The adjuvanticity of Chiococca alba saponins increases with the length and hydrophilicity of their sugar chains

► We examine four different Chiococca alba saponins containing 2, 3 and 4 sugar units. ► The best adjuvant potential was found in the four sugar units-saponin called CA4. ► CA4 was used for vaccination with the FML antigen of Leishmania donovani. ► CA4 induced a CD4+-TNF-α mediated protection against murine visceral leishmaniasis. ► Adjuvanticity increases with the length and hydrophilicity of saponins sugar chains.