Takahiko Saida

Temporal changes and geographical differences in multiple sclerosis phenotypes in Japanese: nationwide survey results over 30 years.

Background There are two distinct phenotypes of multiple sclerosis (MS) in Asians, manifesting as optic-spinal (OSMS) and conventional (CMS) forms. In Japan, four nationwide surveys of MS have been conducted. The first three were in 1972, 1982, and 1989, and we performed the fourth in 2004. Results The recent survey showed six main findings as follows: (1) a four-fold increase in the estimated number of clinically definite patients with MS in 2003 (9900; crude MS prevalence, 7.7/100,000) compared with 1972; (2) a shift in the peak age at onset from early 30s in 1989 to early 20s in 2003; (3) a successive proportional decrease in optic-spinal involvement in clinically definite patients with MS; (4) a significant north–south gradient for the CMS/OSMS ratio; (5) after subdivision of the mainland (30–45° North) into northern and southern parts at 37°N, northern-born northern residents (northern patients) showed a significantly higher CMS/OSMS ratio and higher frequency of brain lesions fulfilling the Barkhof criteria (Barkhof brain lesions) than southern-born southern residents (southern patients); (6) among northern patients, the absolute numbers of patients with CMS and those with Barkhof brain lesions rapidly increased with advancing birth year. Conclusions These findings suggest that MS phenotypes are drastically altered by environmental factors, such as latitude and “Westernization.”

Anti-aquaporin 4 antibody in selected Japanese multiple sclerosis patients with long spinal cord lesions:

Multiple sclerosis (MS) in Asian populations is often characterized by the selective involvement of the optic nerve (ON) and spinal cord (SP) (OSMS) in contrast to classic MS (CMS), where frequent lesions are observed in the cerebrum, cerebellum or brainstem. In Western countries, inflammatory demyelinating disease preferentially involving the ON and SP is called neuromyelitis optica (NMO). Recently, Lennon et al. discovered that NMO-IgG, shown to bind to aquaporin 4 (AQP4), could be a specific marker of NMO and also of Japanese OSMS whose clinical features were identical to NMO having long spinal cord lesions extending over three vertebral segments (LCL). To examine this antibody in larger populations of Japanese OSMS patients in order to know its epidemiological and clinical spectra, we established an immunohistochemical detection system for the anti-AQP4 antibody (AQP4-Ab) using the AQP4-transfected human embryonic kidney cell line (HEK-293) and confirmed AQP4-Ab positivity together with the immunohistochemical staining pattern of NMO-IgG in approximately 60% of Japanese OSMS patients with LCL. Patients with OSMS without LCL and those with CMS were negative for this antibody. Our results accorded with those of Lennon et al. suggest that Japanese OSMS with LCL may have an underlying pathogenesis in common with NMO. Multiple Sclerosis 2007; 13: 850—855. http://msj.sagepub.com

Antibodies to gangliosides and galactocerebroside in patients with Guillain–Barré syndrome with preceding Campylobacter jejuni and other identical infections

The relationship between preceding infections and antibodies to glycolipids was investigated in 205 Japanese patients with Guillain-Barré syndrome (GBS). Serological evidence of recent Campylobacter jejuni (C. jejuni) infection was found in 45% of the patients, compared with 1% in healthy controls. In contrast, recent infection of cytomegalovirus (CMV), Mycoplasma pneumoniae (M. pneumoniae) and Epstein-Barr virus (EBV) was detected in only 5%, 2% and none of the patients, respectively. C. jejuni-associated GBS was more frequent in early spring than in other seasons. All stool specimens positive for C. jejuni isolation were obtained within 10 days after the onset of GBS symptoms. Of 13 C. jejuni isolates from GBS patients, 10 (77%) belonged to Penner serotype 19 (heat-stable, HS-19). Elevated titers of anti-GM1 antibody were found in 8 (80%) of 10 GBS patients whose C. jejuni isolates belonged to HS-19 and in none of those infected with non-HS-19 C. jejuni (P = 0.04), and in 49% of 92 patients with C. jejuni infection and 25% of patients without infection of C. jejuni, CMV, EBV, or M. pneumoniae (P = 0.0007). The frequencies of elevated antibody titers to GD1a, GD1b and GQ1b were also significantly higher in GBS patients associated with C. jejuni than those not associated with C. jejuni, CMV, EBV, and M. pneumoniae. GBS in Japan seems to be associated more frequently with C. jejuni and less frequently with CMV than in Europe and North America.

Post-infectious encephalitis with anti-galactocerebroside antibody subsequent to Mycoplasma pneumoniae infection

Galactocerebroside (Gc) is a major component of myelin in both the peripheral and central nervous systems. Although it is regarded as an important glycolipid hapten of myelin in rabbit experimental allergic neuritis (EAN), its role in human demyelinating diseases is not known. We studied three post-infectious encephalitis (PIE) patients related to Mycoplasma pneumoniae infection. All three of three patients with encephalitis and M. pneumoniae infection were positive for Gc antibodies (100%), while 25% of 32 M. pneumoniae-infected patients without neurological disease were positive, and 3.8% of 52 healthy controls. This indicates anti-Gc antibody is induced by M. pneumoniae infection. One of the PIE patients, who had extraordinary high titer antibody to Gc, showed an extensive, diffuse white matter demyelination and poor recovery. Since circulating anti-Gc antibody induces central nervous system demyelination in animals with elevated antibody titers and disruption of the blood-brain barrier, anti-Gc antibody may have an important function in the increased demyelination in PIE patients after M. pneumoniae infection.

Long term culture of bovine oligodendroglia isolated with a percoll gradient

Oligodendroglia were isolated from calf central nervous system (CNS) white matter by trypsinization in phosphate buffered saline and separation by centrifugation through Percoll. Using antisera to phenotypic markers and double labelling experiments we were able to identify essentially all cells in the cultures. The cells obtained were: (1) viable; (2) had intact plasma membranes and well preserved organelles, ribosomes and mitochondria; and (3) were greater than or equal to 95% oligodendroglia 16-20 h after isolation as determined by ability to bind antigalactocerebroside antibodies (anti-GalC). Oligodendroglia could be cultured for several weeks to months. Oligodendroglia established and maintained processes which bound anti-GalC. Myelin basic protein could be demonstrated in the cytoplasm of 40-60% of oligodendroglia cell bodies but not in the processes.

Anti-GalNAc-GD1a antibody–associated Guillain-Barré syndrome with a predominantly distal weakness without cranial nerve impairment and sensory disturbance

The serum antibodies to N‐acetylgalactosaminyl GD1a (GalNAc‐GD1a) and other gangliosides as well as to Campylobacter jejuni were determined in 147 patients with Guillain‐Barré syndrome (GBS). We found a distinctive clinical pattern in patients with anti‐GalNAc‐GD1a antibodies compared with those without the antibodies, that is, lack of cranial nerve involvement (87% versus 38%), distal‐dominant weakness (80% versus 25%), and no sensory disturbance (73% versus 22%). The frequency of distal‐dominant weakness was significantly higher in patients with both C jejuni infection and anti‐GalNAc‐GD1a positivity (100%) than in C jejuni–negative/anti‐GalNAc‐GD1a–positive (25%), C jejuni–positive/anti‐GalNAc‐GD1a–negative (32%) and C jejuni–negative/anti‐GalNAc‐GD1a–negative patients (20%). Lack of cranial nerve involvement and sensory disturbance were found in most C jejuni–positive/anti‐GalNAc‐GD1a–positive and C jejuni–negative/anti‐GalNAc‐GD1a–positive patients, but not in C jejuni–positive/anti‐GalNAc‐GD1a–negative and C jejuni–negative/anti‐GalNAc‐GD1a–negative patients. Although the anti‐GM1–positive/anti‐GalNAc‐GD1a–negative patients mostly (75%) lacked cranial nerve involvement, distal‐dominant weakness (38%) and lack of sensory disturbance (13%) were infrequent. These results may indicate that (1) the combination of C jejuni infection and anti‐GalNAc‐GD1a antibodies, but not anti‐GalNAc‐GD1a, anti‐GM1, or C jejuni infection alone, is associated with a predominantly distal weakness, (2) the presence of anti‐GalNAc‐GD1a, rather than C jejuni infection or anti‐GM1 antibody, is associated with a lack of sensory disturbance, (3) both anti‐GalNAc‐GD1a and anti‐GM1 antibodies are independently associated with a lack of cranial nerve impairment. Ann Neurol 1999;45:758–768

Clinical study of FK506 in patients with myasthenia gravis

To investigate the usefulness of low‐dose FK506 for the treatment of myasthenia gravis (MG), we treated 19 patients with generalized MG in a 16‐week open clinical trial of FK506 (3–5 mg/day). At the end of the trial, total MG scores (range: 0–27 points) improved by 3 points or more in 7 of 19 patients (37%), and activities of daily living (ADL) scores (range: 0–6 points) also improved by 1 point or more in 8 of 19 patients (42%). Nine of 19 patients (47%) showed improvement in either MG or ADL scores. Significant reduction of anti‐acetylcholine receptor antibody titers and interleukin 2 production were observed at the end of this study. Minor but commonly observed side effects were an increase in neutrophil count and a decrease in lymphocyte count. No serious adverse events such as renal toxicity or diabetes mellitus were observed during the 16‐week treatment period. FK506 could safely serve as an adjunct to steroid therapy for MG at low dosage. Muscle Nerve 28: 570–574 2003

Demyelination produced by experimental allergic neuritis serum and anti-galactocerebroside antiserum in CNS cultures

SummaryCultures of mouse cerebellum were exposed to sera from rabbits with experimental allergic neuritis induced by whole peripheral nerve immunization (WN-EAN) and to rabbit anti-galactocerebroside (GC) antisera, and were studied by electron microscopy. Both antisera produced almost identical demyelinative patterns. These consisted of large intramyelinic splittings, “smudged” changes of myelin, degeneration of oligodendrocytes, and phagocytosis of myelin by astrocytes, changes similar to those described after application of whole spinal cord-induced experimental allergic encephalomyelitis (WM-EAE) sera. In addition, patterns which have been considered more characteristic of in vivo demyelinative lesions have been found, such as vesicular disruption of myelin lamellae and peeling off and phagocytosis of myelin by phagocytic mononuclear cells with electron dense cytoplasm. The morphologic similarities between demyelinative patterns in central nervous system (CNS) cultures induced by anti-GC antiserum and WN-EAN serum and WM-EAE serum, and the fact that elevated antibody titers to GC are found in sera from rabbits with WN-EAN and WM-EAE (Saida, et al., 1977), support the concept that anti-GC antibody is the major factor in the production of CNS demyclination in vitro by sera from rabbits with WN-EAN and WM-EAE.

HLA and T-cell receptor gene polymorphisms in Guillain-Barré syndrome

Objective: We examined a possible involvement of genetic factors influencing the development of Guillain-Barré syndrome (GBS). Methods: We studied T-cell receptor (TCR), alpha-chain constant (AC), and beta-chain variable (BV) gene polymorphisms using microsatellite markers and serologic HLA class I antigens, HLA-DRB1, and HLA-DQB1 alleles in 81 Japanese patients with GBS and 87 controls. Results: There were no significant differences in these genetic markers between GBS patients and controls. Subgrouping of GBS patients according to recent Campylobacter jejuni infection, the presence of anti-GM1 antibody in the sera, or their combinations also failed to reveal significant associations with these genetic markers. There was, however, a tendency for an increased frequency of HLA-DRB1*0803 in the C. jejuni + GM1 + GBS group, when compared with controls. Conclusions: The data suggest that the roles of TCRAC, T-cell receptor beta-chain variable (TCRBV), HLA class I or class II in the development of GBS are not critical, and further research is necessary to clarify other genes encoded within the HLA region for genetic susceptibility to GBS.

A randomized, controlled trial of fingolimod (FTY720) in Japanese patients with multiple sclerosis

Background: Fingolimod (FTY720) has previously shown clinical efficacy in phase II/III studies of predominantly Caucasian populations with multiple sclerosis (MS). Objectives: To report six-month efficacy and safety outcomes in Japanese patients with relapsing MS treated with fingolimod. Methods: In this double-blind, parallel-group, phase II study, 171 Japanese patients with relapsing MS were randomized to receive once-daily fingolimod 0.5 mg or 1.25 mg, or matching placebo for six months. The primary and secondary endpoints were the percentages of patients free from gadolinium (Gd)-enhanced lesions at months 3 and 6, and relapses over six months, respectively; safety outcomes were also assessed. Results: 147 patients completed the study. Higher proportions of patients were free from Gd-enhanced lesions at months 3 and 6 with fingolimod (0.5 mg: 70%, p = 0.004; 1.25 mg: 86%, p < 0.001) than with placebo (40%). Odds ratios for the proportions of relapse-free patients over six months favoured fingolimod versus placebo but were not significant. Adverse events related to fingolimod included transient bradycardia and atrioventricular block at treatment initiation, and elevated liver enzyme levels. Conclusions: This study demonstrated the clinical efficacy of fingolimod for the first time in Japanese patients with MS, consistent with the established effects of fingolimod in Caucasian patients.