MARCELO ANDREETTA CORRAL
Projetos de Pesquisa
Unidades Organizacionais
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- Immunoreactivity of proteins within 30-40 kDa range during the acute and the recovery phases in rats experimentally infected with Strongyloides venezuelensis(2020) FONSECA, Priscilla Duarte Marques; CORRAL, Marcelo Andreeta; MEISEL, Dirce Mary C. Lima; LEVI, Debora; NASCIMENTO, Rafael Correa; CASTRO-BORGES, William; GRYSCHEK, Ronaldo; COSTA-CRUZ, Julia Maria; PAULA, Fabiana Martins deIn experimental infection with Strongyloides venezuelensis, the acute and recovery phases can be distinguished, unlike human infections caused by Strongyloides stercoralis. The objective of this study was to evaluate the production of anti-Strongyloides IgG antibodies and the recognition of immunogenic protein bands during the acute and the recovery phases in rats experimentally infected with S. venezuelensis. Rats were infected subcutaneously with 400 or 4,000 S. venezuelensis infective larvae. The acute phase was characterized by elimination of a large number of eggs in the faeces on days 6-14 post infection; the recovery phase was characterized by the resolution of the infection between days 30 and 35 post infection. Differences in IgG levels were observed in the acute and the recovery phases. Different antigenic fractions were recognized in both phases of infection. It is concluded that proteins within the 30-40 kDa range are immunoreactive markers for both the acute and the recovery phases in rats experimentally infected with S. venezuelensis, particularly using membrane antigen.
- Strongyloides infection screening in transplant candidates: What is the best strategy?(2023) GRYSCHEK, Ronaldo Cesar Borges; CORRAL, Marcelo Andreetta; SITTA, Renata Barnabe; GOTTARDI, Maiara; PIERROTTI, Ligia Camera; COSTA, Silvia Figueiredo; ABDALA, Edson; CHIEFFI, Pedro Paulo; PAULA, Fabiana Martins deBackground: The potential that Strongyloides stercoralis infection has to cause major morbidity and high mortality when the disseminated form occurs in transplant patients is of particular concern.Methods: In this study, the objective was to observe S. stercoralis infection in patients who are candidates for transplantation by using parasitological, serological, and molecular techniques and to propose an algorithm for the detection of that infection in transplant candidates.Results: By parasitological techniques, 10% of fecal samples were positive. Anti-Strongyloides antibodies immunoglobulin G were detected in 19.3% and 20.7% of patients by immunofluorescence assay and enzyme-linked immunosorbent assay, respectively. S. stercoralis DNA was observed in 17.3% of samples by conventional polymerase chain reaction and 32.7% of samples by quantitative polymerase chain reaction (qPCR).Conclusion: The set of results allows us to reinforce that a positive result by parasitological techniques and/or qPCR indicates that the specific treatment should be applied. However, the improvement of diagnostic techniques may suggest changes in the screening for strongyloidiasis in these patients. image
- Toxocara canis 30-35 kDa excretory-secretory antigen is an important marker in mice challenged by inocula containing different parasite load levels(2022) FONSECA, Gabriela Rodrigues e; CORRAL, Marcelo Andreetta; PAULA, Fabiana Martins de; MEISEL, Dirce Mary Correia Lima; GRYSCHEK, Ronaldo Cesar Borges; LESCANO, Susana Angelica ZevallosThe Western-blotting technique was applied to identify antigenic fractions of excretory-secretory Toxocara canis antigen recognized by IgG antibodies throughout an experimental infection in mice challenged by different inocula. Mice were inoculated with 5, 50 and 500 embryonated eggs and serum samples were collected 15, 30, 60, 90 and 120 days post-infection. Serum samples were analyzed using an excretory-secretory Toxocara antigen. Antibodies recognized antigenic fractions from 30 to 90 kDa. The protein fraction of 30-35 kDa was the most frequently recognized regardless of the size of inoculum and the stage of infection represented by the different collection times, but the antigenic recognition was more evident in groups infected with 50 and 500 eggs. This study presents an antigenic panel of the excretory secretory antigen of T. canis and suggests that the 30-35 kDa antigenic fraction is a promising marker of the infection and should be further explored in future studies on experimental toxocariasis.
- Evaluation of the Dot-ELISA as a diagnostic test for human strongyloidiasis based on the detection of IgA in saliva(2020) BOSQUI, Larissa Rodrigues; CORRAL, Marcelo Andreetta; LEVY, Debora; BYDLOWSKI, Sergio Paulo; GRYSCHEK, Ronaldo Cesar Borges; CUSTODIO, Luiz Antonio; PAVANELLI, Wander Rogerio; CONCHON-COSTA, Ivete; COSTA-CRUZ, Julia Maria; PAULA, Fabiana Martins de; COSTA, Idessania NazarethThis study aimed to evaluate the use of saliva samples in the Dot-ELISA test for immunodiagnosis of human strongyloidiasis. The Dot-ELISA presented similar results to the ELISA test, with 70% and 60% sensitivity and 85% and 90% specificity, respectively, for IgA in the saliva. The Dot-ELISA with alternative saliva samples may be a suitable tool for diagnosing human strongyloidiasis, especially in populations with high levels of exposure to helminth.
- Immunofluorescence assay for diagnosis of strongyloidiasis in immunocompromised patients(2015) GOTTARDI, Maiara; PAULA, Fabiana M.; CORRAL, Marcelo A.; MEISEL, Dirce Mary C.; COSTA, Silvia F.; ABDALA, Edson; PIERROTTI, Ligia C.; YAMASHIRO, Juliana; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo Cesar B.Background: Strongyloides stercoralis is a parasite that causes human strongyloidiasis. The disease ranges from asymptomatic to severe forms, which are often fatal in immunocompromised individuals. Laboratory diagnosis is challenging owing to limitations in the use of conventional parasitological techniques. The present study aimed to evaluate the indirect immunofluorescence assay (IFA) using infective larvae of S. venezuelensis as an antigen for the immunodiagnosis of human strongyloidiasis in immunocompromised patients. Methods: Serum and stool samples from 200 immunocompromised patients (HIV-positive, HTLV-1-positive, and renal, liver, and/or bone marrow transplantation candidates) were used. Stool samples were examined using three parasitological methods: Lutz, Rugai, and culture agar plate. IFA was performed using sections of infective larvae of S. venezuelensis as antigens, and showed 95.4% sensitivity and 95.8% and specificity. Results: Among the 200 patients, 17 (8.5%) were positive for S. stercoralis by at least one parasitological method, and 43 (21.5%) were positive by IFA. Conclusions: IFA can be used as a screening method for the detection of S. stercoralis in immunocompromised patients.
- Potential immunological markers for diagnosis of human strongyloidiasis using heterologous antigens(2017) CORRAL, M. A.; PAULA, F. M.; MEISEL, D. M. C. L.; CASTILHO, V. L. P.; GONCALVES, E. M. N.; LEVY, D.; BYDLOWSKI, S. P.; CHIEFFI, P. P.; CASTRO-BORGES, W.; GRYSCHEK, R. C. B.Strongyloides venezuelensis is a parasitic nematode of rodents that is frequently used to obtain heterologous antigens for immunological diagnosis of human strongyloidiasis. The aim of this study was to identify antigens from filariform larvae of S. venezuelensis for immunodiagnosis of human strongyloidiasis. Soluble and membrane fractions from filariform larvae of S. venezuelensis were obtained in phosphate saline (SS and SM) and in Tris-HCl buffer (TS and TM), and were analysed by Western blotting. Different antigenic components were recognized by IgG antibodies from the sera of strongyloidiasis patients. Highest recognition was observed for a 30-40 kDa mass range present in all antigenic fractions. The band encompassing this mass range was then excised and subjected to mass spectrometry for protein identification. Immunoreactive proteins identified in the soluble fractions corresponded to metabolic enzymes, whereas cytoskeletal proteins and galectins were more abundant in the membrane fractions. These results represent the first approach towards identification of S. venezuelensis antigens for use in immunodiagnostic assays for human strongyloidiasis.
- IgG reactivity with 40-35 kDa soluble and membrane antigen of Strongyloides venezuelensis in immunocompromised patients(2019) CORRAL, Marcelo Andreetta; PAULA, Fabiana Martins de; MEISEL, Dirce Mary C. L.; ABDALA, Edson; COSTA, Silvia Figueiredo; PIERROTTI, Ligia Camera; YAMASHIRO, Juliana; GONCALVES, Elenice M. do Nascimento; CASTILHO, Vera Lucia P.; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronald Cesar B.Immunocompromised patients constitute a risk group for the development of severe clinical forms of human strongyloidiasis. The diagnosis of this infection is primarily performed by parasitological techniques, but with low sensitivity. Serological techniques appear as an alternative, especially with heterologous antigens use. The aim of this study was to perform the Western blot technique by using S. venezuelensis infective third stage larva (iL3) soluble (TS) and membrane (TM) saline antigens to reveal immunoreactive bands in immunocompromised patients with strongyloidiasis. Serum samples from 117 parasitologically well-characterized patients were divided into four groups: S. stercoralis positive and immunocompetent (S + IC); S. stercoralis positive and immunocompromised (S + IP); negative and immunocompetent (S-IC); negative and immunocompromised (S-IP). A 40-35 kDa band was recognized by 100% of patients in the S + IC group in both antigenic fractions, and by 62.5% and 50% in the S + IP group using the TS and TM fractions, respectively. A 29 kDa band was recognized by 86.3% and 72.7% (for TS and TM, respectively) of patients in the S + IC group, and only by 12.5% of patients in the S + IP group on the TM antigen. Regardless of the patients' immunological condition, the 40-35 kDa band from S. venezuelensis was detected more frequently and can be used as an important marker to the immunodiagnosis of human strongyloidiasis.