Motor behavioral abnormalities and histopathological findings of Wistar rats inoculated with HTLV-1-infected MT2 cells

The objective of the present study was to describe motor behavioral changes in association with histopathological and hematological findings in Wistar rats inoculated intravenously with human T-cell lymphotropic virus type 1 (HTLV-1)-infected MT2 cells. Twenty-five 4-month-old male rats were inoculated with HTLV-1-infected MT2 cells and 13 control rats were inoculated with normal human lymphocytes. The behavior of the rats was observed before and 5, 10, 15, and 20 months after inoculation during a 30-min/rat testing time for 5 consecutive days. During each of 4 periods, a subset of rats was randomly chosen to be sacrificed in order to harvest the spinal cord for histopathological analysis and to obtain blood for serological and molecular studies. Behavioral analyses of the HTLV-1-inoculated rats showed a significant decrease of climbing, walking and freezing, and an increase of scratching, sniffing, biting, licking, and resting/sleeping. Two of the 25 HTLV-1-inoculated rats (8%) developed spastic paraparesis as a major behavioral change. The histopathological changes were few and mild, but in some cases there was diffuse lymphocyte infiltration. The minor and major behavioral changes occurred after 10-20 months of evolution. The long-term observation of Wistar rats inoculated with HTLV-1-infected MT2 cells showed major (spastic paraparesis) and minor motor abnormalities in association with the degree of HTLV-1-induced myelopathy.

Clinical and immunological features of patients with atopy and concomitant HTLV-1 infection

Human T-cell lymphotropic virus type 1 (HTLV-1) induces an exacerbated type 1 immune response characterized by high spontaneous IFN-γ and TNF-α production. Allergic rhinitis and asthma are associated with the type 2 immune response, with elevated secretion of IL-4 and IL-5. The aim of this study was to characterize the immune response in atopic HTLV-1 carriers. The cytokine profile of atopic HTLV-1 carriers (N = 10; all females) was compared with that of non-atopic HTLV-1 carriers (N = 14; 9 females and 5 males). Mean patient age of atopic and non-atopic groups was 45 ± 8 and 38 ± 11 years, respectively. All atopic HTLV-1 carriers had rhinitis with or without asthma and a skin prick test positive for Dermatophagoides pteronyssinus antigen 1 (Derp-1). There was no difference in cytokine levels between the two groups in unstimulated peripheral blood mononuclear cell cultures. In cultures stimulated with Derp-1, IFN-γ levels tended to be higher (P = 0.06) and IL-5 levels were higher (P = 0.02) in atopic HTLV-1 patients than in non-atopic subjects. In contrast, IL-10 was lower (P = 0.004) in atopic than in non-atopic HTLV-1-infected subjects. This study shows that HTLV-1 infection with an exaggerated type 1 immune response does not prevent atopy. In this case, the exacerbated type 1 and type 2 immune responses were due to a lack of IL-10 production, a cytokine that plays an important role in down-modulating type 1 and type 2 immune responses and in preventing the development of chronic inflammatory diseases.

Mayaro virus: imported cases of human infection in São Paulo State, Brazil

Mayaro virus (MAYV) is an arbovirus (Togaviridae: Alphavirus) enzootic in tropical South America and maintained in a sylvan cycle involving wild vertebrates and Haemagogus mosquitoes. MAYV cases occur sporadically in persons with a history of recent activities inside or around forests. This paper reports three cases of MAYV fever detected in men infected in Camapuã, MS, Brazil. Serum samples collected at four days and two months after the onset of the symptoms and examined by hemagglutination inhibition test, revealed monotypic seroconversion to MAYV. Isolation of the virus was obtained from one of the samples by inoculation of the first blood samples into newborn mice. A suspension of the infected mouse brain was inoculated into C6/36 cells culture and the virus was identified by indirect immunofluorescent assay with alphavirus polyclonal antibodies. RT-PCR, performed with RNA extracted from the supernatant of C6/36 infected cells in the presence of alphavirus generic primers as well as specific MAYV primers, confirmed these results. The reported cases illustrate the importance of laboratory confirmation in establishing a correct diagnosis. Clinical symptoms are not always indicative of a disease caused by an arbovirus. Also MAYV causes febrile illness, which may be mistaken for dengue.

Enhanced anti-tumor effect of a gene gun-delivered DNA vaccine encoding the human papillomavirus type 16 oncoproteins genetically fused to the herpes simplex virus glycoprotein D

Anti-cancer DNA vaccines have attracted growing interest as a simple and non-invasive method for both the treatment and prevention of tumors induced by human papillomaviruses. Nonetheless, the low immunogenicity of parenterally administered vaccines, particularly regarding the activation of cytotoxic CD8+ T cell responses, suggests that further improvements in both vaccine composition and administration routes are still required. In the present study, we report the immune responses and anti-tumor effects of a DNA vaccine (pgD-E7E6E5) expressing three proteins (E7, E6, and E5) of the human papillomavirus type 16 genetically fused to the glycoprotein D of the human herpes simplex virus type 1, which was administered to mice by the intradermal (id) route using a gene gun. A single id dose of pgD-E7E6E5 (2 µg/dose) induced a strong activation of E7-specific interferon-γ (INF-γ)-producing CD8+ T cells and full prophylactic anti-tumor effects in the vaccinated mice. Three vaccine doses inhibited tumor growth in 70% of the mice with established tumors. In addition, a single vaccine dose consisting of the co-administration of pgD-E7E6E5 and the vector encoding interleukin-12 or granulocyte-macrophage colony-stimulating factor further enhanced the therapeutic anti-tumor effects and conferred protection to 60 and 50% of the vaccinated mice, respectively. In conclusion, id administration of pgD-E7E6E5 significantly enhanced the immunogenicity and anti-tumor effects of the DNA vaccine, representing a promising administration route for future clinical trials.

Severity score system for progressive myelopathy: development and validation of a new clinical scale

Progressive myelopathies can be secondary to inborn errors of metabolism (IEM) such as mucopolysaccharidosis, mucolipidosis, and adrenomyeloneuropathy. The available scale, Japanese Orthopaedic Association (JOA) score, was validated only for degenerative vertebral diseases. Our objective is to propose and validate a new scale addressing progressive myelopathies and to present validating data for JOA in these diseases. A new scale, Severity Score System for Progressive Myelopathy (SSPROM), covering motor disability, sphincter dysfunction, spasticity, and sensory losses. Inter- and intra-rater reliabilities were measured. External validation was tested by applying JOA, the Expanded Disability Status Scale (EDSS), the Barthel index, and the Osame Motor Disability Score. Thirty-eight patients, 17 with adrenomyeloneuropathy, 3 with mucopolysaccharidosis I, 3 with mucopolysaccharidosis IV, 2 with mucopolysaccharidosis VI, 2 with mucolipidosis, and 11 with human T-cell lymphotropic virus type-1 (HTLV-1)-associated myelopathy participated in the study. The mean ± SD SSPROM and JOA scores were 74.6 ± 11.4 and 12.4 ± 2.3, respectively. Construct validity for SSPROM (JOA: r = 0.84, P < 0.0001; EDSS: r = -0.83, P < 0.0001; Barthel: r = 0.56, P < 0.002; Osame: r = -0.94, P < 0.0001) and reliability (intra-rater: r = 0.83, P < 0.0001; inter-rater: r = 0.94, P < 0.0001) were demonstrated. The metric properties of JOA were similar to those found in SSPROM. Several clinimetric requirements were met for both SSPROM and JOA scales. Since SSPROM has a wider range, it should be useful for follow-up studies on IEM myelopathies.

Viremic blood donor found by a rapid screening method in a season of high human parvovirus B19 activity in Niterói, Rio de Janeiro, Brazil

Erythrovirus B19 infection is usually benign but may have serious consequences in patients with hemolytic anemia (transient aplastic crisis), immunodeficiency (in whom persistent infection can lead to chronic bone marrow failure with anemia), or who are in the first or second trimester of gestation (spontaneous abortion, hydrops fetalis, and fetal death). Being non-enveloped, B19 resists most inactivation methods and can be transmitted by transfusion. B19 is difficult to cultivate and native virus is usually obtained from viremic blood. As specific antibodies may be absent, and there is no reliable immunological method for antigen detection, hybridization or polymerase chain reaction are needed for detecting viremia. A rapid method, gel hemagglutination (Diamed ID-Parvovirus B19 Antigen Test), can disclose highly viremic donations, whose elimination lessens the viral burden in pooled blood products and may even render them non-infectious. In order to obtain native antigen and to determine the frequency of viremic donors, we applied this test to blood donors in a period of high viral activity in our community. Positive or indeterminate results were re-tested by dot-blot hybridization. We tested 472 donors in 1998 and 831 ones in 1999. One viremic donor was found in 1999. We suggest that in periods of high community viral activity the gel hemagglutination test may be useful in avoiding highly viremic blood being added to plasma pools or directly transfused to patients under risk.

Duplex-PCR assay for the detection of adenovirus and respiratory syncytial virus in nasopharyngeal samples

Human adenovirus (HAdV) and human respiratory syncytial virus (HRSV) are important etiologic agents of acute respiratory infections. In this study, a duplex polymerase chain reaction (PCR) assay was developed for the simultaneous detection of HAdV and HRSV in clinical samples. Sixty previously screened nasopharyngeal aspirates were used: 20 HAdV-positive, 20 HRSV-positive and 20 double-negative controls. Eight samples were positive for both viruses. The duplex PCR assay proved to be as sensitive and specific as single-target assays and also detected the mixed infections with certainty. The identification of both viruses in a single reaction offers a reduction in both cost and laboratory diagnostic time.

The Rio de Janeiro HIV Vaccine Site: I. Recruitment Strategies and Socio-demographic Data of a HIV Negative Homosexual and Bisexual Male Cohort in Rio de Janeiro, Brazil

The initial effort of the Brazilian Ministry of Health to be an active partner in the world effort in the preparation of future accurate human immune deficiency virus (HIV) efficacy trials was the establishment of a multi-centered cohort of homosexual and bisexual men. An open cohort was established to determine the HIV incidence and the socio-behavioral aspects involved in Rio de Janeiro. A total of 318 potential participants, originated from multiple sources (health units, public information, snowball recruitment), were screened and recruitment became effective through the direct involvement of target communities (with the support of Non Governmental Organizations) and the population. Among this group, seropositivity for sexually transmitted diseases was high with 23, 32 and 46% for HIV, syphilis and hepatitis B, respectively. The socio-demographic data from the first 200 participants of this HIV negative cohort suggests that the cohort volunteers are an appropriate sample of the general male population of the State of Rio de Janeiro

Emerging animal viruses: real threats or simple bystanders?

The list of animal viruses has been frequently added of new members raising permanent concerns to virologists and veterinarians. The pathogenic potential and association with disease have been clearly demonstrated for some, but not for all of these emerging viruses. This review describes recent discoveries of animal viruses and their potential relevance for veterinary practice. Dogs were considered refractory to influenza viruses until 2004, when an influenza A virus subtype H3N8 was transmitted from horses and produced severe respiratory disease in racing greyhounds in Florida/USA. The novel virus, named canine influenza virus (CIV), is considered now a separate virus lineage and has spread among urban canine population in the USA. A new pestivirus (Flaviviridae), tentatively called HoBi-like pestivirus, was identified in 2004 in commercial fetal bovine serum from Brazil. Hobi-like viruses are genetically and antigenically related to bovine viral diarrhea virus (BVDV) and induce similar clinical manifestations. These novel viruses seem to be widespread in Brazilian herds and have also been detected in Southeast Asia and Europe. In 2011, a novel mosquito-borne orthobunyavirus, named Schmallenberg virus (SBV), was associated with fever, drop in milk production, abortion and newborn malformation in cattle and sheep in Germany. Subsequently, the virus disseminated over several European countries and currently represents a real treat for animal health. The origin of SBV is still a matter of debate but it may be a reassortant from previous known bunyaviruses Shamonda and Satuperi. Hepatitis E virus (HEV, family Hepeviridae) is a long known agent of human acute hepatitis and in 1997 was first identified in pigs. Current data indicates that swine HEV is spread worldwide, mainly associated with subclinical infection. Two of the four HEV genotypes are zoonotic and may be transmitted between swine and human by contaminated water and undercooked pork meat. The current distribution and impact of HEV infection in swine production are largely unknown. Avian gyrovirus type 2 (AGV2) is a newly described Gyrovirus, family Circoviridae, which was unexpectedly found in sera of poultry suspected to be infected with chicken anemia virus (CAV). AGV2 is closely related to CAV but displays sufficient genomic differences to be classified as a distinct species. AGV2 seems to be distributed in Brazil and also in other countries but its pathogenic role for chickens is still under investigation. Finally, the long time and intensive search for animal relatives of human hepatitis C virus (HCV) has led to the identification of novel hepaciviruses in dogs (canine hepacivirus [CHV]), horses (non-primate hepaciviruses [NPHV] or Theiler's disease associated virus [TDAV]) and rodents. For these, a clear and definitive association with disease is still lacking and only time and investigation will tell whether they are real disease agents or simple spectators.

Genetic analysis of the porcine group B rotavirus NSP2 gene from wild-type Brazilian strains

Group B rotaviruses (RV-B) were first identified in piglet feces, being later associated with diarrhea in humans, cattle, lambs, and rats. In human beings, the virus was only described in China, India, and Bangladesh, especially infecting adults. Only a few studies concerning molecular analysis of the RV-B NSP2 gene have been conducted, and porcine RV-B has not been characterized. In the present study, three porcine wild-type RV-B strains from piglet stool samples collected from Brazilian pig herds were used for analysis. PAGE results were inconclusive for those samples, but specific amplicons of the RV-B NSP2 gene (segment 8) were obtained in a semi-nested PCR assay. The three porcine RV-B strains showed the highest nucleotide identity with the human WH1 strain and the alignments with other published sequences resulted in three groups of strains divided according to host species. The group of human strains showed 92.4 to 99.7% nucleotide identity while the porcine strains of the Brazilian RV-B group showed 90.4 to 91.8% identity to each other. The identity of the Brazilian porcine RV-B strains with outer sequences consisting of group A and C rotaviruses was only 35.3 to 38.8%. A dendrogram was also constructed to group the strains into clusters according to host species: human, rat, and a distinct third cluster consisting exclusively of the Brazilian porcine RV-B strains. This is the first study of the porcine RV-B NSP2 gene that contributes to the partial characterization of this virus and demonstrates the relationship among RV-B strains from different host species.

T CD4+ cells count among patients co-infected with human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus type 1 (HTLV-1): high prevalence of tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM)

INTRODUCTION: HIV positive patients co-infected with HTLV-1 may have an increase in their T CD4+ cell counts, thus rendering this parameter useless as an AIDS-defining event. OBJECTIVE: To study the effects induced by the co-infection of HIV-1 and HTLV-1 upon CD4+ cells. MATERIAL AND METHODS: Since 1997, our group has been following a cohort of HTLV-1-infected patients, in order to study the interaction of HTLV-1 with HIV and/or with hepatitis C virus (HCV), as well as HTLV-1-only infected asymptomatic carriers and those with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM). One hundred and fifty HTLV-1-infected subjects have been referred to our clinic at the Institute of Infectious Diseases "Emílio Ribas", São Paulo. Twenty-seven of them were also infected with HIV-1 and HTLV-1-infection using two ELISAs and confirmed and typed by Western Blot (WB) or polymerase chain reaction (PCR). All subjects were evaluated by two neurologists, blinded to the patient's HTLV status, and the TSP/HAM diagnostic was based on the World Health Organization (WHO) classification. AIDS-defining events were in accordance with the Centers for Disease Control (CDC) classification of 1988. The first T CD4+ cells count available before starting anti-retroviral therapy are shown compared to the HIV-1-infected subjects at the moment of AIDS defining event. RESULTS: A total of 27 HIV-1/HTLV-1 co-infected subjects were identified in this cohort; 15 already had AIDS and 12 remained free of AIDS. The median of T CD4+ cell counts was 189 (98-688) cells/mm³ and 89 (53-196) cells/mm³ for co-infected subjects who had an AIDS-defining event, and HIV-only infected individuals, respectively (p = 0.036). Eight of 27 co-infected subjects (30%) were diagnosed as having a TSP/HAM simile diagnosis, and three of them had opportunistic infections but high T CD4+ cell counts at the time of their AIDS- defining event. DISCUSSION: Our results indicate that higher T CD4+ cells count among HIV-1/HTLV-1-coinfected subjects was found in 12% of the patients who presented an AIDS-defining event. These subjects also showed a TSP/HAM simile picture when it was the first manifestation of disease; this incidence is 20 times higher than that for HTLV-1-only infected subjects in endemic areas.

Prevalence of human T cell leukemia virus-I (HTLV-I) antibody among populations living in the Amazon region of Brazil (preliminary report)

Forty-tree (31.4%) out of 137 serum samples obtained from two Indian communities living in the Amazon region were found to be positive for HTLV-I antibody, as tested by enzyme-linked immunosorbent assay (Elisa). Eighty-two sera were collected from Mekranoiti Indians, yielding 39% of positivity, whereas 11 (20.0%) or the 55 Tiriyo serum samples had antibody to HTLV-I. In addition, positive results occurred in 10 (23.2%) out of 43 sera obtained from patients living in the Belem area, who were suffering from cancer affecting different organs. Five (16.7%) out of 30 Elisa positive specimens were also shown to be positive by either Western blot analysis (WB) or indirect immunogold electron microscopy (IIG-EM).

Socio-demographic and epidemiological characteristics associated with human immunodeficiency virus type I (HIV-1) infection in HIV-1-explosed but uninfected individuals, and in HIV-1-infected patients from a southern brasilian population

The ability to control human immunodeficiency virus type 1 (HIV-1) infection and progression of the disease is regulated by host and viral factors. This cross-sectional study describes the socio-demographic and epidemiological characteristics associated with HIV-1 infection in 1,061 subjects attended in Londrina and region, south of Brazil: 136 healthy individuals (Group 1), 147 HIV-1-exposed but uninfected individuals (Group 2), 161 HIV-1-infected asymptomatic patients (Group 3), and 617 patients with AIDS (Group 4). Data were obtained by a standardized questionnaire and serological tests. The age of the individuals ranged from 15.1 to 79.5 years, 54.0% and 56.1% of the Groups 3 and 4 patients, respectively, were men. The major features of groups 2, 3, and 4 were a predominance of education level up to secondary school (55.8%, 60.2% and 62.4%, respectively), sexual route of exposure (88.4%, 87.0% and 82.0%, respectively), heterosexual behavior (91.8%, 75.2% and 83.7%, respectively), and previous sexually transmitted diseases (20.4%, 32.5%, and 38.1%, respectively). The patients with AIDS showed the highest rates of seropositivity for syphilis (25.6%), of anti-HCV (22.3%), and anti-HTLV I/II obtained by two serological screening tests (6.2% and 6.8%, respectively). The results documenting the predominant characteristics for HIV-1 infection among residents of Londrina and region, could be useful for the improvement of current HIV-1 prevention, monitoring and therapeutic programs targeted at this population.

Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA)

The human lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA), were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

Coinfection by Strongyloides stercoralis in blood donors infected with human T-cell leukemia/lymphoma virus type 1 in São Paulo city, Brazil

The frequency of coinfection with Strongyloides stercoralis and human T-cell leukemia/lymphoma virus type 1 (HTML-1) was determined in 91 blood donors examined at the blood bank of a large hospital in São Paulo city, Brazil. As control group 61 individuals, not infected by HTLV-1, were submitted to the same techniques for the diagnosis of S. stercoralis infection. In HTLV-1 infected patients the frequency of S. stercoralis infection was 12.1%; on the other hand, the control group showed a frequency significantly lower of S. stercoralis infection (1.6%), suggesting that HTLV-1 patients shoud be considered as a high risk group for strongyloidiasis in São Paulo city.