Aspectos sorológicos, epidemiológicos e moleculares da infecção pelo vírus da hepatite C na população da região de Londrina, Paraná, Brasil, 2001-2002

Serological, epidemiological and molecular aspects of hepatitis C virus (HCV) infection were evaluated in 183 subjects from Londrina, Paraná, Brazil, and adjacent areas. Serum samples which tested anti-HCV positive by microparticle enzyme immunoassay (MEIA) obtained from eight patients with chronic hepatitis C, 48 blood donors, and 127 patients infected with the human immunodeficiency virus (HIV) were submitted to another enzyme immunoassay (ELISA) and to the polymerase chain reaction (PCR). About 78.7% of samples were also reactive by ELISA, with the greater proportion (70.8%) of discordant results verified among blood donors. A similar finding was observed for HCV-RNA detection by PCR, with 111/165 (67.3%) positive samples, with higher rates among HIV-positive subjects and patients with chronic hepatitis than among blood donors. Sixty-one PCR-positive samples were submitted to HCV genotyping, with 77.1, 21.3 and 1.6% of the samples identified as types 1, 3 and 2, respectively. Finally, analysis of some risk factors associated with HCV infection showed that intravenous drug use was the most common risk factor among HIV/HCV co-infected patients, while blood transfusion was the most important risk factor in the group without HIV infection. The present study contributed to the knowledge regarding risk factors associated with HCV infection and the distribution of HCV genotypes in the population evaluated.Aspectos sorológicos, epidemiológicos e moleculares da infecção pelo vírus da hepatite C (HCV) foram avaliados em 183 indivíduos da região de Londrina, Paraná. Amostras soropositivas para anti-HCV pelo enzimaimunoensaio de micropartículas (MEIA), provenientes de oito pacientes com hepatite C crônica, 48 doadores de sangue e 127 indivíduos infectados pelo vírus da imunodeficiência humana (HIV), foram submetidas ao enzimaimunoensaio (ELISA) e a reação em cadeia da polimerase (PCR). Em 78,7% das amostras, verificou-se resultado reagente no ELISA, ocorrendo maior proporção de resultados discordantes entre doadores de sangue (70,8%). O mesmo ocorreu com a pesquisa do RNA viral, na qual 111/165 (67,3%) amostras foram positivas com PCR, verificando-se maior positividade entre indivíduos HIV soropositivos e pacientes com hepatite crônica do que em doadores de sangue. Em 61 amostras com viremia detectável, realizou-se a genotipagem do HCV, encontrando-se os genótipos 1 (77,1%), 3 (21,3%) e 2 (1,6%). Por fim, foram avaliados os fatores epidemiológicos em indivíduos com infecção ativa, nos quais o uso de drogas injetáveis foi o principal fator de risco encontrado em indivíduos co-infectados pelo HIV/HCV e a transfusão sangüínea foi o mais comum em indivíduos sem infecção pelo HIV. O presente estudo contribuiu para o conhecimento do perfil da infecção pelo HCV em indivíduos da nossa população e da distribuição dos genótipos do HCV nesta região

Antiparasitic antibodies occur with similar frequency in patients with clinically established multiple sclerosis with or without oligoclonal bands in the cerebrospinal fluid

The "hygiene hypothesis" postulates an inverse relationship between the prevalence of parasitic infections and the frequency of multiple sclerosis (MS). Objective: It was to study whether antibodies against parasites could be demonstrated more frequently in blood serum from MS patients with oligoclonal bands (OCB) than from MS patients without OCB. Methods: We studied serum samples from 164 patients who had previously been analyzed to investigate OCB. Parasitic antibodies were studied through unidimensional electrophoresis of proteins on polyacrylamide gel against Taenia antigens, searching for antiparasitic specific low molecular weight antibodies and also for antiparasitic nonspecific high molecular weight antibodies. Results: Two of the 103 patients with no evidence of OCB had antibodies of low molecular weight and 59 of them had antibodies of high molecular weight. Of the 61 patients with evidence of OCB, one showed antibodies of low molecular weight and 16 showed antibodies of high molecular weight. Conclusion: Antiparasitic antibodies are detected with similar frequency in MS patients with OCB and in MS patients without OCB

Imunoperoxidase para detecção de anticorpos em líquido cefalorraquiano na neurocisticercose: emprego de partículas de Cysticercus cellulosae e Cysticercus longicollis fixadas a lâminas de microscopia

The ORF strain of Cysticercus longicollis represents an important model for the study of heterologous antigens in the immunodiagnosis of neurocysticercosis (NC). The immunoperoxidase (IP) technique was standardized using a particulate antigen suspension of Cysticercus longicollis (Cl) and Cysticercus cellulosae (Cc). Cerebrospinal fluid (CSF) samples were incubated on the antigen fixed to microscopy slides; the conjugate employed was anti-IgG-peroxidase and the enzymatic reaction was started by covering the slides with chromogen solution (diaminobenzidine/H2O2). After washing with distilled water, the slide was stained with 2% malachite green in water. Of the CSF samples from 21 patients with NC, 19 (90.5%) were positive, whereas the 8 CSF samples from the control group (100%) were negative. The results of the IP-Cl test applied to 127 CSF samples from patients with suspected NC showed 28.3% reactivity as opposed to 29.1 % for the IP-Cc test. The agreement index for the IP test (Cl x Cc) was 94.2%, with no significant difference between the two antigens.A cepa ORF de Cysticercus longicollis (Cl) representa importante modelo para estudo de antígenos heterólogos no imunodiagnóstico da neurocisticercose (NC). Foi padronizada a técnica de imunoperoxidase (IP) empregando suspensão antigênica particulada. Amostras de líquido cefalorraquiano (LCR) foram incubadas sobre o antígeno fixado em lâminas de microscopia, o conjugado empregado foi anti-IgG-Peroxidase, a reação enzimática iniciou-se ao cobrirem-se as lâminas com solução cromógena (Diaminobenzidina/H2O2). Após lavagens em água destilada, a lâmina foi corada com verde malaquita a 2% em água. De 21 LCR de pacientes com NC, 19 (90,5%) foram reativos e 8 (100%) LCR do grupo controle foram não reativos. Os resultados do teste IP-Cl ensaiando 127 LCR dc pacientes com suspeita de NC mostrou 89,7% de concordância com o teste ELISA empregando extrato salino de Cysticercus cellulosae (Cc) e 94,2% de concordância com o teste IP-Cc

Taenia crassiceps cysticerci: Characterization of the 14-kDa glycoprotein with homologies to antigens from Taenia solium cysticerci

Glycoproteins from the total vesicular fluid of Taenia crassiceps (VF-Tc) were prepared using three different purification methods, consisting of ConA-lectin affinity chromatography (ConA-Tc), preparative electrophoresis (SDS-PAGE) (14gp-Tc), and monoclonal antibody immunoaffinity chromatography (18/14-Tc). The complex composition represented by the VF-Tc and ConA-Tc antigens revealed peptides ranging from 101 - to 14-kDa and from 92- to 12-kDa, respectively. Immunoblotting using lectins confirmed glucose/mannose (glc/man) residues in the 18- and 14-kDa peptides, which are considered specific and immunodominant for the diagnosis of cysticercosis, and indicated that these fractions are glycoproteins. Serum antibodies from a patient with neurocysticercosis that reacted to the 14gp band from T. crassiceps (Tc) were eluted from immunoblotting membranes and showed reactivity to 14gp from Taenia solium. In order to determine the similar peptide sequence, the N-terminal amino acid was determined and analyzed with sequences available in public databases. This sequence revealed partial homology between T. crassiceps and T solium peptides. In addition, mass spectrometry along with theoretical M(r) and pI of the 14gp-Tc point suggested a close relationship to some peptides of a 150-kDa protein complex of the T solium previously described. The identification of these common immunogenic sites will contribute to future efforts to develop recombinant antigens and synthetic peptides for immunological assays. (C) 2009 Elsevier Inc. All rights reserved.FAPESP[02-12061-0]FAPERJCNPq, BrazilCNP

Taenia solium DNA is present in the cerebrospinal fluid of neurocysticercosis patients and can be used for diagnosis

Neurocysticercosis is the most frequent parasitic infection of the CNS and the main cause of acquired epilepsy worldwide. Seizures are the most common symptoms of the disease, together with headache, involuntary movements, psychosis and a global mental deterioration. Absolute diagnostic criteria include the identification of cysticerci, with scolex, in the brain by MRI imaging. We demonstrate here, for the first time, that T. solium DNA is present in the cerebrospinal fluid of patients. The PCR amplification of the parasite DNA in the CSF enabled the correct identification of 29/30 cases (96.7 %). The PCR diagnosis of parasite DNA in the CSF may be a strong support for the diagnosis of neurocysticercosis