.Therefore,Laser+SWNT-GC treatment with 10 min of laser irradiation proved to be efective at reducing tumor size and inducing long-term anti-tumor immunity.

Contribution of Toll-like receptors to the control of hepatitis B virus infection by initiating antiviral innate responses and promoting specific adaptive immune responses

It is well accepted that adaptive immunity plays a key role in the control of hepatitis B virus （HBV） infection. In contrast, the contribution of innate immunity has only received attention in recent years. Toll-like receptors （TLRs） sense pathogen-associated molecule patterns and activate antiviral mechanisms, including intracellular antiviral pathways and the production of antiviral effector interferons （IFNs） and pro-inflammatory cytokines. Experimental results from in vitroand in vivo models have demonstrated that TLRs mediate the activation of cellular signaling pathways and the production of antiviral cytokines, resulting in a suppression of HBV replication. However, HBV infection is associated with downregulation of TLR expression on host cells and blockade of the activation of downstream signaling pathways. In primary HBV infection, TLRs may slow down HBV infection, but contribute only indirectly to viral clearance. Importantly, TLRs may modulate HBV-specific T- and B-cell responses in vivo, which are essential for the termination of HBV infection. Thus, TLR agonists are promising candidates to act as immunomodulators for the treatment of chronic HBV infection. Antiviral treatment may recover TLR expression and function in chronic HBV infection and may increase the efficacy of therapeutic approaches based on TLR activation. A combined therapeutic strategy with antiviral treatment and TLR activation could facilitate the restoration of HBV-specific immune responses and thereby, achieve viral clearance in chronically infected HBV patients.

Hydroxyapatite nanoparticles drive the potency of Toll-like receptor 9 agonist for amplified innate and adaptive immune response

The potency of Toll-like receptor 9(TLR9)agonist to drive innate immune response was limited due to immune suppression or tolerance during TLR9 signaling activation in immune cells.Herein we addressed this problem by introducing hydroxyapatite nanoparticles(HANPs)to CpG ODN(CpG),a TLR9 agonist.The study revealed that HANPs concentration and durationdependently reprogramed the immune response by enhancing the secretion of immunostimulatory cytokines(tumor necrosis factorα(TNFα)or IL-6)while reducing the production of immunosuppressive cytokine(IL-10)in macrophages in response to CpG.Next,the enhanced immune response benefited from increased intracellular Ca2+in macrophage by the addition of HANPs.Further,we found exposure to HANPs impacted the mitochondrial function of macrophages in support of the synthesis of adenosine triphosphate(ATP),the production of nicotinamide adenine dinucleotide(NAD),and reactive oxygen species(ROS)in the presence or absence of CpG.In vaccinated mice model,only one vaccination with a mixture of CpG,HANPs,and OVA,a model antigen,allowed the development of a long-lasting balanced humoral immunity in mice without any histopathological change in the local injection site.Therefore,this study revealed that HANPs could modulate the intracellular calcium level,mitochondrial function,and immune response in immune cells,and suggested a potential combination adjuvant of HANPs and TLR9 agonist for vaccine development.

Impact of adaptive immune response and cellular infection on delayed virus dynamics with multi-stages of infected cells

In this investigation,we propose and analyze a virus dynamics model with multi-stages of infected cells.The model incorporates the effect of both humoral and cell-mediated immune responses.We consider two modes of transmissions,virus-to-cell and cell-to-cell.Multiple intracellular discrete-time delays have been integrated into the model.The incidence rate of infection as well as the generation and removal rates of all compartments are described by general nonlinear functions.Wc derive five threshold parameters which determine the existence of the equilibria of the model under consideration.A set of conditions on the general functions has been established which is sufficient to investigate the global stability of the five equilibria of the model.The global asymptotic stability of all equilibria is proven by utilizing Lyapunov function and LaSalle’s invariance principle.The theoretical results are illustrated by numerical simulations of the model with specific forms of the general functions.

Low Dose of IL-12 Stimulates T Cell Response in Cultures of PBMCs Derived from Non Small Cell Lung Cancer Patients

Cancer induces tolerance by suppressing immune function, modulating the T helper activity and causing an imbalance of cytokines produced by T cells. IL-12 is an immune regulatory cytokine with potent anti-tumor activity and its signalling network leads to polarization of na?ve CD4+ T cells into Th1. In pre-clinical studies, administration of recombinant IL-12 by intravenous injection or IL-12 plasmid DNA by intra-tumoral injection showed some anti-tumor effects, measurable immunological responses, but also important dose-dependent side effects. We investigated the ability of low doses of IL-12 to modulate the T cell subpopulations in cultures of PBMCs derived from Non Small Lung Cancer (NSCLC) patients and to induce lysis of lung adenocarcinoma cells by T cells. PBMCs were stimulated with different doses of IL-12 and T cell phenotype was evaluated. IL-12 at 0.01 pg/ml significantly increased the number of CD4 and CD8 T cells, in particular of CD4/IFNγ producing cells. IL-12 did not stimulate T regulatory, but it increased the lysis of lung adenocarcinoma cells induced by T cells. Our results showed that low doses of IL-12 modulates T cell sub-populations in vitro and it increased their lytic activity on adenocarcinoma cells, thus we hypothesize the use of low dose of IL-12 as a therapeutic tool against pathologies characterized by a T cell imbalance, in order to promote an immuno-modulation.

Effect of nutritional support + intravenous chemotherapy on anti-tumor immunity and cancer cell proliferation in patients with colon cancer complicated by incomplete intestinal obstruction

Objective:To study the effect of nutritional support + intravenous chemotherapy on anti-tumor immunity and cancer cell proliferation in patients with colon cancer complicated by incomplete intestinal obstruction.Methods: Patients with colon cancer complicated by incomplete intestinal obstruction who were treated in Midi Branch, Pangang Group General Hospital between March 2015 and October 2017 were selected and randomly divided into the nutrition group who accepted nutritional support + FOLFOX4 intravenous chemotherapy and the control group who accepted FOLFOX4 intravenous chemotherapy alone, and they underwent surgery after two cycles of chemotherapy. The contents of immune cells in peripheral blood and the contents of immune cytokines in serum were determined before chemotherapy and two cycles after chemotherapy;the expression levels of proliferation genes in colon cancer lesions were determined after surgical resection.Results:Compared with those of same group before chemotherapy, peripheral blood Treg, Th9, Th17 and Th22 contents as well as serum IL-4, IL-9, IL-10, TGF-β1, IL-17 and IL-22 contents of nutrition group were decreased significantly after chemotherapywhereas peripheral blood Treg, Th9, Th17 and Th22 contents as well as serum IL-4, IL-9, IL-10, TGF-β1, IL-17 and IL-22 contents of control group did not change significantly after chemotherapy, and compared with those after chemotherapy between groups, peripheral blood Treg, Th9, Th17 and Th22 contents as well as serum IL-4, IL-9, IL-10, TGF-β1, IL-17 and IL-22 contents of nutrition group were significantly lower than those of control group, and CyclinD1, Bcl-2, USP22, VEGF and N-cadherin mRNA expression were not different from those of control group.Conclusion:Nutritional support + intravenous chemotherapy can improve the anti-tumor immune response without affecting the proliferation of cancer cells in the lesion of patients with colon cancer complicated by incomplete intestinal obstruction.

Dynamic analysis of a latent HIV infection model with CTL immune and antibody responses

This paper develops a mathematical model to investigate the Human Immunodeficiency Virus(HIV)infection dynamics.The model includes two transmission modes(cell-to-cell and cell-free),two adaptive immune responses(cytotoxic T-lymphocyte(CTL)and antibody),a saturated CTL immune response,and latent HIV infection.The existence and local stability of equilibria are fully characterized by four reproduction numbers.Through sensitivity analyses,we assess the partial rank correlation coefficients of these reproduction numbers and identify that the infection rate via cell-to-cell transmission,the number of new viruses produced by each infected cell during its life cycle,the clearance rate of free virions,and immune parameters have the greatest impact on the reproduction numbers.Additionally,we compare the effects of immune stimulation and cell-to-cell spread on the model's dynamics.The findings highlight the significance of adaptive immune responses in increasing the population of uninfected cells and reducing the numbers of latent cells,infected cells,and viruses.Furthermore,cell-to-cell transmission is identified as a facilitator of HIV transmission.The analytical and numerical results presented in this study contribute to a better understanding of HIV dynamics and can potentially aid in improving HIV management strategies.

Harnessing immunity:Immunomodulatory therapies in COVID-19

An overly exuberant immune response,characterized by a cytokine storm and uncontrolled inflammation,has been identified as a significant driver of severe coronavirus disease 2019(COVID-19)cases.Consequently,deciphering the intricacies of immune dysregulation in COVID-19 is imperative to identify specific targets for intervention and modulation.With these delicate dynamics in mind,immunomodulatory therapies have emerged as a promising avenue for miti-gating the challenges posed by COVID-19.Precision in manipulating immune pathways presents an opportunity to alter the host response,optimizing antiviral defenses while curbing deleterious inflammation.This review article compre-hensively analyzes immunomodulatory interventions in managing COVID-19.We explore diverse approaches to mitigating the hyperactive immune response and its impact,from corticosteroids and non-steroidal drugs to targeted biologics,including anti-viral drugs,cytokine inhibitors,JAK inhibitors,convalescent plasma,monoclonal antibodies(mAbs)to severe acute respiratory syndrome coronavirus 2,cell-based therapies(i.e.,CAR T,etc.).By summarizing the current evidence,we aim to provide a clear roadmap for clinicians and researchers navigating the complex landscape of immunomodulation in COVID-19 treatment.CS Glucocorticoids are among the most widely prescribed drugs with their immune-suppressive and anti-inflammatory effect[84].The current guidelines for the treatment of COVID-19 recommend against the use of dexamethasone or other systemic CS in non-hospitalized patients in the absence of another indication[70].The RECOVERY trial demonstrates the reduced 28-d mortality among hospitalized patients with COVID-19 using dexamethasone compared to the usual standard of care,along with other investigators,such as Ahmed and Hassan[85].The benefit of dexamethasone was seen only among participants receiving either oxygen alone or invasive mechanical ventilation at randomization but not among those receiving no respiratory support at enrollment[85].In a systematic review and meta-analysis,Albuquerque et al[86]showed that in comparison to tocilizumab,baricitinib,and sarilumab are associated with high probabilities of similar mortality reductions among hospitalized COVID-19 concurrently treated with CS.As a result of the absence of SARS-CoV-2-specific antiviral medications,the effectiveness of COVID-19 treatments is reduced.Several COVID-19 therapies are now under investigation.However,the majority of them lack specificity,efficacy,and safety[87].Immunotherapy is a ground-breaking medical treatment that manipulates the immune system to fight diseases.Translational research is rapidly progressing,recognized as a significant breakthrough in 2013[88].Among the immunotherapeutic options for treating COVID-19 are Immunoglobulin,CP,antibodies,mAbs(mAbs),NK cells,T cells,TLR,cytokine therapies and immune modulators.

MAP Kinases in Immune Responses

MAP kinases are evolutionarily conserved signaling regulators from budding yeast to mammals and play essential roles in both innate and adaptive immune responses.There are three main families of MAPKs in mammals.Each of them has its own activators,inactivators,substrates and scaffolds,which altogether form a fine signaling network in response to different extracellular or intracellular stimulation.In this review,we summarize recent advances in understanding of the regulation of MAP kinases and the roles of MAP kinases in innate and adaptive immune responses.Cellular & Molecular Immunology.2005;2(1):20-27.

Thermal ablation and immunotherapy for hepatocellular carcinoma:Recent advances and future directions

Hepatocellular carcinoma(HCC)is one of most common cancers that cause death in the world.Thermal ablation(TA)is an important alternative treatment method for HCC patients who are not appropriate for surgery or liver transplantation.Particularly for small and early HCCs,TA can be considered as the first-line curative treatment.However,local and distant recurrence rates are still high even though the TA equipment and technology develop rapidly.Immunotherapy is a novel systemic treatment method to enhance the anti-tumor immune response of HCC patients,which has the potential to reduce the tumor recurrence and metastasis.The combination of local TA and systemic immunotherapy for HCCs may be an ideal treatment for enhancing the efficacy of TA and controlling the recurrence.Herein we summarize the latest progress in TA,immunotherapy,and their combination for the treatment of patients with HCC and discuss the limitations and future research directions of the combined therapy.

COVID-19 and gut immunomodulation

The disease coronavirus disease 2019(COVID-19)is a severe respiratory illness that has emerged as a devastating health problem worldwide.The disease outcome is heterogeneous,and severity is likely dependent on the immunity of infected individuals and comorbidities.Although symptoms of the disease are primarily associated with respiratory problems,additional infection or failure of other vital organs are being reported.Emerging reports suggest a quite common co-existence of gastrointestinal(GI)tract symptoms in addition to respiratory symptoms in many COVID-19 patients,and some patients show just the GI symptoms.The possible cause of the GI symptoms could be due to direct infection of the epithelial cells of the gut,which is supported by the fact that(1)The intestinal epithelium expresses a high level of angiotensin-converting enzyme-2 and transmembrane protease serine 2 protein that are required for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)entry into the cells;(2)About half of the severe COVID-19 patients show viral RNA in their feces and various parts of the GI tract;and(3)SARS-CoV-2 can directly infect gut epithelial cells in vitro(gut epithelial cells and organoids)and in vivo(rhesus monkey).The GI tract seems to be a site of active innate and adaptive immune responses to SARS-CoV-2 as clinically,stool samples of COVID-19 patients possess proinflammatory cytokines(interleukin 8),calprotectin(neutrophils activity),and immunoglobulin A antibodies.In addition to direct immune activation by the virus,impairment of GI epithelium integrity can evoke immune response under the influence of systemic cytokines,hypoxia,and changes in gut microbiota(dysbiosis)due to infection of the respiratory system,which is confirmed by the observation that not all of the GI symptomatic patients are viral RNA positive.This review comprehensively summarizes the possible GI immunomodulation by SARS-CoV-2 that could lead to GI symptoms,their association with disease severity,and potential therapeutic interventions.

Enhanced host immune responses in presence of HCV facilitate HBV clearance in coinfection

Hepatitis B virus(HBV)/Hepatitis C virus(HCV)coinfection is frequently observed because of the common infection routine.Despite the reciprocal inhibition exerted by HBV and HCV genomes,the coinfection of HBV and HCV is associated with more severe forms of liver diseases.However,the complexity of viral interference and underlying pathological mechanism is still unclarified.With the demonstration of absence of direct viral interplay,some in vitro studies suggest the indirect effects of viral-host interaction on viral dominance outcome.Here,we comprehensively investigated the viral replication and host immune responses which might mediate the interference between viruses in HBV/HCV coinfected Huh7-NTCP cells and immunocompetent HCV human receptors transgenic ICR mice.We found that presence of HCV significantly inhibited HBV replication in vitro and in vivo irrespective of the coinfection order,while HBV did not affect HCV replication.Pathological alteration was coincidently reproduced in coinfected mice.In addition to the participation of innate immune response,an involvement of HCV in up-regulating HBV-specific immune responses was described to facilitate HBV clearance.Our systems partially recapitulate HBV/HCV coinfection and unveil the uncharacterized adaptive anti-viral immune responses during coinfection,which renews the knowledge on the nature of indirect viral interaction during HBV/HCV coinfection.

流感病毒感染人扁桃体类器官的免疫效应

目的 建立人扁桃体免疫类器官模型并探讨流感病毒感染后产生的免疫学效应。方法 经扁桃体腺样体肥大手术摘除后的人扁桃体组织在经过单个核细胞梯度离心后,利用2.5D-Transwell进行体外培养并添加IL-2及Baff等成细胞因子促扁桃体类器官(tonsil organoids, TO)的形成。通过单细胞转录组测序(single cell RNA sequencing, scRNA-seq)技术,分析流感病毒细胞受体在类器官各细胞亚群的分布;体外感染流感病毒,使用免疫荧光法(IF)和流式细胞术(FCM)检测扁桃体类器官感染病毒后的免疫学效应。结果 于体外成功诱导扁桃体类器官;scRNA-seq分析结果显示流感病毒细胞受体广泛表达于所有的细胞类型中。流感病毒感染48 h后,刺激扁桃体类器官产生大量可分泌特异性IgG抗体的浆细胞和记忆性B细胞。病毒直接感染还促进CD8^(+)T细胞分泌细胞因子TNF-α与IL-2及CD4^(+)T细胞分泌细胞因子TNF-α、IFN-γ和IL-2。结论 人扁桃体类器官在体外可以被成功诱导且在培养第6天左右达到成熟;流感病毒受体广泛分布于人扁桃体类器官的各细胞亚型;流感病毒可通过受体直接感染T细胞,刺激T细胞活化并分泌细胞因子;同时流感病毒直接感染也可促B细胞分化为浆细胞分泌IgG抗体,并在后期诱导记忆性B细胞的形成。

具有两种传播方式和适应性免疫时滞的HBV感染模型研究

提出了一类具有饱和发生率和适应性免疫反应时滞的HBV感染模型,同时考虑两种感染途径.该模型包括未感染肝细胞、感染肝细胞、游离HBV病毒、CTL免疫反应和抗体响应5个仓室.定义5个阈值:感染基本再生数R_(0),抗体免疫再生数R_(1),CTL免疫再生数R_(2),CTL免疫竞争再生数R_(3)和抗体免疫竞争再生数R_4.得到了模型平衡点的存在唯一性.通过分析特征方程、构造Lyapunov泛函和Lasalle不变原理,建立了各类平衡点局部以及全局渐近稳定性的判定准则.