PTPRC and Guillain-Barre syndrome: Double immunostaining for CD3 and CD45, which mark T (CD3+/CD45+) and B (CD3−/CD45+) lymphocytes, respectively, revealed the infiltration of both T and B cells in the brain of GBS-infected mice, particularly in areas such as the meninges and the choroid plexuses (Figure 2c,d).