Immunopathogenesis of the acquired immunodeficiency syndrome

Hypertriglyceridemia in the acquired immunodeficiency syndrome

PURPOSE

A relationship between the induction of hypertriglyceridemia by cytokines and the cachexia seen in chronic infection has been proposed by other investigators. Since patients with the acquired immunodeficiency syndrome (AIDS) often experience progressive tissue wasting, we decided to examine serum lipid levels and body cell mass in patients with AIDS.

PATIENTS AND METHODS

Serum lipid levels and body cell mass were measured in 32 patients with the acquired immunodeficiency syndrome (AIDS), eight asymptomatic subjects who were anti-human immunodeficiency virus (HIV) antibody positive, and 17 heterosexual and homosexual control subjects who did not have antibodies to HIV.

RESULTS

Mean triglyceride concentrations and the prevalence of hypertriglyceridemia (50 percent) were significantly increased in patients with AIDS compared with control subjects (p less than 0.002 and p less than 0.005, respectively), whereas the mean triglyceride levels of HIV-positive subjects were intermediate. There were no differences in cholesterol levels among the three groups. Using total body potassium adjusted for height and age (KHT) as a measure of body cell mass, 16 of 32 patients with AIDS but none of the HIV-positive or control subjects had significant depletion of body cell mass. There was no direct relationship between triglyceride levels and KHT among AIDS or HIV-positive subjects. In patients with AIDS, mean triglyceride levels and the prevalence of hypertriglyceridemia were similar in the presence and absence of wasting.

CONCLUSION

Hypertriglyceridemia is a common finding in AIDS and is independent of the degree of wasting.

Peripheral blood mononuclear cells from AIDS patients release but do not respond to antigen-stimulated NK-activating lymphokines

We have previously shown that streptococcal product (SP) extracted from the culture supernatants of Streptococcus pyogenes ATCC 19615 augments NK activity, partly by inducing the release of soluble factors from mononuclear cells. In this study we use SP as an NK stimulant to investigate the mechanism of NK depression in AIDS. We demonstrate that the NK activity of AIDS patients is lower than normal controls and can be significantly enhanced with SP, although not to control levels. The decreased cytotoxicity in AIDS is not due to a depletion of NK cells, nor to the depletion of lymphokines from CD4 cells that are directly involved in NK cell activation. PBMCs from patients with AIDS respond to SP, producing normal levels of NK-enhancing substances in their supernatants. However, upon examining the ability of SP-induced supernatants from control cells to augment the NK activity of cells from AIDS patients, we find significantly less activity in AIDS cells than in control cells, suggesting an intrinsic effector dysfunction of NK cells in AIDS.

Immunopathogenic mechanisms in human immunodeficiency virus (HIV) infections

Infection with HIV can result in a complex array of immunopathogenic effects. HIV infection involves both a direct quantitative depletion of T4 lymphocytes as well as an indirect qualitative effect on the function of several types of immune effector cells. The combination of T4-cell destruction and functional abnormalities contributes to the broad scope of immunologic aberrations and opportunistic diseases seen in HIV-infected individuals. In addition, HIV infection of monocyte/macrophages may play an important role as a reservoir or sanctuary of infection in the host and contribute to the characteristically long incubation period between HIV infection and disease. The activation of HIV from latent or chronically infected cells in vitro by mitogens, antigens, heterologous viruses, and cytokines represents a potential mechanism whereby HIV infection in individuals progresses from an asymptomatic carrier state to clinical AIDS. The release of virus from activated cells can lead to the spread of the virus to other target cells and result in both a qualitative or quantitative defect in immunocompetent cells and subsequent immunosuppression. It is also clear that HIV infection can result in the modulation of expression of certain cellular genes, thereby potentially compounding immunoregulatory abnormalities. Further knowledge of the complex relation between HIV and its target cells will be essential to our understanding of the myriad of potential pathogenic mechanisms of HIV infection and may lead to ways of interrupting the progression of HIV-induced disease.

Immunological abnormalities in human immunodeficiency virus (HIV)-infected asymptomatic homosexual men. HIV affects the immune system before CD4+ T helper cell depletion occurs

To investigate the effect of persistent HIV infection on the immune system, we studied leukocyte functions in 14 asymptomatic homosexual men (CDC group II/III) who were at least two years seropositive, but who still had normal numbers of circulating CD4+ T cells. Compared with age-matched heterosexual men and HIV-negative homosexual men, the CD4+ and CD8+ T cells from seropositive men showed decreased proliferation to anti-CD3 monoclonal antibody and decreased CD4+ T-helper activity on PWM-driven differentiation of normal donor B cells. Monocytes of HIV-infected homosexual men showed decreased accessory function on normal T cell proliferation induced by CD3 monoclonal antibody. The most striking defect in leukocyte functional activities was observed in the B cells of HIV-infected men. B cells of 13 out of 14 seropositive men failed to produce Ig in response to PWM in the presence of adequate allogeneic T-helper activity. These findings suggest that HIV induces severe immunological abnormalities in T cells, B cells, and antigen-presenting cells early in infection before CD4+ T cell numbers start to decline. Impaired immunological function in subclinically HIV-infected patients may have clinical implications for vaccination strategies, in particular the use of live vaccines in groups with a high prevalence of HIV seropositivity.

A review of peripheral tuberculous arthritis

There is a clear difference between TB infection and TB. Transition from the former to the latter involves host factors and perhaps environmental elements. Currently, more individuals with immunosuppressive situations caused by aging, debilitating diseases, immunosuppressive therapies, and HIV-III infection are predisposed to secondary forms of TB. Different patterns of clinical presentation, at variance with those previously described, could result from these changes in the host. PTBA is a good example. In the present review of 52 patients, we found that patient age is rising, as has been reported in other western countries. We also found that oligoarthritis and involvement of non-weight-bearing joints is becoming more common. From the diagnostic point of view, histological studies and cultures of synovial tissue remain the most reliable tests. Awareness of these factors, recognition of changing patterns, proper use of diagnostic procedures, and early treatment should improve the outcome of patients.

Alpha- and gamma-interferon (IFN alpha, IFN gamma) but not interleukin-1 (IL-1) modulate synthesis and secretion of beta 2-microglobulin by hepatocytes

Soluble serum beta 2-microglobulin has been thought to result from membrane shedding by activated T-lymphocytes. This hypothesis could explain the increase of beta 2-microglobulin serum levels during virally induced mononucleosis, but not elevated levels as observed in other virally induced and in malignant diseases. In this paper we demonstrate that beta 2-microglobulin is a true secretory protein, and that its synthesis in hepatocytes is modulated by IFNs but not by IL-1. While the 45,000 MW HLA antigen can be found only in cell lysates, beta 2-microglobulin is shown to be secreted also into the culture medium like other secretory proteins (e.g. albumin-factor B-complement C3). Furthermore, interferon alpha (IFN alpha) as well as interferon gamma (IFN gamma) directly stimulate, in a dose- and time-dependent manner, beta 2-microglobulin synthesis by human hepatoma cells (Mz-Hep-1 and PLC/PRF5) and murine hepatocyte primary cultures. The increase of beta 2-microglobulin production induced by interferons is demonstrated at both the protein and the RNA level, indicating that interferon acts at a pretranslational level. The interferon effect on beta 2-microglobulin synthesis is specific since synthesis of secretory proteins like complement C3 or albumin, and of a structural protein like actin, remains unchanged. In contrast to IFN, IL-1, the main mediator of acute phase response, does not change beta 2-M biosynthesis rate. These data indicate that (i) beta 2-microglobulin is a secretory protein, (ii) IFNs but not IL-1 can mediate increased beta 2-M serum levels, and (iii) the liver may be its primary source.

Ocular syphilis in patients with human immunodeficiency virus infection

We diagnosed ocular syphilis in three homosexual men infected with human immunodeficiency virus (HIV). Ocular inflammation included uveitis, optic neuritis, and retinitis. Dermatologic and central nervous system manifestations of secondary syphilis were also present. The history of homosexuality was difficult to obtain. Concomitant infection with HIV may alter the course of syphilis, obscure the diagnosis, and impair the response to therapy.

Human immunodeficiency virus (HIV)-induced cell fusion: quantification and its application for the simple and rapid screening of anti-HIV substances in vitro

A coculture system using Molt-4 and its HIV-producing cell, Molt-4/HIV(HTLV-IIIB) induced syncytia very efficiently. Among the cocultivations with various ratios of two types of cells, multinucleated giant cells were most clearly visible 20 hr after culture in a cell ratio of 5:5. The degree of cell fusion apparently correlated with the decrease in cell number during fusion reaction. The grade of the syncytia formation can be quantitatively expressed by the fusion index (FI). Using this system we evaluated various substances which are known to inhibit HIV replication and virus-induced cytopathogenicity in a cell-free viral infection. Glycyrrhizin sulfate, dextran sulfate, PSK, which is a protein-bound polysaccharide extracted from Basidiomycetes, and human plasma containing anti-HIV antibody gave about 15-fold reduction in FI when compared to that of control. At the same time no difference was seen between the FI given by two nucleoside analogs (3'-azido-2',3'-dideoxythymidine and 2',3'-didehydro-2',3'-dideoxythymidine) and that of control.

Cutaneous manifestations of the acquired immunodeficiency syndrome in children

The acquired immunodeficiency syndrome (AIDS) in children is now known to be a clinical entity separate and distinct from AIDS in adults. In this article we present a review of the recent literature describing the history, definitions, epidemiology, differential diagnosis, and immunologic and clinical features of pediatric AIDS. Special emphasis is placed on the cutaneous manifestations of human immunodeficiency virus infection in children, which, to date, have not been the subject of a comprehensive review.

Determination of acquired immunodeficiency syndrome (AIDS) after renal transplantation

Diagnosing the acquired immunodeficiency syndrome (AIDS) in transplant recipients can be difficult due to the patient's medication-induced immunosuppressed state. We report two renal allograft recipients who acquired HIV infection at the time of transplantation and later went on to develop multiple opportunistic infections. Careful documentation of HIV antibody status of the donor and recipient, when available, the nature of immunosuppressive therapy used, the type of infections and their timing after transplantation, as well as the patient's absolute T4 lymphocyte count, T cell ratio, and B cell humoral response to infection were used as factors to distinguish between infection related to immunosuppressive therapy and that seen in HIV-induced immunodeficiency. Reduction in immunosuppressive therapy because of the HIV-related immunodeficiency state did not result in allograft rejection. Both patients died of their multiple infections. The determination of AIDS in the transplant recipient has both therapeutic and prognostic significance. This diagnosis should be considered when transplant patients develop unusual infections in relationship to their posttransplant course.

Interferon-gamma: the major mediator of resistance against Toxoplasma gondii

Mice were injected with a monoclonal antibody to interferon-gamma to examine the importance of endogenous production of this lymphokine in resistance against infection with the sporozoan parasite Toxoplasma gondii. Mice with intraperitoneal infections of T. gondii that received no antibody survived and developed chronic T. gondii infection, whereas the infected mice that received the monoclonal antibody died of toxoplasmosis. The activation of macrophages, which kill T. gondii in vivo, was inhibited by administration of the monoclonal antibody, but the production of antibodies to T. gondii was not suppressed. The fact that an antibody to interferon-gamma can eliminate resistance to acute Toxoplasma infection in mice suggests that this lymphokine is an important mediator of host resistance to this parasite.

Prevalent myocarditis at necropsy in the acquired immunodeficiency syndrome

The prevalence of myocarditis was retrospectively evaluated in 71 consecutive necropsy patients who died from acquired immunodeficiency syndrome (AIDS) between 1982 and 1986. Myocarditis was found in 37 cases (52%). Biventricular dilation at necropsy was present in seven cases (10%) and was accompanied by myocarditis in each case; fatal congestive heart failure occurred in four of these seven cases. Although viral, protozoan, bacterial, fungal and mycobacterial opportunistic pathogens were present in myocardial sections of 7 of 37 myocarditis cases, the etiology of myocarditis in the majority of these patients with AIDS remained idiopathic. Thus, myocarditis is a frequent finding at necropsy in patients with AIDS and may contribute to the development of biventricular dilation.

The problem of human immunodeficiency virus (HIV) infection and transplantation

The problem of human immunodeficiency virus (HIV) infection and that of the acquired immunodeficiency syndrome (AIDS) are becoming increasingly important in clinical transplantation. The epidemiologic characteristics of this infection are important factors in determining the impact of this infection on transplant patients: in particular, the presence of a transmissible virus in the blood, tissues, and body fluids of even asymptomatic individuals for prolonged periods; the role of lymphocyte activation in accelerating the pace and effects of HIV infection, with the transplant patient having more reasons for lymphocyte activation than other patient categories; and the possible contributions of immunosuppressive therapy to the course of HIV infection. Already, at least 20 cases of primary HIV infection conveyed by infected blood or allografts at the time of transplant have been noted; a similar number of transplants have been carried out in asymptomatic carriers of the virus. The initial impression is that the course of HIV infection in these patients is accelerated, but information is incomplete and an international registry for the study of this problem has been established.

Entry of human immunodeficiency virus (HIV) into MT-2, human T cell leukemia virus carrier cell line

The ultrastructural features of early events in human immunodeficiency virus (HIV) infection of HTLV-I-carrying MT-2 lymphocytes were investigated by electron microscopy. Within 10 min after virus inoculation at 37 degrees C, the virus entered the cell in two ways; (1) the virus attached to the lymphocyte membrane and the viral core entered the cell after fusion of the viral envelope with the cell membrane, and (2) part of the cell membrane to which the virus was attached became invaginated, the virus became trapped in a phagosome and the viral core entered after the fusion of viral membrane with the vacuolar membrane. Thereafter, some cells were observed to form syncytia with multiple nuclei. When the proportion of anti-HIV antibody-reactive cells present exceeded 90%, virus production was strongly activated, and budding on the cell membrane was frequently observed.

A search for retrovirus infection in systemic lupus erythematosus and rheumatoid arthritis

Evidence for retroviral infection in general and human immunodeficiency virus (HIV) infection in particular was sought in freshly isolated peripheral blood T cells, B cells, and monocyte-macrophages from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) and also in T cell and B cell lines established from the same source. Similar cells isolated from rheumatoid synovial membrane were also examined. The strategy used for the detection of virus was cocultivation with susceptible cell lines looking for syncytia formation, reverse transcriptase production, and nucleic acid hybridisation with HIV cDNA probes. No evidence for infection was obtained.

The human immunodeficiency virus: infectivity and mechanisms of pathogenesis

Infection with the human immunodeficiency virus (HIV) results in a profound immunosuppression due predominantly to a selective depletion of helper/inducer T lymphocytes that express the receptor for the virus (the CD4 molecule). HIV also has tropism for the brain leading to neuropsychiatric abnormalities. Besides inducing cell death, HIV can interfere with T4 cell function by various mechanisms. The monocyte serves as a reservoir for HIV and is relatively refractory to its cytopathic effects. HIV can exist in a latent or chronic form which can be converted to a productive infection by a variety of inductive signals.

Peripheral blood mononuclear cell abnormalities and their relationship to clinical course in homosexual men with HIV infection

Quantitative abnormalities of leukocyte subpopulations have been shown to correlate with clinical status in human immunodeficiency virus (HIV) infection. We have performed peripheral blood leukocyte phenotyping in 23 HIV-seropositive homosexual men, and correlated the results with clinical follow-up information. Individuals with CD4+ greater than 400/mm3 (Group 1) had less severe abnormalities in other mononuclear cell subpopulations than patients with CD4+ less than 400/mm3 (Group 2). Group 1 had decreased CD4+CDw29+ (B-cell inducer) cells, compared to HIV-seronegative homosexual controls, with normal CD4+CD45R+ (suppressor-inducer) cells, suggesting that CD4+ subpopulations are reduced at different rates. Group 2 had decreased counts for both CD4+CDw29+ and CD4+CD45R+ cells. Both groups had increased cytotoxic T cells (CD8+CD11b-), with decreased B cells and CD4+/CD8+ ratios, compared to HIV-seronegative homosexual controls. The Group 2 patients with subsequent clinical deterioration had particularly low CD4+ cells, CD4+CD45R+ cells, CD2+Ta1+ cells, and CD4+/CD8+ ratios and high CD8+CD11b- cells, compared to those with clinically stable illness. Our findings suggest that specific leukocyte subpopulations are altered differentially at various stages of HIV infection. However, the study involved only quantitative measurements of specific T- and B-cell subsets with no attempt to measure in vitro function. It is of course possible that normal numbers of cells in these subpopulations might be functionally deficient.

The validity of immunological studies in human immunodeficiency virus infection: a three-year follow-up of 235 homo- or bisexual persons

During a three-year follow-up study of 235 risk-group people living in Finland, we found a slow increase in the proportion of HIV seropositives (from 9.8% to 14.0%) and a slow but continuous advance in symptoms typical of HIV infection among them. The first immunological changes after HIV seroconversion were an increase in Ts-cells and a decline in antigen-induced T-cell functions (proliferation, IL-2 production). A further decline in antigen-induced responses was seen before early clinical symptoms and signs of HIV infection developed. During later phases of HIV infection the decrease of Th-cells and the elevation of serum Beta-2 microglobulin correlated most strongly with the progression of HIV infection. The mitogen-induced lymphocyte functions of the HIV-infected correlated to Th-cell levels, while the antigen-induced proliferation and IL-2 production showed correlation neither to Th-cells nor to Ts-cells. The poor antigen-induced T-cell responses might be caused by abnormally functioning monocytes, known to be infected by HIV. Our results suggest that in HIV infection there is a continuous but slow disease progression, although individual variation may be great. The immunological parameter best predicting the prognosis of an infected person in the early phases of infection was the antigen-induced lymphocyte functions, and later the amount of Th-cells.

Immunologic dysregulation in a patient with familial hemophagocytic lymphohistiocytosis

A 6-year-old Jewish Iranian girl with familial hemophagocytic lymphohistiocytosis (FHLH) is described. The course of the disease fluctuated with partial initial response to antibiotics, steroids, and supportive treatment. Subsequent cytotoxic treatment, including VP-16, Velban (vinblastine sulfate), and methotrexate (MTX) controlled the disease for a few months but the child died with a clinical picture of meningocephalitis 1.5 years later. Benign-looking lymphohistiocytic infiltrates with varying degrees of hemophagocytosis were present in the bone marrow, pleural effusion, cerebrospinal fluid (CSF), liver, and brain. Clinical and laboratory evidence of immunologic dysregulation during the disease could be demonstrated. Frequent and intense viral and bacterial infectious diseases were encountered. The laboratory examination most consistently found was the absence of natural killer (NK) cell activity against K562 target cells. The impaired activity of NK cells persisted during all stages of the disease including remission, although NK cell numbers, determined morphologically and immunophenotypically (by Leu-11, Leu-7), were normal. Natural killer activity could not be restored by interferon. Moreover, the interferon system appeared to be intact. Impaired monokin interleukin 1 (IL-I) production by peripheral blood monocytes was found and could not be restored by indomethacin. Lymphopenia, a mild decrease in T4 numbers, and subsequently, decreased proliferative response to mitogens was noted. Elevated immunoglobulin levels were found during exacerbations and viral episodes, at times accompanied by the presence of auto-antibodies. The exaggerated fatal lymphohistiocytic response typical for FHLH could be attributed to a underlying genetic pathologic dysregulation of the various immunological response pathways.

Rheumatic manifestations of diseases associated with substance abuse

Rheumatic manifestations of substance abuse are uncommon but recognized complications. Repeated injections of drugs and adulterants represent repeated antigenic challenge. The population at greatest risk is that of young males, although females with eating disorders are more apt to develop myopathy, clubbing, or periostitis. Alcohol, the most common substance abused, is associated more often with myopathy. In IV drug abusers, hepatitis B viral infection, bacterial endocarditis, primary skeletal infections, and venous complications are most common in that order. However, the spectrum may evolve as the pattern of substance abuse changes. First, the frequency of cocaine dependence is rapidly approaching that of alcohol. Two regular cocaine users are reported as having Raynaud's phenomenon and abnormal serologies. Second, synthesis of lookalike drugs may produce new associations, such as parkinsonism after IV N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Third, the increased use of ipecac and purgatives in eating disorders is an important consideration in young women with otherwise unexplained myopathy or arthritis. Finally, patients with AIDS are presenting with autoimmune phenomena or a spectrum of unusual infections that change as the epidemic evolves. Increased recognition of these symptom complexes may lead to earlier, more accurate diagnoses and avoidance of unnecessary diagnostic evaluations and delays in treatment.

The effects of human immunodeficiency virus recombinant envelope glycoprotein on immune cell functions in vitro

The effect of human immunodeficiency virus (HIV) recombinant envelope glycoprotein 120 (rgp 120) on the functions of peripheral blood mononuclear cells (PBMC) in vitro was investigated. The results demonstrate that rgp 120 used at concentrations less than 1 microgram/ml has no significant effects on PBMC function in vitro. However, the addition of 1-20 micrograms/ml of rgp 120 significantly inhibits the tetanus toxoid-induced PBMC proliferative response in a dose-related manner as determined by [3H]thymidine incorporation. The data also show that rgp 120 (5 micrograms/ml) causes up to 70% reduction in the number of immunoglobulin G-secreting cells in pokeweed mitogen-stimulated PBMC cultures. Further, rgp 120 can selectively interact with the CD4a epitope of the CD4 helper cell membrane receptor. These results indicate that microgram per milliliter levels of rgp 120 can depress certain immune functions in vitro. The significance of these findings to the pathogenesis of immunodeficiency in HIV infection remains to be determined.

Theoretical implications of cellular immune reactions against helper lymphocytes infected by an immune system retrovirus

The breakdown of the immune system induced by the human immunodeficiency virus might be due to the active immune destruction of human immunodeficiency virus-infected helper T lymphocytes expressing viral antigens. By numerical simulation, we have studied possible consequences that a hypothetical immunodeficiency virus (IDV) may have on the cellular immune response by using a mathematical model. In this model, IDV infects CD4+ (helper) T cells and is actively synthesized by the immunologically activated helper T cells. Infected helper T cells synthesizing IDV express antigenic determinants specific for IDV and trigger a cellular immune response against themselves that is mediated by cytotoxic T cells and cytotoxic macrophages. The dynamic evolution of the model in the case of mixed-type infections with IDV and with another pathogen that evokes a cell-mediated immune response shows strong interactions between both simultaneous infections. The model might be of value to elucidate the dynamics leading to opportunistic infections. Furthermore, a pivotal role for immunological stimulation in the progressive exacerbation of the disease can be demonstrated.

Effect of recombinant human granulocyte-macrophage colony-stimulating factor on myelopoiesis in the acquired immunodeficiency syndrome

We administered recombinant (biosynthetic) human granulocyte-macrophage colony-stimulating factor (GM-CSF) to 16 patients with the acquired immunodeficiency syndrome (AIDS) and leukopenia (2225 +/- 614 cells per microliter [mean +/- SD]). Each patient first received a single intravenous dose; 48 hours later a 14-day continuous intravenous infusion of the agent was begun. The doses used were 1.3 X 10(3) (n = 4), 2.6 X 10(3) (n = 4), 5.2 X 10(3) (n = 4), 1.0 X 10(4) (n = 3), or 2.0 X 10(4) (n = 1) U per kilogram of body weight per day. Administration of recombinant GM-CSF resulted in dose-dependent increases in circulating leukocytes and in increases in circulating neutrophils, eosinophils, and monocytes. The peak leukocyte count ranged from 4575 +/- 2397 cells per microliter at the lowest dose, to 48,700 in the patient receiving the highest dose. Mild side effects--low-grade fever, myalgia, phlebitis, and flushing--were observed in some patients; there were no life-threatening toxic reactions. Our data demonstrate that recombinant human GM-CSF is well tolerated and biologically active in leukopenic patients with AIDS. Strategies to increase the number and function of circulating leukocytes may reduce the morbidity and mortality of infections in these and other patients with leukopenia.

Role of antibodies to murine leukemia virus p15E transmembrane protein in immunotherapy against AKR leukemia: a model for studies in human acquired immunodeficiency syndrome

Previous studies have demonstrated that the onset of AKR leukemia could be dramatically delayed and the overall incidence significantly reduced following treatment with high-titered heterologous antibodies directed against the gp71 major glycoprotein of the virus. However, to be maximally successful, the treatment had to be initiated during the postnatal period of the AKR mouse, encompassing a narrow window representing approximately the first 3 days of life. In the present study we sought to extend this barrier by including antibodies directed against a second envelope component of the virion, the transmembrane protein, p15E. We demonstrate that although neither antibodies to gp71 nor antibodies to p15E could influence the course of leukemia development when applied individually later in life, a combination of the two antibodies was effective even if given as late as 5 months after birth. The significance of these studies is discussed in relation to human retrovirus-associated diseases.

Correlation of enzyme-linked immunosorbent assays for serum human immunodeficiency virus antigen and antibodies to recombinant viral proteins with subsequent clinical outcomes in a cohort of asymptomatic homosexual men

A cohort of asymptomatic homosexual men at a Boston community health center was screened for the presence of human immunodeficiency virus (HIV) serum antigen and antibodies to recombinant proteins containing portions of the envelope and the gag (core) gene products. Of 196 asymptomatic men screened, 149 were antigen-negative/antibody-negative, 41 were antigen-negative/antibody-positive, and six were antigen-positive/antibody-positive. All three men in whom the acquired immune deficiency syndrome (AIDS) developed over the next year were antigen-positive at enrollment. Although a larger portion of the men who were antigen-positive and did not demonstrate progression to AIDS after one year had thrush, zoster, or generalized lymphadenopathy, the associations were not statistically significant. Whereas all of the seropositive men had antibody to viral envelope antigens, about a quarter did not have detectable antibodies to recombinant core antigens. However, all of these men had detectable antibody to core antigens by Western blot. Titers to recombinant core and envelope antigens tended to be lower in the men with AIDS. HIV-infected persons who are more likely to have enhanced immuno-compromise may be identified by these newer tests, but further longitudinal studies will be necessary to fully understand their prognostic value.

Alteration in the natural history of neurosyphilis by concurrent infection with the human immunodeficiency virus

Within the past 18 months, we have seen four cases of neurosyphilis at our institution (two of meningovascular syphilis, one of acute syphilitic meningitis, and one of asymptomatic neurosyphilis) in young homosexual men with serologic evidence of exposure to human immunodeficiency virus (HIV). Two of the four patients had neurosyphilis despite previous adequate therapy for early syphilis with benzathine penicillin. Meningovascular syphilis developed in one patient within four months after a primary infection, in a manner consistent with an accelerated course of syphilitic infection. These findings suggest the possibility that HIV infection may alter the natural course of syphilis because of the profound defects in cell-mediated immunity it causes. The possible potentiating effects of HIV on Treponema pallidum infection suggest the need for lumbar puncture in the evaluation of HIV-seropositive patients with syphilis, as well as modifications of the currently recommended treatment regimens for primary, secondary, and latent syphilis and neurosyphilis in this patient population. Neurosyphilis should probably be added to the growing list of infectious complications of the acquired immunodeficiency syndrome (AIDS) and may be the first such complication to appear.

Selective expansion of a CD3+CD4-CD8- subpopulation in clinical groups associated with human immunodeficiency virus infection

T lymphocytes (CD3+) without expression of CD4/CD8 surface antigens have recently been described in the thymus and peripheral lymphoid organs. We have conducted a retrospective analysis of the literature, seeking quantitative variations in this T-cell subset in normal heterosexual controls, and in risk, pre-AIDS, and AIDS groups, by means of the subtraction [CD3-(CD4+CD8]) and the ratio 100 X [CD3-(CD4+CD8])/CD3. Dramatic T lymphocytopaenia in AIDS patients and the progressive decay of CD4+ lymphocytes and increase of CD8+ lymphocytes throughout the clinical spectrum of HIV infection have been confirmed. Furthermore, we hereby demonstrate the selective expansion of CD3+CD4-CD8- lymphocytes, directly related to the clinical state in different clinical groups of infected people when compared with controls (P less than 0.05). The inverse relationship between the CD3+CD4-CD8- cell subset and other mature T-cell subsets, mainly CD4+ (r = -0.49; P less than 0.01), suggests the existence of mutual regulatory interactions. These in vivo results, which are in agreement with those obtained in long-term infected cultures, cannot be explained by direct cytopathic effects of the virus on the very few infected cells. Thus, the implication of the expansion of these functional precursors on the prognosis for infected people, and the paradoxes of the immunodeficiency, such as lymphoproliferation and autoimmune features, are discussed.

Interleukin 1 inhibitor masks high interleukin 1 production in acquired immunodeficiency syndrome (AIDS)

Monocyte functions, including interleukin 1 (IL-1) production, have been shown previously to be impaired in acquired immunodeficiency syndrome (AIDS). We have fractionated culture supernatants from unstimulated peripheral blood mononuclear cells (PBMCs) to determine whether the low IL-1 activity in AIDS was due to the presence of IL-1 inhibitors. The results demonstrate that PBMCs from patients with AIDS produce increased amounts of IL-1 activity compared with those of controls together with marked increases (10- to 20-fold) in the amounts of 50,000-100,000 and 6000-9000 molecular weight (MW) factors which inhibit IL-1 activity. These inhibitors mask IL-1 activity measured in the standard thymocyte proliferation assay for IL-1. The 6000-9000 MW IL-1 inhibitor shows the greatest increase in all AIDS patients (n = 5) compared with that of controls (n = 7). This inhibitor may block the IL-1 dependent maturation of T lymphocytes in AIDS and thereby contribute to the immunodeficiency.

Hypersensitivity reactions to drugs in acquired immunodeficiency syndrome

We describe a patient with AIDS in whom recurrent drug eruption and fever following administration of various unrelated agents developed. Previous drug exposure was uneventful. A possible mechanism for this phenomenon is described.

Therapy of acquired immune deficiency syndrome with recombinant interleukin-2

Recombinant human interleukin-2 (rIL-2) was administered to 87 patients with the acquired immune deficiency syndrome (AIDS) to test the hypothesis that this lymphokine would correct the underlying qualitative and quantitative deficiency in cellular immunity. Patients were divided into two groups by the presence or absence of Kaposi's sarcoma and subjects within each of these groups received intravenous rIL-2 three times weekly for eight weeks. Subjects received one of several doses which ranged from 1,000 to 2,000,000 units per square meter body surface area. Toxicity at high doses consisted of flu-like symptoms and hypotension at highest doses. Partial objective tumor regression was observed in three patients with Kaposi's sarcoma. Seventeen patients had progression of disease (new opportunistic infection or increase in Kaposi's sarcoma) during therapy. No improvement in immunologic status was observed. This study does not suggest a role for single-agent rIL-2 therapy of established AIDS but its use in less symptomatic persons or in conjunction with antiretroviral agents such as azidothymidine should be investigated.

Cytotoxic factors secreted by cells infected by human immunodeficiency virus type I

Conditioned media from human immunodeficiency virus type I (HIV-1) infected cells were tested for cytotoxic cell-derived factors. The assay used a murine fibroblast cell line which is sensitive to the effects of tumor necrosis factors, but nonpermissive for HIV-1 replication. Cytotoxic activity was detected in cultures of peripheral blood mononuclear cells infected with HIV-1. However, no differences in activity were found in conditioned media from infected lymphoid or monocytoid cell lines compared to their uninfected counterparts. These data suggest that cytotoxic activities of this type are not mediators of cell killing resulting from HIV-1 infection. Thus, this cytotoxic activity is a direct or indirect result of virus replication or cytopathicity. One should consider a role for this cytotoxic factor, secreted by HIV-1 infected mononuclear cells, in various aspects of infection in vivo, such as AIDS encephalopathy or the systemic manifestations accompanying ARC.

Management of infectious and immunological complications of acquired immunodeficiency syndrome (AIDS). Current and future prospects

AIDS is caused by a newly recognised virus (human immunodeficiency virus; HIV) which induces a profound defect in cellular immune function associated with increased susceptibility to opportunistic infections and certain malignancies. The clinical presentation of HIV ranges from asymptomatic infection to severe immunodeficiency manifesting as severe life-threatening infectious diseases or malignancies. While major research efforts are being directed toward development of vaccine and discovery of effective antiretroviral drugs, clinicians are faced with AIDS patients with multiple and complicated medical problems including opportunistic infections and certain malignancies. Currently, efforts are directed toward early diagnosis, treatment, and prevention of recurrence of these opportunistic infections. The current approaches are reviewed in this article. Major recent developments in AIDS research include the isolation of the HIV on culture and the availability of the antibody test. Aside from vaccine and antiretroviral drugs, other measures that may be of benefit in the treatment of AIDS patients are immunological enhancement and reconstitution. Several studies are underway to evaluate antiviral agents in the treatment of HIV infection. Those undergoing clinical trial include suramin, ribavirin, antimoniotungstate, phosphonoformate and azidothymidine. Immune enhancers that have been used include alpha- and gamma-interferon and interleukin-2. HLA-matched lymphocyte transfusions and bone marrow transplantations have been used alone and in combination to replace the AIDS patient's defective immune system.

Mycobacterium avium-M. intracellulare isolates from patients with or without acquired immunodeficiency syndrome

Susceptibility testing and serotyping were performed on 57 isolates of Mycobacterium avium-M. intracellulare from patients with acquired immunodeficiency syndrome (AIDS) and 75 isolates from patients without AIDS. Susceptibility patterns and serotypes of AIDS isolates were significantly different from those of non-AIDS isolates. These results may partially explain the poor therapeutic response of M. avium-M. intracellulare infections in AIDS patients.