The development and evaluation of an ELISA for the detection of antibodies to caprine arthritis-encephalitis virus in goat sera

Abstract

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies to caprine arthritis encephalitis virus (CAEV) in goat sera. The system was evaluated using some 1500 sera from flocks of known clinical history. From this data the interpretation limits of the system were determined. The ELISA system was compared with a gel precipitin test using 5800 sera. Of the positive sera, ELISA detected 97.3% and AGPT 61%. Further evaluation was made using 60 sera of known CAEV reactivity from the USA, and results agreed 100%. Indications are that antibody to the envelope glycoprotein gp135 is being detected. The ELISA system is more sensitive than the precipitin test and is presently being used in a CAEV flock accreditation scheme.

Simple and Rapid Method for Production of Whole-Virus Antigen for Serodiagnosis of Caprine Arthritis-Encephalitis Virus by Enzyme-Linked Immunosorbent Assay

“…The production of the PEG antigen did not require the use of expensive equipment such as an ultracentrifuge or complex manipulations involved in pressure filtration, chromatography, and/or gradient centrifugation required for the production of other reported TC-derived CAEV antigen batches suitable for ELISA (2,11,20). In fact, the PEG antigen was found to be comparable to our in-house antigen used previously at our laboratory for the diagnosis of CAEV (11).…”

“…This might be because of the lack of the corresponding specific antibody in the reference polyclonal goat serum used in WB, or most probably because of degradation or loss of conformational epitopes during the antigen production and/or WB procedures. ELISAs based on whole-virus antigens have been shown to be effective for the diagnosis of CAEV-infected animals (2,11,20,25). Recombinant ELISAs have also been developed successfully with recombinant proteins derived from the trans-membrane or capsid genomic sequences regions (5,16,18).…”

“…The infection is primarily detected by the demonstration of specific CAEV antibodies in the body fluids of the infected goats (15). The agar gel immunodiffusion (AGID) assay and the enzyme-linked immunosorbent assay (ELISA) are routine serological test methods used for the serologic detection of CAEV antibodies (2,10,11,14,20,25). Antigens used for these laboratory methods are commonly extracted and purified from tissue culture (TC) infected cell material, using complex manipulation and/or expensive equipment for the purification steps (2,4,11,20,25).…”

“…The agar gel immunodiffusion (AGID) assay and the enzyme-linked immunosorbent assay (ELISA) are routine serological test methods used for the serologic detection of CAEV antibodies (2,10,11,14,20,25). Antigens used for these laboratory methods are commonly extracted and purified from tissue culture (TC) infected cell material, using complex manipulation and/or expensive equipment for the purification steps (2,4,11,20,25). Recombinant technology is also used to produce recombinant viral proteins (5,16,18).…”

Lentivírus de pequenos ruminantes (CAEV e Maedi-Visna): revisão e perspectivas

“…Em condições também experimentais, e apresentando um potencial como teste alternativo e complementar, a imunofluorescência indireta, que é recomendada pela OIE, tem sido utilizada no diagnóstico de infecção em ovinos e caprinos, utilizando-se como antígeno isolados brasileiros de SRLV (Reischak 2000). Entretanto, devido à maior sensibilidade e possibilidade de quantificação e automação, vários ensaios imunoenzimáticos (EIE) têm sido desenvolvidos para pesquisa de anticorpos, preparados a partir de antígenos do CAEV (Schroeder et al 1985, Archambault et al 1988, Heckert et al 1992, Castro et al 1999b), Maedi-Visna (Houwers et al 1982, Vitu et al 1982, Houwers & Shaake 1987, Zanoni et al 1989, ou proteína interna e/ou transmembranária recombinante do CAEV (Rimstad et al 1994, Alfonso Clavijo & Thorsen 1995 ou Maedi-Visna (Reyburn et al 1992a, Kwang & Cutlip 1992, Rosati et al 1994, Power et al 1995, Boshoff et al 1997. O uso de proteínas recombinantes tem causado problemas de resultados falso positivos, o que tem resultado na substituição desse tipo de antígeno pelos do vírus completo (Zanoni et al 1994).…”