An Evaluation Study of Enzyme-Linked Immunosorbent Assay (ELISA) Using Recombinant Protein Pap31 for Detection of Antibody against Bartonella bacilliformis Infection among the Peruvian Population

Abstract

Abstract. Reliable laboratory testing is of great importance to detect Bartonella bacilliformis infection. We evaluated the sensitivity and specificity of the enzyme-linked immunosorbent assay (ELISA) using recombinant protein Pap31 (rPap31) for the detection of antibodies against B. bacilliformis as compared with immunofluorescent assay (IFA). Of the 302 sera collected between 1997 and 2000 among an at-risk Peruvian population, 103 and 34 samples tested positive for IFA-immunoglobulin G (IgG) and IFA-IgM, respectively. By using Youden's index, the cutoff values of ELISA-IgG at 0.915 gave a sensitivity of 84.5% and specificity of 94%. The cutoff values of ELISA-IgM at 0.634 gave a sensitivity of 88.2% and specificity of 85.1%. Using latent class analysis, estimates of sensitivity and specificity of almost all the assays were slightly higher than those of a conventional method of calculation. The test is proved beneficial for discriminating between infected and non-infected individuals with the advantage of low-cost and high-throughput capability.

Detection of Mycobacterium avium Subspecies paratuberculosis (MAP) Microorganisms Using Antigenic MAP Cell Envelope Proteins

“…In general, the specificities of ELISAs with recombinant proteins reported in this study were less than that of the commercial ELISA tests. Indeed, false positive reactions with recombinant protein-based ELISAs has been reported previously ( 44 , 46 ) and considerable numbers of animals in the false positive and false negative categories are typically expected in JD diagnosis ( 47 ). In addition to the MAP-specific epitopes, it is possible that the antigens used in this study may contain other epitopes that may be present in other mycobacterial or non-mycobacterial species and environmental exposure of cattle to these microorganisms might have led to false positives.…”

Seroprevalence and risk factors for infection withBartonella bacilliformisin Loja province, Ecuador

“…For the elution of antibodies from filter paper, a 5 mm diameter punch was obtained from every dried blood sample and incubated for 2 h at room temperature in 200 µl of 0.5% Tween 20 in phosphate-buffered saline, pH 7.5 (PBST). We used a recombinant protein Pap31 (rPap31) ELISA to measure antibodies specific to B. bacilliformis 49 , 50 . To rule out cross-reactivity of the rPap31 antigen with antibodies to B. henselae and B. quintana , additional human control sera were tested.…”

Microarray of surface-exposed proteins of rickettsia heilongjiangensisfor serodiagnosis of Far-eastern spotted fever

“…The cutoff value for individual rSEPs in the microarray assay was generated as described previously using Youden’s index [ 13 ]. The reaction was considered positive if the RASIgG to one rSEP in any of the patient sera was higher than the cutoff value.…”

“…Kowalczewska et al characterized 20 rickettsial recombinant proteins by enzyme-linked immune sorbent assay (ELISA) with sera from patients infected by R. typhi or R. conorii [ 10 ], in which, many surface-exposed proteins (SEPs) like Adr2, Omp1, PLD, RickA, Sca1, Sca10, and Sca13 were used. In fact, many SEPs have been found to be suitable as diagnostic antigens, such as a 56 kDa outer membrane protein in detection of Orientia tsutsugamushi infection [ 11 , 12 ] and a surface protein Pap31 in detection of Bartonella bacilliformis infection [ 13 ]. These findings indicate that SEPs are more likely to be diagnostic candidates.…”