Many studies using IHC, ISH or real-time polymerase chain reaction (RT-PCR) on samples from the CNS of dead MS patients at different stages of the disease revealed the presence of immediate-early proteins and/or immediate-early genes, suggesting the presence of a lytic cycle in the CNS of MS patients in addition to the presence of B-cells in latent phase as seen previously with LMP1 and LMP2A. The gene discussed is PDLIM7; the disease is myeloid sarcoma.