Dominant T-cell epitopes of filarial BmALT-2 and their cytokine profile in BALB/c mice.

Filarial nematodes down-regulate the host immune response to establish infection by inducing IL-10-mediated T-cell suppression.Abundant larval transcript (ALT) proteins are of major interest as they are expressed abundantly in the L3 stage, implicated in protective immunity and may play a role in immune evasion. The T-cell epitopes of BmALT-2 and the cytokine responses induced by these peptides were investigated in a mouse model using synthetic peptides, which could be exploited in the design of a potent epitope-based vaccine. Five regions were found to carry T-cell epitopes inducing high levels of cellular proliferation. The regions 55­68 and 73­91 of ALT-2 induced very high levels of IL-10 secretion and hence could be involved in immunomodulation in the host.