In vitro immunomodulatory activity of celastrol against influenza A virus infection

Context: The influenza A virus (IAV) causes severe respiratory disease that remains a leading reason for morbidity and mortality. Previous studies have indicated that influenza complications in addition to viral replication are due to overproduction of pro-inflammatory cytokines. Therefore, a new compound is needed to be used with current antiviral drugs to modulate overproduction of pro-inflammatory cytokines in IAV infection.

Objective: This study investigated the effect of celastrol on mRNA expression and concentration levels of the pro-inflammatory cytokines tumor necrosis factor alpha (TNFα) and interleukin-6 (IL6) that are induced by influenza A/Puerto Rico/8/34 (H1N1; PR8) in Madin-Darby Canine Kidney (MDCK) cells. The effect of this compound on virus titration and viral mRNA expression was also investigated.

Methods: Confluent MDCK cells were infected with influenza virus (H1N1; PR8) and treated with celastrol at different concentrations. After incubation, mRNA expression and concentrations of TNFα and IL6 were investigated using real-time polymerase chain reaction (PCR) and ELISA. The viral mRNA expression and virus titration were investigated using real-time PCR and 50% tissue culture infectious dose (TCID₅₀) assay, respectively.

Results: mRNA expression and concentrations of TNFα and IL6 increased significantly in control virus compared to cell control, and decreased significantly when compared with control virus after celastrol treatment. Viral mRNA expression and virus titration did not decrease after celastrol treatment.

Conclusion: Due to reducing mRNA expression and concentrations of TNFα and IL6, celastrol can serve as a suitable choice to control cytokine-induced inflammation in IAV infection, and therefore it can be used with current antiviral drugs.     

Natural type 1 interferon producing cells in HIV infection

Natural type 1 interferon producing cells (IPCs) are in the first line of defense against infectious pathogens. Besides the known properties of type 1 interferons in inhibiting human immunodeficiency virus (HIV) replication, the recent characterization of human IPCs and the possibility to purify them for in vitro studies has greatly accelerated the study of their role in HIV infection. The blood IPC numbers and function are decreased in HIV primary infection and in advanced stages of HIV infection. Loss of circulating IPCs correlates with a high HIV viral load and the occurrence of opportunistic infections. Moreover, HIV can directly infect IPCs in vitro, providing a potential explanation for their in vivo depletion. Thus, the balance between IPCs and HIV replication might be critical in determining the control or progression of HIV infection.     

RNAi在HIV感染中的作用

RNAi,作为一种调控特定基因表达的手段,被称为基因组的免疫现象,已成为最近生物医学领域的研究焦点之一。在机体抵抗病毒感染中,RNAi是一种基因水平上的有效的保护性机制。本文就RNAi机制在抵御HIV感染中的研究进展进行了综述。     

台山市HIV／AIDS配偶间感染状况分析

目的了解台山市HIV感染者／病人配偶间HIV感染状况,为制定有效干预措施提供科学依据。方法从艾滋病综合防治信息管理系统筛选出2012年存活可随访到的现住址为台山市、有配偶且配偶为阴性或阳性的HIV／AIDS病例资料,建立数据库进行分析。结果共有164对HIV双阳或单阳配偶,HIV双阳率为61．59％（101／164）,HIV单阳率38．41％（63／164）。男方HIV感染阳性率为58．11％,高于女方的41．89％,差异有统计学意义（X2=13．95,P〈0．01）,30～39岁年龄段的人数最多占49．06％（130／265）。传播途径为注射毒品感染占80．49％（132／164）。配偶中以男方先检出的占64．63％（106／164）,其中52．83％为羁押场所检出,而以女方为先检出的配偶中47．73％为孕产期检查检出。双阳配偶中。44．55％的夫妻检测阳性时间间隔在3个月以内。单阳家庭接受抗病毒治疗的比例比双阳家庭高,差异有统计学意义（X2=38．88,P〈0．01）。结论台山市配偶间HIV传播率较高,开展监测早期发现感染者。加强30～39岁年龄段人群干预工作力度,是阻断家庭内性传播的重点工作。     

Immunophenotypic alterations in acute and early HIV infection

To understand the extent of immune dysregulation in primary HIV infection (PHI) and the impact of antiretroviral therapy (ART) on restoring these abnormalities, we longitudinally evaluated 52 subjects (Acute-Treated (AT); Early-Treated (ET); Early Untreated (EU)) for markers of activation, proliferation, and function on T cells. ET and AT patients differed by 0.54 log viral load (VL) at baseline but did not differ thereafter by more than 0.34 log10 VL. AT subjects had higher CD8(+) T cell counts and expression of markers indicative of CD8(+) T cell activation (CD38), and proliferation (Ki67), at baseline, than ET subjects but were not different 48 weeks post-ART. Although acute PHI is marked by higher level of immune activation than early PHI, virologic and immunologic responses were similar post-ART, suggesting that the extent of immunologic recovery is not negatively impacted by a delay of treatment beyond the acute stage of disease.     

Isolation of human immunodeficiency virus (HIV) from plasma during primary HIV infection

Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.     

Iron status and the outcome of HIV infection: an overview

BACKGROUND: Theoretical considerations and experiments in the laboratory suggest that excessive iron stores may have an adverse effect on immunity. If so, high iron stores might be especially a problem in patients with human immunodeficiency virus (HIV) infection. OBJECTIVE AND STUDY DESIGN: Review published clinical studies that provide information regarding the effect of iron status on the outcome of HIV infection. RESULTS: Four clinical observations have provided some perspective on the effect of iron status on the outcome of HIV-1 infection. First, in a retrospective study of HIV-positive thalassemia major patients, the rate of progression of HIV disease was significantly faster in patients with lower doses of desferrioxamine and higher serum ferritin concentrations. Second, the inadvertent simultaneous administration of low doses of oral iron with dapsone for the prophylaxis of Pneumocystis carinii pneumonia in HIV-positive patients may have been associated with excess mortality. Third, a study of haptoglobin polymorphisms in HIV-positive subjects indicated that the haptoglobin 2-2 polymorphism is associated with higher iron stores and shortened survival as compared with the haptoglobin 1-1 or 2-1 phenotypes. Fourth, a retrospective study of bone marrow macrophage iron in HIV-positive patients suggested that survival is shorter with high iron stores. CONCLUSION: These four observations raise the possibility that high iron status may adversely influence the outcome of HIV-1 infection.     

Disturbed immunoregulatory properties of the neuropeptide substance P on lymphocyte proliferation in HIV infection.

The neuropeptide substance P (SP) is known to increase cell-mediated immune responses in animal models and healthy subjects. Several studies have suggested an involvement of neuropeptides in the immunopathogenesis of some diseases. The study of the immunomodulatory effects of neuropeptides, namely SP, may represent a model for the analysis of immunoregulatory defects in HIV infection at the level of the interaction between the immune and nervous systems, both of which are known to be affected by the virus. In the present study, we investigate the possibility of a disturbance in the immunomodulatory properties of SP in HIV infection by analysing the effects of SP (10(-10)-10(-6) M) on the lymphocyte proliferative responses to concanavalin A (Con A) and phytohaemagglutinin (PHA) assessed by 3H-thymidine incorporation in peripheral blood lymphocytes from 34 HIV-infected patients (16 asymptomatic (ASY)/persistent generalized lymphadenopathy (PGL); 18 ARC/AIDS) and in 37 healthy subjects. In ASY/PGL HIV-infected patients, SP 10(-7) M was identified as the concentration inducing the maximal increase in the lymphocyte responses to Con A and PHA, similarly to what was observed in healthy subjects. In ARC/AIDS patients, SP appeared to inhibit the mitogenic responses, particularly those induced by Con A, in contrast to the effects found either in healthy subjects or in ASY/PGL patients. These results suggest the existence of an alteration in the in vitro immunomodulatory properties of SP in ARC/AIDS patients compared with healthy subjects and ASY/PGL patients. In conclusion, the unexpected finding of an inhibitory effect of SP on lymphocyte proliferation from ARC/AIDS patients justifies further investigation of the neuropeptide-dependent immunoregulatory systems in HIV infection.     

Persistent productive HIV infection in EBV-transformed B lymphocytes

The susceptibility to HIV infection of 14 B-cell lines established from five healthy HIV seronegative and from six HIV seropositive subjects by lymphocyte transformation with EBV and/or by lymphocyte cultivation with cyclosporin A was studied. Although the cell lines contained different proportions of CD4-positive cells, as shown by flow cytometry, all of them could be infected with the SF-2 strain of HIV. Infection was blocked by a monoclonal antibody directed against the viral attachment site of the CD4 molecule, even in a line that lacked demonstrable CD4 receptors. B-cell lines with high proportions of CD4-expressing cells produced HIV p24 antigen more rapidly and at higher concentrations than cell lines with low CD4 expression. Although HIV infection resulted in some cytopathic effects, it was possible to cultivate the infected cells for more than 8 months without refeeding the cultures with uninfected cells. Even in long-term cultures, there was a continuous production of infectious HIV, as detected by transfer of culture supernatants to other susceptible cell lines. The production of viral antigens was consistently more pronounced in the B-cell line with the highest CD4 positivity than it was in a permissive T-cell line (HUT-78) infected in the same manner. These results indicate that HIV can chronically and productively infect transformed B cells via interaction with CD4 molecules. Thus it is possible that B cells may constitute a source of infectious virus in HIV-infected EBV-positive individuals.     

B-cell responses to HIV infection

The induction of neutralizing antibodies directed against the human immunodeficiency virus (HIV) has received considerable attention in recent years, in part driven by renewed interest and opportunities for antibody-based strategies for prevention such as passive transfer of antibodies and the development of preventive vaccines, as well as immune-based therapeutic interventions. Advances in the ability to screen, isolate, and characterize HIV-specific antibodies have led to the identification of a new generation of potent broadly neutralizing antibodies (bNAbs). The majority of these antibodies have been isolated from B cells of chronically HIV-infected individuals with detectable viremia. In this review, we provide insight into the phenotypic and functional attributes of human B cells, with a focus on HIV-specific memory B cells and plasmablasts/cells that are responsible for sustaining humoral immune responses against HIV. We discuss the abnormalities in B cells that occur in HIV infection both in the peripheral blood and lymphoid tissues, especially in the setting of persisting viremia. Finally, we consider the opportunities and drawbacks of intensively interrogating antibodies isolated from HIV-infected individuals to guide strategies aimed at developing effective antibody-based vaccine and therapeutic interventions for HIV.     

外科手术中HIV/AIDS病毒医源性感染的防护分析

目的 分析外科手术中HIV/AIDS病毒医源性感染的状况,以控制医源性感染.方法 收集2010年1月至2013年1月广西钦州市第一人民医院普外科收治的12例HIV/AIDS感染的外科手术患者临床资料,观察手术后医务人员的HIV/AIDS医源性感染状况,探讨预防医源性感染的措施.结果 参与患者手术的医务人员术后未出现HIV/AIDS病毒医源性感染者.结论 加强医务人员自我保护意识,定期进行知识和技能培训是防止HIV/AIDS病毒医源性感染的有效途径.     

Acute HIV infection: the impact of anti-retroviral treatment on cellular immune responses

The overall value of initiating anti-retroviral therapy during the acute phase of human immunodeficiency virus type 1 (HIV-1) infection remains unclear. From a clinical perspective, the lack of data from controlled randomized clinical trials limits understanding of long-term effects of treatment on the clinical course of HIV infection. Based on available data, the impact of anti-retroviral therapy during acute infection on the immune response against HIV-1 is not particularly encouraging. Recent observations on the very early depletion of lymphocyte reservoirs in the gastrointestinal tract may partially explain the limited benefit of anti-retroviral therapy initiated during the acute phase of HIV-1 infection. This may also help to explain the dichotomy between early observations demonstrating apparent immunological benefit with early anti-retroviral treatment that were associated none the less with inability to control viral replication following treatment interruption.     

Cell-mediated immune responses to mycobacterial antigens in patients with pulmonary tuberculosis and HIV infection

Lymphocyte proliferation and cytokine responses induced by a panel of mycobacterial antigens were compared in Portuguese donors with pulmonary tuberculosis (TB) with or without HIV co-infection, HIV⁺ patients and healthy Mantoux-positive controls. Control donors showed stronger proliferative responses than any of the patient groups, with secreted antigens (Mycobacterium tuberculosis (Mtb) 30 kD and short-term culture filtrate proteins (ST-CFP)), purified protein derivative (PPD) and Mtb H37Rv Sonicate (MtbS) inducing the strongest proliferation. Patients with pulmonary TB showed lower proliferation to PPD or to the 30-kD antigen. Responses to all the antigens (PPD, ST-CFP, MtbS, 70 kD, 65 kD, 38 kD, 30 kD and 10 kD) were higher in TB/HIV patients with CD4 counts 200 CD4⁺ T cells/mm³ compared with HIV alone (CD4 200 T cells/mm³), but were lost in both TB/HIV and HIV patients when CD4 counts fell below 200 T cells/mm³. Measurements of interferon-gamma (IFN-γ) in culture supernatants revealed that PPD, 30 kD, MtbS and ST-CFP induced the strongest Th1 response. Analysis of mRNA for IFN-γ, IL-4 and IL-10 confirmed that IFN-γ production was maintained in patients with pulmonary TB without any concomitant increase in IL-4 or IL-10 mRNA expression, although expression of IL-10 mRNA was increased if HIV infection was present. These results reveal that IFN-γ production is retained in pulmonary TB patients to a broad range of mycobacterial antigens, and that no switch to IL-4 production is seen even with HIV infection. Secreted antigens, and in particular ST-CFP, were the best inducers of IFN-γ secretion, confirming their role in protective responses to Mtb.     

HIV感染与细胞焦亡

目前艾滋病(AIDS)被认为是一种慢性疾病。炎症和免疫活化在疾病进展中起了重要作用。细胞焦亡是HIV感染过程中造成CD4^+T细胞死亡的主要程序性细胞死亡方式,并伴随着IL-1β等促炎因子和细胞内容物的释放,引起机体炎症反应。细胞焦亡联系起了HIV感染过程中的CD4^+T细胞死亡和炎症反应发生这2个最主要的病理事件。因此,抑制细胞焦亡可能对艾滋患者的治疗有重要意义。本文综述了HIV感染过程中细胞焦亡的发生及其引起的病理性事件,为探索艾滋病患者治疗新策略提供线索。     

HIV感染合并IgA肾病4例临床和病理分析

目的 研究HIV感染合并IgA肾病患者的临床和病理特点及治疗转归.方法 选择2002-2012年在北京协和医院住院的HIV感染合并肾脏损害,并经肾脏活检证实为IgA肾病的4例患者为研究对象,回顾分析这4例IgA肾病患者的临床、病理资料及治疗随诊情况.结果 4例患者均有不同程度蛋白尿和镜下血尿,血肌酐水平在正常范围,肾脏活检病理提示为不同程度的IgA肾病.4例患者均接受了高效联合抗反转录病毒治疗(HAART).3例患者的初始治疗使用了ACEI/ARB,其中2例效果不佳联合使用糖皮质激素治疗.1例肾脏病变好转后再次出现大量蛋白尿,考虑与抗病毒药物替诺夫韦有关,调整抗病毒治疗后再次缓解.治疗过程中所有患者的HIV病毒复制并未增加.结论 HIV感染合并肾脏病变除了经典塌陷型FSGS之外还可以合并IgA肾病,肾脏活检有利于明确诊断并指导治疗.     

In vitro measurement of cytotoxic T cell activity does not predict clinical progression in paediatric HIV disease—two case studies

Cytotoxic T cells are believed to be an important immune response in HIV infection, both in the initial response to viraemia, and in controlling HIV replication and maintaining clinical stability. We report here the detailed findings in two vertically infected children, from the Edinburgh perinatal cohort. Both were clinically stable for the first 7 years of life. One had vigorous HIV-specific cytotoxic T lymphocyte (CTL) responses, and non-lytic suppression, measured in vitro, while the second had no CTL activity against HIV. Despite her HIV-specific immunity, the first child had a declining CD4 count, and a high and fluctuating viral load, whereas the second child maintained a stable CD4 count, a low viral load and had a virus which could not be cultured in peripheral blood mononuclear cells (PBMC) in vitro. The first child subsequently progressed to AIDS and has now died, while the second remains clinically well. More detailed investigations showed the clinically stable child to be heterozygous for the CCR5 receptor, and to be HLA-B49—both of which markers have been associated with slow HIV disease progression. These findings question the role of CTL in maintaining stable HIV disease, and stress the need for immunological investigations to be considered in the light of the genetic make-up of the patient. They may also reflect a different immunopathogenesis of HIV disease in children compared with adults.     

Study of left ventricular performances in children with HIV infection

Because the reported series of children with cardiac abnormalities are small and contradictory we studied the duration of the systolic phases of the cardiac cycle and ejection fraction in ten children with HIV infection. Recordings of noninvasive systolic time intervals were made from supine patients and at rest. The duration of the phases of cardiac cycle and ejection fraction was measured from simultaneous recordings of the EKG, PCG and carotid arterial pulse. Results show that cardiovascular abnormalities are common in children with HIV infection; the changes in left ventricular performances occurring during the duration of the disease appear at times even before the clinical symptoms.     

Differential isotype expression and binding properties of T cell-reactive antibodies in human immunodeficiency virus (HIV) infection

Isotype and binding characteristics of T cell-reactive antilymphocyte antibodies (ALA) were investigated in 287 human immunodeficiency virus (HIV)⁺ sera from patients with CDC II to IVC clinical disease. Using purified soluble T-lymphoblast (CEM cell line) membranes and an ELISA method, 29 HIV⁺ sera showed significant reactions with this substrate and a selective expression of IgG-ALA was detected in 7 HIV⁺ sera. Subsequent microcytotoxicity assays, utilizing peripheral T lymphocytes and CEM cells as targets, demonstrated no significant cytotoxic capability in such sera, whereas 12 of 17 HIV⁺ serum samples with IgM-ALA ELISA reactivities showed a significant degree of killing in the Terasaki test. Further experiments of saturation of CD4 molecules on CEM extract by OKT4 monoclonal antibody (MoAb) induced a high inhibition of IgG-ALA binding to the T-cell membranes in only two IgG-ALA⁺ sera (No. 93, CDC III; No. 179, CDC II stage). Conversely, treatment of CEM membrane lysate with Leu3a MoAb, specific for the gp120 reactive domain of the HIV receptor, failed to prevent membrane binding in all seven of the IgG-ALA⁺ sera. Following the adsorption of serum 93 on a T-cell membrane antigen affinity column, SDS-PAGE analysis demonstrated that the predominant ALA material reacting with T-cell membranes was IgG with no detectable traces of IgM. These data provide evidence that ALA in HIV⁺ patients may be simultaneously or selectively expressed as IgG and/or IgM with different properties. While IgM-ALA show predominant cytotoxic activity, IgG-ALA may include anti-CD4 molecules. However, IgG binding to the C-terminal domain of native HIV receptor appears to occur at a lower rate than IgM-ALA in HIV infection.     

Anti-neutrophil cytoplasmic autoantibodies in patients with symptomatic HIV infection.

Antibodies against cytoplasmic antigens of neutrophils, producing perinuclear (p-ANCA) as well as cytoplasmic staining with central accentuation (c-ANCA), have been described in non-HIV-infected patients with specific pathology such as glomerulonephritis and vasculitis. Here, we report on a patient with a vasculitis-like syndrome and a positive ANCA-test who appeared to be infected by HIV. Further analysis revealed that ANCA, p-ANCA as well as c-ANCA without central accentuation can be demonstrated in the serum of HIV+ individuals. In a cross-sectional study on individuals in different stages of HIV infection, we found that the occurrence of ANCA was limited to the symptomatic stages of HIV infection: p-ANCA was found in one out of 10 ARC patients and in two out of 11 AIDS patients with malignancies (AIDS-MAL), but not in AIDS patients with opportunistic infections (AIDS-OI). c-ANCA was found in four of the ARC patients, in two of the 14 AIDS-OI patients and in two AIDS-MAL patients. The presence of ANCA was not related to the degree of hypergammaglobulinaemia nor to specific symptomatology. ANCA containing sera from HIV+ individuals did not react with HEp2 cells nor with cytoplasmic antigens of lymphocytes, natural killer (NK) cells or eosinophils. Five out of the 11 (two p-ANCA and three c-ANCA) sera reacted weakly with cytoplasmic antigens of monocytes. All sera reacted with karyoplasts but not with cytoplasts prepared from neutrophils. These results suggest that HIV-ANCA might be directed against myeloid cell-specific granule constituents. However, sandwich-ELISAs with MoAbs against granule antigens that are frequently the target antigens of ANCA in HIV- individuals were negative. Also immunoprecipitation and immunoblotting, using lysates of neutrophil granules, did not allow further identification of the target antigens of HIV-ANCA.