Editors' ChoiceImmunology

For vaccines, CD4+ T cells can spell trouble

Sci. Signal.  20 Jan 2015:
Vol. 8, Issue 360, pp. ec18
DOI: 10.1126/scisignal.aaa7001

The ideal vaccine elicits immune memory—either antibodies or memory T cells—to protect the host from subsequent infections. T cell–mediated immunity requires both helper CD4+ T cells and cytotoxic CD8+ T cells to kill virus-infected cells. But what happens when a vaccine only elicits CD4+ memory T cells? Penaloza-MacMaster et al. probed this question by giving mice a vaccine that generated only memory CD4+ T cells against lymphocytic choriomeningitis virus (LCMV). Instead of protecting mice against chronic LCMV, vaccinated mice developed massive inflammation and died. Virus-specific CD8+ T cells or antibodies protected mice from the pathology. These results may have implications for vaccines against chronic viruses, such as HIV.

P. Penaloza-MacMaster, D. L. Barber, E. J. Wherry, N. M. Provine, J. E. Teigler, L. Parenteau, S. Blackmore, E. N. Borducchi, R. A. Larocca, K. B. Yates, H. Shen, W. N. Haining, R. Sommerstein, D. D. Pinschewer, R. Ahmed, D. H. Barouch, Vaccine-elicited CD4 T cells induce immunopathology after chronic LCMV infection. Science 347, 278–282 (2015). [Abstract] [Full Text]