Immune cells after prolonged Natalizumab therapy: implications for effectiveness and safety.

BACKGROUND: Previous studies on Natalizumab (NAT) have shown increased circulation of most white blood cells (WBC) in multiple sclerosis (MS) patients shortly after its introduction. AIM: To describe peripheral immune cell phenotypes after more than 2 years of continuous NAT therapy and test for associations with clinical response to therapy. METHODS: Peripheral immune cell subsets were analyzed in 44 NAT-MS patients receiving NAT for over 24 months, and in 22 NAT-free control-MS patients. RESULTS: NAT-MS patients displayed significantly higher numbers of all WBC when compared with controls. B lymphocytes exhibited a more pronounced increase when compared with CD4+, CD8+ and NK T-cells (P = 0.011). CD4/CD8 ratio was significantly decreased in NAT-MS patients (P = 0.018) and showed no correlation with the number of NAT doses. The reduced CD4/CD8 ratio was attributable to the 'EDSS improvement' group only, irrespective of age, sex and disease severity. CONCLUSIONS: The study suggests that there is no desensitization effect after prolonged NAT exposure. A reduced CD4/CD8 ratio was associated with long-term response to therapy; thus, those patients who most benefitted from the drug might be at greater risk for opportunistic infections like progressive multifocal leucoencephalopathy (PML). We provide implications for future research for the CD4/CD8 ratio as a possible contributor to the recently developed risk stratification scheme for PML.

Functional polymorphisms of interleukin 4 and interleukin 10 may predict evolution and functional outcome of an ischaemic stroke.

BACKGROUND AND PURPOSE: Inflammatory cytokines are involved in the systemic inflammation, which precedes an ischaemic stroke (IS), and also participate into brain ischaemia-reperfusion injury. We sought to investigate whether functional polymorphisms of two anti-inflammatory molecules, interleukin (IL)4-589C>T and IL10-1082G>A, might be associated with the occurrence, clinical course and functional outcome of an acute IS. METHODS: We genotyped 290 subjects (145 consecutive IS cases and 145 age- and sex-matched controls) using a real-time PCR technology, prototypically designed for these mutations. Patients were evaluated with the Scandinavian Stroke Scale, and definitions of severity grouping and stroke progression were applied based on international agreements. Follow-up on months 1, 3, and 6 included registration of disease relapses, deaths and functional outcome measured by the Barthel Index. RESULTS: IL4-589 and IL10-1082 genotypes did not significantly differ between cases and controls. The presence of IL4-589 T allele was associated with total IS recurrences [OR (95% CI) = 3.34 (1.18-9.45)], adjusted for age, sex and conventional risk factors. IL10-1082 GG genotype was found to significantly predict early stroke progression [OR (95% CI) = 3.72 (1.28-10.76)] and functional outcome by months 1 and 3 [OR (95% CI) = 5.03 (1.15-21.94) and 5.84 (1.07-31.85), respectively], after further corrections for stroke severity and TOAST categories. CONCLUSIONS: The functional IL4-589C>T and IL10-1082G>A polymorphisms seem not to be associated with occurrence of an IS, but may predict IS relapses, progressing strokes and functional outcome, independently of conventional risk factors. Our results merit further confirmation in future studies.

Serum adiponectin acutely after an ischemic stroke: implications for a long-lasting, suppressed anti-inflammatory role.

OBJECTIVE: Past ischemic stroke (IS) patients display suppressed adiponectin (ADPN) levels a few months after disease onset. It is still unclear whether hypoadiponectinemia is already present by the early stages of stroke or occurs as a delayed effect of the acute ischemic reaction. In the present study we investigated ADPN levels acutely after an IS. MATERIALS AND METHODS: Serum ADPN was measured in 82 consecutive acute IS patients, and 30 stroke-free subjects of similar age and sex distributions. RESULTS: Patients had significantly lower ADPN levels than controls. Higher ADPN was significantly associated with reduced odds for IS accounting for age, sex and high-density lipoproteins. This association was strengthened after further adjustments for potential confounders. ADPN levels remained suppressed even 6 months after stroke. CONCLUSIONS: ADPN is significantly suppressed already by the early phases of stroke, and remains unchanged 6 months later. We propose a stable-over-time anti-inflammatory role of ADPN in IS, unrelated to the acute ischemic reaction.

T helper 1 (Th1)/Th2 cytokine expression shift of peripheral blood CD4+ and CD8+ T cells in patients at the post-acute phase of stroke.

Local humoral and cellular immune responses modulate the inflammatory processes involved in the development of atherosclerotic lesions, as well as in the evolution of brain infarcts in stroke patients. The role of systemic adaptive immunity on the progression of such disease manifestations is less clear. In the current study, we evaluated the percentages of T helper 1 (Th1) [interleukin (IL)-2, interferon (IFN)-gamma] and Th2 (IL-4, IL-10) cytokine-producing peripheral blood CD4+ and CD8+ T cells in 23 patients with a history of ischaemic stroke (IS) at the chronic stable phase of the disease (median post-stroke time 34.5 months). Seven stroke-free individuals matched for age and vascular risk factors (matched controls, MC) were collected for comparison. To measure cytokine values at baseline and after stimulation, we used a flow cytometry method of intracellular cytokine staining. Intrinsic Th1 and Th2 cytokine production in unstimulated T cells was negligible in all study participants. Following mitogenic stimulation with phorbol 12-myristate13-acetate/ionomycin, both the IS and the MC groups exhibited a similarly strong Th1 response; IL-2 production predominated in the CD4+ T cells and IFN-gamma in the CD8+ T cells. However, when measuring the Th2 cytokine-production capacity post-stimulation, a significant increase in the percentage of IL-4-producing T cells was observed in the IS groups, compared with the MC group, resulting in a significantly lower ratio of IFN-gamma-/IL-4-producing T cells. No such Th2 enhancement could be confirmed for the case of IL-10. We propose that in IS patients there is a systemic shift of the immune system towards Th2 responses at the late post-acute phase of stroke.