@article{mbs:/content/journal/jgv/10.1099/0022-1317-79-12-2997, author = "Smith, D. J. and Iqbal, J. and Purewal, A. and Hamblin, A. S. and Edington, N.", title = "In vitro reactivation of latent equid herpesvirus-1 from CD5+/CD8+ leukocytes indirectly by IL-2 or chorionic gonadotrophin", journal= "Journal of General Virology", year = "1998", volume = "79", number = "12", pages = "2997-3004", doi = "https://doi.org/10.1099/0022-1317-79-12-2997", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-79-12-2997", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", abstract = "IL-2 and equine chorionic gonadotrophin (eCG) initiated reactivation of equid herpesvirus-1 (EHV-1) from venous lymphocytes at a frequency of 1/10 5. Indirect immunofluoresence showed that > 80% of virus-positive leukocytes were CD5 /CD8 with the remaining 20% being CD5 /CD8 /CD4 . Cocultivation demonstrated that the reactivated virus was infectious. In addition, virus was reactivated in vitro from leukocytes of > 70% of horses by the mitogens phytohaemagglutinin (PHA) and poke- weed mitogen (PWM). Transfer of supernatants showed that IL-2 and eCG acted indirectly by causing the release of other mediators from adherent cells; these mediators then reactivated EHV-1 from T cells. Blocking experiments with anti-IL-2 showed that PWM and PHA acted via IL-2 but that eCG did not. This is the first clear definition of the lymphoid cells that harbour latent EHV-1 in vivo and correlates with current RT-PCR and in situ hybridization of latency-associated transcripts in lymphocytes. This method of reactivation in vitro can be used to detect horses carrying latent EHV-1 in vivo and also has the potential to dissect the sequence of events involved in reactivation in vitro. ", }