Intrathecal production of Chlamydia pneumoniae-specific high-affinity antibodies is significantly associated to a subset of multiple sclerosis patients with progressive forms

The purpose of this study was to provide further insight into the effective relevance of the association between Chlamydia pneumoniae and MS. We evaluated by ELISA technique cerebrospinal fluid (CSF) and serum levels of anti-C. pneumoniae IgG in 46 relapsing-remitting (RR), 14 secondary progressive (SP) and 11 primary progressive (PP) MS patients grouped according to clinical and Magnetic Resonance Imaging (MRI) evidence of disease activity. Fifty-one patients with other inflammatory neurological disorders (OIND) and 52 with non-inflammatory neurological disorders (NIND) were used as controls. A C. pneumoniae-specific intrathecal IgG synthesis as detected by the relative specific index was present in a small proportion of MS (17%), OIND (22%) and NIND (2%) patients and was significantly more frequent in MS and in OIND than in NIND (p<0.001) and in SP and PP MS than in RR MS patients (p<0.02). Among the patients with C. pneumoniae-specific intratecally produced antibodies, CSF high-affinity anti-C. pneumoniae IgG were found in the majority of SP or PP MS, occasionally in OIND, but not in RR MS and NIND patients. These findings confirm that the presence of a humoral immune response to C. pneumoniae within the central nervous system (CNS) is not selectively restricted to MS, but is shared by several inflammatory neurological conditions. In addition, our results suggest that an intrathecal production of C. pneumoniae-specific high-affinity IgG can occur in a subset of patients with MS progressive forms in which a C. pneumoniae brain chronic persistent infection may play an important pathogenetic role.     

CSF levels of soluble HLA-G and Fas molecules are inversely associated to MRI evidence of disease activity in patients with relapsing-remitting multiple sclerosis

Cerebrospinal fluid (CSF) concentrations of soluble human leukocyte antigen class I (HLA-I) (sHLA-I), HLA-G (sHLA-G) and anti-apoptotic Fas (sFas) molecules were measured by enzyme linked immunosorbent assay technique in 65 relapsing-remitting (RR) MS patients classified according to clinical and magnetic resonance imaging (MRI) evidence of disease activity. Sixty-four patients with other inflammatory neurological disorders (OIND) and 64 subjects with noninflammatory neurological disorders (NIND) served as controls. CSF concentrations were higher in RRMS and in OIND than in NIND patients for sHLA-I (P < 0.02), greater in RRMS than in OIND and in NIND for sHLA-G (P < 0.001 and P < 0.01, respectively) and lower in RRMS than in OIND and in NIND for sFas (P < 0.001 and P < 0.02, respectively). An increase in CSF levels was identified in MRI active RRMS for sHLA-I (P < 0.01) and in MRI stable RRMS for sHLA-G (P < 0.01), whereas CSF values of sFas were decreased in RRMS without Gd-enhancing lesions (P < 0.02). In MS patients with no evidence of MRI disease activity, a trend towards an inverse correlation was found between CSF concentrations of sHLA-G and sHLA-I and between CSF levels of sHLA-G and sFas. Our results indicate that enhanced CSF levels of sHLA-I antigens most likely represent an indirect manifestation of intrathecal immune activation taking place in neuroinflammation. Conversely, reciprocal fluctuations in CSF sHLA-G and sFas levels observed when MRI disease activity resolved suggest that sHLA-G could play an immunomodulatory role in MS through Fas/FasL-mediated mechanisms.     

Cerebrospinal fluid and serum levels and intrathecal production of active matrix metalloproteinase-9 (MMP-9) as markers of disease activity in patients with multiple sclerosis

In this study, we employed a sensitive activity assay system to measure cerebrospinal fluid (CSF) and serum levels of active matrix metalloproteinase-9 (MMP-9) in 37 relapsing-remitting (RR), 15 secondary progressive (SP) and nine primary progressive (PP) multiple sclerosis (MS) patients, grouped according to clinical and magnetic resonance imaging (MRI) evidence of disease activity. We also studied, as neurological controls, 48 patients with other inflammatory neurological disorders (OIND) and 48 with non-inflammatory neurological disorders (NIND). To assess active MMP-9/TIMP-1 circuit, CSF and serum levels of MMP-9 tissue inhibitor TIMP-1 were quantified by ELISA in the same patient population. CSF mean levels of active MMP-9, CSF active MMP-9/TIMP-1 ratios and intrathecal active MMP-9 synthesis, as indicated by specific index, were more elevated in MS than in NIND (P < 0.05, < 0.02 and < 0.02, respectively), serum active MMP-9/TIMP-1 ratio was higher in MS (P < 0.01) and OIND (P < 0.02) than in NIND, and serum TIMP-1 concentrations were lower in MS than in NIND (P<0.05). More importantly, serum active MMP-9 mean levels, serum active MMP-9/TIMP-1 ratio and intrathecal production of active MMP-9 were increased in MS patients with clinical (P < 0.001, < 0.001 and < 0.05, respectively) and MRI (P < 0.001, < 0.001 and < 0.02, respectively) disease activity, whereas CSF mean concentrations of active MMP-9 and CSF active MMP-9/TIMP-1 ratio were enhanced only in MS patients with MRI evidence of disease activity (P < 0.02 and < 0.01, respectively). Altogether, these findings suggest that a shift in MMP-9/TIMP-1 balance towards proteolytic activity of MMP-9 could be relevant in MS immune dysregulation. In addition, our results indicate that CSF and serum levels of active MMP-9 may represent a potential surrogate biomarker for monitoring MS disease activity. In particular, serum active MMP-9/TIMP-1 ratio seems to be a very appropriate indicator of ongoing MS inflammation, since it is easily measurable.     

Chlamydia pneumoniae—specific intrathecal oligoclonal antibody response is predominantly detected in a subset of multiple sclerosis patients with progressive forms

The purpose of this study was to verify the actual involvement of Chlamydia pneumoniae in multiple sclerosis (MS) by the evaluation of its specific intrathecal humoral immune response in MS. We measured by enzyme-linked immunosorbent assay (ELISA) technique cerebrospinal fluid (CSF) and serum levels of anti-C. pneumoniae immunoglobulin G (IgG) in 27 relapsing-remitting (RR), 9 secondary progressive (SP), and 5 primary progressive (PP) MS patients, grouped according to clinical and magnetic resonance imaging (MRI) evidence of disease activity. Twenty-one patients with other inflammatory neurological disorders (OIND) and 21 with noninflammatory neurological disorders (NIND) were used as controls. Quantitative intrathecal synthesis of anti-C. pneumoniae IgG was determined by antibody-specific index (ASI), whereas the presence of C. pneumoniae—specific CSF oligoclonal IgG bands was assessed by antigen-specific immunoblotting. ASI values indicative of C. pneumoniae—specific intrathecal IgG synthesis were present in a small proportion of MS (29.3%), OIND (33.3%), and NIND (4.8%) patients and were significantly more frequent (P <.05) in total MS and in OIND than in NIND and in SP (P <.01) and PP MS (P <.05) than in RR MS. C. pneumoniae—specific CSF-restricted OCB were detected only in three SP, one PP, and one RR MS patients. These findings suggest that an intrathecal production of anti-C. pneumoniae IgG is part of humoral polyreactivity driven by MS chronic brain inflammation. However, an intrathecal release of C. pneumoniae—specific oligoclonal IgG can occur in a subset of patients with MS progressive forms in whom a C. pneumoniae— persistent brain infection may play a pathogenetic role.     

Presence of detectable levels of soluble HLA-G molecules in CSF of relapsing-remitting multiple sclerosis: relationship with CSF soluble HLA-I and IL-10 concentrations and MRI findings

We have investigated the presence of non-classical soluble HLA-G molecules (sHLA-G) in cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients and the possible relationships between CSF levels of sHLA-G, classical soluble HLA-I (sHLA-I) molecules, IL-10 amounts and Magnetic Resonance Imaging (MRI) findings were evaluated. We studied by ELISA technique the sHLA-I, sHLA-G and IL-10 levels in CSF of 50 relapsing-remitting (RR) MS patients stratified according to clinical and MRI evidence of disease activity. Thirty-six patients with other inflammatory neurological disorders (OIND) and 41 with non-inflammatory neurological disorders (NIND) were used as controls. CSF mean levels were significantly higher in MS and OIND than in NIND for sHLA-I (p<0.001) and in MS than in controls for sHLA-G (p<0.001), with no differences among the various groups for IL-10 mean concentrations. An increase in CSF sHLA-I was found in MS patients with Gd-enhancing lesions (p<0.01), while sHLA-G and IL-10 were more represented in MS patients without lesional activity on MRI scans (p<0.02). In MRI-inactive MS, CSF IL-10 mean concentrations were significantly greater in patients with CSF-detectable levels of sHLA-G than in those without any evidence of CSF sHLA-G expression (p<0.05). Our findings suggest that CSF classical sHLA-I and non-classical sHLA-G levels may modulate MS activity as assessed by MRI acting in opposite directions. The association observed between sHLA-G and IL-10 when Gd-enhancing lesion resolved indicates a potential immunoregulatory role for IL-10 in the control of MS disease activity by shifting the sHLA-I/sHLA-G balance towards sHLA-G response.     

Clinical and MRI disease activity in multiple sclerosis are associated with reciprocal fluctuations in serum and cerebrospinal fluid levels of soluble HLA class I molecules

The goal of our study was to clarify the contribution of soluble human leukocyte antigens class I (sHLA-I) in multiple sclerosis (MS) immune dysregulation. We retrospectively evaluated by ELISA cerebrospinal fluid (CSF) and serum sHLA-I levels in 79 relapsing-remitting (RR), 26 secondary progressive (SP) and 15 primary progressive (PP) MS patients stratified according to clinical and Magnetic Resonance Imaging (MRI) evidence of disease activity. One hundred and nine patients with other inflammatory neurological disorders (OIND), 88 with noninflammatory neurological disorders (NIND) and 82 healthy donors were used as controls. An intrathecal synthesis of sHLA-I detected by a specific index was significantly more consistent in MS than in controls, with more pronounced values in MS patients with relapses and MRI enhancing brain lesions. A decrease in serum sHLA-I concentrations was observed in MS patients with demyelinating attacks, while an increase in CSF levels of sHLA-I was found in MS patients with lesional activity on MRI scans. This association between intrathecal synthesis and reciprocal fluctuations of CSF and serum levels of sHLA-I in clinically and MRI active MS seems to suggest a potential role for CSF and serum levels of sHLA-I as a sensitive marker of immune activation taking place both intrathecally and systemically in MS.     

髓鞘少突胶质细胞糖蛋白抗体在多发性硬化中的意义

目的探讨髓鞘少突胶质细胞糖蛋白(MOG)抗体与多发性硬化(MS)临床表现及复发缓解型MS(RRMS)复发的关系。方法采用酶联免疫吸附法(ELISA)对60例MS、23例其他炎性神经疾病(OIND)、29例非炎性神经疾病(NIND)以及50例神经系统正常的对照(NC)患者血清及脑脊液(CSF)MOG抗体进行检测。结果MS患者CSFMOG抗体阳性率为28.3%(17/60),明显高于NC组[2%(1/50)]和NIND组[0%(0/29)],但与OIND组[21.7%(5/23)]比较差异无统计学意义。各组血清MOG抗体均为阴性。抗体阳性率急性活动期为31.8%(14/44),与稳定期[18.75%(3/16)]比较差异无统计学意义。CSFMOG抗体阳性的RRMS患者复发时间早于阴性患者,且其第1、2年复发率均高于阴性患者。结论在部分MS患者中枢神经系统内存在异常的MOG特异性B细胞免疫应答,且CSFMOG抗体对RRMS的复发有一定预测作用。     

Intrathecal synthesis of soluble HLA-G and HLA-I molecules are reciprocally associated to clinical and MRI activity in patients with multiple sclerosis

The aim of this study was to provide further insight into the effective contribution of classical soluble HLA-A, B and C class Ia (sHLA-I) and non-classical soluble HLA-G class Ib (sHLA-G) molecules in immune dysregulation occurring in multiple sclerosis (MS). We evaluated by enzyme-linked immunosorbent assay (ELISA) technique intrathecal synthesis and cerebrospinal fluid (CSF) and serum levels of sHLA-I and sHLA-G in 69 relapsing-remitting (RR), 21 secondary progressive (SP) and 13 primary progressive (PP) MS patients stratified according to clinical and magnetic resonance imaging (MRI) evidence of disease activity. We also tested, as neurological controls, 91 patients with other inflammatory neurological disorders (OIND) and 92 with non-inflammatory neurological disorders (NIND). Eighty-two healthy volunteers served as further controls for sHLA-I and sHLA-G determinations. An intrathecal production of sHLA-I and sHLA-G detected by specific indexes was significantly more frequent in MS patients than in controls (P<0.01). An intrathecal synthesis of sHLA-I was prevalent in clinically (P<0.02) and MRI active (P<0.001) MS, whereas a CSF-restricted release of sHLA-G predominated in clinically (P<0.01) and MRI stable (P<0.001) MS. sHLA-I levels were low in the serum of clinically active (P<0.001) and high in the CSF of MRI active (P<0.01) MS. Conversely, sHLA-G concentrations were decreased in the serum of clinically stable MS (P<0.01) and increased in the CSF of MRI inactive MS (P<0.001). The trends towards a negative correlation observed between CSF and serum concentrations and intrathecal synthesis of sHLA-I and sHLA-G in patients without evidence of clinical and MRI activity confirmed that intrathecal production and fluctuations in CSF and serum concentrations of sHLA-I and sHLA-G were reciprocal in MS. Our results suggest that, in MS, a balance between classical sHLA-I and non-classical sHLA-G products modulating both MRI and clinical disease activity in opposite directions may exist.     

Interleukin-6 and oligoclonal IgG synthesis in children with acute disseminated encephalomyelitis

Interleukin-6 (IL-6) has a number of roles including recruitment of T lymphocytes and differentiation of B lymphocytes into IgG-secreting plasma cells. Furthermore, IL-6 is a neuropoietic cytokine with effects on neuronal differentiation, function and survival. We studied IL-6 concentrations in children with acute disseminated encephalomyelitis (ADEM; n = 14), and compared the values with those obtained from control patients with other inflammatory (OIND; n = 13) and non-inflammatory (NIND; n = 10) neurological disorders. Patients with ADEM had a significantly increased CSF IL-6 concentration compared with both OIND and NIND groups ( P < 0.01). Serum IL-6 was also increased in the ADEM group compared with the OIND group ( P < 0.05). CSF: serum IL-6 ratios were significantly increased in the ADEM group compared with the NIND group ( P < 0.05), suggesting an intrathecal production of IL-6 rather than its passive transfer across the blood-brain barrier alone. In ADEM, there was a significant correlation between an increased CSF IL-6 and an identical pattern of oligoclonal IgG synthesis in both serum and CSF ( P < 0.05). These results would suggest a role for IL-6 in the pathology of ADEM, and a possible direct link between an increased IL-6 and a proliferation of B lymphocytes with consequent IgG production.     

Secondary lymphoid organ chemokines are elevated in the cerebrospinal fluid during central nervous system inflammation

Secondary lymphoid organ chemokines have been implicated in chronic inflammation. Their expression in the central nervous system (CNS) has not been studied. Here, levels of secondary lymphoid organ chemokines CCL19 (Exodus-3, MIP-3beta), CCL21 (Exodus-2, 6Ckine, SLC) and CXCL12 (SDF-1alpha) were analysed by ELISA in cerebrospinal fluid (CSF) and plasma from patients with multiple sclerosis (MS); acute optic neuritis (ON) with oligoclonal IgG in the CSF (i.e., first bout of MS); acute ON without oligoclonal IgG (non-MS-type ON); other inflammatory neurological diseases (OIND); and non-inflammatory neurological diseases (NIND). NIND CSF contained CCL19 and CXCL12, while CCL21 was not detected. Intrathecal production of CCL19 and CCL21 was elevated in MS, MS-type ON, and OIND, but not in non-MS-type ON. In MS, CSF levels of CCL19 weakly correlated with CSF cell counts. Intrathecal production of CXCL12 was elevated only in OIND. The role of elevated CCL19 and CCL21 in MS could be retention of mature dendritic cells (DC) in the CNS, recruitment of nai;ve T cells and activated B cells, as well as de novo formation of secondary lymphoid structures in MS plaques.     

Chlamydia pneumoniae in multiple sclerosis: humoral immune responses in serum and cerebrospinal fluid and correlation with disease activity marker

Humoral immune responses to Chlamydia pneumoniae (C. pneumoniae) were studied in paired sera and cerebrospinal fluid (CSF) of patients with definite multiple sclerosis (MS) and other inflammatory and non-inflammatory neurological diseases. Seropositivity was not significantly different between these groups. However, C. pneumoniae-specific IgG titers were significantly higher in CSF of MS than in controls. Sixteen out of 52 seropositive MS patients (30.8%) showed intrathecal synthesis of C. pneumoniae-specific IgG but only one of 43 seropositive controls (2.3%). In MS, this was strongly associated with intrathecal synthesis of polyclonal IgG in 13/16 patients. However, these elevated C. pneumoniae antibody titers in CSF did not significantly correlate with disease duration, disease course, clinical or MRI disease activity, disability or presence of oligoclonal IgG in MS.     

Biological markers in cerebrospinal fluid for axonal impairment in multiple sclerosis: acetylcholinesterase activity cannot be considered a useful biomarker

An impairment of the cholinergic system activity has been demonstrated in multiple sclerosis (MS). The correlation between the cholinergic system and the cognitive dysfunction in MS has led to studies on the use of acetylcholinesterase inhibitors (AChEI). The acetylcholinesterase (AChE), essential enzyme for the regulation of turnover of acetylcholine, can be considered the most important biochemical indicator of cholinergic signaling in the nervous system. Besides its catalytic properties, AChE has a crucial role in the regulation of the immune function. Based on the role of the AChe in the regulation of cholinergic signaling in the nervous system, the aim of the present study is to evaluate the activity of AChE in different pathological conditions: MS, other inflammatory neurological disorders (OIND) and non-inflammatory neurological disorders (NIND). We measured AChE activity in CSF samples obtained from 34 relapsing–remitting MS patients and, as controls, 40 patients with other inflammatory neurological disorders (OIND) and 40 subjects with other non-inflammatory neurological disorders (NIND). Fluorimetric detection of the AChE in MS patients and in the controls showed no statistically significant differences: 1.507 ± 0.403 nmol/ml/min in MS patients, 1.484 ± 0.496 nmol/ml/min in OIND and 1.305 ± 0.504 nmol/ml/min in NIND. Similar results were obtained in another recent study, using a different method. Further studies must be conducted on a larger number of patients, with different degrees of cognitive impairment. However, AChE measured in CSF can probably not be considered a useful biomarker for the assessment of the functional alterations of cholinergic system in pathological conditions.     

Antibodies against myelin oligodendrocyte glycoprotein in the cerebrospinal fluid of multiple sclerosis patients

Antibodies against myelin oligodendrocyte glycoprotein (MOG) mediate demyelination in experimental autoimmune encephalomyelitis (EAE) in different animal species and are implicated in the immunopathogenesis of multiple sclerosis (MS). In order to evaluate the anti-MOG response, we have analyzed the cerebrospinal fluids (CSFs) from 44 MS patients and 51 controls, 11 with other inflammatory neurological disorders (OIND) and 40 with non-inflammatory neurological disorders (NIND). The frequency of anti-MOG antibodies positive patients in the MS group (30%) was significantly higher compared to the NIND (8%, p=0.02), but not compared to the OIND group (55%, p=0.228). Interestingly, all six patients with neurosarcoidosis had MOG-specific antibodies in their CSF. Frequency of anti-MOG antibodies was similar in patients with clinically active and stable MS (32% and 26%, respectively; p=0.921). However, in clinically active MS patients, antibody titers were higher in comparison with patients with stable disease, although the difference did not reach the level of statistical significance (p=0.06). These results further support the potential role of anti-MOG antibodies in the immunopathology of MS in the subset of patients with this disease. Furthermore, our findings suggest for the first time that anti-MOG antibodies could be an accessory diagnostic tool in neurosarcoidosis.     

Differential release of beta-chemokines in serum and CSF of patients with relapsing-remitting multiple sclerosis

OBJECTIVE: beta-chemokines were recently demonstrated in active MS-lesions. We tested whether MCP-1 and RANTES can also be detected in CSF and serum of patients with MS and whether release is associated with inflammatory disease activity. MATERIALS AND METHODS: CSF and serum from 34 patients with newly diagnosed relapsing-remitting MS (RR-MS), 17 patients with viral meningitis (VM) and 19 patients with non-inflammatory neurological diseases (NIND) were investigated by ELISA. RR-MS patients underwent lumbar puncture and Gd-enhanced MRI examinations within 2 days. RESULTS: MCP-1 was strong intrathecally released in all patients. Compared to NIND CSF-levels were increased in VM (P<0.001) and were decreased in RR-MS (P<0.05). RANTES was only detected in serum in all patients. Levels were higher in VM and RR-MS compared to NIND (P<0.05). A total of 14/34 RR-MS patients exhibited active Gd-enhancing lesions on MRI. They had lower MCP-1 levels in CSF (P<0.001) and serum (P<0.05) and higher serum levels of RANTES (P<0.05) as compared to patients without active lesions. CONCLUSIONS: MCP-1 and RANTES are differentially released during acute attacks of RR-MS, which might reflect different immunregulatory roles of these beta-chemokines in RR-MS.     

Chlamydia pneumoniae infection associated with enhanced MRI spinal lesions in multiple sclerosis

Cerebrospinal fluid (CSF) from 66 patients with multiple sclerosis (MS) and 25 patients with other neurological diseases (OND) were examined for the infection of Chlamydia pneumoniae by culture, polymerase chain reaction (PCR) assay, and determination of antibodies to C. pneumoniae. PCR was positive not only in 9 of 28 (32%) patients with MS but also in 2 patents with inflammatory disorders in 15 (13%) OND controls (p = 0.18). Viable C. pneumoniae was isolated from one patient with MS and one with paraneoplastic encephalomyelitis. C. pneumoniae could be detected only in cell-containing CSF. In MS, enhanced spinal magnetic resonance imaging (MRI) lesions were detected in all of four PCR-positive patents but none of five PCR-negative patients, and the difference was significant (p = 0.0079). However, no correlation was found between enhanced brain MRI lesions and CSF C. pneumoniae DNA. Elevated titers of anti-C. pneumoniae IgG were detected in CSF in 13 of 66 (20%) patients with MS and 1 of 25 (4%) OND controls (p = 0.064). CNS C. pneumoniae infection is not uncommon in MS as well as in other inflammatory disorders of the nervous system. The association of active spinal lesions with Chlamydia in CSF collected by lumber puncture suggests the detection of a recent infection. On the other hand, the lack of association of active MS brain lesions with CSF Chlamydia and the presence of PCR-positive patents who are clinically stable and have no enhancing MRI lesions imply the existence of a chronic infectious process.     

Reduced cortisol levels in cerebrospinal fluid and differential distribution of 11β-hydroxysteroid dehydrogenases in multiple sclerosis: Implications for lesion pathogenesis

Relapses during multiple sclerosis (MS) are treated by administration of exogenous corticosteroids. However, little is known about the bioavailability of endogenous steroids in the central nervous system (CNS) of MS patients. We thus determined cortisol and dehydroepiandrosterone (DHEA) levels in serum and cerebrospinal fluid (CSF) samples from 34 MS patients, 28 patients with non-inflammatory neurological diseases (NIND) and 16 patients with other inflammatory neurological diseases (OIND). This revealed that MS patients – in sharp contrast to patients with OIND – show normal cortisol concentrations in serum and lowered cortisol levels in the CSF during acute relapses. This local cortisol deficit may relate to poor local activation of cortisone via 11β-hydroxysteroid dehydrogenase type 1 (11bHSD1) or to inactivation via 11bHSD2. Accordingly, 11bHSD2 was found to be expressed within active plaques, whereas 11bHSD1 was predominantly detected in surrounding “foamy” macrophages. Our study thus provides new insights into the impaired endogenous CNS cortisol regulation in MS patients and its possible relation to MS lesion pathogenesis. Moreover, an observed upregulation of 11bHSD1 in myelin-loaded macrophages in vitro suggests an intriguing hypothesis for the self-limiting nature of MS lesion development. Finally, our findings provide an attractive explanation for the effectivity of high- vs. low-dose exogenous corticosteroids in the therapy of acute relapses.     

Molecular detection of Parachlamydia-like organisms in cerebrospinal fluid of patients with multiple sclerosis

The presence of Chlamydia-like organism DNA was investigated by polymerase chain reaction (PCR) in cerebrospinal fluid (CSF) samples from 27 patients previously found positive for Chlamydia pneumoniae DNA: 12 with multiple sclerosis (MS), grouped according to clinical and magnetic resonance imaging (MRI) evidence of disease activity, 8 with other inflammatory neurological disorders and 7 with non-inflammatory neurological disorders. PCR evidence of Chlamydia-like organisms in CSF was observed only in two relapsing-remitting MS patients with clinical and MRI disease activity. These findings suggest a possible association between C. pneumoniae and Chlamydia-like organism brain infections as a cofactor in MS development.     

Chlamydia pneumoniae in the cerebrospinal fluid of patients with multiple sclerosis and neurological controls.

Chlamydia pneumoniae infection is a common event in neurological patients and recovery of C. pneumoniae DNA in the cerebrospinal fluids (CSF) of multiple sclerosis (MS) patients could represent an epiphenomenon. We assessed the relevance of C. pneumoniae infection in 62 CSF samples from 32 MS patients and 30 neurological controls by means of PCR, immunofluorescence microscopy, enzyme-linked fluorescence and antibody detection. Multiple sclerosis (9.3%) and neurological controls (13.3) had similar percentage of anti-C. pneumoniae antibodies. However, C. pneumoniae DNA was only detectable in MS patients' CSF (9.3%). Our data support the hypothesis that C. pneumoniae persistence in some MS patients may be the result of an impaired clearance within the central nervous system.     

IL-15 is elevated in serum and cerebrospinal fluid of patients with multiple sclerosis

Interleukin-15 (IL-15) is a novel proinflammatory cytokine having similar biological activities to IL-2 which is implicated in the pathogenesis of multiple sclerosis. It is produced by activated blood monocytes, macrophages and glial cells. There is little information about the involvement of IL-15 in the development of multiple sclerosis (MS). The objective of our study was to measure IL-15 serum and cerebrospinal fluid (CSF) levels in MS patients and to correlate serum and CSF IL-15 concentrations with clinical parameters of the disease. CSF IL-15/Serum IL-15 ratio (c/s IL-15 ratio) was introduced to assess the origin of elevated IL-15 levels. MATERIALS AND METHODS: We measured serum and CSF IL-15 levels in 52 patients with MS and 36 age and gender matched patients with inflammatory (IND) and non-inflammatory neurological diseases (NIND) studied as control groups. IL-15 levels were correlated with clinical parameters as duration, disability, MRI activity and clinical subtypes of the disease. RESULTS: MS patients were found to have significantly higher serum IL-15 levels compared with IND (p=0.00016) and NIND patients (p=0.00045). Elevated levels of IL-15 were also found in CSF samples from MS patients compared with patients with IND (p=0.00034) and NIND (p=0.0003). Among MS subgroups there were no statistically different IL-15 serum and CSF concentrations. No significant correlation of serum and CSF IL-15 concentrations with MRI activity, disability assessed by EDSS score and duration of the disease were also found. C/S IL-15 ratio was found lower in MS patients compared with IND (p=0.01) and not significantly different compared with NIND patients (p=0.14) suggesting that systemic activation might be the source of high CSF IL-15 levels in MS patients. CONCLUSIONS: Our findings suggest a possible role of IL-15 in the immunopathogenetic mechanisms of MS.