Peripheral neuropathy associated with monoclonal IgM antibody to glycolipids with a terminal glucuronyl-3-sulfate epitope

Concurrent acute sensorimotor axonal neuropathy and disseminated encephalitis associated with Chlamydia pneumoniae in an adult patient with anti-MOG and anti-sulfatide antibodies: a case report

Acute disseminated encephalomyelitis and Guillain-Barré syndrome refer to post-infectious or post-vaccination inflammatory demyelinating disorders of central and peripheral nervous system, respectively. We report the case of a 60-year-old male patient presenting with irritability, gait difficulty, asymmetric quadriparesis (mostly in his left extremities), distal sensory loss for pain and temperature in left limbs, and reduced tendon reflexes in his upper limbs and absent in his lower limbs, following an upper respiratory tract infection, 3 weeks earlier. Brain magnetic resonance imaging revealed abnormal T2 signal and peripherally enhancing lesions in hemispheres, brainstem, and cerebellum. Nerve conduction studies were compatible with acute motor and sensory axonal neuropathy. Serology revealed positive IgM and IgG antibodies for Chlamydia pneumoniae, and he also tested positive for myelin oligodendrocyte glycoprotein (MOG) and sulfatide antibodies. Treatment with intravenous immunoglobulin and methylprednisolone led to clinical and radiological recovery within weeks. Even though several cases of combined central and peripheral demyelination have been reported before, it is the first case report with seropositive anti-sulfatide and anti-MOG acute sensorimotor axonal neuropathy and disseminated encephalitis associated with C. pneumoniae.

Myelin glycosphingolipid immunoreactivity and CSF levels in multiple sclerosis

OBJECTIVES

Patients with multiple sclerosis were reported to harbour antibodies not only against proteins and glycoproteins but also against glycolipids, including sulfatide and galactosylceramide (GalCer), the two major glycosphingolipids of myelin. However, previous results were inconsistent concerning glycosphingolipid levels, antibody type, dominance of serum or Cerebrospinal fluid compartments and relationship to the multiple sclerosis (MS) course.

RESULTS

We hereby report that the cerebrospinal fluid levels of sulfatide were increased in patients with MS (n = 46) compared with controls (n = 50, P < 0.001). In addition, patients had higher serum IgM anti-glycosphingolipid titres than controls (P = 0.03 for sulfatide, <0.001 for GalCer), while the anti-glycosphingolipid IgM antibodies in the cerebrospinal fluid were essentially normal. However, in seven of 46 patients cerebrospinal fluid IgG antibodies against GalCer (P = 0.004) could be detected, which was not found in any of the control individuals, and this finding might mirror the occurrence of more specific B-cell clones behind the blood-brain barrier.

CONCLUSIONS

The IgM immunoreactivity in serum did not show any relationship to the type of course or severity of MS, arguing against a phenomenon secondary to myelin damage. Thus, the IgM antibody findings are compatible with an early antigen challenge or autoimmunity associated with natural antibodies.

The conformational behaviour of the C-glycosyl analogue of sulfatide studied by NMR in SDS micelles

The conformational behaviour of sulfatide and its C-glycosyl analogue has been studied by using a combination of J and NOE data assisted by molecular mechanics calculations. There is a major exoanomeric conformation around the phi angle of both molecules with two or three conformers contributing to the equilibrium around psi. The MM3* calculations only provide a qualitative description of the actual population distribution. Despite this geometrical similarity, the quantitative analysis of the NOE intensities at a variety of mixing times indicates that the motion around the pseudoglycosidic linkages of the C-glycosyl analogue is faster than that for the natural compound.

Fine specificity of antibodies against phospholipids and beta-2-glycoprotein I in monoclonal gammopathy associated neuropathies

Phospholipids are abundantly represented within the nervous system. Aim of our study was to evaluate the presence and fine specificity of anti phospholipid antibodies (aPLAb) among patients with monoclonal gammopathy associated neuropathy. Thirty nine percent of these patients had high titers of aPLAb, mostly associated with low levels of anti beta2 glycoprotein I, which suggests different antibody specificity compared to patients with anti phospholipid syndrome. Further 6/48 patients with dysimmune neuropathy without monoclonal gammopathy had positive aPLAb titers. APLAb strongly cross-reacted with sulfatide. These findings suggest an adjuntive role of aPLAb on nerve damage and may help to better understand the nerve binding properties of anti-sulfatide antibodies.

Antiglycolipid antibodies in Guillain-Barré syndrome and related diseases: Review of clinical features and antibody specificities

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy that usually develops following a respiratory or intestinal infection. Although the pathogenic mechanisms of GBS have not been fully established, both humoral and cell-mediated immune factors have been shown to contribute to the disease process. Several antiglycosphingolipid (anti-GSL) antibodies have been found in the sera of patients with GBS or related diseases. Measurements of these antibody titers are very important in the diagnosis of GBS and in evaluating the effectiveness of treatments in clinical trials. The most common treatment strategies for these disorders involve plasmapheresis and the use of steroids for reducing anti-GSL antibody titers to ameliorate patients' clinical symptoms. Administration of intravenous immunoglobulin may also be beneficial in the treatment of neuropathies by suppressing the immune-mediated processes that are directed against antigenic targets in myelin and axons. In certain demyelinating neuropathies, the destruction or malfunctioning of the blood-nerve barrier, which results in the leakage of circulating antibodies into the peripheral nerve parenchyma, has been considered to be an initial step in development of the disease process. In addition, anti-GSL antibodies, such as anti-GM1, may cause nerve dysfunction and injury by interfering with the ion channel function at the nodes of Ranvier, where carbohydrate epitopes of glycoconjugates are located. These malfunctions thus contribute to the pathogenic mechanisms of certain demyelinating neuropathies.

Antibodies to neuron-specific antigens in children with autism: possible cross-reaction with encephalitogenic proteins from milk, Chlamydia pneumoniae and Streptococcus group A

We measured autoantibodies against nine different neuron-specific antigens and three cross-reactive peptides in the sera of autistic subjects and healthy controls by means of enzyme-linked immunosorbent assay (ELISA) testing. The antigens were myelin basic protein (MBP), myelin-associated glycoprotein (MAG), ganglioside (GM1), sulfatide (SULF), chondroitin sulfate (CONSO4), myelin oligodendrocyte glycoprotein (MOG), alpha,beta-crystallin (alpha,beta-CRYS), neurofilament proteins (NAFP), tubulin and three cross-reactive peptides, Chlamydia pneumoniae (CPP), streptococcal M protein (STM6P) and milk butyrophilin (BTN). Autistic children showed the highest levels of IgG, IgM and IgA antibodies against all neurologic antigens as well as the three cross-reactive peptides. These antibodies are specific because immune absorption demonstrated that only neuron-specific antigens or their cross-reactive epitopes could significantly reduce antibody levels. These antibodies may have been synthesized as a result of an alteration in the blood-brain barrier. This barrier promotes access of preexisting T-cells and central nervous system antigens to immunocompetent cells, which may start a vicious cycle. These results suggest a mechanism by which bacterial infections and milk antigens may modulate autoimmune responses in autism.

Function and molecular modeling of the interaction between human interleukin 6 and its HNK-1 oligosaccharide ligands

Interleukin 6 (IL-6) is endowed with a lectin activity for oligosaccharide ligands possessing the HNK-1 epitope (3-sulfated glucuronic acid) found on some mammalian glycoprotein N-glycans (Cebo, C., Dambrouck, T., Maes, E., Laden, C., Strecker, G., Michalski, J. C., and Zanetta, J. P. (2001) J. Biol. Chem. 276, 5685-5691). Using high affinity oligosaccharide ligands, it is demonstrated that this lectin activity is responsible for the early dephosphorylation of tyrosine residues found on specific proteins induced by interleukin 6 in human resting lymphocytes. The gp130 glycoprotein, the signal-transducing molecule of the IL-6 pathway, is itself a molecule possessing the HNK-1 epitope. This indicates that IL-6 is a bi-functional molecule able to extracellularly associate its alpha-receptor with the gp130 surface complex. Computational modeling indicates that the lower energy conformers of the high affinity ligands of IL-6 have a common structure. Docking experiments of these conformers suggest that the carbohydrate recognition domain of IL-6 is localized in the domain previously identified as site 3 of IL-6 (Somers, W., Stahl, M., and Seehra, J. S. (1997) EMBO J. 16, 989-997), already known to be involved in interactions with gp130.

Glycosphingolipid antibodies in serum in patients with sciatica

STUDY DESIGN

Serum antibody titers against 10 different glycosphingolipids were investigated by enzyme-linked immunosorbent assay in three groups of patients: patients with acute sciatica (Group IA, radicular pain for 32 +/- 36 days, n = 68), a subgroup of these patients 4 years later (Group IB, n = 23), and patients undergoing lumbar discectomy because of disc herniation (Group II, n = 37).

OBJECTIVES

To investigate the immunologic response in sciatica patients by analyzing circulating autoantibodies against glycosphingolipids, molecules highly expressed in cells from the nervous system, and the possible correlation of such antibodies to clinical and imaging findings as well as to subjective symptoms.

SUMMARY OF BACKGROUND DATA

The titers of glycosphingolipid antibodies are elevated in neurologic diseases with autoimmune stimulation such as Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy.

METHODS

Antiglycosphingolipid antibodies were assayed by a microtiter enzyme-linked immunosorbent assay method. Antibody titers were related to a healthy population by a method that judges all positive results (positive result = patient sera/pooled blood donor serum >2, at titer 1/400) as indicating a pathologic condition.

RESULTS

Increased levels of circulating antibodies against one or more glycosphingolipids were detected in 71% of patients with acute sciatica, in 61% of sciatica patients at a 4-year follow-up visit (eight antigens analyzed) and in 54% in patients undergoing discectomy. These frequencies were somewhat higher than, and in the last group similar to, those reported for generalized nervous system disorders with autoimmune involvement. In the acute sciatica patients, positive neurologic findings were associated with increased levels of two of the examined antibodies: 3'LM1 (immunoglobulin M and/or immunoglobulin G), P = 0.023, and GD1a (immunoglobulin M), P = 0.017.

CONCLUSION

The presence of glycosphingolipid antibodies in patients with sciatica and disc herniation suggests an activation of the immune system and thus a process possibly involved in the pathophysiology of sciatica. The autoimmune response was not limited to antibodies against one specific glycosphingolipid target; rather, an overall increase in autoantibodies against nervous system-associated glycosphingolipids was observed. These results encourage further studies of the pathophysiologic and clinical relevance of autoimmune responses in patients with sciatica and disc herniation.

Myelin protein P0-specific IgM producing monoclonal B cell lines were established from polyneuropathy patients with monoclonal gammopathy of undetermined significance (MGUS)

Monoclonal expansion of B cells and plasma cells, producing antibodies against 'self' molecules, can be found not only in different autoimmune diseases, such as peripheral neuropathy (PN), but also in malignancies, such as Waldenström's macroglobulinaemia and B-type of chronic lymphocytic leukaemia (B-CLL), as well as in precancerous conditions including monoclonal gammopathy of undetermined significance (MGUS). About 50% of patients with PN-MGUS have serum antibodies against peripheral nerve myelin, but the specific role of these antibodies remains uncertain. The aims of the study were to establish, and characterize, myelin-specific B cell clones from peripheral blood of patients with PN-MGUS, by selection of cells bearing specific membrane Ig-receptors for myelin protein P0, using beads coated with P0. P0-coated magnetic beads were used for selection of cells, which subsequently were transformed by Epstein--Barr virus. The specificity of secreted antibodies was tested by ELISA. Two of the clones producing anti-P0 antibodies were selected and expanded. The magnetic selection procedure was repeated and new clones established. The cells were CD5+ positive, although the expression declined in vitro over time. The anti-P0 antibodies were of IgM-lambda type. The antibodies belonged to the VH3 gene family with presence of somatic mutations. The IgM reacted with P0 and myelin-associated glycoprotein (MAG), and showed no evidence for polyreactivity, in contrast to other IgM CD5+ clones included in the study as controls. The expanded clones expressed CD80 and HLA-DR, which is compatible with properties of antigen-presenting cells. The immunomagnetic selection technique was successfully used for isolation of antimyelin protein P0-specific clones. The cell lines may provide useful tools in studies of monoclonal gammopathies, leukaemia, and autoimmune diseases, including aspects of antigen-presentation by these cells followed by T cell activation.

High-titre IgM anti-sulfatide antibodies in individuals with IgM paraproteinaemia and associated peripheral neuropathy

The common association between monoclonal gammopathy and peripheral neuropathy was studied in seven patients with demyelinating polyneuropathy and IgM paraproteinaemia. Plasma samples from these individuals were thoroughly tested for antiperipheral nerve myelin (PNM) antibodies and then screened for glycoprotein and glycolipid reactivity by western immunoblotting and thin-layer chromatography (TLC) immunostaining. Three of the seven samples showed strong IgM anti-PNM and antisulfatide (GalS) antibody reactivity. Two of these three plasma samples showed extraordinarily high antisulfatide IgM antibody titres, ranging from 1 x 104 to 1 x 106 arbitrary units/L. These same samples also showed intense myelin staining of sciatic nerve sections (paraffin and cryostat) and teased nerve fibres. No axonal immunoreactivity was observed. These results suggest that high titre IgM antisulfatide antibodies may play a pathogenetic role in the immune demyelination associated with IgM paraproteinaemia.

Recovery of severe sciatica

STUDY DESIGN

A prospective study of patients with acute severe sciatica.

OBJECTIVES

To 1) describe the characteristics of patients with acute severe sciatica and the agreement among different diagnostic tests, 2) describe overall recovery during 1 year in terms of perceived disability, and pain, and 3) explore acute-phase predictors of failure to recover at 1 year.

SUMMARY OF BACKGROUND DATA

The development of imaging techniques has been very impressive during recent decades. However, different authors have highlighted the prevalence of abnormal images among asymptomatic subjects. These findings increase the difficulty of interpreting the results from the diagnostic techniques used with each individual patient. Furthermore, other clinical and biopsychosocial variables need to be explored for their associations with recovery or failure to recover. This study aimed to explore those associations.

METHODS

Consecutive patients admitted to the hospital for conservative management of severe acute sciatica were eligible for inclusion in the study. Patients were evaluated at admission, discharge, and 3, 6, and 12 months. All the visits included a standardized clinical examination and the completion of questionnaires that included items on demographics, pain, perceived disability, and quality of life. Imaging and blood samples were collected at the first visit, and an electromyogram was taken for sciatica lasting at least 3 weeks.

RESULTS

The study included 82 consecutive patients (66% men) with a mean age of 43 +/- 10.3 years. The mean intensity of pain, on a visual analog scale of 0 to 100 (VAS) at Visit 1, was 73. The straight leg raising test was positive in 78% of the patients, with a mean value of 59 degrees +/- 18 degrees. The contralateral straight leg raising test was positive in 20% of the patients. Imaging was positive for disc herniation in 74% and electromyogram was positive in 62% of cases. These two diagnostic tests showed a good to excellent total agreement (58-87%) with the straight leg raising tests and the presence of radiating pain below the knee. The recovery of clinical symptoms and signs was observed mainly within the first 3 months. However, clinical recovery and perceived recovery was not complete in most cases.

CONCLUSIONS

In most cases, there was good to excellent agreement among the different diagnostic tests. None of the tests was predictive of recovery. The presence of blood antibodies against 3'LM1 (IgM + IgG) and GD1a (IgM) was significantly associated (P < 0.023) with neurologic symptoms and signs. However, the meaning of these antibodies remains unclear. Only a minority of the patients (29%) had fully recovered after 12 months. Within the 1-year follow-up, one third of the patients had surgery.

The role of antiglycolipid antibodies in neurological disorders

Glycolipids have been shown to be antigens for circulating antibodies in autoimmune processes affecting the nervous system like neuropathy associated with IgM paraproteinemia, Guillain Barré syndrome (GBS), multifocal neuropathy, and variants thereof. The antibody titers, the Ig-classes, and the antibody specificity vary between studies and disease groups. The immunogens are in general unknown. However, GBS is often associated with an infection with Campylobacter jejuni, which expresses a lipopolysaccharide structure similar to the carbohydrate epitopes in sialic acid containing glycolipids and gangliosides and thus a potential primary antigen for antiganglioside antibodies. The antiglycolipid specificity will most likely reflect the primary antigen carbohydrate epitopes, which also determine the target cell or tissue structure and the pathology. These factors might add to the inconsistent results obtained and that have led to the question: Are antiglycolipid antibodies of any clinical significance?

Electrospray ionization tandem mass spectrometric analysis of sulfatide. Determination of fragmentation patterns and characterization of molecular species expressed in brain and in pancreatic islets

The sphingolipid sulfatide is a component of myelin and some non-neuronal cells. Antibodies to sulfatide occur in some patients with autoimmune neuropathies and in patients with insulin-dependent diabetes mellitus (IDDM) caused by immunologic destruction of insulin-secreting pancreatic islet beta-cells. Distinct sulfatide molecular species may differ in immunogenicity, and facile means to identify sulfatide species in islets and other tissues obtainable in only small amounts could be useful. Electrospray ionization mass spectrometry (ESI/MS) permits structural determination of small quantities of phospholipids and is applied here to sulfatide analysis. We find that sulfatide standards are readily analyzed by negative ion ESI/MS, and tandem mass spectra of individual species exhibit some ions common to all species and other ions that reflect distinct fatty acid substituents in different sulfatide molecules. A signature ion cluster resulting from cleavage directed by the alpha-hydroxy group of sulfatide species with a hydroxylated fatty acid substituent identifies such species. Sulfatide profiles in tissue lipid extracts can be obtained by ESI/MS/MS scanning for common sulfatide ions and for ions reflecting fatty acid substituents. Islets are demonstrated to contain sulfatide and to exhibit a profile of species different from that of brain.

Sulphatide-binding properties are shared by serum amyloid P component and a polyreactive germ-line IgM autoantibody, the TH3 idiotype

Serum amyloid P component (SAP) concentration was elevated in sera from leprosy patients, significantly so above endemic controls in lepromatous cases. In the sera of lepromatous leprosy (LL) patients who experienced an erythema nodosum leprosum (ENL) episode the SAP fell at the onset of ENL and remained low throughout, in two of three cases. Changes in SAP concentration parallel anti-sulphatide IgM concentrations. TH3, a monoclonal IgM germ-line antibody derived from a LL patient, and SAP share similar binding patterns. In this study we demonstrate binding to heparin and sulphatide. Moreover, SAP inhibited the binding of TH3 to sulphatide, as well as anti-sulphatide IgM found in a range of sera, and anti-sulphatide IgG in the only sera sample in which it was found. The observation that anti-TH3 idiotype monoclonal and polyclonal anti-SAP antibodies both inhibited the binding of TH3 and IgM in sera (but not IgG) to sulphatide without binding to sulphatide themselves further demonstrated similar binding specificities. The observations of similarity in binding reinforce ideas that SAP may function as a primitive opsonin, but the clear ability to inhibit binding of autoantibodies suggests that SAP may play a role in ameliorating tissue and particularly nerve damage in leprosy patients.

Glycosphingolipids as potential diagnostic markers and/or antigens in neurological disorders

Glycosphingolipids are most abundant in the nervous system within which are developmental, regional, structural and cellular differences regarding their composition. The are shedded to the cerebrospinal fluid and thus potential markers for pathogenic alterations in the brain, such as developmental abnormalities, demyelination, gliosis, neuronal cell destruction. The glycosphingolipids have also been found to be antigens in autoimmune processes involving the nervous system, in particular in peripheral neuropathies like Guillain Barré syndrome, multifocal motor neuropathy etc. The immune response might have been triggered by infectious agents with an antigen epitope which mimic the glycosphingolipid or by a primary nerve tissue damage leading to release of glycosphingolipids. There is a series of support for a clinical significance of cerebrospinal fluid glycosphingolipid determinations and the presence of anti-glycosphingolipid antibodies but this has to be further explored. This paper is a mini review of the state of the art and discuss methodological aspects and improvements that might help to explore the relevance of glycosphingolipids in neurological disorders.

Polyneuropathies associated with high titre antisulphatide antibodies: characteristics of patients with and without serum monoclonal proteins

OBJECTIVES

Previous studies of small numbers of patients have shown that antisulphatide autoantibodies are associated with polyneuropathies having a prominent sensory component. However, clinical and electrodiagnostic features are variable. The range of clinical and electrodiagnostic findings in 19 patients with polyneuropathies and high titre (> 4500) serum IgM antisulphatide antibodies is described, together with testing for serum monoclonal (M) proteins.

METHODS

About 20000 serum samples that were referred to the clinical laboratory from 1990 to the end of 1994 were screened by enzyme linked immunosorbent assay (ELISA) for specific high titre antisulphatide antibodies. The clinical and electrodiagnostic data in 23 patients with positive results were reviewed. IgM binding to peripheral nerve structures was also evaluated in these patients.

RESULTS

Nineteen patients had predominantly distal, symmetric pansensory loss. Patients with IgM antisulphatide antibodies and no serum M protein usually had clinical syndromes that included: (1) neuropathic pain or dysaesthesiae, (2) no functionally significant weakness, and (3) an axonal neuropathy on electrodiagnostic testing. On immunocytochemical studies serum IgM from the patients without M proteins usually (nine of 10; 90%) bound to peripheral nerve axons, but never to myelin. Patients with antisulphatide antibodies and a serum M protein, usually IgM, were more likely than patients without a serum M protein, to have syndromes with: (1) no pain or dysaesthesiae, (2) motor abnormalities, and (3) a demyelinating polyneuropathy by electrodiagnostic criteria. In immunocytochemical studies serum IgM most often bound to either peripheral nerve myelin or endoneurial structures.

CONCLUSION

Patients with polyneuropathy and high titre serum IgM antisulphatide antibodies can be classified into subgroups according to the presence or absence of a serum M protein. Patients without an M protein are more likely to have pure sensory syndromes, pain, an axonal neuropathy, and serum IgM binding to axons. Patients with a serum M protein commonly had syndromes with prominent motor involvement, no pain, and a demyelinating neuropathy.

CD5 expression on B cells may be an activation marker for secretion of anti-myelin antibodies in patients with polyneuropathy associated with monoclonal gammopathy

B cells expressing the CD5 marker belong to a subpopulation with potential autoreactive properties. Increased proportions of CD5+ B cells have been reported in autoimmune diseases. In patients with monoclonal gammopathy and demyelinating polyneuropathy, the M-component often consists of autoantibodies reacting with myelin components. We therefore investigated if CD5+ B cells were involved in the production of anti-myelin antibodies. There was no difference of mean value of CD5+ B cells between patients and controls. However, the proportion of CD5+ B cells was significantly correlated with the amount of anti-myelin antibodies. In seven patients, CD5+ B cells were enriched using an immunomagnetic technique. The number of CD5+ and CD5- B cells secreting anti-myelin antibodies was determined by ELISPOT. In two patients with high levels of antibodies, antibody-secreting cells were mainly, but not exclusively, CD5+ B cells. In five patients with low levels of antibodies, most cells secreting anti-myelin antibodies were CD5-. We conclude that CD5 expressed on B cells may be an activation marker, reflecting B cells producing high amounts of anti-myelin antibodies in patients with polyneuropathy associated with monoclonal gammopathy.

Autoantibodies to cerebroside sulphate (sulphatide) in leprosy

Sera from 40 leprosy patients were screened for autoantibodies to cerebroside sulphate (sulphatide). Anti-sulphatide IgM in groups of patients with lepromatous (LL) and borderline (BL + BB + BT), but not with tuberculoid (TT) disease, were significantly elevated above the levels found in endemic control subjects. Eight-six percent (18 out of 21; mean 1.59 OD units) of LL, 33% (four out of 12; mean 1.08 OD units) of borderline and 13% (one out of eight; mean 0.69 OD units) of tuberculoid patients had anti-sulphatide IgM in their sera above a cut-off value of 2 s.d. above the mean value (0.66 OD units) for control sera. Elevated anti-sulphatide IgG was detected in only one patient's serum, an individual with LL disease. The level of anti-sulphatide IgM was strongly correlated to expression of the TH3 idiotype, an idiotype previously defined by a human MoAb that bound Mycobacterium leprae phenolic glycolipid, Klebsiella capsular polysaccharide, polynucleotides and human tissues. The purified, TH3 MoAb was found in this study to bind sulphatide, but not cholesterol-3-sulphate or cerebroside. It is suggested that anti-sulphatide IgM is elevated in leprosy, in relation to the bacterial load. Anti-sulphatide IgM fell at the onset of erythema nodosum leprosum (ENL) reaction, consistent with the deposition of serum antibodies, and thus may play a part in pathology during periods of inflammation, particularly in multibacillary patients.

Abnormalities in T-lymphocyte populations in blood from patients with demyelinating polyneuropathy associated with monoclonal gammopathy

Patients with monoclonal gammopathy secrete monoclonal antibodies (M-component), that in some patients are associated with polyneuropathy. The M-component has been shown to react with peripheral nerve myelin in some of these patients. However, it is not known whether the M-component secreting B-cells are autonomous or subject to regulation by T-cells or if other cellular abnormalities may occur. In order to define circulating lymphocyte subpopulations, flow cytometry was done on blood samples from patients with monoclonal gammopathy and demyelinating polyneuropathy (n = 13) and patients with monoclonal gammopathy without polyneuropathy (n = 11), and were compared to healthy controls. Significantly increased proportions of primed T-helper (CD4+) cells, i.e. those expressing helper/inducer function (CD29+ CD4+), providing help for antibody secretion, as well as decreased proportions of naive, unprimed suppressor/inducer (CD45RA+ CD4+) T-helper cells were found in patients with M-component associated polyneuropathy. Within the T-cytotoxic/suppressor population (CD8+) we found an increased proportion of killer/effector (S6F1+ CD8+) cells and a decreased proportion of suppressor/effector (S6F1- CD8+) cells in patients with monoclonal gammopathy and polyneuropathy. Similar findings were found in monoclonal gammopathy patients without polyneuropathy, although the deviations in general were less pronounced and did not reach statistical significance compared to the controls. The proportion of natural killer (NK) cells (CD56+) was markedly decreased in all patients with monoclonal gammopathy. In the whole group of patients with monoclonal gammopathy, we found clear proportions of interleukin-2 receptor (CD25+) expressing lymphocytes, indicating the presence of activated T-cells. No clear correlation between abberations in T-cell subtypes and clinical severity of the demyelinating polyneuropathy or titres of anti-PNM antibodies was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Sulphatide and sulphatide antibodies in insulin-dependent diabetes mellitus

Insulin-dependent diabetes mellitus (IDDM) is associated with neurological disorders. Sulph I, a monoclonal antibody to sulphatide (a neural epitope), stained secretory granules in alpha and beta cells of rat islets of Langerhans, but not exocrine tissue. Sera from 88% of 57 newly diagnosed IDDM patients was anti-sulphatide positive, and 76% were positive 6 months later. All 135 healthy controls were negative. Sulphatide antibody may be an IDDM marker.