Molecular pathogenesis of human immunodeficiency virus infection

Molecular studies of the pathogenesis of human immunodeficiency virus (HIV) infections have proceded rapidly following the molecular cloning and nucleotide sequence analysis of the HIV genome. Correlation of biochemical and functional studies of HIV-infected cells with the HIV nucleotide sequence has allowed the identification and preliminary functional characterization of many HIV proteins. These include structural proteins (gag), viral enzymes (pol), and viral regulatory proteins (tat, art). Cloned HIV DNA segments have been utilized as probes for in situ nucleic acid hybridization to study the distribution of HIV-infected cells in acquired immunodeficiency syndrome (AIDS) and AIDS-related complex (ARC) patients. These studies have demonstrated the infection of macrophages as an important component of HIV-induced neurologic disease. Only very low numbers of HIV-infected lymphocytes can be identified in the peripheral blood of infected individuals. Thus, the mechanism of CD4 cell depletion in the pathogenesis of AIDS remain obscure.     

Infection of insect cell lines by the HIV virus, an agent of AIDS, and a demonstration of insects of African origin infected by this virus

The etiological agent of AIDS known as HIV has been shown to bind on different insect cell lines including Drosophila, Mosquito, Ceratitis; and his DNA to be integrated in the cellular genome, but no expression of the viral genome was detected in those cells. None of the human lymphocytes markers is expressed at the surface of the insect cells. HIV proviral DNA has been also found in various insects from Central Africa (Za?re and Central Africa Republic) but not similar insects from the Paris area. These data suggest that insects could be a reservoir or a vector for the AIDS virus.     

Biochemical deficiencies of coenzyme Q10 in HIV-infection and exploratory treatment

AIDS patients (2 groups) had a blood deficiency (p less than 0.001) of coenzyme Q10 vs. 2 control groups. AIDS patients had a greater deficiency (p less than 0.01) than ARC patients. ARC patients had a deficiency (p less than 0.05) vs. control. HIV-infected patients had a deficiency (p less than 0.05) vs. control. The deficiency of CoQ10 increased with the increased severity of the disease, i.e., from HIV positive (no symptoms) to ARC (constitutional symptoms, no opportunistic infection or tumor) to AIDS (HIV infection, opportunistic infection and/or tumor). This deficiency, a decade of data on CoQ10 on the immune system, on IgG levels, on hematological activity constituted the rationale for treatment with CoQ10 of 7 patients with AIDS or ARC. One was lost to follow-up; one expired after stopping CoQ10; 5 survived, were symptomatically improved with no opportunistic infection after 4-7 months. In spite of poor compliance of 5/7 patients, the treatment was very encouraging and at times even striking.     

Evaluation of Epstein-Barr Virus Salivary Shedding in HIV/AIDS Patients and HAART Use: A Retrospective Cohort Study

Little data is available on the evaluation of the occurrence rates of Epstein-Barr virus(EBV) in saliva and relationship with highly active antiretroviral therapy(HAART) use in HIV/AIDS patients in China. We conducted a retrospective cohort study of EBV serological tests for HIV/AIDS patients who were treated in the hospitals for infectious diseases in Wuxi and Shanghai, China from May 2016 to April 2017. The EBV-seropositive samples were identified by ELISA. EBV-specific primers and probes were used for the quantitative detection of viral DNA from saliva via quantitative real-time polymerase chain reaction. CD4 cell counts of the HIV/AIDS patients were detected by a flow cytometry. A total of 372 HIV/AIDS patients were ultimately selected and categorized for this retrospective cohort study. For EBV IgG and IgM, the HIV/AIDS HAART use(H) and non-HAART use(NH) groups had significantly higher seropositive rates than the HIV-negative control group. The HIV/AIDS(NH) group had the highest seropositive rate(IgG, 94.27%; IgM, 68.98%) and the highest incidence of EBV reactivation or infection. For salivary EBV DNA-positive rates and quantities, the HIV/AIDS(H)(73.69%) and the HIV/AIDS(NH)(100%) groups showed significantly higher values than the HIV-negative control group(35.79%,[ twofold). Further, the salivary EBV DNA-negative population had significantly higher CD4 cell counts than the EBV DNA-positive population in the HIV/AIDS(H) group and the HIV/AIDS(NH) groups. Thus, HAART use is beneficial in decreasing the EBV salivary shedding in HIV/AIDS patients and indirectly decreases EBV transmission risk.     

Declining incidence of AIDS dementia complex after introduction of zidovudine treatment.

OBJECTIVE--To assess the incidence of the AIDS dementia complex and the presence of HIV I p24 antigen in cerebrospinal fluid in relation to zidovudine treatment. DESIGN--Retrospective study of a consecutive series of patients with AIDS from 1982 to 1988. SETTING--An academic centre for AIDS. PATIENTS--196 Patients with AIDS and neurological symptoms examined from 1982 to 1988. INTERVENTIONS--Zidovudine treatment, which was introduced to The Netherlands on 1 May 1987 for patients with severe symptoms of HIV infection (Centers for Disease Control groups IVA, B, C, and D). MAIN OUTCOME MEASURES--Diagnosis of AIDS dementia complex and presence of HIV I p24 antigen in cerebrospinal fluid. RESULTS--The AIDS dementia complex was diagnosed in 40 of the 196 (20%) patients with AIDS. Thirty eight of 107 patients with AIDS (36%) not taking zidovudine developed the AIDS dementia complex compared with two of the 89 (2%) taking the drug (p less than 0.00001). The incidence of the AIDS dementia complex increased to 53% in the first half of 1987, after the introduction of zidovudine in May 1987, decreasing to 10% in the second half of 1987 and to 3% in 1988. Dementia was diagnosed before definition of the AIDS dementia complex (1986) according to DSM-III criteria and there was good agreement between diagnosis before and after 1986. Sixteen of 61 samples of cerebrospinal fluid (26%) from patients with AIDS (10 with the AIDS dementia complex) not taking zidovudine were positive for HIV I p24 antigen, whereas none of 37 cerebrospinal fluid samples from patients with AIDS (two with the AIDS dementia complex) taking zidovudine were positive. CONCLUSIONS--The incidence of AIDS dementia complex in patients with AIDS declined after the introduction of systematic treatment with zidovudine; the AIDS dementia complex might be prevented by inhibiting viral replication in the central nervous system.     

The transmission dynamics of human immunodeficiency virus (HIV)

The paper first reviews data on HIV infections and AIDS disease among homosexual men, heterosexuals, intravenous (IV) drug abusers and children born to infected mothers, in both developed and developing countries. We survey such information as is currently available about the distribution of incubation times that elapse between HIV infection and the appearance of AIDS, about the fraction of those infected with HIV who eventually go on to develop AIDS, about time-dependent patterns of infectiousness and about distributions of rates of acquiring new sexual or needle-sharing partners. With this information, models for the transmission dynamics of HIV are developed, beginning with deliberately oversimplified models and progressing--on the basis of the understanding thus gained--to more complex ones. Where possible, estimates of the model's parameters are derived from the epidemiological data, and predictions are compared with observed trends. We also combine these epidemiological models with demographic considerations to assess the effects that heterosexually-transmitted HIV/AIDS may eventually have on rates of population growth, on age profiles and on associated economic and social indicators, in African and other countries. The degree to which sexual or other habits must change to bring the 'basic reproductive rate', R0, of HIV infections below unity is discussed. We conclude by outlining some research needs, both in the refinement and development of models and in the collection of epidemiological data.     

Coenzyme Q10 increases T4/T8 ratios of lymphocytes in ordinary subjects and relevance to patients having the AIDS related complex.

Coenzyme Q10 (CoQ10) is indispensable to biochemical mechanisms of bioenergetics, and it has a non-specific role as an antioxidant. CoQ10 has shown a hematological activity for the human and has shown an influence on the host defense system. The T4/T8 ratios of lymphocytes are known to be low in patients with AIDS, ARC and malignancies. Our two patients with ARC have survived four-five years without any symptoms of adenopathy or infection on continuous treatment with CoQ10. We have newly found that 14 ordinary subjects responded to CoQ10 by increases in the T4/T8 ratios and an increase in blood levels of CoQ10; both by p less than 0.001. This knowledge and survival of two ARC patients for four-five years on CoQ10 without symptoms, and new data on increasing ratios of T4/T8 lymphocytes in the human by treatment with CoQ10 constitute a rationale for new double blind clinical trials on treating patients with AIDS, ARC and diverse malignancies with CoQ10.     

Early effects of HIV on CD4 lymphocytes in vivo

Low circulating CD4 cell numbers and CD4 cell dysfunction are distinguishing features of HIV-mediated disease. The current study delineates the in vivo effects of HIV on distinct functional subsets of CD4 cells in homosexually active men who have been infected with HIV for different lengths of time, and examines the capacity of lymphocytes from these men to proliferate in vitro in response to soluble antigen. Although peripherial blood mononuclear cells from most acquired immune deficiency syndrome (AIDS) patients did not proliferate in response to either tetanus toxoid or Candida albicans, cells from most HIV seropositive men without AIDS, many of whom had been infected for more than 18 mo, responded normally to both. Non-responsiveness in HIV-infected men without AIDS was a late event and was associated with longer duration of infection, lower CD4 cell numbers, and subsequent development of AIDS. A defect in this response was observed in only one of 19 HIV seropositive men whose CD4 levels were greater than 300/mm3, but in eight of 10 with levels less than 300/mm3. The defect could not be attributed to a selective depletion of defined CD4 subpopulations that respond to soluble antigen. Dual-color immunofluorescent flow cytometry indicated that 4B4+, 2H4-, and HB-11- CD4 cells were not lost at a faster rate than other CD4 subsets.     

Virally induced CD4+ T cell depletion is not sufficient to induce AIDS in a natural host

Peripheral blood CD4+ T cell counts are a key measure for assessing disease progression and need for antiretroviral therapy in HIV-infected patients. More recently, studies have demonstrated a dramatic depletion of mucosal CD4+ T cells during acute infection that is maintained during chronic pathogenic HIV as well as SIV infection. A different clinical disease course is observed during the infection of natural hosts of SIV infection, such as sooty mangabeys (Cercocebus atys), which typically do not progress to AIDS. Previous studies have determined that SIV+ mangabeys generally maintain healthy levels of CD4+ T cells despite having viral replication comparable to HIV-infected patients. In this study, we identify the emergence of a multitropic (R5/X4/R8-using) SIV infection after 43 or 71 wk postinfection in two mangabeys that is associated with an extreme, persistent (>5.5 years), and generalized loss of CD4+ T cells (5-80 cells/microl of blood) in the absence of clinical signs of AIDS. This study demonstrates that generalized CD4+ T cell depletion from the blood and mucosal tissues is not sufficient to induce AIDS in this natural host species. Rather, AIDS pathogenesis appears to be the cumulative result of multiple aberrant immunologic parameters that include CD4+ T cell depletion, generalized immune activation, and depletion/dysfunction of non-CD4+ T cells. Therefore, these data provide a rationale for investigating multifaceted therapeutic strategies to prevent progression to AIDS, even following dramatic CD4 depletion, such that HIV+ humans can survive normal life spans analogous to what occurs naturally in SIV+ mangabeys.     

High‐level expression of human immunodeficiency virus antigens from the tobacco and tomato plastid genomes

Transgene expression from the plant's plastid genome represents a promising strategy in molecular farming because of the plastid's potential to accumulate foreign proteins to high levels and the increased biosafety provided by the maternal mode of organelle inheritance. In this article, we explore the potential of transplastomic plants to produce human immunodeficiency virus (HIV) antigens as potential components of an acquired immunodeficiency syndrome (AIDS) vaccine. It is shown that the HIV antigens p24 (the major target of T‐cell‐mediated immune responses in HIV‐positive individuals) and Nef can be expressed to high levels in plastids of tobacco, a non‐food crop, and tomato, a food crop with an edible fruit. Optimized p24‐Nef fusion gene cassettes trigger antigen protein accumulation to up to approximately 40% of the plant's total protein, demonstrating the great potential of transgenic plastids to produce AIDS vaccine components at low cost and high yield.     

The relationship between virologic and immunologic responses in AIDS clinical research using mixed-effects varying-coefficient models with measurement error

In this article we study the relationship between virologic and immunologic responses in AIDS clinical trials. Since plasma HIV RNA copies (viral load) and CD4+ cell counts are crucial virologic and immunologic markers for HIV infection, it is important to study their relationship during HIV/AIDS treatment. We propose a mixed-effects varying-coefficient model based on an exploratory analysis of data from a clinical trial. Since both viral load and CD4+ cell counts are subject to measurement error, we also consider the measurement error problem in covariates in our model. The regression spline method is proposed for inference for parameters in the proposed model. The regression spline method transforms the unknown nonparametric components into parametric functions. It is relatively simple to implement using readily available software, and parameter inference can be developed from standard parametric models. We apply the proposed models and methods to an AIDS clinical study. From this study, we find an interesting relationship between viral load and CD4+ cell counts during antiviral treatments. Biological interpretations and clinical implications are discussed.     

Attitudes towards HIV/AIDS among four year medical students at the University of Zagreb Medical School--better in 2002 than in 1993 but still unfavorable

Fourth-year medical students at Zagreb University School of Medicine were surveyed about their knowledge and attitudes regarding HIV/AIDS in 2002/03 and this was compared to a student generation studying during 1993/94. Results indicated that the 2002/03 students scored significantly higher then did 1993/94 students on knowledge, and attitudes towards HIV/AIDS. However, 84% of 2002/03 students believed that health care workers (HCW) have the right to know the HIV status of their patients, 50% would disclose the HIV status to another HCW against patient's wishes and only 35% believed that HIV testing should be voluntary. The following factors were independently associated with a more favorable attitude towards HIV/AIDS: less homophobia (beta = -0.37, p < 0.001), experience with HIV/AIDS patients (beta = 1.02, p < 0.001), better knowledge about transmission (beta = 0.18, p = 0.016), and 2002/03 academic year (beta = -1.45, p = 0.011). Despite improvements, some negative attitudes towards HIV/AIDS remained prevalent in 2002/03.     

Double blind dose-response study of zidovudine in AIDS and advanced HIV infection. Nordic Medical Research Councils' HIV Therapy Group.

OBJECTIVE--To compare the efficacy and side effects of 400 mg, 800 mg, and 1200 mg zidovudine daily in patients with AIDS or advanced HIV infection. DESIGN--Randomised, double blind, parallel group multicentre study. SETTING--Hospital departments of infectious diseases and dermatology in Denmark, Sweden, Norway, Finland, and Iceland. SUBJECTS--474 patients: 126 (27%) with AIDS; 248 (52%) with HIV related symptoms; 100 (21%) with low CD4+ cell counts. INTERVENTIONS--Zidovudine 400 mg (160 patients), 800 mg (158), or 1200 mg (156) daily. All patients received one capsule from each of three bottles four times daily. MAIN OUTCOME MEASURES--Survival; incidence of new HIV related events; CD4+ cell count; quality of life; incidence of haematological side effects. RESULTS--460 (97%) of the 474 patients had not received zidovudine previously. The median follow up period was 19 months, during which the death rates in the three treatment groups were 23% (36/160 patients), 23% (36/158), and 19% (30/156) respectively (p = 0.49; log rank test). One year after the trial was terminated the death rates were 38% (61/160), 41% (64/158), and 44% (68/156) respectively (p = 0.54). There was no significant difference between the groups in time to a new AIDS defining event or death, average number of events per patient, decline in CD4+ cell counts, wellbeing (visual analogue scale), or Karnofsky score. Zidovudine was withdrawn in 132 (28%) patients, mainly because of side effects (71 cases; 15%). The incidences of anaemia and leucopenia, time to first dose reduction, and numbers of patients withdrawn were all dose related. CONCLUSION--Zidovudine should be limited to 400-600 mg daily in patients with AIDS or advanced HIV infection.     

The Progress on the Studies of HIV/AIDS Vaccine

人类控制HIV感染长远的目标是发展安全、有效、廉价的HIV AIDS疫苗。但经 2 0多年的努力 ,人类探索HIV AIDS疫苗之路仍在继续。分析了疫苗研究的复杂性和发展HIV AIDS疫苗过程中所面临的挑战 ,并对发展HIV AIDS疫苗的可能性从实验和临床方面进行了阐述。同时结合HIV感染的免疫应答原理对现有的各种HIV AIDS疫苗研究策略作一综述 ,并根据以往HIV AIDS疫苗研究的经验和教训提出未来疫苗的发展思路及展望。     

A Study of Two Procedures of HIV-1 Isolation from Whole Blood Cultures

Culture techniques for isolation of HIV-1 from small amounts of whole blood (WB) treated with anticoagulant have been reported and gave results identical to those of culture of separated peripheral blood mononuclear cells. Some authors obtained much higher isolation rates when EDTA was used instead of heparin. We compared two previously described techniques for cultivation of HIV-1 from WB of adult HIV+ patients staged according to the CDC classification. In addition, we assessed the influence of the type of anticoagulant used for the collection of blood in viral replication in cell cultures from whole blood. Small volumes of WB treated with either heparin or EDTA were cocultivated with phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PHA-PBMC) from healthy donors. We used two procedures for WB culture: procedure I, based on the culture of 250 μl of WB with 1 × 10⁶ PHA-PBMC from donors; and procedure II based on the culture of 500 μl of WB with 4× 10⁶ PHA-PBMC from donors. The cocultures were placed in 24-well plates and incubated for as long as 28 days in medium containing interleukin 2 (IL-2). Twice weekly half of the medium was replaced with fresh medium. In procedure II, one million fresh PHA-PBMC from donors was added on the 7th day of culture. The culture supernatant was assayed for the presence of HIV-1 p24 antigen in an enzyme immunoassay. The kinetics of HIV-1 replication in cultures of WB from 7 AIDS patients were similar using procedures I and II. In 8 HIV + patients the isolation rate was higher with heparin- than with EDTA-treated samples. The isolation rate was higher in AIDS patients (n = 8) than in others with both methods. In stage IV patients without AIDS (n = 8) we failed to isolate HIV-1 in 1 patient with procedure I, whereas we succeeded with procedure II. In stage II, HIV-I was isolated in 1 of 4 patients with both methods. HIV was isolated in cultures of WB from patients receiving zidovudine or related nucleoside analogues and in cultures of WB from untreated patients. HIV-1 could not be isolated from WB of patients with more than 400 CD4+ T lymphocytes in their peripheral blood (n=4); however, it was isolated from 14 of 16 patients with less than 400 CD4+ T lymphocytes. Our results suggest that procedure II is more sensitive than procedure I and that heparin is better than EDTA for collecting WB. We showed that the rate of HIV-1 isolation from WB increased in advanced-stage patients. Further studies are needed to define the clinical applications of WB culture.     

Serological diagnosis of paracoccidioidomycosis in HIV-coinfected patients

Paracoccidioidomycosis should be differentiated from other opportunistic diseases in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) patients who live in Latin America. Laboratory investigation can begin with serological tests, which are rapid and efficient. In the present study, double immunodiffusion (DID), counterimmunoelectrophoresis (CIEP) and an enzyme linked immunosorbent assay (ELISA) tests were assessed for the detection of anti-Paracoccidioides brasiliensis antibodies in 40 patients coinfected with HIV. The results were compared to those obtained for 75 non-HIV-infected patients with endemic paracoccidioidomycosis. Anti-P. brasiliensis antibodies were detected in 65% (DID), 79% (CIEP) and 95% (ELISA) of the patients with HIV/AIDS, significantly lower rates than those detected in cases of endemic paracoccidioidomycosis, which were 89%, 99% and 100%, respectively. The reactive sera of HIV-infected patients also showed lower anti-P. brasiliensis antibody titres than those of non-HIV-infected patients. Despite the lower intensity of the specific humoral response, serological tests are useful for the diagnosis of opportunistic paracoccidioidomycosis in the HIV/AIDS population. We suggest optimization of the laboratory diagnosis by combining the ELISA test with CIEP or DID.     

In vivo distribution and cytopathology of variants of human immunodeficiency virus type 1 showing restricted sequence variability in the V3 loop.

The distribution, cell tropism, and cytopathology in vivo of human immunodeficiency virus (HIV) was investigated in postmortem tissue samples from a series of HIV-infected individuals who died either of complications associated with AIDS or for unrelated reasons while they were asymptomatic. Proviral sequences were detected at a high copy number in lymphoid tissue of both presymptomatic patients and patients with AIDS, whereas significant infection of nonlymphoid tissue such as that from brains, spinal cords, and lungs were confined to those with AIDS. V3 loop sequences from both groups showed highly restricted sequence variability and a low overall positive charge of the encoded amino acid sequence compared with those of standard laboratory isolates of HIV type 1 (HIV-1). The low charge and the restriction in sequence variability were comparable to those observed with isolates showing a non-syncytium-inducing (NSI) and macrophage-tropic phenotype in vitro. All patients were either exclusively infected (six of seven cases) or predominantly infected (one case) with variants with a predicted NSI/macrophage-tropic phenotype, irrespective of the degree of disease progression. p24 antigen was detected by immunocytochemical staining of paraffin-fixed sections in the germinal centers within lymphoid tissue, although little or no antigen was found in areas of lymph node or spleen containing T lymphocytes from either presymptomatic patients or patients with AIDS. The predominant p24 antigen-expressing cells in the lungs and brains of the patients with AIDS were macrophages and microglia (in brains), frequently forming multinucleated giant cells (syncytia) even though the V3 loop sequences of these variants resembled those of NSI isolates in vitro. These studies indicate that lack of syncytium-forming ability in established T-cell lines does not necessarily predict syncytium-forming ability in primary target cells in vivo. Furthermore, variants of HIV with V3 sequences characteristic of NSI/macrophage-tropic isolates form the predominant population in a range of lymphoid and nonlymphoid tissues in vivo, even in patients with AIDS.