Abstract
The surrogate of protection against Neisseria meningitidis serogroup B (MenB) is the serum bactericidal antibody (SBA) assay, which measures the functional activity of antibody by using an exogenous complement source. Despite baby rabbit complement having been used in meningococcal serogroup A, C, Y, and W135 SBA assays, it is not recommended for use in the MenB SBA assay due to elevated SBA titers caused by low-avidity anti-MenB capsular antibody in test sera. Therefore, the possibility of absorbing anti-MenB capsular antibody from test sera to enable the use of baby rabbit complement in the MenB SBA assay was investigated by comparing the results with those gained using human complement. Colominic acid from Escherichia coli K1, which shares the same linkage residue as MenB polysaccharide, was used as an absorbent due to the commercial unavailability of purified MenB polysaccharide. Inclusion of soluble colominic acid as an absorbent with baby rabbit complement resulted in a general reduction in SBA titers compared with those obtained using baby rabbit complement alone. However, these were not comparable to human SBA titers for all samples. Further optimization and investigations demonstrated that for some samples, colominic acid reduced titers to less than those achieved with human complement, and for others, it was not possible to inhibit titers by using colominic acid. The results suggested that the use of colominic acid will not result in the ability to use baby rabbit complement in the MenB SBA assay, thus not alleviating the difficulties in procuring human complement. However, alternative absorbents, such as purified MenB polysaccharide, may warrant further evaluation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.