Immunoperoxidase for the detection for the detection of antibodies in cerebrospinal fluid in neurocysticercosis: use of Cysticercus cellulosae and Cysticercus longicollis particles fixed on microscopy slides Imunoperoxidase para detecção de anticorpos em líquido cefalorraquiano na neurocisticercose: emprego de partículas de Cysticercus cellulosae e Cysticercus longicollis fixadas a lâminas de microscopia

Abstract

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.

Keywords

• Immunoperoxidase
• Neurocysticercosis
• Cysticercus cellulosae
• Cysticercus longicollis
• Cerebrospinal fluid