Naïve/memory phenotype of T cells in the PB and tissues of TOM. (left) The distribution of central memory, naïve and effector memory phenotypes of CD4+(A) and CD8+(B) T cells in the PB and tissues of TOM (n = 7) was determined with flow cytometry. Animals were approximately 35 weeks post-implantation on average at time of harvest. (right) Naïve T cells were defined as CD45RA+CD27+, central memory T cells (TCM) were defined as CD45RAnegCD27+, and effector memory T cells (TEM) were defined as CD45RAnegCD27neg. Error bars represent the Mean + SEM.