ABSTRACT
El objetivo de este trabajo es aumentar la sensibilidad de la detección de antígeno de VIH en pacientes infectados a través de un proceso de disociación de complejos inmunes que no reduzca la reactividad antigénica. Se realizó una etapa de precipitación con PEG 12 por ciento (concentración final 2 por ciento), tratamiento ácido disociante y neutralización, previo a la aplicación de un método convencional de captura de antígeno. Se mostró una relación significativa entre el tratamiento con PEG disociante y la detección de antígeno (X2: 13,97, p < 0,001). De 105 muestras, 27 sueros que resultaron negativos por el método estándar fueron positivos con el tratamiento. La cantidad de antígeno en 35 muestras previamente positivas se incrementó en promedio 2,3 veces luego del tratamiento
Subject(s)
Humans , HIV Antigens/isolation & purification , Antigen-Antibody Complex/immunology , Polyethylene Glycols , Sensitivity and Specificity , Acquired Immunodeficiency Syndrome/diagnosis , ArgentinaABSTRACT
El objetivo de este trabajo es aumentar la sensibilidad de la detección de antígeno de VIH en pacientes infectados a través de un proceso de disociación de complejos inmunes que no reduzca la reactividad antigénica. Se realizó una etapa de precipitación con PEG 12 por ciento (concentración final 2 por ciento), tratamiento ácido disociante y neutralización, previo a la aplicación de un método convencional de captura de antígeno. Se mostró una relación significativa entre el tratamiento con PEG disociante y la detección de antígeno (X2: 13,97, p < 0,001). De 105 muestras, 27 sueros que resultaron negativos por el método estándar fueron positivos con el tratamiento. La cantidad de antígeno en 35 muestras previamente positivas se incrementó en promedio 2,3 veces luego del tratamiento (AU)
Subject(s)
Humans , HIV Antigens/isolation & purification , Acquired Immunodeficiency Syndrome/diagnosis , Antigen-Antibody Complex/immunology , Polyethylene Glycols/diagnosis , Sensitivity and Specificity , ArgentinaABSTRACT
The aim of this work was to increase sensitivity in the detection of antigens from HIV-infected patients, through a process of immune complex dissociation without loss of antigenicity. 500 microliters of sera were mixed with 100 microliters of PEG 12%, stored one night in refrigerator, and centrifuged at 2000 g during 20 minutes. 200 microliters of buffer AcH/Ac- (pH 3.5) were added to the sediment, and incubated at 37 degrees C during one hour with periodic shaking. This was neutralized with 100 microliters of buffer TRIS/CIH (pH 8.6). The antigen was investigated in the original sample, supernatant and sediment. Samples of 105 patients with positive serology, confirmed by Western Blot following CDC criteria, were processed. The antigen was detected in 62 (59%) samples precipitated with PEG, but only 35 (33%) when conventional methods were used. Applying statistics X2: 13.97, P < 0.001, a highly significant association can be observed between PEG dissociation treatment and antigen detection. 27 negative sera by the standard method became positive in the whole sediment, and only 8 in the supernatant. In addition, 40 negative sera were processed, which had not become positive for the antigen by PEG treatment.
Subject(s)
Antigen-Antibody Complex/immunology , HIV Antigens/blood , HIV-1/immunology , Chemical Precipitation , False Negative Reactions , HIV Infections/blood , HIV Infections/immunology , HIV Seronegativity , HIV Seropositivity/blood , Humans , Polyethylene Glycols , Reference Standards , Sensitivity and SpecificityABSTRACT
The aim of this work was to increase sensitivity in the detection of antigens from HIV-infected patients, through a process of immune complex dissociation without loss of antigenicity. 500 microliters of sera were mixed with 100 microliters of PEG 12
, stored one night in refrigerator, and centrifuged at 2000 g during 20 minutes. 200 microliters of buffer AcH/Ac- (pH 3.5) were added to the sediment, and incubated at 37 degrees C during one hour with periodic shaking. This was neutralized with 100 microliters of buffer TRIS/CIH (pH 8.6). The antigen was investigated in the original sample, supernatant and sediment. Samples of 105 patients with positive serology, confirmed by Western Blot following CDC criteria, were processed. The antigen was detected in 62 (59
) samples precipitated with PEG, but only 35 (33
) when conventional methods were used. Applying statistics X2: 13.97, P < 0.001, a highly significant association can be observed between PEG dissociation treatment and antigen detection. 27 negative sera by the standard method became positive in the whole sediment, and only 8 in the supernatant. In addition, 40 negative sera were processed, which had not become positive for the antigen by PEG treatment.