CRISPR-Edited Stem Cells in a Patient with HIV and Acute Lymphocytic Leukemia.

The safety of CRISPR (clustered regularly interspaced short palindromic repeats)-based genome editing in the context of human gene therapy is largely unknown. CCR5 is a reasonable but not absolutely protective target for a cure of human immunodeficiency virus type 1 (HIV-1) infection, because CCR5-null blood cells are largely resistant to HIV-1 entry. We transplanted CRISPR-edited CCR5-ablated hematopoietic stem and progenitor cells (HSPCs) into a patient with HIV-1 infection and acute lymphoblastic leukemia. The acute lymphoblastic leukemia was in complete remission with full donor chimerism, and donor cells carrying the ablated CCR5 persisted for more than 19 months without gene editing-related adverse events. The percentage of CD4+ cells with CCR5 ablation increased by a small degree during a period of antiretroviral-therapy interruption. Although we achieved successful transplantation and long-term engraftment of CRISPR-edited HSPCs, the percentage of CCR5 disruption in lymphocytes was only approximately 5%, which indicates the need for further research into this approach. (Funded by the Beijing Municipal Science and Technology Commission and others; ClinicalTrials.gov number, NCT03164135.).

Duration of SARS-CoV-2 RNA shedding and factors associated with prolonged viral shedding in patients with COVID-19.

To investigate the factors associated with the duration of severe acute respiratory syndrome coronavirus 2 RNA shedding in patients with coronavirus disease 2019 (COVID-19). A retrospective cohort of COVID-19 patients admitted to a designated hospital in Beijing was analyzed to study the factors affecting the duration of viral shedding. The median duration of viral shedding was 11 days (IQR, 8-14.3 days) as measured from illness onset. Univariate regression analysis showed that disease severity, corticosteroid therapy, fever (temperature>38.5°C), and time from onset to hospitalization were associated with prolonged duration of viral shedding (P < .05). Multivariate regression analysis showed that fever (temperature>38.5°C) (OR, 5.1, 95%CI: 1.5-18.1), corticosteroid therapy (OR, 6.3, 95%CI: 1.5-27.8), and time from onset to hospitalization (OR, 1.8, 95%CI: 1.19-2.7) were associated with increased odds of prolonged duration of viral shedding. Corticosteroid treatment, fever (temperature>38.5°C), and longer time from onset to hospitalization were associated with prolonged viral shedding in COVID-19 patients.

Integrated analysis reveals important differences in the gut and oropharyngeal microbiota between children with mild and severe hand, foot, and mouth disease.

Little is known about alternation and difference in gut microbiota between patients with mild and severe hand, foot, and mouth disease (HFMD). We investigated the differences in gut and oropharynx microbiota between mild and severe HFMD in young children and changes in bacterial profiles as the disease progresses from acute to convalescent phase. Forty-two patients with confirmed HFMD were studied, among which 32 had severe HFMD and 10 had mild HFMD. First rectal swabs were collected from all patients at an average of 2 days (acute phase) after the onset of symptoms, and second rectal swabs were collected from 8 severe patients at day 9 (convalescent phase) after the onset. Oropharyngeal swabs were obtained from 10 patients in the acute phase and 6 in the convalescent phase. 16S rRNA sequencing was performed for all 70 samples. Compared with mild HFMD, severe HFMD exhibited significantly decreased diversity and richness of gut microbiota. Gut microbiota bacterial profiles observed in the acute and convalescent phases resembled each other but differed from those in mild cases. Additionally, 50% of patients with severe HFMD in the acute phase harboured a dominant pathobiontic bacterial genus. However, none of the patients with mild HFMD had such bacteria. Similar bacterial compositions in oropharynx microbiota were detected between mild and severe cases. Our findings indicate that severe HFMD exhibits significantly impaired diversity of gut microbiota and frequent gut and oropharyngeal inflammation-inducing bacteria. However, the results should be interpreted with caution as the number of subjects was limited.

Profile of specific antibodies to the SARS-CoV-2.

In this work, we studied the profile of IgM and IgG antibody responses to SARS-CoV-2 in 32 patients with COVID-19 from day 1 to day 24. IgM remained measurable for a much shorter period than IgG, suggesting that IgG antibody may represent the primary immune response.

Telomerase activity of HIV-1-specific CD8+ T cells: constitutive up-regulation in controllers and selective increase by blockade of PD ligand 1 in progressors.

Exhaustion of virus-specific T cells may play an important role in the pathophysiology of chronic viral infections. Here, we analyzed telomere length and telomerase activity in HIV-1-specific CD8+ T cells from progressors or controllers to determine underlying molecular pathways of T-cell exhaustion and senescence. Telomere lengths of HIV-1-specific CD8+ T cells from progressors were significantly shorter compared with autologous cytomegalovirus (CMV)/Epstein-Barr virus (EBV)-specific CD8+ T cells or bulk CD8+ T cells, while telomere lengths from controllers significantly exceeded those of autologous bulk CD8+ T cells and reached a similar level as HIV-1-specific CD8+ T cells collected during primary HIV-1 infection. Telomere length stabilization in controllers corresponded to high levels of constitutive telomerase activity, which was associated with preservation of cytotoxic and proliferative properties. Conversely, limited constitutive telomerase activity was observed in HIV-1-specific CD8+ T cells from progressors, although an increase in both telomere length and telomerase activity was achieved in antigenic-peptide-stimulated cells from progressors after blocking the PD-1/PD ligand 1 (PD-L1) pathway. Collectively, these data suggest a causal role of telomere shortening for the functional deficiencies of HIV-1-specific CD8+ T cells in chronic progressive infection, while high constitutive telomerase activities appears to contribute to maintenance of polyfunctional HIV-1-specific CD8+ T cells from HIV-1 controllers.

Pathological features of COVID-19-associated lung injury: a preliminary proteomics report based on clinical samples.

The COVID-19 pandemic has emerged as a global health emergency due to its association with severe pneumonia and relative high mortality. However, the molecular characteristics and pathological features underlying COVID-19 pneumonia remain largely unknown. To characterize molecular mechanisms underlying COVID-19 pathogenesis in the lung tissue using a proteomic approach, fresh lung tissues were obtained from newly deceased patients with COVID-19 pneumonia. After virus inactivation, a quantitative proteomic approach combined with bioinformatics analysis was used to detect proteomic changes in the SARS-CoV-2-infected lung tissues. We identified significant differentially expressed proteins involved in a variety of fundamental biological processes including cellular metabolism, blood coagulation, immune response, angiogenesis, and cell microenvironment regulation. Several inflammatory factors were upregulated, which was possibly caused by the activation of NF-κB signaling. Extensive dysregulation of the lung proteome in response to SARS-CoV-2 infection was discovered. Our results systematically outlined the molecular pathological features in terms of the lung response to SARS-CoV-2 infection, and provided the scientific basis for the therapeutic target that is urgently needed to control the COVID-19 pandemic.

Pathological Findings in Myasthenia Gravis Patients with Thymic Hyperplasia and Thymoma.

Thymectomy is routinely carried out in patients with myasthenia gravis (MG) and thymomas. However, there is still a dispute as to whether MG patients with thymic hyperplasia should undergo thymectomy. We aimed to investigate the pathological findings in the thymus in patients with co-existing MG and thymic hyperplasia or thymomas treated with thymectomy, as well as effects of immunosuppression. Thirty-three patients with MG were selected and grouped accordingly: patients with no thymic abnormalities, patients with thymic hyperplasia, and patients with thymomas. All patients were treated with methylprednisolone alongside immunosuppression. A separate cohort of 24 MG patients with thymic hyperplasia or thymomas and treated with thymectomy were selected. As controls, 5 patients with thymomas or thymic carcinoma without MG were selected. Expression of CD5, extracellular regulated protein kinases1/2 mitogen activated protein kinase (ERK1/2MAPKs) and CD95 ligand (FasL) in the thymus was examined. Methylprednisolone and immunosuppressive therapy are highly effective in MG patients with normal thymus tissue and MG patients with thymic hyperplasia compared to MG patients with thymomas alone. CD5 expression was highest in MG patients with thymic hyperplasia, correlating with expression of ERK1/2MAPKs. FasL expression was similar across all groups. Thymomas may be distinguished from thymic hyperplasia by expression of CD5 and ERK1/2MAPKs. Thymectomy is the preferred treatment for MG patients with thymomas but may not be necessary in MG patients with thymic hyperplasia who are treated with immunosuppressive therapy.

Syphilis Infection Differentially Regulates the Phenotype and Function of γδ T Cells in HIV-1-Infected Patients Depends on the HIV-1 Disease Stage.

A rapidly escalating outbreak of syphilis infection has been affected men who have sex with men, particularly those with HIV-1 infection. γδ T cells are unconventional immune cells with two main subsets, Vδ1 T cells and Vδ2 T cells, which possess a combination of innate and adaptive immune features allowing them against HIV-1. However, whether syphilis infection affects the phenotype and function of γδ T cells in HIV-1-infected patients remains unclear, especially in acute HIV-1 infection (AHI). In this study, we enrolled 57 HIV-1-infected patients (24 with HIV-1 infection only and 33 coinfected with syphilis) from an acute HIV-1-infected cohort in Beijing (PRIMO). A comprehensive analysis of γδ T-cell phenotype and function was performed by flow cytometry. We found syphilis coinfection could reverse the imbalance of Vδ1/Vδ2 ratio in AHI. Syphilis infection results in decreased γδ T-cell activation in AHI, but increased γδ T-cell activation in chronic HIV-1 infection (CHI). Moreover, patients with CHI had larger numbers of IL-17-producing γδ T cells than those with AHI, regardless of syphilis status. Thus, syphilis affected the γδ T-cell immune response differently in patients depending on the stages of HIV-1 disease. In addition, the percentage of IL-17-producing γδ T cells was positively correlated with the percentage of neutrophils. These results suggest that the γδ T-cell/IL-17/neutrophil axis is involved in HIV-1 pathogenesis and disease progression. Taken together, our observations provide new insight into the roles of γδ T cells in immunopathogenesis of syphilis and HIV-1 coinfection, particularly during AHI, and our findings may be helpful for the prevention of syphilis and other sexually transmitted infections and highlight the great significance on the remedy of patients coinfected with HIV-1.

In vitro inhibition of HIV-1 replication in autologous CD4+ T cells indicates viral containment by multifactorial mechanisms.

HIV-1-specific cytotoxic T lymphocytes (CTLs) and neutralizing antibodies (NAbs) are present during chronic infection, but the relative contributions of these effector mechanisms to viral containment remain unclear. Here, using an in vitro model involving autologous CD4+ T cells, primary HIV-1 isolates, HIV-1-specific CTLs, and neutralizing monoclonal antibodies, we show that b12, a potent and broadly neutralizing monoclonal antibody to HIV-1, was able to block viral infection when preincubated with virus prior to infection, but was much less effective than CTLs at limiting virus replication when added to infected cell cultures. However, the same neutralizing antibody was able to contain viruses by antibody-dependent cell-mediated virus inhibition in vitro, which was mediated by natural killer cells (NKs) and dependent on an Fc-Fc receptor interaction. Meanwhile, bulk CTLs from HIV-1 controllers were more effective in suppression of virus replication than those from progressors. These findings indicate that control of HIV-1 replication in activated CD4+ T cells is ineffectively mediated by neutralizing antibodies alone, but that both CTLs and antibody-dependent NK-mediated immune mechanisms contribute to viral containment. Our study systemically compared three major players in controlling HIV-1 infection, CTLs, NAbs, and NKs, in an autologous system and highlighted the multifactorial mechanisms for viral containment and vaccine success.

Expression of dendritic cell-specific intercellular adhesion molecule 3 grabbing nonintegrin on dendritic cells generated from human peripheral blood monocytes.

AIM: To generate dendritic cells (DCs) from human peripheral blood and to detect the expression of dendritic cell-specific intercellular adhesion molecule 3 grabbing nonintegrin (DC-SIGN; CD209) for the further study of DC-SIGN in hepatitis C virus (HCV) transmission. METHODS: Peripheral blood monocytes were isolated from blood of healthy individuals by Ficoll-Hypaque sedimentation and cultured in complete medium containing rhGM-CSF and rhIL-4. Cells were cultured for seven days, with cytokine addition every two days to obtain immature DCs. Characteristics of the cultured cells were observed under light and scanning microscope, and the expression of DC-SIGN was detected by immunofluorescence staining. RESULTS: After seven-day culture, a large number of cells with typical characteristics of DCs appeared. Their characteristics were observed under light and scanning electron microscope. These cells had a variety of cell shapes such as those of bipolar elongate cells, elaborate stellate cells and DCs. DC-SIGN was detected by immunofluorescence staining and its expression level on cultivated dendritic cells was high. CONCLUSION: DCs with a high expression of DC-SIGN can be generated from human peripheral blood monocytes in complete medium containing rhGM-CSF and rhIL-4.

[Immune Effects and Mechanisms of HIV-specific Antibodies Against Viral Infection].

Broadly neutralizing antibodies (bNAbs) have demonstrated a protective role from experimental challenge in non-human primates and humanized mouse models. Recently, bNAbs 3BNC117 and VRC01were assessed in a phase-I clinical trial, and were shown to lower plasma viremia in human immunodeficiency virus(HIV)-1-infected individuals not receiving antiretroviral therapy. However, induction of these types of antibodies by vaccination iS extremely difficult. Moreover, the 31% protection observed in the RV144 vaccine trial in the absence of detectable bNAbs in blood samples suggested the important role of additional inhibitory functions of the antibodies that control infection and replication of HIV. Increasing evidence suggests that immunoglobulin-G Fcγ receptor-mediated inhibition of antibodies present at the mucosal site may have a protective role against mucosal transmission of HIV. Dendritic cells and macrophages express such Fc receptors on their surface, and may have a decisive role in early mucosal transmission because they have been proposed to be the first HIV target at the mucosal site. Therefore, new vaccination strategies involving induction of such non-neutralizing inhibitory antibodies and other antiviral functions, in addition to bNAbs, should be developed.

[Functional Analyses of HIV-1 Specific Cytotoxic T Lymphocyte Clones].

Human immunodeficiency virus type 1(HIV-1)-specific CD8 cytotoxic T-lymphocytes(CTL)are essential components of the protective immunity against HIV-1infection.However,due to heterogeneous responses of CTL to HIV-1,our general understanding of CTL efficacy in the context of HIV-1infection remains limited. To better understand the factors that determine the potency of HIV-1specific CTL responses, this study directly investigated the relationship between different functional attributes associated with CTL response at the single cell level by using HIV-1specific CTL clones isolated in vitro. Twelve selected HIV-1CTL clones with various HLA restriction and specific antigen epitopes were comprehensively evaluated by several functional assays(e.g., killing capacity, degranulation, production of multiple cytokines and polyfunctionality, as well as the expression of lytic granule components and exhaustion molecules).Our principal findings were that the killing capacity of the CTL response was most closely associated with their degranulation capacity. Additionally, the killing and the degranulation capacity of CTL was associated with the levels and polyfunctionality of the cytokines secreted later. These findings implicate that multiple functional CTL responses are coordinately regulated and determined.

[Exosome: Trojan horse in immunotherapy].

Exosomes are small membrane-bound vesicles that are secreted by a multitude of eukaryocytes as a consequence of fusion of multivesicular bodies with the plasma membrane. Exosomes can play critical roles in different physiological processes depending on their origins. Exosomes secreted from professional antigen-presenting cells are enriched in MHC class I and II complexes, costimulatory molecules, hsp 70 and hsp 90 chaperones, therefore exosomes, like Trojan horse, are of importance of immunoregulation in vivo and in vitro. The review will present current trends of research on the fundamental properties, production and purification of exosomes, and will focus on their implementation in cancer and virus immunotherapy as a novel cell-free peptide-based vaccine.

Development of an In-House Multiplex Nested RT-PCR Method for Detecting Acute HIV-1 Infection in High Risk Populations.

BACKGROUND: The detection of acute HIV infection (AHI) among high risk populations can help reduce secondary transmission of HIV. The nucleic acid testing (NAT) can shorten the test window period by up to 7-12 days. In this study, we describe an in-house NAT based on the multiplex nested RT-PCR method to detect the HIV RNA. We also evaluated it in a high risk cohort in Beijing. METHODS: Four primer pairs were designed and evaluated for the detection of different HIV-1 subtypes in group M. Multiplex RT-PCR and nested PCR were performed. The sensitivity, specialty, primers compatibility among HIV subtypes were evaluated simultaneously. In an MSM cohort in Beijing during a 3-year period, a total of 11,808 blood samples that were negative by ELISA or indeterminate by Western blot were analyzed by this multiplex nested RT-PCR with pooling strategy. RESULTS: The multiplex nested RT-PCR was successfully applied for the detection of at least six HIV-1 subtypes. The sensitivity was 40 copies/ml and the specificity was 100%. A total of 29 people were tested HIV-1 positive with acute infection in a MSM cohort of Beijing during a 3 years period. CONCLUSION: This multiplex nested RT-PCR provides a useful tool for the rapid detection of acute HIV-1 infection. When used in combination with the 3(rd) generation ELISA, it can improve the detection rate of HIV infection, especially in the source limited regions.

HIV burden in men who have sex with men: a prospective cohort study 2007-2012.

We conducted a prospective cohort study among HIV-negative MSM aged 18 years or older between 2007 and 2012 in Beijing, China to measure the rates of incident HIV and identify risk factors for infection. Among 5,800 participants evaluated at enrollment, we identified 486 prevalent cases of HIV (8.4%). Among the 3,625 enrollees who were HIV-negative at enrollment and completed at least one follow-up interview, we identified 440 incident cases of HIV in the follow up period: this constituted an HIV incidence rate of 7.1 per 100 person-years (95% CI: 6.4-7.7). Early treatment of syphilis may have significantly reduced risk of HIV infection (RR: 1.45, 95% CI: 1.11-1.93), while MSM presenting perfect compliance in the cohort did not show reduction in HIV infection. Our study suggested that HIV incidence has been remained high in this sample of Chinese MSM during the intensive preventive intervention, suggesting that we need to find new strategies to prevent HIV infection in this population.

[The relationship between cellular infection by Hantaan virus and expression of beta3 integrin].

OBJECTIVE: To investigate the relationship between cellular entry of Hantaan virus (HTNV) and expression of beta3 integrin in beta3-integrin-deficient and HTNV-insusceptible China hamster ovary (CHO) cells. METHODS: Eukaryotic expression vector encoding human integrin beta3 and eukaryotic expression vector harboring human integrin alphav or alphaIIb subunit cDNA were transfected into HTNV non-permissive CHO cells individually or collectively. Screening for stable transfectant clones was performed using G418 selective (culture medium. The exogenous gene expression was analyzed qualitatively and quantitatively by immunofluorescence assay (IFA) and flow cytometry (FCM). Various modified CHO cells and untransfected CHO cells were infected using HTNV A9. At various time points after infection, HTNV antigens in infected cells were detected qualitatively and quantitatively by IFA, FCM. RESULTS: Highly-effective surface expression of beta3 integrin was measured in CHO/alphavbeta3 and CHO/alphaIIbbeta3, while weaker surface expression was detected in CHO/beta3 (P < 0.05). Expression of alphav or alphaIIb integrin in the individually transfected group was significantly lower than in the cotransfected group (P < 0.01) and the sites of localization changed. In contrast, effective surface expression was not seen when pcDNA3 was transfected alone. The infection rate of CHO/alphavbeta3 (60.1%) and CHO/alphaIIbbeta3 (55. 9%) cells were significantly higher than that of CHO/beta3 (38.7%) cells, while the infection rate of CHO/beta3 was significantly higher than that of CHO/alphav, CHO/pcDNA3 and CHO cells respectively. There was a close relationship between the positive percentage of HTNV A9-infected cells and expression of beta3 integrin. CONCLUSION: These results indicated that cellular entry of HTNV was related to the expression of beta3 integrin.

[Spinal cord neuronal apoptosis induced by triorthocresyl phosphate poisoning in hens].

OBJECTIVE: To investigate the role of neuronal apoptosis in organophosphorus poisoning-induced delayed neuropathy (OPIDN) and its dynamic pathological changes. METHODS: To establish OPIDN animal model, triorthocresyl phosphate (TOCP)was given to hens with a single dose (1 000 mg/kg, im). Changes of neuropathology, number of neurons and apoptotic cells in the third lumbar spinal cord were observed by HE, Nissl and TUNEL methods 3, 5, 7, 10, 14, 18 days after injection. RESULTS: The hens showed OPIDN typical signs (progressive ataxia and hypotonia) about 9 days after TOCP exposure. HE staining revealed dark red nucleus in neurons of anterior horn of lumbar spinal cord 5 days after exposure, but this phenomenon disappeared 18 days later. Nissl method showed that the number of neurons in anterior horn of spinal cord decreased [from (82 +/- 4) cell/mm(2) to (66 +/- 6) cell/mm(2)]. TUNEL positive cells began to appear [(22 +/- 2) cell/mm(2)] 5 days after TOCP exposure, and reached the peak [(27 +/- 3) cell/mm(2)] 7 days later, and disappeared 18 days later. CONCLUSION: Neuronal apoptosis in anterior horn of spinal cord of hens appeared in OPIDN, suggesting that cellular apoptosis may play an important role in the pathogenesis of OPIDN.

A rapid lateral fluid percussion injury rodent model of traumatic brain injury and post-traumatic epilepsy.

Traumatic brain injury is a leading cause of acquired epilepsy. Initially described in 1989, lateral fluid percussion injury (LFPI) has since become the most extensively used and well-characterized rodent traumatic brain injury and post-traumatic epilepsy model. Universal findings, particularly seizures that reliably develop after an initial latent period, are evident across studies from multiple laboratories. However, the LFPI procedure is a two-stage process, requiring initial surgical attachment of a skull fluid cannula and then reanesthesia for delivery of the epidural fluid pressure wave. We now describe a modification of the original technique, termed 'rapid lateral fluid percussion injury' (rLFPI), which allows for a one-stage procedure and thus shorter operating time and reduced anesthesia exposure. Anesthetized male Long-Evans rats were subjected to rLFPI through a length of plastic tubing fitted with a pipette tip cannula with a 4-mm aperture. The cannula opening was positioned over a craniectomy of slightly smaller diameter and exposed dura such that the edges of the cannula fit tightly when pressed to the skull with a micromanipulator. Fluid percussion was then delivered immediately thereafter, in the same surgery session. rLFPI resulted in nonlethal focal cortical injury in all animals. We previously demonstrated that the rLFPI procedure resulted in post-traumatic seizures and regional gliosis, but had not examined other histopathologic elements. Now, we show apoptotic cell death confined to the perilesional cortex and chronic pathologic changes such as ipsilesional ventriculomegaly that are seen in the classic model. We conclude that the rLFPI method is a viable alternative to classic LFPI, and--being a one-stage procedure--has the advantage of shorter experiment turnaround and reduced exposure to anesthetics.

Hippocampal immediate early gene transcription in the rat fluid percussion traumatic brain injury model.

Traumatic brain injury (TBI) is one of the leading causes of neurological disability and death in the USA across all age groups, ethnicities, and incomes. In addition to the short-term morbidity and mortality, TBI leads to epilepsy and severe neurocognitive symptoms, both of which are referenced to post-traumatic hippocampal dysfunction, although the mechanisms of such hippocampal dysfunction are incompletely understood. Here, we study the temporal profile of the transcription of three select immediate early gene (IEG) markers of neuronal hyperactivation, plasticity, and injury, c-fos, brain-derived neurotrophic factor (BDNF), and Bax, in the acute period following the epileptogenic lateral fluid percussion injury in a rodent TBI model. We found that lateral fluid percussion injury leads to enhanced expression of the selected IEGs within 24 h of TBI. Specifically, BDNF and c-fos increase maximally 1-6 h after TBI in the ipsilesional hippocampus, whereas Bax increases in the hippocampus bilaterally in this time window. Antagonism of the N-methyl-D-aspartate-type glutamate receptor by MK801 attenuates the increase in BDNF and Bax, which underscores a therapeutic role for N-methyl-D-aspartate-type glutamate receptor antagonism in the acute post-traumatic time period and suggests a value to a hippocampal IEG readout as an outcome after injury or acute therapeutic intervention.