Isolation of HTLV-III from cerebrospinal fluid and neural tissues of patients with neurologic syndromes related to the acquired immunodeficiency syndrome

Mutational analysis of the human immunodeficiency virus vpr open reading frame

Mutations were introduced by recombinant DNA techniques into the vpr open reading frame of an infectious molecular clone of human immunodeficiency virus type 1. The effect of these changes on the replicative and cytopathologic properties of the virus recovered from transfected cells was studied in several human CD4+ lymphocyte cell lines. In all cases, mutant viruses were infectious and cytopathic. However, when a low-input dose was used, mutants grew significantly more slowly than the wild-type virus. The growth kinetics of vpr mutants were distinct from those of vif and vpu mutants.

[Cerebrospinal fluid abnormalities in 170 cases of AIDS]

Cerebrospinal fluid (CSF) was analysed in 170 AIDS patients. All of them showed HIV positive serological tests. All of them showed neurologic syndromes related to AIDS. The time period of the investigation was July 1984-April 1989. In 8 cases (4.7%) CSF composition was normal. Lymphoma cells were observed in three cases. Aseptic meningities occurred in 34 cases (20.1%). Aetiological diagnosis of associated infection was established in 88 cases: cryptococcosis in 28 (35.9%); toxoplasmosis in 20 (25.6%); syphilis in 10; candidiasis in 3; Chagas disease in 2; tuberculosis in 1; nocardiosis in 1; schistosomiasis in 1. Antibodies for other virus were detected in 7. Bacteria were isolated in 5 cases. Anti-HIV antibodies were tested in CSF samples of 55 cases: they were found in 48 (87.3%). Two or more associated infections were observed in 15 cases. Changes of CSF composition in AIDS are discussed taking into account changes reported.

New approaches to the delivery of drugs to the brain

The Human Immunodeficiency Virus (HIV) is the causative agent of AIDS and this has been found to be neurotropic. For this reason the development of an effective strategy for the delivery of antiviral drugs across the blood-brain barrier is of paramount importance in the treatment of HIV infection. There are insulin receptors on the capillary endothelial cells making up the blood-brain barrier (BBB) and it is proposed that these may play a role, along with exogenously administered insulin, in enhancing the transport of drug molecules across the BBB. Evidence is presented showing that insulin may be used as a pharmacologic adjunct in the therapy of HIV infection by allowing for higher concentrations of antiviral drugs to be obtained within the CNS using lower total doses of drug. This would enhance the drug's therapeutic effectiveness while simultaneously obviating potential dose-related side-effects.

Indole amine deficiency in blood and cerebrospinal fluid from patients with human immunodeficiency virus infection

Twenty-four patients with human immunodeficiency virus (HIV) infection were investigated for possible changes in certain indole amine constituents in blood and cerebrospinal fluid (CSF). Albumin in serum was determined and used as a rough nutritional marker. Six of the 24 patients had acquired immunodeficiency syndrome AIDS, four had other clinical symptoms of HIV infection, and 14 had no apparent symptoms. The HIV-seropositive patients had significantly decreased tryptophan values; their blood concentrations were 28% lower and their CSF concentrations 30% lower than corresponding values in 14 healthy controls. The blood concentrations of 5-hydroxytryptamine (5-HT) were 50% lower, and the platelet content of 5-HT was 36% lower in HIV-infected individuals than in the control group. The most pronounced changes were invariably seen in the six cases with AIDS and in patients with a low number of CD4+ cells. No significant difference between controls and HIV-seropositive patients was detected in the mean CSF concentrations of 5-hydroxyindoleacetic acid (5-HIAA), although these levels were markedly reduced in four of the HIV patients. Neither was any significant difference seen between patients and controls in the serum concentrations of albumin.

Generation of hybrid human immunodeficiency virus by homologous recombination

Human immunodeficiency virus (HIV) type 1, isolated from diverse sources, exhibits genomic diversity. The mechanisms by which the genomic diversity takes place in individuals exposed to multiple virus isolates is yet to be elucidated. Genetic variation, in general, might result from mutagenic events such as point mutations, rearrangements (insertions and deletions), and recombination. In an attempt to evaluate the process of genetic diversity, we designed experiments to analyze recombination between HIV DNAs by using DNA transfection in cell cultures. Here we report the successful recombination between truncated HIV proviral DNAs with an overlap homology of 53 base pairs that leads to the formation of viable hybrid virus. Recombination was also seen between exogenous DNA introduced into cells and homologous HIV sequences resident in the cells. These results indicate that recombination among various HIV isolates may play a significant role in the generation of genetic diversity of HIV. Further, the method used here enables the construction of hybrid HIV genomes to identify the viral determinants responsible for tropism, replication, and cytopathic effects.

Progressive neurological dysfunction during latent HIV infection

OBJECTIVE--To determine whether the delayed conduction through the spinal cord and peripheral nerves seen in patients with AIDS is related to infection with HIV or to the presence of an immunodeficient state. DESIGN--Two year prospective follow up study of electrophysiological measurements in subjects positive for HIV antibody but without AIDS. SETTING--HIV screening clinic and clinical departments in a university hospital in Copenhagen, Denmark. SUBJECTS--Twelve homosexual men positive for HIV antibody who had not developed AIDS. RESULTS--Eight latencies were measured: from the ankle to T12, the wrist to C7, T12 to the cerebral cortex, C7 to the cerebral cortex, the ankle to the gluteal crease (tibial nerve), the gluteal crease to T12, the wrist to Erb's point (median nerve), and Erb's point to C7. Spinal latencies increased in all subjects at C7 by a mean of 4.2% (SE 0.9%) and in all except one at T12 by a mean of 5.5% (1.0%). The conduction time from the gluteal crease to T12 was increased by a mean of 32.0% (5.0%) whereas that in the median and tibial nerves by only 5.6% (1.0%) and 2.2% (2.2%) respectively. CONCLUSIONS--A mild and slowly progressive peripheral neuropathy of the axonal type and a more severe progressive myelopathy or myeloradiculopathy occur concomitantly with early HIV infection, possibly as the result of a direct neurotropic action of HIV.

Ocular manifestations of acquired immune deficiency syndrome

The ocular complications of acquired immune deficiency syndrome (AIDS) include: (1) a noninfectious microangiopathy, most often seen in the retina, consisting of cotton-wool spots with or without intraretinal hemorrhages and other microvascular abnormalities; (2) opportunistic ocular infections, primarily cytomegalovirus (CMV) retinitis; (3) conjunctival, eyelid, or orbital involvement by those neoplasms seen in patients with AIDS (i.e., Kaposi's sarcoma and lymphoma); and (4) neuro-ophthalmic lesions. In a series of 200 AIDS patients evaluated clinically, AIDS retinopathy was present in 66.5%. Sixty-four percent had cotton-wool spots, and 12% had intraretinal hemorrhages. Cytomegalovirus retinitis was diagnosed in 28% of AIDS patients. Neuro-ophthalmic lesions were found in 8% of all AIDS patients and were present in 33% of those patients with cryptococcal meningitis. Acquired immune deficiency syndrome retinopathy was present in 40% of 35 patients with the AIDS-related complex (ARC) and in 1.3% of 232 patients with asymptomatic human immunodeficiency virus (HIV) infection, evaluated photographically. These results suggest that the prevalence of AIDS retinopathy increases with increasing severity of HIV infection, and that CMV retinitis presents a significant vision-threatening problem in AIDS patients.

Potential human health risks associated with animal retroviruses: some hypotheses

Several studies have demonstrated the existence of morphological, biological, genetic and antigenic correlations between human and animal retroviruses. Furthermore, some agents of bovine and feline origin can also be considered useful comparative models for the pathogenetic study of human diseases such as leukaemia, acquired immunodeficiency syndrome (AIDS) and multiple sclerosis (MS). In spite of the existence of data suggesting a possible role of some animal retroviruses (e.g. the bovine leukosis virus, BLV) in the etiology and epidemiology of human leukaemia and MS, the true zoonotic potential of such agents remains unknown, but their genetic and antigenic linkages with some human lentiviruses (such as the human immunodeficiency virus-1, HIV 1) can make them hypothetically responsible for a certain number of false-positive serological reactions in man, especially in those subjects who are professionally exposed to animal lentiviruses. In the present paper particular reference is made to this last hypothesis which, if confirmed, would suggest a larger scale-utilization of more specific diagnostic tests for HIV infection in man, such as the immunoblotting techniques.

Ultrastructural behavior of human immunodeficiency virus (HIV) in multinucleated giant cells in the brain of a Japanese hemophiliac presenting AIDS encephalopathy

Human immunodeficiency virus (HIV) was detected ultrastructurally and immunohistochemically in the brain of a Japanese hemophiliac presenting AIDS encephalopathy. The encephalopathy was characterized by the multifocal occurrence of multinucleated giant cells mainly in the subcortical areas. The giant cells were identified immunohistochemically to be macrophages. HIV particles were observed in and out of the giant cells, and most of the particles ingested in the cells were membrane-bound. Some virus particles were found in pinocytic vesicles or phagocytic vacuoles, whereas the others were degradated in the lysosomes of the cells. Budding of HIV particles from the cell surface was also observed, indicating replication of the virus in vivo. These findings suggest ingestion, digestion, and replication of HIV by brain macrophages in AIDS.

Pharmacokinetics and saturable renal tubular secretion of zidovudine in rats

The purpose of this study was to assess the effects of dose on the pharmacokinetics of zidovudine (3'-azido-3'-deoxythymidine; AZT) in rats. Zidovudine (AZT) was administered intravenously at doses of 10, 50, 100, and 250 mg/kg. Plasma and urine AZT concentrations were determined by HPLC. Plasma AZT concentrations declined rapidly with a terminal half-life ranging from 0.76 h at a dose of 10 mg/kg to 1.58 h at 250 mg/kg. Total clearance (CLT) was similar at the doses of 10 and 50 mg/kg, with values of 2.80 and 2.73 L/h/kg, respectively. However, there was a trend toward nonlinearity at the dose of 100 mg/kg (CLT = 2.13 L/h/kg) and a significant decrease in CLT (1.22 L/h/kg) at the dose of 250 mg/kg. Nonrenal clearance remained unaffected by dose with a mean value of 0.98 L/h/kg. Renal clearance (CLR) was similar at the doses of 10 and 50 mg/kg, with values of 1.89 and 1.37 L/h/kg, respectively. However, significant decreases in CLR were observed at the doses of 100 (CLR = 1.30 L/h/kg) and 250 mg/kg (CLR = 0.57 L/h/kg). The maximum transport capacity (Tmax) and the Michaelis-Menten constant (Km) for renal tubular secretion obtained after simultaneously fitting plasma concentration-time profiles at the four doses to a renal clearance model were 215.5 +/- 82.1 mg/h and 119.3 +/- 80.5 mg/L, respectively, thereby yielding an unbound secretory intrinsic clearance (CLus,int) of 1.81 L/h. The high Tmax and Km values account for the high CLR of AZT and explain the linearity of CLR over a wide range of AZT plasma concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Subclinical neurological and neuropsychological effect of infection with HIV

Thirty one homosexual men with antibody to human immunodeficiency virus (HIV) but without major neurological complaints were assessed in a cross sectional study of neurological and neuropsychological function. Eleven patients had AIDS, 10 had persistent generalised lymphadenopathy (PGL), and 10 had HIV infection without PGL (called "well"). Thirteen age matched homosexual men without antibody to HIV acted as controls. Significant abnormalities were found in six on clinical neurological examination, in eight on nerve conduction studies, in six on electroencephalography, in six on neuropsychological assessment, and in eight on computed tomography of the head. Eighteen patients (nine with AIDS, four with PGL, and five "well") performed abnormally in at least one section of the assessment. The study highlights the incidence of nervous system dysfunction in HIV infection even in people who do not have AIDS. Prospective evaluation using electrophysiological and imaging techniques is necessary to assess the natural history of such manifestations and the effect of antiviral treatment.

AIDS-dementia-complex: pathology, pathogenesis and future directions

Acquired immunodeficiency syndrome (AIDS), first described in 1981, is produced by infection with a retrovirus of the lentivirus family, now called human immunodeficiency virus (HIV). While, initially, the disease was almost exclusively seen in homosexual men, it has become apparent that numerous other categories of people are at risk, i.e., drug addicts who share dirty needles, hemophiliacs and haitians. In addition, epidemiological data from the industrialized nations clearly indicate that heterosexual contact is becoming an important source of viral transmission, as it has been known to occur in several african nations for many years. Initially, studies on patients with AIDS mainly focused on the immunosuppressive effects of the virus and on the various opportunistic infections and neoplastic complications that followed. Not much attention was given to a possible direct HIV infection of the nervous system. Consequently, patients who presented with neurological findings were simply considered to harbor in the CNS the same complications that occurred in other organs. While this was true in many cases, it has become also apparent that important changes in the central and peripheral nervous systems are due to direct viral involvement of these tissues. The first important step in the understanding of nervous system involvement in AIDS was the demonstration, in 1985, of HIV in the CSF and cerebral tissues of patients with neurological symptoms (47). Further studies have shown that, while opportunistic infections and neoplastic complications certainly contribute to the neurological morbidity of AIDS, the most important neuropathological changes, particularly in the brain, are due to direct HIV infection. The aim of this paper is to review the pathology of HIV-induced encephalitis and to discuss pathogenetic hypotheses regarding mechanisms of HIV-mediated tissue injury and the clinical manifestations that follow, particularly the syndrome now known as AIDS-Dementia-Complex (ADC). First, however, it may be appropriate to quickly review some basic notions on the biology of the virus.

Spinal cord and peripheral nerve pathology in AIDS: the roles of cytomegalovirus and human immunodeficiency virus

We examined spinal cords, nerve roots, or peripheral nerves of 27 patients who died with acquired immunodeficiency syndrome (AIDS) for the presence of cytomegalovirus (CMV) and human immunodeficiency virus (HIV) by immunoperoxidase techniques in paraffin-embedded tissue. Vacuolar myelopathy was seen in 8 of 26 spinal cords (31%) and microglial nodules were seen in 13 (50%). All of the patients with lateral column vacuolar myelopathy showed severe brain pathology. HIV antigens had been detected in the brains of 15 (55%) of the 27 patients but were detected in only 3 (11%) of 26 spinal cords and were not localized to regions of vacuolar myelopathy. This suggests that the vacuolar myelopathy may be due to a remote or indirect effect of HIV or other infectious agent. CMV antigens were detected in none of the patients who showed vacuolar myelopathy but were detected in 2 of the 13 with microglial nodules. Focal nerve root or peripheral nerve inflammation was seen in 7 patients; 4 had CMV antigens and none had HIV antigens. CMV appears to be an important cause of inflammatory peripheral neuropathy in AIDS patients.

The spectrum of changes on 20 nerve biopsies in patients with HIV infection

Nerve and muscle biopsies were performed on 20 patients with HIV infection and peripheral neuropathy. Nine patients had distal symmetrical peripheral neuropathy (DSPN) (six ARC and three AIDS), six had inflammatory demyelinating polyneuropathy (IDP) (three ARC, one AIDS, and two otherwise asymptomatic patients), one had mononeuropathy multiplex (MM) (AIDS), 1 had mononeuropathy (ARC), one had meningoradiculitis (AIDS), and two had areflexia-associated lymphocytic meningitides (ARC), DSPN exhibited axonal degeneration in four of nine cases and was associated with segmental demyelination in five of nine cases. IDP exhibited segmental demyelination associated with axonal degeneration in four of six cases. Demyelination was more frequent in asymptomatic patients (2 of 2 cases) and in ARC (7 of 12 cases), whereas axonal degeneration was predominant in AIDS (6 of 6 cases). Mononuclear cell infiltration was seen in 1 of 2 asymptomatic patients and in 11 of 12 ARC patients but was exceptionally found in AIDS (1 of 6 cases). Involvement of the walls of small vessels, mostly venules ("subacute microvasculitis"), was found in 1 of 2 asymptomatic patients, in 8 of 12 ARC patients, and never in AIDS. The polyclonal mononuclear cell population was composed mainly of Leu 2 (T8) positive cells in seven cases of ARC. No virions were seen in electron microscopy. HIV was isolated in two cases from the CSF or the nerve biopsy.

Human immunodeficiency virus type 1 in spinal cords of acquired immunodeficiency syndrome patients with myelopathy: expression and replication in macrophages

Spinal cord disease is common in patients infected with human immunodeficiency virus type 1 (HIV-1), and a characteristic vacuolar myelopathy is present at autopsy in approximately one-fourth of acquired immunodeficiency syndrome patients. Pathologic examination of the spinal cord shows vacuolation of white matter and infiltration by macrophages, a process distinct from HIV-1 encephalopathy. To determine the presence and localization of HIV-1 RNA in the spinal cords of acquired immunodeficiency syndrome patients with vacuolar myelopathy, we used the technique of combined in situ hybridization and immunohistochemical staining on the same slide. Spinal cord tissue sections were stained with markers for macrophages, endothelial cells, oligodendroglia, astrocytes, and myelin and then hybridized in situ with HIV-1-specific RNA probes. Combined in situ hybridization and immunohistochemical staining on three spinal cords showed HIV-1 expression in mononuclear and multinucleated macrophages localized mainly to areas of myelopathy in spinal cord white matter. Immunohistochemical staining and electron microscopy showed myelin within macrophages and electron microscopy revealed HIV-1 budding from macrophages. These data suggest a role for HIV-1-infected macrophages locally in the pathogenesis of vacuolar myelopathy and add to the body of evidence that these cells play a role systemically in the development of HIV-1-related disease.

Factitious AIDS in a psychiatric inpatient

This article reports the case of a 28 year-old female presenting to a psychiatric inpatient unit with depression and a history of acquired immune deficiency syndrome (AIDS). Although medical assessment was negative for AIDS, psychiatric evaluation and psychological testing were consistent with a presentation of factitious disorder. This case illustrates the need to be on the alert for individuals admitted to psychiatric units who report they have AIDS or its related conditions.

Evaluation of intracerebral lesions in patients with acquired immunodeficiency syndrome. Neuropathological findings and experimental data

In this paper we present the results of post-mortem examinations of the central nervous system in 61 male patients who died with Acquired Immunodeficiency Syndrome (AIDS); it includes 23 patients with reported neurological abnormalities at the time of presentation. The analysis revealed central nervous system (CNS) neoplasms (lymphoma, Kaposi's sarcoma) and a variety of inflammatory lesions (bacterial, fungal, protozoal and viral) in 32 cases. A total of 11 patients without opportunistic infections showed significant brain abnormalities characterized by microglial nodules and/or multinucleated giant cells, changes which are probably related to infection by human immunodeficiency virus (HIV). In addition, we describes results from a series of experiments designed to define the target cell population of HIV in the brain. The expression of CD4 complex--putative receptor for HIV--was investigated using short-term cultured brain cells taken from embryonic brain anlage and from different regions of fetal brain; glioma cells were also used. Cells derived from normal embryonic and fetal brain, as well as glioma cells, were examined with respect to their susceptibility to HIV. CD4 antigen expression could be demonstrated only on glioma cells of the permanent glioma line 85HG-59 comprised of cells with properties characteristic of astrocytes. Nevertheless, normal embryonic and fetal brain cells as well as glioma cells could be infected by HIV as documented by immunocytochemical methods and southern blot analysis. HIV infected brain cells showed reduced growth rate and altered growth pattern. This study emphasizes the diversity of HIV conditioned CNS impairments, suggesting that genomic variability of HIV may result in varying cell type preference of the virus. The experimental data indicate that CD4 expression in brain cells is probably not 'conditio sine qua non' for HIV susceptibility. The alterations of HIV-infected brain cells demonstrated provide further evidence for a direct involvement of HIV in the pathogenesis of AIDS-related neurological syndromes.

HIV-1 core proteins expressed from recombinant vaccinia viruses

The sequences encoding the core proteins p55, p25, and p18 of the human immunodeficiency virus (HIV-1) have been inserted into the vaccinia virus genome. Infection of cultured cells with the live recombinant viruses led to the expression of proteins that were recognized by sera from HIV-seropositive individuals. Immunization of mice with the recombinant virus expressing the HIV p25 protein and the p55 precursor yielded high levels of antibodies directed against the corresponding HIV antigens. The data obtained are discussed in terms of the possible use of these live recombinant viruses in the development of a strategy toward an AIDS vaccine.

Pathology of brain and eye in the acquired immune deficiency syndrome (AIDS). A comparison of lesions in a consecutive autopsy material

During the years 1984-1987, a consecutive Danish autopsy material of 43 AIDS cases was analysed in order to investigate a possible coincidence of pathological changes in brain and eye. In the brain, nodular gliosis/encephalitis was most frequent, followed by cytomegalovirus infection, which occurred twice as frequently as toxoplasmic infection and four times as frequently as fungal infection. In the eye, cytomegalovirus infection was most frequent and the only opportunistic infection, followed by retinal gliosis and cytoid body lesion. Malignant lymphoma was present in the brain in three patients, and in the choroid in two of these. In 11 patients, no changes of the brain were found. In eight of these the eye was also without pathological findings, while three had minor changes. In 22 patients the eye was normal, but in only eight of these was the brain without changes. Eight had nodular gliosis, and four a specific infection, while multifocal leucoencephalopathy and unspecified abscess each occurred in one patient. Comparison of the three opportunistic infections--CMV, toxoplasmosis and mycosis--in the three-year period showed an overall decreasing frequency, attributed to better medical care. It is concluded that concomitance of identical pathological lesions in brain and eye is less frequent than was expected.

[Acute polyradiculoneuritis and acquired immunodeficiency virus]

A 50-year-old man with positive test for human immunodeficiency virus (HIV) by enzyme-linked-immunoassy and Western-blot, without clinical manifestations of acquired immunodeficiency syndrome (AIDS), developed acute polyradiculoneuritis and was treated by plasmapheresis with improvement. We believe that chemical homologies of antigenic determinants between HIV and P2 protein of peripheral nervous system and myelin basic protein may induce crossed-reaction, thus developing acute polyradiculoneuritis and central nervous system involvement, respectively. The nervous system involvement hy HIV also occur in the HI-viremy, seric conversion alone, and AIDS with or without oportunistic infections.

Relationship between the occurrence of virus in plasma and cerebrospinal fluid of HIV-1 infected individuals

Attempts to isolate human immunodeficiency virus type 1 (HIV-1) were carried out on cerebrospinal fluid (CSF) and blood plasma samples from 111 HIV-1 infected subjects in various stages of infection. HIV-1 was recovered at a low rate from CSF of persons with normal immunological parameters but frequently from patients with abnormal values, in all stages of immune system involvement. Isolation from plasma was positive in the majority of the patients, in all stages of infection, with a frequency that was related to the degree of immunodeficiency. HIV-1 could be recovered from the CSF of most patients (74%) with viremia when 85 paired specimens of 58 patients were analyzed. By contrast, HIV-1 was isolated from CSF, but not from plasma, in one case only. HIV-1 p24 antigen measured by an enzyme-linked immunosorbent assay (ELISA) was detectable in only four CSF samples compared with 15 serum samples in paired specimens. These findings indicate that most patients with HIV-1 infection have circulating cell-free infectious virus in the blood and simultaneously demonstrable HIV-1 in the CSF. Replication of HIV-1 exclusively in the central nervous system (CNS) appears to be a rare event.

Ultra low field brain MRI in HIV transfusion infected patients

In order to assess possible structural changes and possible alterations in T1 relaxation times in the brains in a group of female patients (67-74 years) infected with HIV following transfusion ultra low field (ULF) magnetic resonance imaging (MRI) was performed. The width of the ventricles, the width of the subarachnoid spaces, the degree of white matter lesions and T1 relaxation times in the frontal white matter, the basal ganglia and thalamus were studied. No temporal structural changes nor alterations in T1 relaxation times were found in the brains in this group of transfusion infected patients, who were followed regularly over a period of 12 months compared both to themselves and to age matched controls.