Abstracts (complete list) - Wissenschaft Online

Christian Hofmann, Thomas Harrer, Kathrin Eismann, Silke Bergmann, Matthias Schmitt-
Haendle, Gerold Schuler, Jan Dörrie, Niels Schaft
REPROGRAMMING T CELLS WITH A HIV-1-SPECIFICTY BY
ELECTROPORATION OF TCR-ENCODING RNA
HIV-1 establishes a persistent infection in humans and destroys the patient’s CD4+
immune cells, which ultimately leads to paralysis of the immune system. However, high
levels and a broad specificity of anti-HIV-1 CD8+ cytotoxic T lymphocytes (CTL),
especially against conserved epitopes, are considered to be critical for long-term control
of HIV-1 replication. Unfortunately, most HIV-infected patients are unable to generate
such a powerful immune response. A possible immunotherapy is the adoptive transfer
of T cells, which were reprogrammed by introduction of an HIV-specific T cell receptor
(TCR). Until now, these HIV-specific CTL were generated by retroviral transduction of
TCR encoding cDNA. However, this strategy harbors the threat of stable genetic
alteration of autologous cells. Therefore, we studied TCR transfer by RNA
electroporation into CD8+ T cells. An HIVpol-specific TCR, which recognizes the HLA-A2
restricted peptide ILKEPVHGV, was used. These reprogrammed T cells produced the proinflammatory
cytokines IL-2, TNF, and IFNgamma after stimulation with peptide-loaded
target cells, and efficiently and specifically killed these targets, even after
cryopreservation. The cytolytic function of the reprogrammed T cells persisted for at
least 72 h after transfection. Peptide-titration studies revealed that the lytic avidity of
the TCR-RNA-electroporated CD8+ T cells was in the same range as that of the parental
CTL clone. Taken together, we show here for the first time that functional transfer of
virus-specific TCR by RNA electroporation is feasible. This technology represents an
innovative, secure, and easy method to produce virus-specific T cells, and may
represent a new tool in the fight against HIV infection.