The Definition of HIV-specific Neuropathology

Evaluation of a neuropathological series of 160 HIV infected patients, almost all in the terminal AIDS stage of the infection, allowed recognition of novel syndromes which can be regarded as HIV specific neuropathology because: 1) they are not observed in non HIV tissues; 2) HIV is, in our hands consistently by immunocytochemistry, demonstrable in large amounts within these lesions; 3) other pathogens are not detectable within these lesions; and 4) these lesions may occur in isolated fashion within CNS tissues (40% of HIV-specific neuropathology in this series), without any other CNS pathology. HIV specific neuropathology was found in 34% in this series and comprised two prototypes within a spectrum of frequently overlapping changes: multifocal microgranulomatous lesions of HIV encephalitis, and diffuse white matter damage of HIV leukoencephalopathy. In almost all cases, multinucleated giant cells signal the local presence of HIV in routine stains. In contrast to HIV-specific neuropathology, various unspecific nervous tissue syndromes do not consistently exhibit the local presence of HIV and thus are designated HIV associated or possibly HIV induced lesions: lymphocytic meningitis, vacuolar myelopathy, multifocal vacuolar leukoencephalopathy, and diffuse poliodystrophy. Although these unspecific syndromes may also contribute to clinical manifestations, their pathogenetic relation with HIV remains to be established.     

Immune complexes in the acquired immunodeficiency syndrome (AIDS): Relationship to disease manifestation,risk group,and immunologic defect

Immune complex assays (and other immunologic tests) were performed on sera from 162 patients with the acquired immunodeficiency syndrome (AIDS) and 275 AIDS-related subjects. Immune complexes were detected in 89% of AIDS patients and 93% of homosexual men with lymphadenopathy. Immune complex levels in AIDS patients were not associated with a particular risk group or with types of opportunistic infection or malignancy; however, they correlated with other laboratory features of the immune defect (depression in T helper cells and T helper/suppressor-cell ratio, and IgG levels). Immune complexes were also detected in a lesser proportion of risk-group controls (homosexual men, hemophiliacs, Haitians). In risk-group controls, immune complex levels were associated with certain features reflecting sexual practice, blood product exposure, or infection, but these features did not account for the higher levels found in AIDS patients. In appropriate situations, immune complex assays may be of value as screening tests or, possibly, as prognostic indicators for AIDS or AIDS-related syndromes.     

Neutralizing antibodies as a prognostic indicator in the progression of acquired immune deficiency syndrome (AIDS)-related disorders: A double-blind study

A double-blind longitudinal study for the presence of human immunodeficiency virus type 1 (HIV-1) neutralizing antibodies (NAb) in the sera of 36 patients with acquired immune deficiency syndrome (AIDS), 149 prodromal homosexual subjects, and 33 heterosexual subjects has been carried out. All AIDS patients and 68% of prodromal homosexual subjects (101/149) were found to be HIV-1 antibody positive by Western blot assay. All heterosexual subjects were HIV-1 antibody negative. Neutralizing antibody(s) was determined by testing the protective activity of sera against HIV-1 infection of human T-cell line H9. Study subjects were divided into NAb(+) (antibody titer, >1:40) and NAb(–) (antibody titer, <1:40) groups. During the 24-month observation period 2 of 80 (3%) HIV-1(+) NAb(+) individuals progressed to AIDS and died, as compared to 5 of 21 (24%) of HIV-1(+) NAb(–) subjects who progressed to AIDS. Similarly, among the NAb(+) AIDS patients 8 of 23 (35%) died, while 10 of 13 (77%) of the NAb(–) patients died during the course of the study. In addition, the absence or reduction of HIV-1 p17 and p24 antibodies directed against HIV-1 antigens as well as the low titer or absence of NAb appears to be closely related to the clinical progression of the disease. These studies suggest that a decrease in the virus neutralization capacity of the sera and a decrease or complete loss of HIV-1 p17 and p24 antibodies may be useful as prognostic indicators for the progression of disease in HIV-1-seropositive patients.     

Submicroscopic Profile of Isospora belli Enteritis in a Patient with Acquired Immune Deficiency Syndrome(doubt)

Small bowel mucosal fragments from a human immunodeficiency virus-positive female patient with chronic diarrhea were investigated by transmission electron microscopy, and Isospora belli enteritis was documented. The submicroscopic profile was characterized by a moderate abnormality of mucosal architecture with reduction in height of villi and hypertrophy of crypts. Stages of both asexual (trophozoite, schizont, and merozoite) and sexual (macrogametocyte) phases of the life cycle of the parasite were identified in the epithelium, always enclosed within a parasitophorous vacuole. Moreover, the presence of occasional extracellular merozoites in the intestinal lumen and in the lamina propria near or within lymphatic vessels was documented. These findings expand the current knowledge of this parasite regarding its capacity to survive in an extracellular environment and document a possible mechanism by which extraintestinal infection can take place.     

Submicroscopic Profile of Isospora belli Enteritis in a Patient with Acquired Immune Deficiency Syndrome(doubt)

Small bowel mucosal fragments from a human immunodeficiency virus-positive female patient with chronic diarrhea were investigated by transmission electron microscopy, and Isospora belli enteritis was documented. The submicroscopic profile was characterized by a moderate abnormality of mucosal architecture with reduction in height of villi and hypertrophy of crypts. Stages of both asexual (trophozoite, schizont, and merozoite) and sexual (macrogametocyte) phases of the life cycle of the parasite were identified in the epithelium, always enclosed within a parasitophorous vacuole. Moreover, the presence of occasional extracellular merozoites in the intestinal lumen and in the lamina propria near or within lymphatic vessels was documented. These findings expand the current knowledge of this parasite regarding its capacity to survive in an extracellular environment and document a possible mechanism by which extraintestinal infection can take place.     

Acquired immune deficiency syndrome (AIDS) and autoimmunity—Mutually exclusive entities?

Loss of normal immune homeostasis occurs in acquired immune deficiency syndrome (AIDS). We evaluated patients at the University of Cincinnati and New York University Medical Centers for serologic evidence of autoimmune changes. Specifically, tests for antinuclear and organ-specific antibodies by immunofluorescence, antisperm and anti-seminal plasma antibodies, rheumatoid factor by latex and sensitized sheep cell agglutination techniques, anti-polyadenosine (poly A), and single-stranded DNA antibodies were performed in human immunodeficiency virus (HIV) antibody-positive sera. A parallel study of mitogen responsiveness was performed and showed inhibition of response by AIDS and AIDS-related complex (ARC) sera. In spite of evidence of polyclonal B-cell activation, hyperglobulinemia, and the presence of antibodies to many infectious agents, as well as the known cellular immune abnormalities, the patients tested had a striking absence of these autoantibodies. The only major difference noted from normal controls, was a low but significant level of antibody binding to poly A. The autoimmune connective tissue diseases were not observed in this group of patients.     

Ultrastructural Findings in the Acquired Immunodeficiency Syndrome (AIDS)

Ultrastructural studies have made significant contributions in evaluating the pathology and pathogenesis of AIDS. Three distinct types of abnormal cytomembranous inclusions in tissue specimens or peripheral blood mononuclear cells from AIDS patients are described—vesicular rosettes (VR), tubuloreticular inclusions (TRI), and cylindrical confronting lamellae ICCL).     

Malignant Lymphomas in Japanese AIDS Patients

Seven non-Hodgkin's malignant lymphomas (MLs) were found in 25 Japanese AIDS (acquired immune deficiency syndrome) patients who died at two hospitals in Tokyo. All of these MLs originated from extranodal organs including the brain (three cases), skin (two cases) liver and adrenal gland. B cell markers were demonstrated in all of them. Epstein-Barr virus (EBV) capsid antigen (EBVCA) was demonstrated in 5/7, nuclear antigen (EBNA) in 2/2, the W fragment of EBV DNA by in situ hybridization in 5/7 and the same fragment by PCR in 6/7, indicating high association of these MLs with EBV. The adult T cell leukemia/lymphoma (ATL), endemic in south-west Japan and known to have a high association with HTLV-I, was not found in this series. The incidence of ML among the present AIDS cases is higher than in any other autopsy reports from western countries, although statistical analysis did not show this to be significant in comparison to some of these reports at a level of p<0.05. In spite of apparent higher incidence, the histopathologic and immunophenotypic characteristics of AIDS-associated MLs in Japan are in accordance with those in western countries. Acta Pathol Jpn 41: 744-750, 1991.     

用流式细胞仪检测HIV感染者和AIDS患者的T细胞亚群

目的用流式细胞仪（ｆｌｏｗｃｙｔｏｍｅｔｅｒ,ＦＣＭ）检测周围血中ＣＤ４＋、ＣＤ８＋淋巴细胞,结合临床情况对ＨＩＶ感染者和ＡＩＤＳ患者的免疫状况进行评价。方法将抗凝全血进行白细胞分类计数,用双色荧光标记的单克隆抗体染色,经溶血和固定后,用ＦＣＭ计数,从而得出ＣＤ４＋、ＣＤ８＋淋巴细胞数。结果ＨＩＶ感染者和ＡＩＤＳ患者的ＣＤ４＋淋巴细胞数都比正常人低,特别是ＡＩＤＳ患者,他们的ＣＤ４＋淋巴细胞数都低于２００个／ｍｍ３,临床表现也很差。结论ＦＣＭ检测结果与临床评价高度一致,而且ＦＣＭ比一般人工计数法更准确、方便、迅速,同时也证明ＦＣＭ是监测ＨＩＶ感染者和ＡＩＤＳ患者的免疫状况的最佳方法。     

Immune impairments and antibodies to HTL VIII/LAV in asymptomatic male homosexuals in Israel: Relevance to the risk of acquired immune deficiency syndrome (AIDS)

We have studied 288 Israeli asymptomatic male homosexuals (MHS) to determine the prevalence of antibodies to HTLVI and HTLVIII and their correlation with impairments of the immune system and serum interferon (IFN). Seropositivity for HTLVI, HTLVIII, or both was found in 1.4, 8.3, and 0%, respectively. Significant decreases in the total peripheral T cells, T_H cells, and T_H/T_S ratio as well as elevated IFN serum levels were found in the MHS group in comparison with normal controls. Although no difference in the prevalence of either immune derangements or elevated serum IFN was observed between HTLVIII/LAV-seropositive and HTLVIII/LAV-seronegative MHS, the decreases in total T cells, T_H cells, and T_H/T_S ratios were significantly greater in the seropositive MHS. These results indicate that (a) immune impairments and IFN system activation occur commonly in homosexuals, precede their exposure to HTLVIII/LAV, and probably reflect this group's increased risk for AIDS and (b) HTLVIII/LAV infection of MHS aggravates further their preexisting immune impairments.     

An Autopsy Case of Purulent Mycobacterial Meningitis in AIDS

The patient was a 46 year old male hemophiliac who died of acute mycobacterial meningitis associated with AIDS (acquired immune deficiency syndrome). Autopsy revealed severe basal meningitis which was characterized by an infiltration of numerous polymorphonuclear leukocytes. Severe mural inflammation of the subarachnoid arteries was noted, and innumerable acid-fast bacilli were demonstrated. Epithelioid cell granulomas were not found in the meningeal lesion. The lungs, liver, spleen, and bone marrow contained many epithelioid cell granulomas with caseous necrosis. Massive proliferation of swollen histiocytes could not be identified in any organ. The absence of epithelioid cell granulomas in the meningeal lesion indicate a severe impairment of cell-mediated immunity in the patient; this anergic type of lesion is one of the characteristics of tuberculosis occurring in association with terminal AIDS. Acta Pathol Jpn 41: 895-899, 1991.     

Defective T-cell differentiation in acquired immune deficiency syndrome (AIDS)

A decline in T-cell lymphocyte number is the central characteristic of acquired immune deficiency syndrome (AIDS). The reason for the loss of these cells is not well understood. We investigated the hypothesis that defects in T-cell differentiation contributed to T-cell loss using anin vitro colony assay that measures T-cell precursor (CFU-T) frequency. The results indicate a substantial generalized decrease in CFU-T in people with AIDS (P<0.01), most of whom have Kaposi's sarcoma, and an occasionally severe decrease in CFU-T in people with ARC. Some of the cells from low colony formers suppressed colony formation by control cells. In addition, plasma from people with AIDS was less supportive of colony growth than control plasma. Decreased Ia expression on adherent mononuclear cells did not correlate with colony formation. A defect in T-cell repopulation can help explain the loss of T cells associated with AIDS.     

Methionine-enkephalin as immunomodulator therapy in human immunodeficiency virus infections: Clinical and immunological effects

Enkephalins have been shown to enhance T cell-mediated immune responses and natural killer-cell activityin vitro. We have studied the effects of infusions of methionine-enkephalin on immune functions and clinical courses in seven patients with various stages of infection with human immunodeficiency virus (HIV). All patients were clinically stable at the time of entry into the study. Each received 10 µg/kg of methionine-enkephalin in an intravenous infusion three times weekly for up to 12 weeks. Evaluation of cellular immunity (T-cell subsets,in vitro interleukin-2 production and interleukin-2 receptor expression, T-cell responses to mitogens and antigens, and delayed-hypersensitivity skin tests) as well as clinical and toxicity monitoring was performed prior to treatment, at 2-week intervals during treatment, and after the cessation of treatment. Increases in interleukin-2 receptor expression were seen on lymphocytes collected on one occasion from each of two patients 30 min postinfusion. Studies done 24 hr after infusions revealed increases in interleukin-2 production in one patient, but when pre- and posttreatment values were compared there were no significant changes in numbers of circulating T cells of any phenotype or in T-cell responses to mitogens or antigens. None of the patients with Kaposi's sarcoma had regression of tumor; one patient dropped out of the study at week 5 because of deteriorating clinical status and progression of tumor. There were no adverse reactions or evidence of toxicity. We conclude that methionine-enkephalin appears to enhance temporarily selected immune responses in patients with HIV infection, however, in the schedule used in this study it was not clinically efficacious.     

Acquired immunodeficiency syndrome (AIDS) — Related renal disease

Summary More than 87,000 patients with acquired immunodeficiency syndrome (AIDS) were reported to the Centers for Disease Control in the United States, of whom more than half died through January 1989. When the AIDS epidemic is considered worldwide, these numbers should be doubled at least [27]. Whereas electrolyte disorders and acute renal complications were recognized early on in the AIDS epidemic, it was not until 1984 that a nephropathy was described in patients with human immunodeficiency virus-Type 1 (HIV-1) (formerly called LAV/HTLV-III) infection [18, 30, 36]. This nephropathy was characterized, clinically, by heavy proteinuria or the nephrotic syndrome and a rapid progression to end-stage chronic renal failure and, pathologically, by an aggressive form of focal segmental glomerulosclerosis. The existence of an AIDS-related nephropathy was not readily accepted because of its uneven geographic distribution amongst areas severely affected by the AIDS epidemic [24, 48]. This brief review summarizes the clinical and pathologic features of AIDS-related nephropathy.     

The significance of antilymphocyte antibodies in patients with acquired immune deficiency syndrome (AIDS) and their sexual partners

Antilymphocyte antibodies have been demonstrated in autoimmune diseases, acute viral infections, and acquired immune deficiency syndrome (AIDS) by using either the conventional microlymphocytotoxicity or the double fluorescence technique. In the present study, we used both methods to detect the antilymphocyte antibodies and to characterize further their immunologic significance in patients with AIDS and their sexual partners. The results using the conventional microlymphocytotoxicity method demonstrated that 8 of 10 patients with AIDS and 6 of 10 partners had significant levels of antilymphocyte antibodies which were reactive with B and T cells at cold and warm temperatures. A significant loss in antibody activity following absorption with B, T, and Daudi cells andStaphylococcus aureus, but not platelets or red cells, indicated that these antibodies are not directed to HLA class I antigens but, rather, to antigens that are common to both groups of lymphocytes. There is a close association between antilymphocyte antibodies and lymphopenia in patients but not in partners. Antibodies against lymphocyte subclasses [helper (T4) and suppressor (T8)] were detected by the double fluorescence staining technique, which employs C6-deficient serum as a nonlytic source of complement, and demonstrated the binding of antibodies to target cells, in contrast to lysing of the target cells as in the microlymphocytotoxicity method. The results of this assay showed that antibodies were directed to both populations, and there was no correlation or association between the absolute numbers of peripheral T4 and T8 cells and the percentage of antibody binding. Taken together, there appear to be at least two kinds of antilymphocyte antibodies: lymphocytotoxic antibodies detected by the conventional microlymphocytotoxicity assay and noncytotoxic antibodies detected by the double fluorescence staining technique. The former may be responsible in part for the lymphopenia. The latter may alter lymphocyte function. The patients and partners who had antilymphocyte antibodies also had anti-HTLV-III antibodies, although there was not any close correlation between titers. These findings support the possibility that both types of antibodies occur as part of a generalized immune response, possibly stimulated by the same viral agent.     

Class II (DR) antigen expression on CD8+ lymphocyte subsets in acquired immune deficiency syndrome (AIDS)

In a selected group of human immunodeficiency virus (HIV)-infected patients we confirm the expansion of a CD8⁺ T-lymphocyte subset, i.e., the CD8⁺/Leu7⁺ cells, which account for 30% of the lymphocytes, compared to 3% in the control donors. In addition, a CD8⁺ T-lymphocyte subset that coexpresses class II (DR) antigens, i.e., CD8⁺/DR⁺ cells, is also increased from 1.5% in controls to 27% in the HIV-infected patients. Using three-color immunofluorescence and flow cytometry we can demonstrate that the CD8⁺/Leu7⁺ and the CD8⁺/class II⁺ cells are not distinct but overlapping subsets. In the HIV-infected patients 42% of the CD8⁺/Leu7⁺ cells were strongly positive for class II and these CD8⁺/Leu7⁺/class II⁺ cells accounted for 13% of all lymphocytes. These findings indicate that the expanded CD8⁺/Leu7⁺ cells are activated and hence might be actively involved in immune defense in acquired immune deficiency syndrome (AIDS).     

Serum and effector-cell antibody-dependent cellular cytotoxicity (ADCC) activity remains high during human immunodeficiency virus (HIV) disease progression

The activity of both serum and effector cell antibody-dependent cellular cytotoxicity (ADCC) against human immunodeficiency virus (HIV-1, HIV) was assessed in HIV-infected individuals. The goal was to relate ADCC levels with the stage or progression of HIV disease. Serial serum samples, usually collected at 6-month intervals, from individuals at defined stages of HIV disease (sero-conversion, the HIV-seropositive period before AIDS, and around the time of clinical AIDS diagnosis) were tested. HIV-coated CEM tumor cells were used as targets. Effector-cell ADCC activity was evaluated using fresh peripheral blood mononuclear cells (PBMC) from HIV-infected individuals at different stages of HIV disease. Samples were obtained from male homosexual participants in the Multicenter AIDS Cohort Study (MACS). In seroconverters, ADCC-inducing HIV-specific antibodies were detected at the time that the ELISA antibody test was first positive. Within several months, serum ADCC activity stabilized in each individual. In 29 HIV-seroprevalent individuals (HIV seropositive on their first visit), serum ADCC activity remained constant regardless of whether the individual's HIV disease was stable (high stable CD4;n=9) or rapidly deteriorating (sharply declining CD4,n=10; AIDS progressors,n=10). With respect to effector-cell activity, PBMC from HIV-infected individuals with or without AIDS were capable of mediating ADCC with heterologous and usually with autologous sera. Although the level of NK cytotoxic activity and the level of antibody-armed effector cell activity have been reported to decline as disease progresses, our results support previous observations that ADCC effector-cell activity against antibody-coated targets does not decline in HIV infection. These results indicate that both serum and effector cells with ADCC activity are present in HIV-infected individuals shortly after seroconversion and are maintained throughout HIV disease. Although levels of serum and effector-cell ADCC activity do not predict whether an individual will develop AIDS, CD4 cells which express HIV antigens (either produced endogenously or adsorbed onto the surface) could serve as targets for anti-HIV-mediated ADCCin vivo. ADCC could, thereby, contribute to CD4 T-cell depletion in infected individuals. However, since serum and effector-cell ADCC levels do not seem to relate to disease stage or progression, the protective or pathogenic role that ADCC plays in HIV-disease remains unresolved.     

Cytomegalovirus Vasculitis Accompanied by an Exuberant Fibroblastic Reaction in the Intestine of an AIDS Patient

A case of cytomegalovirus (CMV) vasculitis in the intestine of a patient with acquired immune deficiency syndrome (AIDS) is reported. The distal jejunum and ileum had multiple well-demarcated mucosal ulcers and microscopic examination revealed an unusual, exuberant fibroblastic proliferation in the ulcer base. Amidst these fibroblasts, there were several small blood vessels of which the endothelial cells contained cytomegalic inclusion bodies. The lesion showed a Kaposi's sarcoma-like appearance, but spindle cells were negative in immunostaining for factor VIII related antigen or Ulex europaeus agglutinin 1. Although the CMV infection was observed in almost all organs, the exuberant fibroblastic proliferation seen in the intestine was not found in other organs. This lesion might represent a peculiar reaction of the immunologically compromised host to the CMV in the intestinal blood vessels. Acta Pathol Jpn 41: 900 904, 1991.     

Abnormality of Leu 2+7+ cells in acquired immune deficiency syndrome (AIDS), AIDS-related complex,and asymptomatic homosexuals

Peripheral blood mononuclear cells from patients with acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC), asymptomatic homosexuals, and healthy heterosexuals were analyzed for the proportions and numbers of Leu 7⁺ cells and double-labeled Leu 2⁺7⁺ cells and for the natural killer functions. A significant increase in the proportions and numbers of Leu 7⁺ cells was observed in patients with AIDS and ARC and in asymptomatic homosexuals compared to healthy heterosexual men. The proportions of Leu 2⁺7⁺ cells were significantly increased in AIDS, ARC, and asymptomatic homosexuals, whereas the numbers were increased in asymptomatic homosexuals and ARC but not in AIDS compared to heterosexual controls. A significant increase in the number of Leu 2⁺7⁺ cells was observed in AIDS with Kaposi's sarcoma but not in AIDS with opportunistic infections. The natural killer function was significantly depressed in patients with AIDS and ARC and in asymptomatic homosexuals. These data suggest that the quantitative abnormalities of Leu 2⁺7⁺ cells appear early during the evolution of immunologic changes in HTLV III/LAV infection.