Aluminum hydroxide associated to Schistosoma mansoni 22.6 kDa protein abrogates partial protection against experimental infection but not alter interleukin-10 production

• Main Authors: Lucila GG Pacífico, Cristina T Fonseca, Michele M Barsante, Luciana S Cardoso, Maria Ilma Araújo, Sérgio C Oliveira
• Format: Article
• Language: English
• Published: Instituto Oswaldo Cruz, Ministério da Saúde 2006-10-01
• Series: Memórias do Instituto Oswaldo Cruz.
• Subjects: Schistosoma mansoni; Sm22.6; recombinant vaccine; aluminum hydroxide; adjuvant; interleukin-10
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762006000900060

The need to develop a vaccine against schistosomiasis led several researches and our group to investigate proteins from Schistosoma mansoni as vaccine candidates. Sm22.6 is a protein from S. mansoni that shows high identity with Sj22.6 and Sh22.6 (79 and 91%, respectively). These proteins are associated with high levels of IgE and protection to reinfection. Previously, we have shown that Sm22.6 induced a partial protection of 34.5% when used together with Freund's adjuvant and produced a Th0 type of immune response with interferon-g and interleukin-4. In this work, mice were immunized with Sm22.6 alone or with aluminum hydroxide adjuvant and high levels of IgG, IgG1, and IgG2a were measured. Unfortunately, no protection was detected. Since IL-10 is a modulating cytokine in schistosomiasis, we also observed a high level of this molecule in splenocytes of vaccinated mice. In conclusion, we did not observe the adjuvant effect of aluminum hydroxide associated with rSm22.6 in protective immunity.