Phenotype analysis of unstimulated lymphocytes and anti-CD3-stimulated proliferating T-cells from cerebrospinal fluid and peripheral blood in patients with multiple sclerosis and other neurological diseases

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

OBJECTIVES

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.

MATERIAL AND METHODS

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.

RESULTS

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.

CONCLUSION

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.

Mitogenic response and steroid sensitivity in MS lymphocytes

OBJECTIVES

We investigated mitogenic response and steroid sensitivity in multiple sclerosis (MS) lymphocytes to establish if MS lymphocytes were less steroid responsive.

MATERIAL AND METHODS

We compared mitogenic response to phytohaemagglutinin (PHA) and inhibition by dexamethasone (DEX) in circulating lymphocytes from both MS patients and healthy subjects.

RESULTS

We found a range of responses in each group but no significant differences between the two groups, nor in patients with and without enhancement on magnetic resonance imaging. The mid-inhibitory concentration of DEX in response to 1 microg/ml PHA was significantly lower than that for 2.5 microg/ml PHA in the patients. The mid-inhibitory concentrations of DEX in response to 2.5 microg/ml PHA negatively correlated with endogenous serum cortisol concentrations.

CONCLUSION

These data imply a spectrum of glucocorticoid response that is similar in normal and MS lymphocytes and can partly explain why response to steroid therapy is variable.

Reduced frequency of memory CD8+ T lymphocytes in cerebrospinal fluid and blood of patients with multiple sclerosis

Three color flow cytometry was used to analyze immunoregulatory lymphocyte subsets in peripheral blood (PB) and cerebrospinal fluid (CSF) of 21 patients with multiple sclerosis (MS) and 15 age-matched healthy control subjects. Two cell surface antigens associated with T lymphocyte memory and activation, CD45R0 and CD29, were analyzed on the CD4+ and CD8+ subpopulations, respectively. A selective decrease in the expression of the CD45R0 isoform among CD8+ cells was noted in both PB (p < 0.005) and CSF (p > 0.0001) of patients with MS as compared with the control group while the expression of CD29 did not differ between the groups. These changes could indicate a defective differentiation into mature memory CD8+ T lymphocytes in patients with MS. Furthermore, the CD3+CD16/56+ T lymphocyte subset capable of mediating NK cell-like activities was investigated. Although this cell population is quantitatively small, a significant reduction of the proportion of this cell type was detected in both BP and CSF of the MS group compared with the controls (p < 0.01 and p > 0.001, respectively). Further studies are needed to establish the role of these observations in the pathogenesis of MS.