Intramuscular inoculation of Sin Nombre hantavirus cDNAs induces cellular and humoral immune responses in BALB/c mice.

To examine whether genetic immunization with Sin Nombre (SN) hantavirus genes could elicit immune responses, nine fragments spanning the envelope glycoprotein genes G1 and G2, and the complete N gene were cloned into a CMV expression vector. To ensure representation of all potential epitopes, adjacent fragments of the glycoprotein genes overlapped one another by 100 nucleotides. Vectors containing the gene fragments were inoculated intramuscularly into BALB/c mice and splenocyte proliferation and western blot-detectable antibodies and neutralization titers were determined. The N gene and seven of the nine M segment-derived cDNAs tested produced significant specific lymphoproliferative responses, and many of the constructs elicited either neutralizing or western blot-detectable antibodies. These promising results encourage the development of infection models for SN virus that will be capable of detecting protective responses.