Effect of monophosphoryl lipid A on antibody response to diphtheria toxin and its subunits

Abstract

Monophosphoryl lipid A (MPL) was evaluated for its ability to enhance the antibody response to diphtheria toxin and its fragment A and fragment B subunits. BALB/c mice were immunized subcutaneously with 1 Lf of diphtheria toxoid in the presence of 25 microg of MPL on days 0 and 14. Two weeks after the second immunization, sera were obtained from the mice and analysed for antibody response to diphtheria toxin and its subunits. A new ELISA method, developed in our laboratory, was used to measure antibody levels against the toxin, fragment A, and fragment B. It was observed that MPL significantly enhanced antibody responses to diphtheria toxin and its subunits. However, there was no statistical difference between anti-A and anti-B responses. The results indicated that MPL seems to be a potential candidate as an adjuvant for future diphtheria vaccine formulation.

Evaluation of human antibody responses to diphtheria toxin subunits A and B in various age groups

“…The samples gave a gel pattern consistent with the known molecular sizes of intact diphtheria toxin, diphtheria subunit A and diphtheria subunit B [10].…”

“…The in-house double-antigen ELISA was performed as described previously [10,12]. The results obtained with the double-antigen ELISA correlate well with those obtained using the toxin neutralisation assay [13].…”

“…Diphtheria toxin was fragmented into subunits A and B as described previously [10]. In brief, the toxin was treated with freshly dissolved trypsin for 15 min at 37°C in 50 mM TrisHCl, 1 mM EDTA, pH 8.2.…”

Effect of Tape Stripping and Adjuvants on Immune Response After Intradermal DNA Electroporation

“…It has been widely used as an adjuvant in various vaccine formulations (20,21). MPLA is thought to function through activation of TLR 2 and TLR 4 for the induction of TNF-α, IL-10, and IL-12 (22).…”

Avaliação de adjuvantes em novas formulações de vacina tríplice bacteriana.

“…Caglar et al (2005) a imunização de camundongos com toxóide diftérico na presença de MPL (derivado de LPS de Salmonella minnesota Re595) induziu altos níveis de anticorpos contra toxina diftérica, sugerindo que o MPL pode ser um candidato potencial como adjuvante Estrutura química do lipídeo A (A) e do monofosforil lipídeo A (B), ambos de Salmonella minnesota. A seta aberta indica o grupo fosfato e a seta fechada indica a cadeia lateral, estruturas retiradas após extração orgânica do monofosforil lipídeo A. FONTE: Figura A modificadade Feulner, 2003 e figura B modificadade Persing et al, 2002.…”