Epidemic hemorrhagic fever with renal syndrome in Yugoslavia, 1986

An epidemic of hemorrhagic fever with renal syndrome (HFRS) occurred in Yugoslavia May-November 1986; all Republics and Provinces were involved. Serum samples were received from 260 of 276 persons with symptoms clinically compatible with a diagnosis of HFRS. Presumptive infection with a hantavirus was determined serologically for 161 of these. Many patients with serious clinical pictures, including severe renal insufficiency and shock, were hospitalized; 11 died. Indirect fluorescent antibody tests with antigens of 4 hantaviruses (Hantaan, Fojnica, Puumala, and the Vranica strain of Puumala virus) showed that greater than 1 serotype was circulating during this epidemic. Hantavirus antigens were detected in the lungs of 86 of 302 (28.5%) wild-caught small mammals.

The nucleus basalis of Meynert in parkinsonism-dementia of Guam: a morphometric study

The nucleus basalis of Meynert (nbM) was studied morphometrically in three Guamanians with parkinsonism-dementia (PD) and in two Guamanian and two non-Guamanian controls. Paraffin-embedded blocks of the nbM were serially sectioned (20 microns thick) at increments of 200 microns so that a total of 24 sections (eight each from the anterior, intermediate and posterior sectors of the nbM) were studied. The mean cell density was determined for each sector and the diameter of 50 neurons, randomly chosen in the region of apparent maximal density, was calculated. A decrease of the mean cell density, due to the loss of neurons with diameters larger than 20 microns, was found in the PD cases compared to the controls. Two PD patients exhibited striking neuronal loss (65-95%) with predominant involvement of the intermediate and posterior sectors, while the third case showed only minimal neuronal loss in these sectors (15-40%). In both Guamanian and non-Guamanian controls large neurons (diameters greater than or equal to 20 microns) exceeded small neurons while the reverse was true in all sectors of the nbM for the PD cases. These data, while confirming a previous study reporting neuronal loss in the nbM of PD patients, underline the importance of detailed morphometric analysis of the different sectors of the nbM to recognize those patients in whom lesions are not uniformly distributed.

A prospective study of asthma during pregnancy and the puerperium

Thirty-one asthmatic women recruited in an ante-natal clinic were followed during pregnancy and for six weeks of the puerperium. Subjectively 22 (69%) women considered their asthma to have improved, two were worse and in seven (22%) there was no change. Analysis of peak flow rate, symptoms score and bronchodilator use showed that in ten pregnancies there was improvement in the third trimester and that in 11 there was deterioration in the puerperium. The results suggest that in patients with mild or moderate asthma an improvement is likely to occur during pregnancy, particularly in the last trimester, but that in over one-third there may be a post-natal deterioration. Review of the literature suggests that severe asthmatics are at greater risk of deterioration, particularly late in pregnancy.

Comparison of a human T-cell lymphotropic virus type I strain from cerebrospinal fluid of a Jamaican patient with tropical spastic paraparesis with a prototype human T-cell lymphotropic virus type I

The isolation and characterization of a human T-cell lymphotropic retrovirus related to human T-cell lymphotropic virus type I (HTLV-I) from cerebrospinal fluid of a Jamaican patient with tropical spastic paraparesis is described. The virus isolate is a typical type C retrovirus as seen by electron microscopy and is related to prototype HTLV-I isolated from patients with adult T-cell leukemia but is not identical to this prototype HTLV-I as seen by restriction enzyme mapping.

Neuronal degeneration and neurofilament accumulation in the trigeminal ganglia in Creutzfeldt-Jakob disease

We report the pathological and immunohistochemical changes in the first-order neurons in the trigeminal ganglia in Creutzfeldt-Jakob disease (CJD). Degenerative changes consisted of cytoplasmic vacuolation and fenestration, abundant satellite cells, neurofilament accumulation in neurons, and axonal dystrophy with spheroid formation and torpedolike structures arising from the neuronal cytoplasm. Dystrophic axons, axonal spheroids, and some ganglion cells were labeled with monoclonal antibodies to a phosphorylated epitope of neurofilaments (200 kDa). Polyclonal antibodies to purified scrapie-associated fibril/prion protein (molecular weight 27-30 kDa) extracted from scrapie-infected hamster brains, as well as polyclonal and monoclonal antibodies to a synthetic 15-amino acid polypeptide of the 27- to 30-kDa protein, demonstrated variable immunoreactivity with degenerating neurons in the CJD cases, but not in the controls. Furthermore, some of the satellite cells and dystrophic axons were stained by the antibodies to the synthetic peptide. These data indicate that the first-order neurons of the trigeminal ganglia may form a route by which the CJD agent may travel from the brain to the periphery or vice versa. As in other chronic neurodegenerative diseases, disturbances of neuroaxonal transport seem to occur in CJD.

Leakey virus: a new hantavirus isolated from Mus musculus in the United States

A hantavirus, designated Leakey virus, was isolated from a Mus musculus captured in Real County, Texas, U.S.A. in August 1986. Virus-specific fluorescence was first detected 13 days after inoculation of Vero-E6 cells with spleen tissue from the seropositive M. musculus. Ultrastructurally, the new isolate resembled other hantaviruses. Leakey virus induced a fatal meningoencephalitis in infant Fischer rats, with viral antigen detectable in brain, lung, liver, kidney and spleen. Serum dilution, plaque reduction neutralization tests indicated that Leakey virus was antigenically distinct from Hantaan, Seoul, Puumala and Prospect Hill viruses, and therefore constitutes a new serotype.

Serological evidence of hantavirus infection in laboratory rats and personnel

Laboratory-acquired haemorrhagic fever with renal syndrome (HFRS) has been reported in many countries. A serological survey of laboratory white rats and of laboratory personnel for antibodies to hantaviruses was conducted in Singapore. Forty-four per cent (143/329) of rats were seropositive by the indirect immunofluorescent antibody test but none had hantaviral antigens in lung tissues. Two of 74 laboratory personnel were seropositive but neither had a history of clinical illness. The high seropositivity rate among laboratory rats led to their replacement with Hantaan virus-free strains. To eliminate the hazard of laboratory-acquired HFRS, regular serological screening of laboratory rats and replacement of infected animals with seronegative stocks should be implemented. High risk techniques with laboratory rats, which are likely to generate aerosols, should be performed in biological safety cabinets. Serological surveillance of laboratory personnel and reporting of suspected HFRS cases are useful in the early detection of hantavirus infection.

Intracerebral inoculation of experimental animals with brain tissue from patients with schizophrenia. Failure to observe consistent or specific behavioral and neuropathological effects

To test the possibility that some cases of schizophrenia result from infection with a transmissible slow viral agent, 57 experimental animals (six chimpanzees, 12 Old World monkeys, 17 New World monkeys, and 22 guinea pigs) were inoculated intracerebrally with brain tissue from ten patients and followed up for six years. Behavioral comparisons with control animals revealed no consistent behavioral differences. Histological, immunohistochemical, and morphometric examination of brains of animals that died revealed no specific neuropathological abnormalities. These findings do not support a role for a virus-induced slow infection in the pathogenesis of schizophrenia but must be weighed against methodological limitations in animal susceptibility, disease communicability, and assay sensitivity.

Human immunodeficiency virus type 1 neutralization epitope with conserved architecture elicits early type-specific antibodies in experimentally infected chimpanzees

Chimpanzees are susceptible to infection by divergent strains of human immunodeficiency virus type 1 (HIV-1), none of which cause clinical or immunological abnormalities. Chimpanzees were inoculated with one of four strains of HIV-1: human T-lymphotropic virus (HTLV) type IIIB, lymphadenopathy virus (LAV) type 1, HTLV type IIIRF, or an isolate from the brain of a patient with acquired immunodeficiency syndrome. Within 6 months after inoculation with the closely related strains HTLV-IIIB or LAV-1, six chimpanzees developed serum antibodies to the C-terminal half (amino acids 288-467) of the HTLV-IIIB external envelope glycoprotein gp120. Sera from five of those chimpanzees had HTLV-IIIB cell-fusion-inhibiting antibody titers greater than or equal to 20 at that time, indicating that they neutralized the infecting strain of HIV-1 in vitro. No antibodies to the carboxyl terminus of HTLV-IIIB gp120 were observed in sera of chimpanzees inoculated with HTLV-IIIRF or with the brain-tissue strain, and those sera did not neutralize HTLV-IIIB. A rabbit immunized with the C-terminal portion of gp120 acquired neutralizing antibodies that bound to four domains of the HTLV-IIIB external envelope as analyzed by reactivity to 536 overlapping nonapeptides of gp120. One of these domains in the variable region V3, with the amino acid sequence IRIQRGPGRAFVTIG (amino acids 307-321), bound to all chimpanzee sera that neutralized HTLV-IIIB but not to the serum of the HTLV-IIIRF-inoculated chimpanzee that did not neutralize HTLV-IIIB. The HTLV-IIIRF sequence at the same location, ITKGPGRVIYA, was recognized by the serum of the HTLV-IIIRF-inoculated chimpanzee but not by any sera of the HTLV-IIIB-inoculated or LAV-1-inoculated chimpanzees. The HTLV-IIIB residues RIQR and AFV and the HTLV-IIIRF residues lysine and VIYA, flanking a highly conserved beta-turn (GPGR), appear to be critical for antibody binding and subsequent type-specific virus neutralization. This neutralization epitope, putatively consisting of a loop between two cysteine residues (amino acids 296 and 331) connected by a disulfide bond, is immunodominant in HIV-1-infected chimpanzees and induces antibodies restricted to the homologous viral strain.

Temporal development of cross-neutralization between HTLV-III B and HTLV-III RF in experimentally infected chimpanzees

Sera from chimpanzees inoculated respectively with HTLV-III B, LAV, HTLV-III RF and brain tissue from an AIDS patient were analysed for neutralizing activity by two methods: a cell fusion inhibition test (CFI) using HTLV-III B infected cells as inoculum and CD4+ cells as target and a replication inhibition test (RIT) using cell-free HTLV-III B as well as HTLV-III RF as inoculum and also CD4+ cells as target. All chimpanzees seroconverted for HTLV-III B antibodies within 2 months after inoculation and the ten sera included in the study recognized the HTLV-III B core proteins p17 and p24 and the transmembrane protein gp41 by immunoblotting. The HTLV-III B external envelope gp120 was recognized by eight sera with antibodies active in the CFI (CFI-Ab) or in the RIT (VN-Ab) using HTLV-III B as inoculum, while neither of two sera without such reactivity did. HTLV-III B CFI-Ab and HTLV-III B VN-Ab concurred in nine of ten serum samples. LAV and HTLV-III B infection induced HTLV-III B CFI-Ab and HTLV-III B VN-Ab within 9 months after inoculation in all four chimpanzees tested. However, only the serum of one of the four animals also neutralized HTLV-III RF. HTLV-III RF inoculation evoked only HTLV-III RF VN-Ab within nine months. Between 11 and 18 months neutralizing activity to both HTLV-III B and HTLV-III RF was found in all four sera of chimpanzees inoculated with HTLV-III B, LAV or HTLV-III RF.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental hantavirus infection in nonhuman primates

Mild, transient proteinuria and azotemia were produced in three cynomolgus monkeys (Macaca fascicularis) and a chimpanzee (Pan troglodytes) following intravenous inoculation with Prospect Hill virus, a hantavirus isolated from meadow voles in the United States. This is the first demonstration of an acute nephropathy in nonhuman primates with the viruses causing hemorrhagic fever with renal syndrome.

Spastic paraparesis and HTLV-I infection in Peru

Three of 6 patients with spastic paraparesis in Lima, Peru, were found to have antibodies to human T-lymphotropic virus type I (HTLV-I). Blood and cerebrospinal fluid antibodies were confirmed by Western blot analysis. Multilobulated lymphocytes in blood and cerebrospinal fluid of the index case stained with monoclonal antibodies for T-helper cells and for T10, an activation marker. Blood mononuclear cells from patients with HTLV-I-associated myelopathy showed spontaneous proliferation in culture, evidence of interleukin-2 receptors, and decreased natural killer cell activity.

Histochemical and X-ray microanalytical localization of aluminum in amyotrophic lateral sclerosis and parkinsonism-dementia of Guam

Histochemical staining for aluminum, using Solochrome azurine or Morin, provided a rapid, simple and reliable means of identifying areas and structures of the brain of interest for closer scrutiny by X-ray microanalysis in patients with amyotrophic lateral sclerosis and parkinsonism-dementia of Guam. Neuronal perikarya, dendritic processes, and the walls of some cerebral vessels were aluminum positive by Solochrome azurine staining. In some cases, the deposition of aluminum was rather diffuse, particularly in the white matter. Fluorescent localization of aluminum using Morin was equally sensitive and specific, but provided less morphological detail than Solochrome azurine. Confirmation of histochemical detection of aluminum was achieved by examining adjacent tissue sections using wavelength-dispersive spectrometry coupled to a computer-controlled electron beam X-ray microprobe. Although the minimum detectable limits for aluminum by these histochemical procedures are unknown, the lower detection limit of our X-ray microanalytical technique is 10-100 ppm dry weight. Solochrome and Morin staining, as verified by X-ray microanalysis, afford a useful and reliable means of surveying multiple anatomical regions for aluminum deposition in naturally occurring and experimentally induced neurodegenerative disorders.

HTLV-I-like viral particles in spinal cord cells in Jamaican tropical spastic paraparesis

Viral-like particles morphologically identical to human T-lymphotropic virus type I or II, but distinct from human T-lymphotropic virus type III, have been seen by electron microscopy in spinal cord tissue from a Jamaican tropical spastic paraparesis patient who was known to be positive for human T-lymphotropic virus I antibody before death. This is the first electron microscopy report on a patient from an endemic tropical spastic paraparesis region.

The role of HTLV-I in tropical spastic paraparesis in Jamaica

We report clinical and laboratory investigations of 47 native-born Jamaican patients with endemic tropical spastic paraparesis and of 1 patient with tropical ataxic neuropathy. Mean age at onset was 40 years, with a female-male preponderance (2.7:1). Neurological features of endemic tropical spastic paraparesis are predominantly those of a spastic paraparesis with variable degrees of proprioceptive and/or superficial sensory impairment. Using enzyme-linked immunoabsorbent assay (ELISA), IgG antibodies to human T-lymphotropic virus type I (HTLV-I) were present in 82% of sera and 77% of cerebrospinal fluids. On Western blot analysis, IgG antibodies detected the p19 and p24 gag-encoded core proteins in both serum and cerebrospinal fluid. Titers were tenfold higher by ELISA in serum than in cerebrospinal fluid, and some oligoclonal bands present in fluid were not seen in serum. Serum-cerebrospinal fluid albumin ratios were normal, and IgG indexes indicated intrathecal IgG synthesis. Histopathological changes showed a chronic inflammatory reaction with mononuclear cell infiltration, perivascular cuffing, and demyelination that was predominant in the lateral columns. In 1 patient, a retrovirus morphologically similar to HTLV-I on electron microscopy was isolated from spinal fluid. Our investigations show that endemic tropical spastic paraparesis in Jamaica is a retrovirus-associated myelopathy and that HTLV-I or an antigenically similar retrovirus is the causal agent.

Pathological and immunological observations on tropical spastic paraparesis in patients from Jamaica

The neuropathological examination of the spinal cord of 2 Jamaican patients with classical tropical spastic paraparesis disclosed an intense chronic meningomyelitis with demyelination. In the 1 case in which serum and cerebrospinal fluid were available, antibodies to the human T-lymphotropic virus type 1 were found.

Intrathecal synthesis of IgG antibodies to HTLV-I supports an etiological role for HTLV-I in tropical spastic paraparesis

High titers of antibody to human T-lymphotropic virus type I (HTLV-I) have been reported in the sera and cerebrospinal fluids of patients with tropical spastic paraparesis. By means of agarose isoelectric focusing and selective immunoblotting, we demonstrated oligoclonal bands of immunoglobulin G antibodies to HTLV-I in the serum and cerebrospinal fluid of patients with tropical spastic paraparesis. Such cerebrospinal fluid-specific immunoglobulin bands indicate intrathecal synthesis of specific antibodies to HTLV-I. These findings mimic the antibody response to measles virus in subacute sclerosing panencephalitis and support an etiological role for HTLV-I in the pathogenesis of tropical spastic paraparesis.

Immunological findings in neurological diseases associated with antibodies to HTLV-I: activated lymphocytes in tropical spastic paraparesis

A retrovirus involvement in the etiology of certain neurological diseases is currently an area of intense interest. Tropical spastic paraparesis and other chronic progressive myelopathies have been clearly associated with increased serum and cerebrospinal fluid antibody titers to human T-lymphotropic virus type I; however, little is known about the cellular immune response. In the present study, activated T-lymphocytes were found in the peripheral blood of patients with this disorder. There were increased numbers of large CD3-positive cells that also expressed histocompatibility leukocyte Class II (DR) and interleukin 2-receptor molecules. In addition, a significantly elevated spontaneous lymphoproliferative response was demonstrated in all patients. This is consistent with the known in vitro effects of human T-lymphotropic virus type I. In one patient, a defect in the generation of measles virus-specific cytotoxic T cells was identified. These observations indicate abnormalities of the cellular immune response in tropical spastic paraparesis.

Epidemiology of tropical spastic paraparesis in Columbia and associated HTLV-I infection

The clinical syndrome earlier designated as paraparesia espástica del Pacífico is an isolated form of tropical spastic paraparesis (TSP) that was reported in 1981 in the southern Pacific lowlands of Columbia in and near Tumaco. The clinical features are similar to those of TSP reported in Jamaica, Martinique, the Seychelles, and the Ivory Coast of Africa and resemble also those clinical features of the human T-lymphotropic virus type I (HTLV-I)-associated myelopathy described in southern Japan. Since HTLV-I infection is closely associated with TSP, we conducted a case-control study to evaluate the role of HTLV-I-associated risk factors among patients from the endemic focus in Tumaco, Colombia, and the seroprevalence rates of this virus in other geographical areas of the Pacific Colombian lowlands with and without TSP. From our seroprevalence study of antibodies to HTLV-I among TSP index patients, matched controls, household contacts (first- and second-degree relatives), and healthy controls from these areas, we found a strong association between HTLV-I and TSP. Also, there is a high seroprevalence of HTLV-I among sexual partners of patients and to a lesser extent among their offspring and other relatives some of whom had an early mean acquisition of antibodies to HTLV-I. Heterosexual promiscuity and other close interpersonal contact may play an important role in the transmission of TSP in the Pacific lowlands of Colombia.

Seroprevalence of antibodies to HTLV-I in patients with chronic neurological disorders other than tropical spastic paraparesis

Human T-lymphotropic virus type I (HTLV-I), the etiological agent of adult T-cell leukemia/lymphoma, also appears to be the cause of tropical spastic paraparesis, a chronic myelopathy reported in several different regions of the world. The prevalence of antibodies to HTLV-I in patients with chronic neurodegenerative disorders other than tropical spastic paraparesis and in patients with some muscle inflammatory disorders has been investigated. IgG antibodies to HTLV-I were measured in the sera and/or cerebrospinal fluid from 82 Guamanian patients with amyotrophic lateral sclerosis and parkinsonism-dementia, 164 Guamanian normal controls, 10 patients with kuru from the Eastern Highlands of Papua New Guinea, 4 patients with Viliuisk encephalomyelitis from the Iakut region of eastern Siberia, 45 Italian patients with multiple sclerosis, and 56 patients with polymyositis (49 from the United States and 7 from Jamaica). As determined by enzyme-linked immunosorbent assay, Western immunoblot, and gelatin particle agglutination techniques, serological evidence of HTLV-I infection was found in 1 patient with amyotrophic lateral sclerosis and 1 control subject from Guam, and in 1 patient from the United States and all 7 Jamaican patients with polymyositis. Except for the high seropositivity rate among the group of Jamaican patients with polymyositis, our data indicate that HTLV-I is an unlikely causative agent in the spectrum of the neurological diseases examined. The seropositivity of the 7 Jamaican patients with polymyositis requires further study.

Persistent infection of chimpanzees with human immunodeficiency virus: serological responses and properties of reisolated viruses

Persistent infection by human immunodeficiency virus (HIV-1) in the chimpanzee may be valuable for immunopathologic and potential vaccine evaluation. Two HIV strains, the tissue culture-derived human T-cell lymphotropic virus type IIIB (HTLV-IIIB) and in vivo serially passaged lymphadenopathy-associated virus type 1 (LAV-1), were injected intravenously into chimpanzees. Two animals received HTLV-IIIB as either virus-infected H9 cells or cell-free virus. A third animal received chimpanzee-passaged LAV-1. Evaluation of their sera for virus-specific serologic changes, including neutralizations, was done during a 2-year period. During this period all animals had persistently high titers of antibodies to viral core and envelope antigens. All three animals developed a progressively increasing type-specific neutralizing LAV-1 versus HTLV-IIIB antibody titer during the 2-year observation period which broadened in specificity to include HTLV-HIRF, HTLV-IIIMN, and HTLV-IIICC after 6 to 12 months. The antibody titers against both viruses were still increasing by 2 years after experimental virus inoculation. Sera from all animals were capable of neutralizing both homologously and heterologously reisolated virus from chimpanzees. A slightly more rapid type-specific neutralizing response was noted for the animal receiving HTLV-IIIB-infected cells compared with that for cell-free HTLV-IIIB. Sera from all persistently infected chimpanzees were capable of mediating group-specific antibody-mediated complement-dependent cytolysis of HIV-infected cells derived from all isolates tested. Viruses reisolated from all three animals at 20 months after inoculation revealed very similar peptide maps of their respective envelope gp120s, as determined by two-dimensional chymotrypsin oligopeptide analysis. One peptide, however, from the original HTLV-IIIB-inoculated virus was deleted in viruses from all three animals, and in addition, we noted the appearance of a new or modified peptide which was common to LAV-1 as well as to HTLV-IIIB reisolated from infected chimpanzees. It thus appears that a group-specific neutralizing antibody response as well as a group-specific cytotoxic response can develop in chimpanzees after an inoculation of a single HIV variant. This finding suggests that a common, less immunodominant determinant(s) is present on a single HIV strain which could induce group-specific antibodies during viral infection and replication. The identification of this group-specific epitope and the induction of analogous immunity may be relevant to vaccine development against human acquired immunodeficiency syndrome.