Isolation and characterization of CD8+ regulatory T cells in multiple sclerosis

To investigate CD8+ regulatory T cell influence on multiple sclerosis development, peripheral blood and cerebrospinal fluid (CSF) CD8+ T cell clones (TCCs) recognizing MBP_83–102 and MOG_63–87-specific CD4+ T cells were isolated from 20 patients during acute exacerbations, 15 in remission and 15 controls. Blood and CSF CD8+ regulatory TCC cloning frequency decreased more during exacerbations than remissions or controls. Target cell pre-activation significantly enhanced CD8+ T granule-mediated cell killing of CD4+ targets, and was restricted by HLA-E. During exacerbations, killer-inhibitory receptor CD94/NKG2A expression was significantly higher in CD8+ TCCs, limiting their cytotoxic activity. Moreover, IL-15 and IFN-γ significantly increased CD94 and NKG2A expression. These data provide evidence that CD94/NKG2A receptors play an important role in regulating T cell activity during the course of MS.     

Evidence for a missed signal to the CD8+ cells in CSF of Multiple Sclerosis patients

Peripheral blood (PB) and cerebrospinal fluid (CSF) lymphocyte subpopulations, defined by various T-cell specific monoclonal antibodies and flow cytometry, were analysed in 44 relapsing remitting multiple sclerosis (RRMS) patients (including 21 subjects in the acute phase and 23 in the stable phase), 40 chronic-progressive multiple sclerosis (CPMS) patients, and 24 patients with other neurological diseases (OND), in order to verify the presence of any abnormality in the lymphocyte subset pattern. A significant increase in the total number of T-lymphocytes and the CD4+ subpopulation was found in the PB of the MS patients in comparison with the OND group. Moreover, a not statistically significant increase in CD4⁺ cells was observed in the CSF of MS patients. A statistically significant increase was also found in the CD4⁺ Leu 8⁺ (suppressor inducer) cells in the CSF of all of the MS groups. Finally, the CD8⁺ (suppressor/cytotoxic) cell levels, were significantly lower in the CSF of CPMS and stable RMS patients than in the CSF of the OND patients. As a whole, our data suggest that the immunosuppressive deficit that seems to be a constant finding in MS is not due to a decrease in suppressor inducer cell levels, as previously suggested, but may be caused by a missed or altered signal from the suppressor inducer to CD8⁺ suppressor cells.This Work was partially supported by an IRCCS Current Research Grant 1994.     

Mononuclear cell types in cerebrospinal fluid and blood of patients with multiple sclerosis. Quantitation by immunoenzyme microassay with panel of monoclonal antibodies

Phenotypic distribution of mononuclear cells in cerebrospinal fluid (CSF) and peripheral blood from patients with multiple sclerosis (MS) and, for reference, patients with acute aseptic meningoencephalitis (AM), and in blood only from healthy controls, was studied with an immunoenzymatic microassay enabling analysis even in the presence of a normal CSF cell count. In MS, increased CD5+ (pan-T) cell proportion in CSF compared with blood was not reflected by changes of CD4+ or CD8+ cells, while in AM, an increase of CD4+ cells was registered. Therefore, a population of CD5+, CD4-, and CD8- cells may be anticipated to exist in CSF of patients with MS. Numbers of OKB7+, OKM1+, or HLA-DR+ cells did not distinguish between MS and AM. Proliferating cells expressing transferrin receptors (OKT9+ cells) were generally few or absent in CSF and not useful as a marker of disease activity in either MS or AM.     

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 CD45RO⁺), and helper/inducer cells (CD29⁺) on CD4⁺ cells as well as CD45RO⁺ 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 (CD45RO⁺) on both CD4⁺ and CD8⁺ cells. The proportion of helper/inducer (CD29TD4⁺ 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.     

CD8 high CD11b low T cells (T suppressor-effectors) in multiple sclerosis cerebrospinal fluid are increased during high dose corticosteroid treatment

Using simultaneous dual direct immunofluorescence the effect of high dose intravenous methylprednisolone on the expression of T lymphocyte differentiation antigens in paired cerebrospinal fluid and peripheral blood samples of nine clinically active patients with multiple sclerosis was studied. Corticosteroid treatment was associated with a clinical improvement in eight out of the nine patients. In cerebrospinal fluid of all patients the treatment was associated with a decrease of CD3+, CD4+ and CD8+ T cells, and of intra-central nervous system IgG synthesis. CD8+ high CD11b+ low suppressor-effector T cells behaved differently in the eight patients who improved with treatment, where they significantly increased, and in the patient without clinical response, where they were almost unchanged. Similar phenotypic changes were found in peripheral blood, and all changes returned towards baseline after treatment. The lower sensitivity to corticosteroids of CD8+ high CD11b+ low T cells could change the balance between immunoregulatory T subsets. In this study the increased availability of a subpopulation mainly composed of T cells with a suppressor-effector function was associated with a clinical response to treatment.     

CD4+ lymphocyte subsets in the cerebrospinal fluid of multiple sclerosis and non-inflammatory neurological diseases

Summary We studied paired cerebrospinal fluid (CSF) and peripheral blood (PB) samples from 18 inactive multiple sclerosis (MS) patients and 10 with non-inflammatory neurological diseases. By means of a dual-colour cytofluorimetric micromethod we were able to count 1500 cells on average in each CSF sample. We found a significant reduction of CD45RA+ and CD4+CD45RA+ cells in the CSF of MS patients. Similarly, CD45RA+ and CD4+CD45RA+ CSF/PB ratios were lower compared with controls. The reduction of suppressor-inducer T-cells did not correlate with CD8+ cell levels in the CSF. The CD4+ subset ratio (CD4+CD45RA–/CD4+CD45RA+) was significantly increased in the CSF of MS patients. Our data suggest that the reduction of CD4+CD45RA+ cells in the PB is not due to a segregation of such cells in the CSF. Conversely, CSF changes reflect changes in the PB similar to these found for other T-cell subsets.     

Increased numbers of mononuclear cells from blood and CSF expressing interferon-gamma mRNA in multiple sclerosis are from both the CD4+ and the CD8+ subsets

Activated, cytokine-producing lymphocytes may regulate central nervous system (CNS) inflammation in multiple sclerosis (MS). We utilize a novel combination of in situ hybridization (ISH) and immunocytochemical staining of peripheral blood lymphocytes (PBLs) to identify spontaneously interferon-gamma (IFNgamma) mRNA expressing cells as CD4+ or CD8+. A major proportion of the IFNgamma mRNA expressing lymphocytes belonged to the CD4+ lineage, which concords with the cellular composition of MS brain lesions, findings in experimental models and the HLA class II haplotype association in MS. There were also significantly more CD8+ IFNgamma mRNA expressing lymphocytes in the MS patients compared with healthy controls, further suggesting the contribution of activated cells from this lineage in the inflammatory response in MS. Both CD4+ and CD8+ IFNgamma mRNA expressing cells were enriched in the cerebrospinal fluid (CSF) as compared with the peripheral blood of the MS patients. Combined with emerging genetic data on HLA class I influences, our data argues for a joint role of activated CD8+ and CD4+ cells in the pathogenesis of MS.     

Interferon-beta-1a treatment increases CD56 natural killer cells and CD4+CD25+ Foxp3 expression in subjects with multiple sclerosis

Disease modifying effects of interferon (IFN)-β therapy in patients with multiple sclerosis (MS) may be mediated in part through enhanced immunoregulation by the CD56^bright subpopulation of natural killer (NK) cells and by Foxp3+ (not italicized) CD4+CD25+ regulatory T cells (Treg). We found that IFN-β-1a(IM) treatment of relapsing–remitting (RR)MS subjects over 12 months significantly increased both percentage of CD56^bright NK cells and Foxp3 mRNA expression compared to baseline values, untreated RRMS subjects and healthy controls (HC). This striking enhancement of two prominent immunoregulatory pathways lends support to the idea that beneficial effects of IFN-β-1a in MS include control of pernicious autoimmunity.     

Analysis of CD27 surface expression on T cell subsets in MS patients and control individuals

Within the peripheral blood, CD4⁺CD27⁻ T cells only reside within the CD45RAT ⁻(memory or primed) T cell subset. Cells with this phenotype have characteristics of specialized effector T cells according to their cytokine secretion profiles and the expression of tissue-specific adhesion molecules. This subset was previously found to be increased in certain diseases that are associated with immune activation. Therefore we analyzed CD27 expression of peripheral blood and CSF T cells in MS patients. Within the CD4⁺ T cell subset no differences were seen between MS patients and controls in proportions of CD45RA⁻CD27⁻ cells. However, when the CD3⁺ T cell compartment was analyzed, CD27⁻ cells were also found within the CD45RA⁺ subset. These cells, most likely CD8⁺, are significantly reduced in PBL and CSF of MS patients as compared with OND patients. In MS and OND groups the level of CD27⁻ cells in peripheral blood correlated significantly with that in CSF, indicating a balanced migration of CD27⁻ cells between the two compartments. In OIND patients, however, this equilibrium was lost. The correlation of the level of CD27⁺ cells with the amount of intrathecally produced IgG in MS patients may suggest that CD27⁺ cells are responsible for B cell help in this disease.     

Role of perforin secretion from CD8+ T-cells in neuronal cytotoxicity in multiple sclerosis

Objectives: Multiple sclerosis (MS) is the most prevalent autoimmune disease of the central nervous system, and is characterized by inflammation and myelin damage. The immune system initiates the autoimmune response, although the mechanisms of neuronal damage have not been elucidated. The purpose of the present study was to investigate autoreactive CD4+ and CD8⁺ T lymphocytes, in conjunction with other inflammatory cells and cytokines in active MS lesions.

Methods: EAE animal models was established by plantar injections of MBP (200 μg per rat). Purified CD4+ or CD8+ T-cells were isolated from heparinized peripheral blood (EAE animals and control animals) via negative selection. To examine effects of presence of autoreactive CD4+ and CD8+ T lymphocytes, we carried out ELISA, Western blot analysis and TUNEL. In addition, we examined the direct effects of various factors on neuronal cell death using MTT assay.

Results: The data revealed that CD8+ T-cells were more toxic to neurons compared to CD4+ T-cells, in both the MBP and EAE conditions. Bax was greater increased when neurons were co-cultured with CD8+ T-cells in the MBP group. There is a significant increase in IL-17 secretion by CD4+ T-cells in both the MBP group and EAE group. Neuronal viability were affected by Perforin (1.5 μg/mL).

Conclusion: The present study extends previous research by demonstrating the role of CD8+ T-cells in MS and supports perforin secretion by CD8+ T-cells as a potential therapeutic factor. Furthermore, we determined that CD4⁺ T-cells can enhance CD8⁺ T-cell neuronal cytotoxicity via induction of intense inflammation.     

The activation of memory CD4(+) T cells and CD8(+) T cells in patients with multiple sclerosis

To reevaluate whether an association exists between the clinical course of multiple sclerosis (MS) and the activation of memory T cells, we investigated the phenotype of T cells in peripheral blood and cerebrospinal fluid (CSF) of patients with MS using five-color flow cytometry. A cross-sectional study with 39 relapsing-remitting MS patients demonstrated that the percentage of CD25(+)CD45RO(+)CD4(+)CD3(+) cells was significantly increased in peripheral blood as well as in CSF of active MS patients compared with inactive MS patients. A longitudinal study with 11 relapsing-remitting MS patients also showed a higher percentage of CD25(+)CD45RO(+)CD4(+)CD3(+) cells in peripheral blood at the phase of exacerbation than during remission. On the other hand, regardless of the disease activity, the percentage of CD25(+)CD45RO(+)CD8(+)CD3(+) cells in peripheral blood was significantly higher in patients with MS than in healthy control subjects. A lower percentage of CD25(+)CD45RO(+)CD8(+)CD3(+) cells in CSF was observed in active MS patients compared with inactive MS patients. These results suggest that the activation of memory CD4(+) T cells is associated with the exacerbation of MS and activation of memory CD8(+) T cells reflects systemic immunological dysregulation in MS patients. Transient as well as continuous activation of T cells by recall antigens may be involved in the disease course of MS.     

Synthesis of anti-acetylcholine receptor antibodies by CD5- B cells from peripheral blood of myasthenia gravis patients

An increased frequency of CD5⁺ B cells (or, according to a new nomenclature, B 1 cells) has been detected in the peripheral blood of a proportion of patients with myasthenia gravis (MG), as in some other autoimmune diseases. To elucidate the pathogenic significance of this B-cell subset in myasthenia gravis, mononuclear cells from the peripheral blood of six MG patients were separated into T and B lymphocytes by a magnetic cell separation procedure employing superparamagnetic microbeads (MACS). Subsequently, the B-cell fraction was depleted of CD5⁺ B cells in a second separation. The resulting purified CD5^– B-cell fraction was cultured alone or with the addition of autologous T cells. Anti-acetylcholine receptor (AChR) synthesis by CD5^– B cells in cultures with T cells was significantly increased by pokeweed mitogen (176 ±130 fmol/ml per week/2 × 10⁵ B cells) compared with unfractionated cells (75 ± 101) or CD5^– B cells alone (19 ± 4). These results demonstrate that in MG anti-AChR are synthesized, at least in part, by CD5^– B cells which are dependent on T cells. Although this does not exclude the existence of AChR-specific CD5⁺ B cells, it provides evidence against a pivotal role of this B-cell subset in anti-AChR synthesis.     

Apoptosis of T cells in peripheral blood and cerebrospinal fluid is associated with disease activity of multiple sclerosis

Apoptotic elimination of pathogenic T cells is considered to be one of regulatory mechanisms in multiple sclerosis (MS). To explore the potential relationship between Fas-mediated apoptosis and the disease course of MS, we examined apoptosis, defined by annexin V (AV) binding, and Fas (CD95) expression in CD4+ and in CD8+ T cells in MS patients by using five-color flow cytometry. The percentage of AV+CD4+CD3+ cells and CD95+AV+CD4+CD3+ cells in peripheral blood and cerebrospinal fluid (CSF) were significantly decreased in active MS patients compared with inactive MS patients. A significantly lower proportion of CD95+AV+CD8+CD3+ cells in CSF was observed in active MS patients compared with inactive MS patients, but not in peripheral blood. These results indicate that the resistance of T cells to Fas-mediated apoptosis is involved in exacerbation of MS and/or that Fas-mediated apoptosis of T cells is associated with remission of MS.     

Functional assay for human CD4+CD25+ Treg cells reveals an age-dependent loss of suppressive activity

CD4+CD25+ regulatory T cells (Treg cells) prevent T cell-mediated autoimmune diseases in rodents. To develop a functional Treg assay for human blood cells, we used FACS- or bead-sorted CD4+CD25+ T cells from healthy donors to inhibit anti-CD3/CD28 activation of CD4+CD25- indicator T cells. The data clearly demonstrated classical Treg suppression of CD4+CD25- indicator cells by both CD4+CD25(+high) and CD4+CD25(+low) T cells obtained by FACS or magnetic bead sorting. Suppressive activity was found in either CD45RO- (naive) or CD45RO+ (memory) subpopulations, was independent of the TCR signal strength, required cell-cell contact, and was reversible by interleukin-2 (IL-2). Of general interest is that a wider sampling of 27 healthy donors revealed an age- but not gender-dependent loss of suppressive activity in the CD4+CD25+ population. The presence or absence of suppressive activity in CD4+CD25+ T cells from a given donor could be demonstrated consistently over time, and lack of suppression was not due to method of sorting, strength of signal, or sensitivity of indicator cells. Phenotypic markers did not differ on CD4+CD25+ T cells tested ex vivo from suppressive vs. nonsuppressive donors, although, upon activation in vitro, suppressive CD4+CD25+ T cells had significantly higher expression of both CTLA-4 and GITR than CD4+CD25- T cells from the same donors. Moreover, antibody neutralization of CTLA-4, GITR, IL-10, or IL-17 completely reversed Treg-induced suppression. Our results are highly consistent with those reported for murine Treg cells and are the first to demonstrate that suppressive activity of human CD4+CD25+ T cells declines with age.     

Differential expression of heat shock proteins by human glial cells

Heat shock proteins (HSP) have been implicated in the interactions between the gamma delta T lymphocyte population and target tissues. gamma delta T cells are found in increased numbers in multiple sclerosis (MS) plaques compared to their proportion in peripheral blood, co-localizing with oligodendrocytes (OGC) expressing HSP. We have demonstrated that such gamma delta T cells can induce in vitro lysis of human adult-derived OGC. Using immunohistochemical and flow cytometry techniques, we examined the constitutive and/or inducible expression of HSP in or on adult human-derived glial cell cultures in vitro. HSP70 was expressed in OGC maintained at basal temperature, but the expression of the inducible HSP70 protein was upregulated by a prior 43 degrees C heat exposure. HSP70 could not be detected within astrocytes (GFAP+ cells), whether heat stress was applied or not. Constitutive expression of HSP60 could be discerned on the surface of all OGC under non-stressed culture conditions. Only some astrocytes demonstrated minor punctate surface HSP60 staining, whereas the remainder did not express HSP60 constitutively. These observations raise the possibility that OGC, by virtue of their differential expression of HSP compared to other glial cells, may be particularly prone to interaction with HSP-reactive gamma delta T cells. Such findings may further implicate gamma delta T cells in the pathogenesis of MS, a putative autoimmune disease in which immune-mediated injury is directed specifically against the oligodendrocyte-myelin unit within the central nervous system.     

Expression of costimulatory molecules on peripheral blood mononuclear cells in multiple sclerosis

OBJECTIVE: To determine whether there was aberrant expression of costimulatory molecules and their receptors on peripheral blood mononuclear cells of MS patients and healthy individuals and whether expression correlated with disease status. METHODS: Forty-six patients with MS and 29 healthy individuals were analyzed by direct 2-color immunofluorescence flow cytometry for expression of CD80, CD86, CD28 and CTLA-4 on T and B cells and monocytes. RESULTS: Expression of CD80 on CD4+ T cells was upregulated in progressing MS patients compared to stable MS patients and controls. Marked increase in the expression of CD80 and CD86 was seen on both CD4+ and CD8+ T cells from an MS patient with rapidly progressing disease. No difference in the expression of the costimulatory molecules or their ligands was seen between IFN-beta treated and non-treated MS patients. CONCLUSIONS: Aberrant expression of costimulatory molecules occurs on T lymphocytes in MS patients with progressing disease.     

Altered CD4+/CD8+ T-cell ratios in cerebrospinal fluid of natalizumab-treated patients with multiple sclerosis

BACKGROUND: Treatment with natalizumab, a monoclonal antibody against the adhesion molecule very late activation antigen 4, an alpha4beta(1) integrin, was recently associated with the development of progressive multifocal leukoencephalopathy, a demyelinating disorder of the central nervous system caused by JC virus infection. OBJECTIVE: To test the effect of natalizumab treatment on the CD4(+)/CD8(+) T-cell ratios in cerebrospinal fluid (CSF) and peripheral blood. DESIGN: Prospective longitudinal study. SETTING: Academic and private multiple sclerosis centers. PATIENTS: Patients with multiple sclerosis (MS) treated with natalizumab, untreated patients with MS, patients with other neurologic diseases, and human immunodeficiency virus-infected patients. MAIN OUTCOME MEASURES: CD4(+) and CD8(+) T cells were enumerated in CSF and peripheral blood. The mean fluorescence intensity of unbound alpha4 integrin on peripheral blood CD4(+) and CD8(+) T cells was analyzed before and after natalizumab therapy. RESULTS: Natalizumab therapy decreased the CSF CD4(+)/CD8(+) ratio of patients with MS to levels similar to those of human immunodeficiency virus-infected patients. CD4(+)/CD8(+) ratios in peripheral blood in patients with MS progressively decreased with the number of natalizumab doses, but they remained within normal limits. Six months after the cessation of natalizumab therapy, CSF CD4(+)/CD8(+) ratios normalized. The expression of unbound alpha4 integrin on peripheral blood T cells decreases with natalizumab therapy and was significantly lower on CD4(+) vs CD8(+) T cells. CONCLUSIONS: Natalizumab treatment alters the CSF CD4(+)/CD8(+) ratio. Lower expression of unbound alpha4 integrin on CD4(+) T cells is one possible mechanism. These results may have implications for the observation that some natalizumab-treated patients with MS developed progressive multifocal leukoencephalopathy.     

Restricted T cell receptor delta chain genes repertoire in peripheral blood of multiple sclerosis patients

Multiple sclerosis (MS) is a chronic inflammatory disease characterized by focal demyelination of central nervous system (CNS). Susceptibility to MS is thought to be affected by multiple genes including HLA and T cell receptor (TCR) genes. In view of the recent evidence, that in addition to α/β T lymphocytes also γ/δ T cells may have autoreactive potential, TCR delta repertoire in peripheral blood of MS patients has been studied. TCR delta repertoire, as assessed by Vδ-Jδ rearrangements, has been analysed in 13 MS cases and in 30 healthy individuals by seminested PCR technique. Oligonucleotide primers specific for six Vδ regions and for Jδ1 gene were used for amplification of Vδ-Jδ junctional region responsible for the diversity of γ/δ TCR. In the majority of MS patients PAGE analysis of Vδ1-Jδ1, Vδ3-Jδ1 and Vδ5-Jδ1 rearrangements showed single-band or two-band pattern. The most striking result has been observed in Vδ5-Jδ1 rearrangement, where in nine cases studied single band and in four patients two bands have been found. In all but one MS cases multi-band pattern of Vδ2-Jδ1 rearrangement was obtained. None of the 13 MS patients showed single-band rearrangement pattern of Vδ4-Jδ1 and Vδ6-Jδl. Contrary to the MS group almost all healthy individuals produced smear-like or multi-band pattern of Vδ1-Vδ5 to Jδ1 rearrangements. On the basis of the banding pattern produced by Vδ-Jδ rearrangement in MS, it can be suggested that T lymphocytes had undergone clonal expansion in vivo, most likely due to stimulation by antigen related to CNS. In particular a very consistent single-band pattern of Vδ5-Jδ1 rearrangement observed in almost all MS patients studied, argues very strongly for a significant role of γ/δ T cells with Vδ5 rearrangement in the pathogenesis of MS. However, it cannot be excluded that the observed patterns of TCR δ gene rearrangement in MS patients may represent secondary changes to CNS damage.     

多发性硬化患者CD8+记忆性T细胞亚群穿孔素和颗粒酶-B表达的研究

目的 测定多发性硬化(MS)患者外周血中CD8+记忆性T细胞亚群效应细胞因子的表达,并将其与MS病情严重程度进行相关分析.方法 利用四色-流式细胞术检测未经治疗的MS患者、其他神经系统疾病(OND)患者和正常对照(NC)成员组外周血表达穿孔素和颗粒酶-B的CD8+记忆性T细胞亚群数量,并利用扩展的残疾状况量表(EDSS)对MS患者病情严重程度做评分.结果 与NC组比较,MS患者外周血表达颗粒酶-B的CD8+效应记忆性T细胞(TEM)和终末效应记忆性T细胞(TerTEM)均明显减少,比较差异有统计学意义(P＜0.05);表达穿孔素和颗粒酶-B的TEM数量与EDSS呈负相关(r=-0.493,P=0.027;r=-0.594,P=0.009).结论 CD8+TEM参与MS相关的CNS内炎性免疫应答,外周血穿孔素和颗粒酶-B表达阳性的CD8+TEM数量可在一定程度上反映MS患者CNS的病损程度.     

Chemokine receptor expression on T cells in blood and cerebrospinal fluid at relapse and remission of multiple sclerosis: imbalance of Th1/Th2-associated chemokine signaling

The expression of chemokine receptors on lymphocytes in the blood and CSF of multiple sclerosis (MS) patients was analyzed at relapse and remission. Both CD4+ and CD8+ cells in CSF at relapse were enriched for Th1-type receptors CXCR3 and CCR5 expression, and were reduced for Th2-type receptors CCR3 and CCR4 expression compared with those of the blood. CCR1 and CCR2 expressions on T cells were increased in CSF and blood, respectively. At remission, CCR5 expression, but not CXCR3 expression, was reduced in CSF CD4+ cells. A biased Th1/Th2 balance may play a critical role in active inflammation and CCR5 on CSF CD4+ cells is a good marker of the disease activity.