Th1/Th2 cytokine balance and nitric oxide in cerebrospinal fluid and serum from patients with multiple sclerosis

Tumor necrosis factor (TNF-alpha) and IL-10 are key regulators of the T helper (Th)1/Th2 balance, which is critically skewed in many pathological conditions including immune-mediated inflammatory diseases of central nervous system (CNS) such as multiple sclerosis (MS). Nitric oxide (NO) has been reported to have dual effects on CNS pathology, and to play an important role in MS. We performed a cross-sectional study in 17 randomly selected patients during MS flare-up, and compared levels of TNF-alpha, IL-10 and NO in serum and cerebrospinal fluid (CSF) with the serum values of these mediators in two different control groups, healthy subjects and HIV-infected untreated patients. Serum and CSF values of TNF-alpha, IL-10 and NO were higher in MS patients than in the serum of healthy controls. Two MS patients showed increased levels of NO in CSF, with inversion of the NO(SERUM)/NO(CSF) quotient, which is clearly indicative of an intrathecal production of NO. No correlation among the values of both cytokines and NO, and the laboratory parameters analysed in MS patients (IgG index, presence of IgG oligoclonal bands and albumin quotient) was found. The high levels of TNF-alpha and IL-10 (both in serum and CSF) accompanying an MS attack suggest a simultaneous expression of Th1 and Th2 cytokines as opposed to sequential expression of Th1 followed by Th2 as described in the models of experimental autoimmune encephalomyelitis (EAE). Globally, our results support the inherent heterogeneity of the disease.     

Restricted heterogeneity of antibody to gp120 and p24 in AIDS

Neurologic complications and cerebrospinal fluid (CSF) abnormalities are common in AIDS. We found that a substantial number of AIDS patients with neurologic involvement had oligoclonal IgG bands in CSF and sera by IEF. Using an IEF-Ag overlay technique, anti-gp120 antibody activity was demonstrated more frequently than anti-p24 antibody activity. These antibody activities exhibited restricted heterogeneity of their IEF pattern; this restriction may contribute to the relatively low titers of neutralizing antibody found in AIDS sera. None of the CSF and serum oligoclonal bands showed anti-HIV antibody activity, suggesting that they are directed against opportunistic agents or result from immunodysregulation.     

Cerebrospinal-fluid profile in neuroborreliosis and its diagnostic significance

Selected cerebrospinal-fluid (CSF) parameters (intrathecal synthesis ofBorrelia-specific antibodies, oligoclonal IgG bands, CSF-to-serum quotient of albumin as a marker of blood-CSF barrier function and cytology) and typical CSF profile in neuroborreliosis were evaluated with the aim of elucidating possible clinical and laboratory similarities of neuroborreliosis (NB) and other neurological diseases (OND). From the cohort of 58 patients (38 diagnosed for NB, 20 with OND) NB patients had positiveBorrelia-specific IgG antibodies in 97 % and positiveBorrelia-specific IgM antibodies in 55 %; oligoclonal IgG bands were detected in 55 %. The blood-CSF barrier was impaired in 89 %, positive cytology was detected in 97 % of the NB patients. Evaluation of specific intrathecal synthesis improves CSF diagnosis of NB, therefore, a combined CSF analysis has to be considered along with the clinical picture and medical history when formulating the diagnosis of NB.     

A Sensitive Method for Characterization of Oligoclonal Immunoglobulins in Unconcentrated Cerebrospinal Fluid

Abstract: Although isoelectric focusing has been used to demonstrate the presence of oligoclonal IgG in the CSF, the technique has not allowed detection of oligoclonal IgG in unconcentrated CSF. A new technique is reported, by which unconcentrated CSF is separated by isoelectric focusing, and the IgG bands are then detected by radioimmunofixation. Samples as small as 20 μl may be used.     

Chlamydia pneumoniae and multiple sclerosis: no significant association

The cause of multiple sclerosis (MS) is unknown. Despite indications from epidemiological and identical-twin studies that MS is infectious, no virus or other infectious agent has been tightly linked to disease. The isolation of Chlamydia pneumoniae from the cerebrospinal fluid (CSF) of MS patients and the detection of both Chlamydia-specific DNA and antibody in MS CSF have been reported. Other analyses of brain and CSF have shown no significant difference in C. pneumoniae-specific DNA or antibody between MS and control subjects. Recent work has revealed intrathecal production of C. pneumoniae-specific IgG in only 24% of MS patients compared with 5% of control patients. More importantly, the major CSF oligoclonal bands from MS patients did not react to C. pneumoniae.     

Specificity of oligoclonal IgG bands against myelin proteins in chronic relapsing EAE in guinea pigs

We showed previously by using imprint electroimmunofixation that the oligoclonal IgG in sera and CSF from chronic relapsing EAE in guinea pigs were specific to spinal cord and Mycobacterium tuberculosis. We now show that most oligoclonal IgG bands are directed predominantly against isolated myelin basic protein (MBP). Activity to the latter could be removed from sera or CSF by absorption with MBP but not with histone or lysozyme. The oligoclonal IgG reacted weakly with isolated proteolipid apoprotein, and lacked reactivity to myelin-associated glycoprotein. When the oligoclonal IgG activity to myelin proteins was removed from the sera by absorption with a preparation of delipidated myelin before imprint electroimmunofixation, a few bands in some sera still reacted with whole spinal cord homogenate. These results indicate that, in some sera, a part of the oligoclonal IgG was directed against non-myelin proteins or lipids. In contrast to chronic relapsing EAE, CSF oligoclonal IgG from patients with multiple sclerosis showed no reactivity against human brain homogenate, whole myelin, delipidated myelin, and MBP in imprint electroimmunofixation.     

Immunoglobulins and complement in demyelination induced in mice by Theiler's virus

Intracerebral inoculation of Theiler's murine encephalomyelitis virus (TMEV) produces chronic demyelination and persistent infection in the central nervous system (CNS) of susceptible SJL mice. This series of experiments examined the contribution of humoral immunity and C to myelin destruction. As in multiple sclerosis, mice persistently infected with TMEV had elevated levels of IgG and oligoclonal bands in the cerebrospinal fluid (CSF). Immunoblot studies revealed that even in animals exhibiting profound demyelination, IgG in the serum and CSF was directed primarily at virus antigen rather than at normal myelin components. Inflammatory cells positive for Ig were distributed mainly around blood vessels, but occasionally they infiltrated the spinal cord parenchyma. Rare examples of myelin sheaths positive for IgG were found by immunoelectron microscopy in spinal cord sections from infected mice; the third component of complement (C3) was commonly found in the walls of CNS blood vessels but not on myelin. Neither serum nor CSF IgG from infected mice bound to myelin sheaths or other CNS components in sections of normal syngeneic spinal cord. There were significantly more demyelinating lesions in infected mice depleted of C components with cobra venom factor. These data do not support a humoral autoimmune basis for the CNS demyelination that occurs in association with persistent TMEV infection. However, the humoral immune response directed at TMEV antigens may either limit virus spread or promote virus persistence.     

Comparative analysis of the CD19+ and CD138+ cell antibody repertoires in the cerebrospinal fluid of patients with multiple sclerosis

Increased amounts of intrathecally synthesized IgG and oligoclonal bands have long been recognized as a hallmark of multiple sclerosis (MS). B cells and plasma cells are components of the inflammatory infiltrates in both active and chronic MS lesions, and increased numbers of these cells are present in MS cerebrospinal fluid (CSF). Single-cell RT-PCR was used to analyze both the CD19+ B cell and CD138+ plasma cell populations in CSF of two patients with clinically definite MS and of one MS patient whose CSF was obtained after a clinically isolated syndrome, but before the second episode. Sequence analysis of amplified IgG V region sequences identified the rearranged germline segments, extent of somatic mutation, and clonal relationships within and between the two cell populations in the three MS patients. Expanded B cell and plasma cell clones were detected in each MS CSF and in all three patients the CD138+ IgG repertoire was more restricted. However, little if any significant sequence overlap was observed between the CD19+ and CD138+ repertoires of each donor. Detection of plasma cell clones by single-cell PCR will facilitate the in vitro production of recombinant Abs useful in identifying disease-relevant Ags.     

VH4 gene segments dominate the intrathecal humoral immune response in multiple sclerosis

A characteristic feature of the CNS inflammatory response in multiple sclerosis (MS) is the intrathecal synthesis of IgG and the presence of oligoclonal bands. A strong correlation between CD138(+) plasma blast numbers in MS cerebrospinal fluid (CeSF) and intrathecal IgG synthesis suggests that these cells are the major Ab-secreting cell type in MS CeSF. Sequencing of V regions from CD138(+) cells in MS CeSF has revealed somatically mutated and expanded IgG clonotypes consistent with an Ag-targeted response. In the present study, single-cell RT-PCR analysis of CD138(+) cells from 11 MS patients representing differing clinical courses and stages of disease identified expansion of CD138(+) cells with functionally rearranged V(H)4 gene segments as an overriding feature of MS CeSF repertoires. V(H)4 dominance was attributed to the preferential selection of specific V(H)4 genes, particularly gene segment V(H)4-39, which displayed a significant enrichment in CeSF compared with MS peripheral blood B cells. A modest increase in V(H)4 prevalence among MS peripheral blood IgG memory cells was also noted, suggesting that factors shaping the CD138 repertoire in CeSF might also influence the peripheral IgG memory cell pool. These results indicate a highly restricted B cell response in MS. Identifying the targets of CeSF plasma cells may yield insights into disease pathogenesis.     

Cloning the antibody response in humans with inflammatory central nervous system disease: analysis of the expressed IgG repertoire in subacute sclerosing panencephalitis brain reveals disease-relevant antibodies that recognize specific measles virus antigens.

The presence of increased IgG in the brains of humans with infectious and inflammatory CNS diseases of unknown etiology such as multiple sclerosis may be a clue to the cause of disease. For example, the intrathecally synthesized oligoclonal bands (OGBs) in diseases such as subacute sclerosing panencephalitis (SSPE) or cryptococcal meningitis have been shown to represent Ab directed against the causative agents, measles virus (MV) or Cryptococcus neoformans, respectively. Using SSPE as a model system, we have developed a PCR-based strategy to analyze the repertoire of IgG V region sequences expressed in SSPE brain. We observed abnormal expression of germline V segments, overrepresentation of particular sequences that correspond to the oligoclonal bands, and substantial somatic mutation of most clones from the germline, which, taken together, constitute features of Ag-driven selection in the IgG response. Using the most abundant or most highly mutated gamma H chain and kappa or lambda L chain sequences in various combinations, we constructed functional Abs in IgG mammalian expression vectors. Three Abs specifically stained MV-infected cells. One Ab also stained cells transfected with the MV nucleoprotein, and a second Ab stained cells transfected with the MV-fusion protein. This technique demonstrates that functional Abs produced from putative disease-relevant IgG sequences can be used to recognize their corresponding Ags.     

Genetic and Infectious Profiles Influence Cerebrospinal Fluid IgG Abnormality in Japanese Multiple Sclerosis Patients

Background

Abnormal intrathecal synthesis of IgG, reflected by cerebrospinal fluid (CSF) oligoclonal IgG bands (OBs) and increased IgG index, is much less frequently observed in Japanese multiple sclerosis (MS) cohorts compared with Western cohorts. We aimed to clarify whether genetic and common infectious backgrounds influence CSF IgG abnormality in Japanese MS patients.

Methodology

We analyzed HLA-DRB1 alleles, and IgG antibodies against Chlamydia pneumoniae, Helicobacter pylori, Epstein-Barr virus nuclear antigen (EBNA), and varicella zoster virus (VZV) in 94 patients with MS and 367 unrelated healthy controls (HCs). We defined CSF IgG abnormality as the presence of CSF OBs and/or increased IgG index (>0.658).

Principal Findings

CSF IgG abnormality was found in 59 of 94 (62.8%) MS patients. CSF IgG abnormality-positive patients had a significantly higher frequency of brain MRI lesions meeting the Barkhof criteria compared with abnormality-negative patients. Compared with HCs, CSF IgG abnormality-positive MS patients showed a significantly higher frequency of DRB1*1501, whereas CSF IgG abnormality-negative patients had a significantly higher frequency of DRB1*0405. CSF IgG abnormality-positive MS patients had a significantly higher frequency of anti-C. pneumoniae IgG antibodies compared with CSF IgG abnormality-negative MS patients, although there was no difference in the frequency of anti-C. pneumoniae IgG antibodies between HCs and total MS patients. Compared with HCs, anti-H. pylori IgG antibodies were detected significantly less frequently in the total MS patients, especially in CSF IgG abnormality-negative MS patients. The frequencies of antibodies against EBNA and VZV did not differ significantly among the groups.

Conclusions

CSF IgG abnormality is associated with Western MS-like brain MRI features. DRB1*1501 and C. pneumoniae infection confer CSF IgG abnormality, while DRB1*0405 and H. pylori infection are positively and negatively associated with CSF IgG abnormality-negative MS, respectively, suggesting that genetic and environmental factors differentially contribute to MS susceptibility according to the CSF IgG abnormality status.     

Oligoclonal IgG in rabbits with experimental allergic encephalomyelitis: Non-reactivity of the bands with sensitizing neural antigens

Oligoclonal IgG bands have recently been reported to occur in cerebrospinal fluid (CSF) and serum of rabbits with experimental allergic encephalomyelitis (EAE). To examine the specificity of these bands, a) individual bands eluted from rabbit CSF and sera were tested by radioimmunoassay (RIA) for anti-MBP activity and b) rabbit sera were absorbed with the neuroantigens used for sensitization. RIA of eluates from sequential agar gel slices of the entire IgG region of serum or CSF from MBP sensitized rabbits showed that anti-MBP activity occurred throughout the IgG region and did not localize to specific band-containing fractions. Furthermore, there was no change in banding patterns following absorption of EAE rabbit sera with washed brain homogenates, soluble MBP or MBP conjugated to Sepharose beads. Therefore, our results indicate that the oligoclonal IgG response in EAE is not preferentially directed against the sensitizing neuroantigen, and we raise the possibility of nonspecific B cell activation.     

Identification of a unique idiotype in cerebrospinal fluid and serum of a patient with multiple sclerosis

Anti-idiotypic antibodies were prepared in mouse ascites fluid against the CSF-IgG of a patient with multiple sclerosis. After adsorption with pooled human IgG, the ascites fluid antibodies precipitated 20% of labeled autologous CSF IgG. By using a competitive radioimmunoassay, less than one microgram of unlabeled CSF IgG produced 50% inhibition of binding autologous 125I-labeled CSF IgG, whereas 50 micrograms of normal HIgG was not inhibitory. The idiotype could be found in both serum and CSF IgG and persisted over a 5-year period. The absolute concentration of idiotype in the CSF varied somewhat but remained from 4 to 10 times greater than that of the serum. One of 14 heterologous MS CSF was found to contain small amounts of inhibitory protein; eight CSF from patients with other neurologic diseases did not contain the idiotype.     

Multiplexing analysis of the polyspecific intrathecal immune response in multiple sclerosis

Intrathecal synthesis of the antibodies specific to neurotrofic viruses: measles (M), rubella (R), Varicella-Zoster (Z), and/or H. simplex (H), known as "MRZH-reaction" plays important diagnostic role in multiple sclerosis (MS). Whereas the analysis of the oligoclonal IgG bands provides high sensitivity, the MRZH-reaction shows high specificity, and hence these methods complement each other. For the first time we applied multiplexing bead-based technology to simultaneously analyze cerebrospinal fluid (CSF) and serum concentrations of antibodies against these viruses, and to calculate the antibody specific indices (ASI's). The method shows reasonable precision: intra-assay, 2.9-6.7%, and inter-assay, 2.0-3.2%. The results are comparable with these obtained with other methods (ELISAs), including two runs of the certified external quality control schemes. Eighty-one percent of the MS cases (n=27) and none of the sex- and age-matched controls (n=14), except one subject with "borderline" anti-measles ASI of 1.5, showed intrathecal synthesis of IgG against at least one of the viruses discussed. The ratios of the MRZH-positive cases in the MS group were: 12/22 for M, 12/19 for R, 13/26 for Z, and 7/26 for H. We conclude that the multiplexing technology can be applied as a tool to study the intrathecal immune response in the diagnosis of MS.     

Cerebrospinal fluid and serum oligoclonal IgG bands in rabbits with experimental allergic encephalomyelitis

Rabbits sensitized with whole nervous tissue or myelin basic protein (MBP) plus adjuvant and developing experimental allergic encephalomyelitis (EAE) were studied for the presence of oligoclonal immunoglobulin (Ig) bands in spinal fluid and serum. Samples obtained prior to sensitization and at the time of sacrifice were concentrated and subjected to agar gel electrophoresis. Of 11 rabbits receiving whole nervous tissue and developing severe clinical signs of EAE, 7 showed new oligoclonal Ig bands in spinal fluid and in serum obtained 19 days or more after sensitization. With MBP sensitization, 2 of 6 rabbits exhibited new spinal fluid bands, while all 6 rabbits studied demonstrated serum banding. The bands were identified as IgG by immunochemical studies using peroxidase-labeled antisera and byStaph. protein A absorption. The majority of animals showed no banding in presensitization samples. The finding of oligoclonal IgG in EAE reveals yet another immunologic correlation between EAE and the human demyelinating disease, multiple sclerosis.     

Specific activation of B-cell clones within the central nervous system in course of herpes simplex encephalitis

Total and virus-specific immunoglobulin (Ig) G oligoclonal bands were studied in paired serum and cerebrospinal fluid (CSF) of four patients with herpes simplex virus type 1 (HSV-1) encephalitis. We used the isoelectric focusing in agarose gel, a sensitive technique for protein separation, followed by passive transfer of proteins on nitrocellulose paper and specific immunostaining. Oligoclonal bands were observed in serum and CSF of all patients. HSV-1-specific oligoclonal IgG bands were present in the CSF only during a limited period of the disease, having their counterpart in serum during the remaining periods. Our findings contribute to tackle the issue of B-cell activation within central nervous system and peripheral blood compartments in course of HSV-1 encephalitis.     

Antigen discovery in chronic human inflammatory central nervous system disease: panning phage-displayed antigen libraries identifies the targets of central nervous system-derived IgG in subacute sclerosing panencephalitis.

The presence of increased IgG in the brains of humans with infectious and inflammatory CNS diseases of unknown etiology such as multiple sclerosis may be a clue to the cause of disease. For example, the intrathecally synthesized oligoclonal bands in diseases such as subacute sclerosing panencephalitis (SSPE) or cryptococcal meningitis have been shown to represent Ab directed against the causative agents, measles virus (MV), or Cryptococcus neoformans, respectively. Using SSPE as a model system, we developed a strategy to identify the antigenic targets of the intrathecal disease-relevant IgG in chronic human inflammatory and demyelinating diseases of the CNS. Libraries of cDNA Ags were displayed on the surface of T7Select bacteriophage and biopanned on IgG extracted from the brain of an SSPE patient, or on a monospecific recombinant Fab identified from SSPE brain. After three or six rounds of biopanning on either Ab, positive phage-displayed Ags reacting with IgG were enriched to 35-77% of all panned clones. Sequence analysis of the positive clones identified fragments of the nucleocapsid protein of MV, the cause of SSPE. The sensitivity of the system was determined by diluting the positive clones from this SSPE phage-displayed library at a ratio of 10(-6) into another phage-displayed library that did not contain any detectable MV Ags; after six rounds of panning, the positive clones comprised 34% of all phage and were also shown to be MV nucleocapsid specific. This strategy will be useful to identify potentially rare Ags in diseases of unknown cause.     

The role of antibodies in multiple sclerosis

B cells, plasma cells, and antibodies are commonly found in active central nervous system (CNS) lesions in patients with multiple sclerosis (MS). B cells isolated from CNS lesions as well as from the cerebrospinal fluid (CSF) show signs of clonal expansion and hypermutation, suggesting their local activation. Plasma blasts and plasma cells maturating from these B cells were recently identified to contribute to the development of oligoclonal antibodies produced within the CSF, which remain a diagnostic hallmark finding in MS. Within the CNS, antibody deposition is associated with complement activation and demyelination, indicating antigen recognition-associated effector function. While some studies indeed implied a disease-intrinsic and possibly pathogenic role of antibodies directed against components of the myelin sheath, no unequivocal results on a decisive target antigen within the CNS persisted to date. The notion of a pathogenic role for antibodies in MS is nevertheless empirically supported by the clinical benefit of plasma exchange in patients with histologic signs of antibody deposition within the CNS. Further, such evidence derives from the animal model of MS, experimental autoimmune encephalomyelitis (EAE). In transgenic mice endogenously producing myelin-specific antibodies, EAE severity was substantially increased accompanied by enhanced CNS demyelination. Further, genetic engineering in mice adding T cells that recognize the same myelin antigen resulted in spontaneous EAE development, indicating that the coexistence of myelin-specific B cells, T cells, and antibodies was sufficient to trigger CNS autoimmune disease. In conclusion, various pathological, clinical, immunological, and experimental findings collectively indicate a pathogenic role of antibodies in MS, whereas several conceptual challenges, above all uncovering potential target antigens of the antibody response within the CNS, remain to be overcome.     

A new myelin protein, TPPP/p25, reduced in demyelinated lesions is enriched in cerebrospinal fluid of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease with variable extent of remyelination coupled with the differentiation of oligodendrocytes, in which Tubulin Polymerization Promoting Protein/p25 (TPPP/p25) plays a crucial role. Previously we reported that the loss of TPPP/p25-positive oligodendrocytes in demyelinated lesions in the brain of MS patients could be a biomarker for MS [2]. In this work we tested the occurrence of TPPP/p25 in the cerebrospinal fluid (CSF) of MS patients, and by elaborating a sensitive assay for quantification of TPPP/p25 we showed that its level is significantly higher than in the case of non-MS patients. Patients with MS were diagnosed at the Department of Neurology, University of Szeged according to the clinical and laboratory diagnostic criteria of McDonald. In non-MS patients no significant pathological changes were detected on magnetic resonance imaging scans, while in MS patients multiple hyperintense T2 lesions in the white matter were detected. Kurtzke Expanded Disability Status Scale scores as well as IgG level and oligoclonal bands of MS patients were demonstrated. The sensitive assay elaborated in this study is based upon Western blot followed by chemiluminescent detection validated by human recombinant protein. The median TPPP/p25 contents in the CSF were 62.8 and 64.7 μg/L for patients with clinically isolated syndromes and relapsing remitting MS, respectively, while this value for non-MS patients was 27.9 μg/L. The enrichment of TPPP/p25 was independent of age, gender and the time period between lumbar puncture and relapse/shub. These data suggest that the TPPP/p25-based assay could be a powerful diagnostic test for MS patients.     

Chronic meningitis and Lyme disease in Sweden.

We studied 35 patients with chronic meningitis. The neurological abnormalities included aseptic meningitis, cranial neuropathy (mostly facial palsy), motor and sensory peripheral radiculoneuropathy, and myelitis. Neurological symptoms were sometimes preceded by erythema chronicum migrans or an insect bite and were often accompanied by fever, malaise, profound fatigue, and weight loss. The cerebrospinal fluid (CSF) abnormalities consisted of a predominantly mononuclear pleocytosis, an elevated CSF protein (mean 2.3 g/l), intrathecal synthesis of oligoclonal immunoglobulin G, and, in half of the patients, a fall in the CSF/blood glucose ratio. High antibody titers to the Lyme spirochete and the Swedish Ixodes ricinus spirochete were demonstrated by immunofluorescence in 26 of the 35 patients. By imprint immunofixation of electrofocused samples of serum and CSF, intrathecal production of oligoclonal Lyme-spirochete-specific IgG was demonstrated in one patient with chronic meningitis. Four sequential paired samples of serum and CSF from this patient showed local synthesis of spirochete-specific antibodies in CSF. The 35 patients improved or recovered, sometimes dramatically, during a two-week course of intravenous penicillin G.