Comparison of dot-ELISA and standard ELISA for detection of Neisseria meningitidis outer membrane complex-specific antibodies

Abstract

Dot-ELISA using the outer membrane complex antigens of Neisseria meningitidis as a target was standardized for rapid detection of meningococcal-specific antibodies in human serum. We investigated the level of meningococcal-specific IgG, IgA, and IgM in serum using dot-ELISA with outer membrane antigens prepared from Neisseria meningitidis serotype B:4.19:P1.15,3,7,9 (a strain isolated from a Brazilian epidemic). The dot-ELISA is based on the same principles as the standard ELISA and is useful for detection of anti-N. meningitidis B antibodies in serum of patients with meningococcal infections. For the assay, outer membrane complexes (OMCs) were absorbed by nitrocellulose membrane and blocked with a 5% skim milk solution. Serum samples were drawn upon hospital admission and during convalescence from patients with meningococcal septicemia, and single samples were drawn from uninfected controls. We retrospectively examined a total of 57 serum samples: 35 from patients infected with N. meningitidis B, 12 from patients infected with Haemophilus influenzae b, and 10 from health individuals. When performed at room temperature, dot-ELISA took approximately four hours to perform, and the optimum antigen concentration was 0.42 μg per dot. The specificity of IgG, IgM, and IgA demonstrates that dot-ELISA using OMCs from N. meningitidis B as a target is suitable for serologic verification of clinically suspected meningococcal disease in patients and for titer determination of antibodies produced during different phases of natural infection. Furthermore, the sensitivity of dot-ELISA was comparable to that of standard ELISA. Overall, dot-ELISA is simple to perform, rapid, and low cost. Further validation of the test as a screening tool is required.

Neisseria meningitidis: analysis of pili and LPS in emerging Brazilian strains

“…LPS mAb specificity was previously tested in our laboratory. 21 The results of Dot-ELISA show a high expression of the L3,7,9 immunotype and type IV pili. From 19 MenB strains, all were reactive to L3,7,9…”

Evaluation of IgG Avidity of Sera from Mice Immunized with RBD of SARS-CoV-2 or OMVs of Neisseria meningitidis by Immunoblot and Dot-Blot

“…This method was used for serotyping N. meningitidis outer membrane antigens using ELISA and Dot-Blot, as a practical approach for epidemiological screening [14]. In addition, our laboratory has applied in a clinical and experimental studies using Dot-Blot and Immunoblot techniques [3,33].…”