CD4 and CD8 lymphocyte subsets in cerebrospinal fluid and peripheral blood from patients with multiple sclerosis,...

To study the distribution of CD4+ and CD8+ T-cell subsets in cerebrospinal fluid (CSF) and peripheral blood from patients with multiple sclerosis (MS), meningitis, other neurological diseases and healthy controls.

The expression of markers for naive and memory cells (CD45RA+ and CD45R0+), and helper/inducer cells (CD29+) on CD4+ cells as well as CD45R0+ and killer/effector (S6F1+) on CD8+ cells was investigated in cerebrospinal fluid (CSF) and peripheral blood from patients with multiple sclerosis (n=28), meningitis (n=13), other neurological diseases (n=16), and healthy controls (n=16) by 2-color flow cytometry.

The majority of T cells in the CSF of the 4 groups exhibited the phenotype of memory cells (CD45R0+) on both CD4+ and CD8+ cells. The proportion of helper/inducer (CD29+CD4+ in CD4+) cells was also larger in the CSF compared to peripheral blood in the 3 patient groups and controls investigated. In contrast, CD8+ cells with killer/effector (S6F1+) phenotype were fewer in CSF compared to peripheral blood in all 4 groups. There were no significant differences between patients and controls regarding the distribution of these activation markers in the CSF or peripheral blood.

Our observations support the notion that activated T cells of both CD4+ and CD8+ phenotype selectively pass the blood-brain barrier under both pathological and normal conditions.