Immunological faecal occult blood testing: a discriminatory test to identify colorectal cancer in symptomatic patients

INTRODUCTION

Current investigation for patients with colorectal symptoms without overt rectal bleeding is undertaken by colonoscopy or by flexible sigmoidoscopy and barium enema. A large majority of patients do not have colorectal cancer. There exists no instant, objective measure to discriminate patients who are likely to have colorectal cancer and therefore require expedient investigation.

AIM

To evaluate the sensitivity and specificity of immunological faecal occult blood testing (FOBT) in patients with colorectal symptoms without overt rectal bleeding.

METHODS

Consecutive patients referred for urgent colonic investigation, were prospectively studied. A faecal sample was obtained from each one and subjected to immunological FOB which tested either negative or positive. All patients then underwent complete colonic imaging. The correlation between FOBT status and results from colonic imaging was studied.

RESULTS

Of 126 tested, thirty patients (26.8%) were FOBT positive. One hundred and twelve patients underwent complete colonic imaging. In the FOBT positive group colonic imaging identified 17 cases of histologically proven adenocarcinoma, 1 recurrent squamous cell carcinoma of anus, 1 adenomatous polyp, 6 cases of diverticulosis, and no pathology in 5 cases. In the 82 FOBT negative patients, no cancers were found. Overall the Immunological Faecal Occult Blood Test was found to have 100% sensitivity and 86.3% specificity.

CONCLUSION

Immunological faecal occult blood testing is a sensitive and specific test in identifying colorectal cancer and may be useful in identifying those patients who warrant urgent investigation. Routine clinical application may be useful in the allocation of resources.

An investigation of susceptibility loci in benign, aggressive and primary progressive multiple sclerosis in Northern Irish population

OBJECTIVE

To investigate the possibility that susceptibility loci in multiple sclerosis (MS) have a role in determining the disease outcome in Northern Ireland population.

BACKGROUND

The Genetic Analysis of Multiple Sclerosis in Europeans (GAMES) initiative and follow-up refined analysis identified 15 candidate susceptibility loci within the Northern Irish population for MS. We aimed to investigate the 12 most significant markers for their role in disease outcome.

METHODS

Cases with probable or definite MS (Poser criteria) were classified as benign onset (Kurtzke Expanded Disability Status Scale [EDSS]<or=3.0 at 10 years), aggressive (Kurtzke EDSS>or=6.0 by 10 years), or primary progressive MS. All cases were Caucasian of Northern Irish origin. DNA was extracted from venous blood, microsatellite markers were amplified using polymerase chain reaction and typed using fluorescent fragment analysis. Allele frequencies were compared statistically using a chi-squared test with allowance for multiple comparisons (critical P<0.0042); significant markers were further analyzed by CLUMP (critical P<0.0014).

RESULTS

Two microsatellite markers were significant: D3S1278 (Chr 3q13, P<0.001) and tumor necrosis factor (TNF)-alpha (Chr 6p21, P<0.001). A further three markers were significant in our preliminary analysis suggesting a trend toward impact on disease outcome; D4S432 (Chr 4p16, P=0.001), D2S347 (Chr 2q14, P=0.003), and D19S903 (Chr 19p13, P=0.003).

CONCLUSIONS

This is the first study to suggest a role for TNF-alpha in the disease outcome in MS. Larger replication studies need to be performed to assess the role of markers D4S432, D2S347, and D19S903.

Changes in the relative expression pattern of multiple vitellogenin genes in adult male and larval zebrafish exposed to exogenous estrogens

Production of the lipoprotein vitellogenin (Vg) is induced in fish upon exposure to estrogens and is a biomarker of endocrine disruption in fish. In some fish, three types of Vg (VgA, VgB, and VgC) are recognized and transcribed from at least three distinct Vg genes (vtg). We investigated expression of vtg coding for Vg1A/B, Vg2A/B, and VgC in adult male and larval zebrafish exposed to various estrogenic substances. Quantitative PCR was conducted for transcripts of each vtg and a control gene (beta-actin). Male fish were exposed to 17beta-estradiol (E2) and 17alpha-ethinylestradiol, total RNA was extracted from excised liver, and histopathology of liver, trunk kidney, and gonads was conducted. Larval fish were exposed to 10 different estrogenic substances and total RNA was extracted from groups of whole larvae. In adult male fish, the relative fold change varied, but pattern of expression change (i.e., Vg1A/B > Vg2A/B > VgC) was consistent. Larger males exposed to E2 had significantly higher induction of each vtg. In larval zebrafish, the relative fold change in vtg expression varied according to specific estrogenic substance tested, but the pattern of change (i.e., Vg2A/B > Vg1A/B > VgC) was consistent for each substance that induced vtg.

Factors in the rising prevalence of multiple sclerosis in the north-east of Ireland

BACKGROUND

Northern Ireland is recognized as an area of high risk for multiple sclerosis. The original study of Allison and Millar in 1951 found a prevalence of 51/100,000 and mean annual incidence of 2.74/100,000/year. Subsequent studies in 1961, 1986, and 1996 suggested rising prevalence--80, 138, and 168.2/100,000, respectively.

METHODS

In 2004, we surveyed the North-East of Northern Ireland (population 160,446, area 2030 km(2)) using multiple sources of case ascertainment, all satisfying the Poser criteria for definite or probable multiple sclerosis (MS) or the McDonald criteria.

RESULTS

From a provisional list of 469 cases, 370 (123 males, 247 females) were identified. The prevalence was 230.6 per 100,000 (95% CI 207.0-255.4) with significantly higher prevalence in females (300.8/100,000) than males (157.0/100,000). Direct standardization to the 1961 Northern Ireland population reduced the overall prevalence rate to 200.5/100,000 (95% CI 193.2-208.0), in females to 270.2/100,000 (95% CI 258.8-282.4) and in males to 131.1/100,000 (95% CI 122.8-139.9). In 1996, incidence had risen to 9.3/100,000/year (14 cases in population of 151,000) with a higher incidence in females (10.3/100,000/year) than males (8.3/100,000/year).

CONCLUSIONS

Northern Ireland continues to have a rising prevalence of MS. The increase in incidence suggests a true increase in the disease.

Differential expression of erythroid genes in prion disease

We previously reported reduced expression of erythroid-associated factor (ERAF) within haematopoietic tissues of rodent scrapie models, suggesting an unrecognized role for the erythroid lineage in prion disease. In the present study, we compared the expression of a panel of erythroid genes within four murine scrapie models and five virus infection models with parallels to prion disease pathogenesis. We report that differential expression of erythroid genes is not limited to ERAF, and is a common feature of murine scrapie, dependent on host expression of cellular prion protein. In contrast, erythroid gene expression was not altered following virus infection. Whilst these results further implicate cells of the erythroid lineage in the peripheral pathogenesis of prion disease, analysis of blood from BSE-infected cattle and scrapie-infected sheep reveals that the extent of differential expression of erythroid genes within peripheral blood is not sufficient to provide a discriminatory diagnostic test.

Mapping candidate non-MHC susceptibility regions to multiple sclerosis

Understanding the genetic basis of multiple sclerosis (MS) remains a major challenge, despite decades of intensive research. In order to identify candidate non-MHC susceptibility regions to MS, the results of whole genome screens for linkage or association and follow-up studies in 18 different populations were superimposed together in a combined genomic map. Analysis of this map led to the prediction of at least 38 potential susceptibility regions, each showing linkage and/or association in several populations. Among these, 17 regions were the most reproducibly reported in these studies, thus representing top predicted candidates for MS. This non-formal approach to meta-analysis demonstrated the ability to verify results and retrieve lost information in an association study. Assessment of the map in a Northern Irish refined screen (n=415 cases, n=490 controls) revealed association in 15 regions (P<0.05), including 10 promising candidates on chromosomes 1p13, 2p13, 2q14, 3p23, 7q21, 13q14, 15q13, 17p13, 18q21 and 20p12 (P<0.0025). Seven of these regions were previously overlooked in the Northern Irish whole genome association study. Collating results from numerous studies, this draft map represents a tool that should facilitate the analysis of the genetic backgrounds of MS in many populations.

IFNG polymorphisms are associated with gender differences in susceptibility to multiple sclerosis

Interferon-gamma (IFNgamma) treatment is deleterious in multiple sclerosis (MS). MS occurs twice as frequently in women as in men. IFNgamma expression varies by gender. We studied a population-based sample of US MS patients and ethnicity-matched controls and independent Northern Irish and Belgian hospital-based patients and controls for association with MS, stratified by gender, of an intron 1 microsatellite [I1(761)*CAn], a single nucleotide polymorphism 3' of IFNG [3'(325)*G --> A] and three flanking microsatellite markers spanning a 118 kb region around IFNG. Men carriers of the 3'(325)*A allele have increased susceptibility to MS compared to noncarriers in the USA (P=0.044; OR: 2.58, 95% CI: 0.97-8.08) and Northern Ireland (P=0.019; OR: 2.37, 95% CI: 1.10-5.13). There is a nonsignificant trend in the same direction in Belgian men (P=0.299; OR: 1.50, 95% CI: 0.71-3.26). Men carriers of I1(761)*CA13, which is in strong linkage disequilibrium with the 3'(325)*A, have increased susceptibility (P=0.050; OR: 2.22, 95% CI: 0.98-5.40), while men carriers of I1(761)*CA12 have decreased susceptibility (P=0.022; OR: 0.46, 95% CI: 0.23-0.90) to MS in the USA. Similar associations were reported in Sardinia between the I1(761)*CA12 allele and reduced risk of MS in men. Flanking markers were not associated with MS susceptibility. Polymorphisms of IFNG may contribute to differences in susceptibility to MS between men and women.

Influence of CCR5 delta32 polymorphism on multiple sclerosis susceptibility and disease course

The CCR5 chemokine receptor has been implicated in the pathogenesis of multiple sclerosis (MS). We carried out an allelic association study using a deletion polymorphism in the coding region of the CCR5 gene in 331 relapsing-remitting (RR) and secondary progressive (SP) MS patients, 108 primary progressive (PP) MS patients and 230 healthy controls. Of the 331 RR and SPMS patients, 172 were recruited from specialist clinics and 159 from a population survey. Disease severity was assessed clinically using the Expanded Disability Status Scale (EDSS) and used to calculate a progression index for each patient (defined as EDSS divided by duration of disease). No significant difference in distribution of the CCR5 delta32 allele was observed between the 331 RR/SPMS patients and controls, between the 108 PPMS patients and controls or between the PPMS and RR/SPMS groups. Furthermore, no differences in rate of disease progression were detected between carriers and noncarriers of the delta32 allele. In the population-based group of RR/SPMS patients, carriage of the CCR5 delta32 polymorphism was associated with a lower age at disease onset (mean age 26.562 versus 31.065 years, P = 0.003). However, no significant differences in age of onset were present in the PPMS group or in a second RRMS population. These results suggest that the CCR5 delta32 polymorphism is not a major determinant of susceptibility to develop MS in the population under study, and conflict with a previously reported association between CCR5 delta32 carriage and a better prognosis.

Latitudinal variation in the prevalence of multiple sclerosis in Ireland, an effect of genetic diversity

BACKGROUND

Northern Ireland has a high and rising prevalence rate of multiple sclerosis (MS). The most recent survey in 1996 found a rate of 168.7/100 000. Recorded prevalence rates for the south of Ireland, including County Wexford, have been markedly lower and seemed to suggest the existence of a prevalence gradient within the island.

OBJECTIVES

To compare the prevalence of multiple sclerosis in Co. Wexford in the south east of Ireland and Co. Donegal in the north west, and to establish whether a variation in prevalence of MS exists within Ireland.

METHODS

Patients were referred from multiple sources. Review of clinical case records and/or patient examination confirmed the diagnosis.

RESULTS

In Co. Wexford, 126 patients were found to have clinically definite or probable multiple sclerosis with a prevalence rate of 120.7/100 000 (95% confidence intervals (CI) 100.6 to 143.8), which is similar to other areas of similar latitude within the British Isles. In Co. Donegal, 240 people had clinically definite or probable MS with a prevalence rate of 184.6/100 000 (95% CI 162.0 to 209.5). The difference in prevalence rates is statistically significant (Z = 3.94, p = <0.001).

CONCLUSION

There is a latitudinal variation in the prevalence rate of MS between the north and the south of Ireland. The increased prevalence of MS seen in Co. Wexford is likely to represent better case ascertainment and improved diagnostic accuracy rather than an actual increase in prevalence. The north/south variation in prevalence may represent a variation in the genetic predisposition to MS between the background populations of the two counties.

Expression of the bilateral deficit during reflexively evoked contractions

During maximal contractions, the sum of forces exerted by homonymous muscles unilaterally is typically larger than the sum of forces exerted by the same muscles bilaterally. This phenomenon is known as the bilateral deficit (BLD), and it is suggested that this deficit is due to neural inhibition. It remains unclear, however, whether such inhibition is mediated by supraspinal mechanisms or by reflex pathways at the level of spinal cord. To further study the origin of likely neural influences, we tested for the presence of BLD under the condition of reflexive force generation. Force output and integrated electromyogram (iEMG) (quadriceps femoris) were measured in 17 male participants after initiation of the myotatic patellar reflex under unilateral and bilateral conditions. A significant BLD of 9.26 +/- 1.19 (P = 0.004) and 16.76 +/- 4.69% (P = 0.001) was found for force and iEMG, respectively. However, because similar findings were not evident during maximal isometric knee extensions, it is difficult to predict the contribution of a spinal mechanism to the BLD under the condition of maximal voluntary activation.

Primary progressive multiple sclerosis: increasing clarity but many unanswered questions

Heterogeneity in the clinical course of multiple sclerosis (MS) is well recognised and patients following a primary progressive course, 10-15% of the MS population, have a distinct clinical and paraclinical phenotype. This review examines recent advances in our understanding of this subgroup of patients and examines the new criteria to be applied in diagnosis. It also highlights developments in genetic, immunological, magnetic resonance and pathological aspects of the disease, whilst also outlining the results of recent therapeutic trials.

Influence of weight training exercise and modification of hormonal response on skeletal muscle growth

To investigate the influence of carbohydrate (CHO) consumption on the acute hormonal response, and chronic adaptation to weight lifting exercise, two studies were conducted. Following a four-hour fast, seven young men (21.3 +/- 3.5 y) performed (on two occasions) a nine-station weight lifting protocol, completing 3 sets of 10 repetitions at 75% of 1RM (series 1). Randomly assigned, one session included the ingestion of a non-caloric placebo, and the other, a 6% CHO solution. For series 2, two groups of young men (21.3 +/- 1.5 y) participated in 12 weeks of progressive resistance weight training. Training for one group included the ingestion of a non-caloric placebo, and the other, a 6% CHO solution. In series 1, weight lifting exercise with CHO ingestion significantly (p < 0.05) elevated blood glucose and plasma insulin levels above baseline, as well as that occurring with the placebo. This resulted in a significant blunting of the cortisol response (7% with CHO compared to 99% with placebo). These findings indicate that CHO consumption during weight lifting exercise can modify the acute hormonal response to exercise. With series 2, CHO consumption continued to blunt the cortisol response to exercise during the twelve weeks of training. This is in contrast to significantly elevated cortisol levels observed for the placebo control group. Corresponding with the modified response patterns were differences in muscle growth. Weight training exercise with CHO ingestion resulted in significantly greater gains in both type I (19.1%) and type II (22.5%) muscle fibre area than weight training exercise alone. The difference in the cortisol response accounted for 74% of the variance (r = 0.8579, p = 0.006) of change in type I muscle fibre area, and 52.3% of the variance (r = 0.7231, p = 0.043) of change in type II muscle fibre area. These findings suggest that the modification of the cortisol response associated with CHO ingestion can positively impact the skeletal muscle hypertrophic adaptation to weigh training.

Rapid test for the preclinical postmortem diagnosis of BSE in central nervous system tissue

The efficacy of a rapid test for detecting PrP(Sc) in central nervous system tissue was evaluated for the postmortem diagnosis of BSE at different times during the course of the disease. One hundred and six samples of brain, at the level of the medulla oblongata, and spinal cord, derived from the experimental study of the pathogenesis of BSE carried out in Great Britain between 1991 and 1995, were examined. PrP(Sc) was detected in the samples from most of the exposed animals killed 32 months or more after they had been exposed to the agent, and before the onset of clinical signs which were first recorded at 35 months. Comparisons with the results of histology, fibril detection, PrP immunohistochemistry and mouse bioassay indicated that the rapid test is at least as sensitive as these conventional confirmatory diagnostic methods and its result can be obtained more quickly.

A longitudinal assessment of change in VO2max and maximal heart rate in master athletes

PURPOSE

The purpose of this study was to determine the longitudinal change in VO2max and HRmax in male and female master endurance runners and to compare these changes based upon gender, age, and change in training volume.

METHODS

Eighty-six male (53.9 +/- 1.1 yr) and 49 female (49.1 +/- 1.2 yr) master endurance runners were tested an average of 8.5 yr apart. Subjects were grouped by age at first visit, change in VO2max, and change in training volume. Measurements included body composition by hydrostatic weighing, maximal exercise testing on a treadmill, and training history by questionnaire. Data were analyzed by ANOVA and multiple regression.

RESULTS

VO2max and HRmax declined significantly regardless of gender or age group (P < 0.05). The rate of change in VO2max by age group ranged from -1% to -4.6% per year for men and -0.5% to 2.4% per year for women. Men with the greatest loss in VO2max had the greatest loss in LBM (-2.8 +/- 0.7 kg), whereas women with the greatest loss in VO2max demonstrated the greatest change in training volume (-24.1 +/- 3.0 km.wk-1). Additionally, women with the greatest loss in VO2max (-9.6 +/- 2.6 mL.kg-1.min-1) did not replace estrogen after menopause independent of age. HRmax change did not differ by VO2max change or training volume change in either gender.

CONCLUSIONS

In conclusion, these data suggest that VO2max declines in male and female master athletes at a rate similar to or greater than that expected in sedentary older adults. Additionally, these data suggest that maintenance of LBM and VO2max were associated in men, whereas in women, estrogen replacement and maintenance of training volume were associated with maintained VO2max.

Relationship between physiological loss, performance decrement, and age in master athletes

BACKGROUND

The use of master athletes to describe an idealized rate of physiological loss associated with aging is quite common. The results of such studies suggest that older athletes may be able to reduce the rate of decline in functional loss. The findings of such studies have been questioned due to their limited sample size and the age range and gender of their subjects.

METHODS

We examined a group of 146 male and 82 female master athletes over the age of 40 years. Physiological parameters included maximal oxygen uptake (VO2max), body composition, muscle strength, bone density, and blood chemistries. Medical histories and training records were obtained via questionnaire.

RESULTS

Results demonstrated gender differences in body composition, blood chemistries, blood pressure, VO2max, muscle strength, bone density, and performance (p <.05). All metabolic parameters for men and most for women demonstrated significant losses across the age range (p <.05). In addition, strength and performance for men and women and bone density for women declined significantly with age (p <.05). The demonstrated loss rates did not differ by gender.

CONCLUSIONS

Although limited by the lack of a sedentary comparison group, these data suggest that age-related losses in VO2max may not be different from data previously reported for older sedentary adults and that loss in muscle strength and performance with aging is not linear.

Serum and cerebrospinal fluid soluble Fas levels in clinical subgroups of multiple sclerosis

Elevated sFas levels have been described in multiple sclerosis (MS) patients with active disease. The aim of this study was to assess the diagnostic potential of serum and cerebrospinal fluid (CSF) sFas measurements in differentiating clinically defined MS patient subgroups. Levels of sFas and sFas indices were determined in patients with stable relapsing-remitting MS (RRMS), active RRMS, primary progressive MS (PPMS), secondary progressive MS (SPMS) and patients with inflammatory (IND) and noninflammatory neurological diseases (NIND). Serum sFas modulation over 32 weeks IFN-beta1a therapy was also investigated. Serum and CSF sFas levels and sFas indices were elevated in MS compared to NIND and IND patients. Within the MS group, serum and CSF sFas levels were highest in PPMS, with active RRMS patients demonstrating the highest sFas indices. This may reflect an ongoing disease process which is occurring acutely (active disease) or incessantly (progressive disease). IFN-beta1a induced a transient increase in circulating sFas following initiation of therapy. Whilst evidence was provided for variable sFas expression in clinical subgroups of MS, there was insufficient definition between the respective groups to advocate sFas measurements as a diagnostic marker of clinical subgroups of MS.

Traumatic Brown-Séquard-plus syndrome

BACKGROUND

In the 1840s Brown-Séquard described the motor and sensory effects of sectioning half of the spinal cord. Penetrating injuries can cause Brown-Séquard or, more frequently, Brown-Séquard-plus syndromes.

OBJECTIVE

To report the case of a 25-year-old man who developed left-sided Brown-Séquard syndrome at the C8 level and left-sided Horner syndrome plus urinary retention and bilateral extensor responses following a stab wound in the right side of the neck.

RESULTS

Magnetic resonance imaging demonstrated a low cervical lesion and somatosensory evoked potentials confirmed the clinical finding of left-side dorsal column disturbance. At follow-up, the patient's mobility and bladder function had returned to normal.

CONCLUSION

This patient recovered well after a penetrating neck injury that disturbed function in more than half the lower cervical spinal cord (Brown-Séquard-plus syndrome).

Oral inoculation of sheep with the agent of bovine spongiform encephalopathy (BSE). 1. Onset and distribution of disease-specific PrP accumulation in brain and viscera

Sixty-three Romney sheep aged 6 months, consisting of three groups (PrP(ARQ/ARQ), PrP(ARQ/ARR), and PrP(ARR/ARR)genotypes) of 21 animals, were infected orally with brain tissue from BSE-infected cattle. Sub-groups of the 21 PrP(ARQ/ARQ) animals were killed, together with uninfected controls 4, 10, 16, 22 or 24-28 (after the development of full clinical disease) months post-inoculation (mpi). One sheep from each of the two groups of four killed at 4 or 10 mpi were shown by immunohistochemical examination to possess disease-specific PrP accumulations in single lymph nodes. At 16 mpi, such accumulations were detected in two of four infected sheep in some viscera and in the spinal cord and brain. At 22 mpi, three of five infected sheep had widespread disease-specific PrP accumulations in all tissues examined, but the remaining two animals gave positive results only in the central nervous system. Clinical disease appeared at 20-28 mpi. Three sheep killed with advanced clinical signs showed widespread PrP accumulation in brain, spinal cord and peripheral tissues. These results confirmed that PrP(ARQ/ARQ) Romney sheep are susceptible to experimental infection with the BSE agent. The different sites at which initial PrP accumulations were detected suggested that the point of entry of infection varied. Once established, however, infection appeared to spread rapidly throughout the lymphoreticular system. The results suggested that in some BSE-infected sheep neuroinvasion occurred in the absence of detectable PrP accumulations in the viscera or peripheral nervous system. In contrast to cattle with BSE, however, most sheep showed disease-specific PrP accumulations in the lymphoreticular system. In this respect, BSE-infected resembled scrapie-infected sheep; it is possible, however, that future research will reveal differences in respect of targeting of cell types within the lymphoreticular and peripheral nervous systems. The PrP(ARQ/ARR)and PrP(ARR/ARR)sheep were also killed in sub-groups at intervals after inoculation. Up to 24 mpi, however, none of these animals showed disease-specific PrP accumulations. Further results will be reported later.

An assessment of the spectrum of disability and handicap in multiple sclerosis: a population-based study

OBJECTIVES

To establish the spectrum of disability and handicap in a population based sample of multiple sclerosis (MS) patients.

BACKGROUND

Much knowledge exists about the epidemiology of MS but, despite its importance for health and social service planning, there remains relatively little data on the extent and nature of disability and handicap in this population.

METHODS

In a prevalence study in the north-east of N. Ireland, 288 patients (Poser criteria) were identified. Disability and handicap were assessed using the Incapacity Status Scale and Environmental Status Scale of the Minimal Record of Disability for MS.

RESULTS

Both scales were completed for 248 (86%) of patients. Just 71 (29%) are fully independent in all basic ADL's of bathing, dressing, grooming and feeding. Fifty-seven (23%) are unable to climb a flight of stairs and 102 (42%) acknowledge problems with sexual function. Sixty-one (25%) were working essentially full-time and 53 (21%) had no external financial support. Forty-five (18%) had changed residence due to MS, 12 (5%) were institutionalised and 86 (35%) required assistance for at least 1 h/day with ADL's. Eighty-one (33%) were unable to drive a car or use public transport. Forty-two (17%) access community services for at least 1 h/day on average.

CONCLUSIONS

This data gives a clear indication of the considerable range of basic health and social issues in a typical MS community. Further work is required to establish patient perceptions of the adequacy of care provision and whether standards of care for MS patients are being met.

Monocyte-derived dendritic cells: a potential target for therapy in multiple sclerosis (MS)

Monocytes can differentiate into dendritic cells (DC), cells with a pivotal role in both protective immunity and tolerance. Defects in the maturation or function of DC may be important in the development of autoimmune disease. We sought to establish if there were differences in the cytokine (granulocyte-macrophage colony-stimulating factor and IL-4)-driven maturation of monocytes to DC in patients with MS and whether drugs used to treat MS affected this process in vitro. We have demonstrated that there is no defect in the ability of magnetic activated cell sorting (MACS)-purified monocytes from patients with MS to differentiate to DC, but equally they show no tendency to acquire a DC phenotype without exogenous cytokines. Interferon-beta1a prevents the acquisition of a full DC phenotype as determined by light and electron microscopy and by flow cytometry. Methylprednisolone not only prevents the development of monocyte-derived DC but totally redirects monocyte differentiation towards a macrophage phenotype. Evidence is evolving for a role for DC in central nervous system immunity, either within the brain or in cervical lymph nodes. The demonstrated effect of both drugs on monocyte differentiation may represent an important site for immune therapy in MS.

Interferon-beta1a administration results in a transient increase of serum amyloid A protein and C-reactive protein: comparison with other markers of inflammation

Putative markers of inflammation such as serum beta2-microglobulin and neopterin have been shown to be transiently upregulated following interferon-beta (IFN-beta) administration to multiple sclerosis (MS) patients. However, to date the role of the important inflammatory mediators serum amyloid A protein (SAA) and C-reactive protein (CRP) have not been described. Here we show that SAA but not CRP is elevated in relapsing-remitting MS patients compared to normal healthy individuals, and furthermore that both are transiently upregulated following intramuscular injection with IFN-beta1a (Avonex). This pattern of expression was found to parallel that of beta2-microglobulin and neopterin following injection and was mirrored by a selective activation of peripheral monocytes with respect to upregulation of receptors known to be involved in the inflammatory response (HLA-DR, CD16 and CD86). Injection of saline solution intramuscularly to six healthy control individuals did not produce a similar upregulation of any of the inflammatory markers investigated. Following IFN-beta1a injection, all inflammatory responses were attenuated at week 12 of therapy in comparison to those following the initial injection in a group of follow-up patients. In addition, IFN-beta1a injected on a weekly basis did not produce a sustained modulation of any of the markers investigated in patients treated for 32 weeks.

Multiple sclerosis in Northern Ireland: a historical and global perspective

The uneven worldwide distribution of multiple sclerosis has been of interest to epidemiologists, neurologists and statisticians for over a century, prevalence rates for the disease apparently being determined by variations in age, gender, geography, race and ethnic group. Northern Ireland has been recognised as an area of high MS prevalence since the truly seminal work of Allison and Millar almost 50 years ago. The most recent study in Northern Ireland was undertaken in 1996 and involved the neighbouring districts of Coleraine, Ballymena, Ballymoney and Moyle (population, 151,000). Overall, 254 definite and probable cases were identified (prevalence: 168.2/100,000) with a further 34 suspected cases (overall prevalence: 190.7/100,000). Females predominated (ratio, 2.1:1) and the average age at onset was 31.6 years. The highest age specific prevalence rate for females was in the 35-44 years old age group (519.6/100,000) and for males was in those aged 55-64 (292.3/100,000). The spectrum of disability was broad and 20% could be considered to have relatively "benign" disease. These figures sadly confirm that Northern Ireland has one of the highest and rising MS prevalence rates in the world and implies an enormous potential for societary costs.

Maximal aerobic power, lactate threshold, and running performance in master athletes

PURPOSE

This study sought to determine how lactate threshold (LT) is related to running performance in older male and female runners, if LT changes significantly with age, and if gender alters the relationship between LT and performance in older runners.

METHODS

Subjects were 168 master runners (111 men, 57 women) selected from a longitudinal study, who ran at least 10 miles x wk(-1) for 5 yr or more. VO2max was measured on a treadmill and body composition by hydrostatic weighing. Blood samples taken each minute of exercise were analyzed for lactate concentration and LT determined as the breakpoint in lactate accumulation. Performance times and training histories were self-reported by questionnaire.

RESULTS

Men had significantly greater body mass, fat-free mass (FFM), and VO2max (L x min(-1); mL x kg(-1) x min(-1)) than women. FFM and VO2max (L x min(-1); mL x kg(-1) x min(-1)) declined with age in both men and women. Running performance was significantly different between men and women and declined with age in both. LT (L x min(-1); mL x kg(-1) x min(-1)) was significantly different between men and women, and declined significantly with age in men, whereas LT (%VO2max) did not differ between men and women and increased significantly with age in both. VO2max (mL x kg(-1) x min(-1)) was the most significant predictor of performance in both men and women, whereas LT (L x min(-1)) added to the prediction of 5-km and 10-km performance in women.

CONCLUSION

The results of this study demonstrate that VO2max (mL x kg(-1) x min(-1)) is a better predictor of performance than LT in older male and female runners. Additionally, LT as a percentage of VO2max increases significantly with age.

An evaluation of interleukin genes fails to identify clear susceptibility loci for multiple sclerosis

Differential expression of interleukins may influence susceptibility to inflammatory diseases such as MS. IL-1a production is increased in MS patients during acute relapse, IL-2 receptor (IL-2R) secretion correlates with disease activity in several inflammatory disorders and is variable in MS. Both IL-4 and IL-10 expression vary significantly with relapse/remission in MS and IL-9 is postulated to inhibit steroid-induced apoptosis. To examine the influence of interleukin (IL) genes on MS susceptibility and clinical course, gene association studies using separate polymorphic microsatellite markers for il-1 alpha, il-2, il-2r beta, il-4 il-9 and il-10 were performed, incorporating 150-177 relapsing-remitting or secondary progressive MS (RR/SPMS) patients, 100-110 primary progressive (PPMS) patients and 152-210 controls. No significant differences existed in allele frequencies between either MS group and controls for any of the interleukin microsatellite markers studied, nor were statistically significant differences observed in PPMS vs. RR/SPMS for any marker. These data indicate that the IL-1 alpha, IL-2, IL-2R beta, IL-4, IL-9 and IL-10 genes are unlikely to be susceptibility loci for MS in this population.

Effect of platelet-derived growth factor receptor-alpha and -beta blockade on flow-induced neointimal formation in endothelialized baboon vascular grafts

The growth of neointima and neointimal smooth muscle cells in baboon polytetrafluoroethylene grafts is regulated by blood flow. Because neointimal smooth muscle cells express both platelet-derived growth factor receptor-alpha and -beta (PDGFR-alpha and -beta), we designed this study to test the hypothesis that inhibiting either PDGFR-alpha or PDGFR-beta with a specific mouse/human chimeric antibody will modulate flow-induced neointimal formation. Bilateral aortoiliac grafts and distal femoral arteriovenous fistulae were placed in 17 baboons. After 8 weeks, 1 arteriovenous fistulae was ligated, normalizing flow through the ipsilateral graft while maintaining high flow in the contralateral graft. The experimental groups received a blocking antibody to PDGFR-alpha (Ab-PDGFR-alpha; 10 mg/kg; n=5) or PDGFR-beta (Ab-PDGFR-beta; 10 mg/kg; n=6) by pulsed intravenous administration 30 minutes before ligation and at 4, 8, 15, and 22 days after ligation. Controls received carrier medium alone (n=8). Serum antibody concentrations were followed. Grafts were harvested after 28 days and analyzed by videomorphometry. Serum Ab-PDGFR-alpha concentrations fell rapidly after day 7 to 0, whereas serum Ab-PDGFR-beta concentrations were maintained at the target levels (>50 microg/mL). Compared with controls (3.7+/-0.3), the ratio of the intimal areas (normalized flow/high flow) was significantly reduced in Ab-PDGFR-beta (1.2+/-0.2, P<0.01) but not in Ab-PDGFR-alpha (2.2+/-0.4). Ab-PDGFR-alpha decreased significantly the overall smooth muscle cell nuclear density of the neointima (P<0.01) compared with either the control or Ab-PDGFR-beta treated groups. PDGFR-beta is necessary for flow-induced neointimal formation in prosthetic grafts. Targeting PDGFR-beta may be an effective pharmacological strategy for suppressing graft neointimal development.

Evaluation of the clinical utility of cerebrospinal fluid (CSF) indices of inflammatory markers in multiple sclerosis

OBJECTIVES

Accumulating evidence indicates significant heterogeneity in MS and soluble (s) adhesion molecules are postulated as markers of disease activity. We sought to evaluate intrathecal production of these and other molecules across the clinical spectrum of MS.

METHODS

CSF indices of IgG, sICAM-1, sVCAM-1, sE-selectin and sCD30 were calculated in 17 primary progressive (PPMS) patients, 15 secondary progressive patients (SPMS), 28 relapsing-remitting patients in relapse (RRMSR) and 14 RRMS patients in remission (RRMSNR) using commercially available ELISA kits. Patients had not received any immunomodulating therapy within the previous 6 months. MS patients were compared with 44 patients with non-inflammatory neurological diseases (NINDs).

RESULTS

The most sensitive CSF index at a 90% level of specificity was for IgG which had 93% sensitivity in RRMSR and 92% sensitivity in RRMSNR. Corresponding sensitivity in PPMS and SPMS was 71% and 73% respectively. None of the other indices had sensitivity >50% apart from sVCAM-1 (64% in RRMSR and 52% RRMSNR) and sCD30 (53% in PPMS).

CONCLUSIONS

Unsurprisingly the strongest association in MS was with the intrathecal production of IgG. Similar results in PPMS and SPMS may reflect comparable rates of progression in these 2 groups. Of the other molecules only intrathecal sVCAM-1 production is significantly associated with MS and only in relapsing-remitting disease.

The neuropathology of experimental bovine spongiform encephalopathy in the pig

In an experimental study of the transmissibility of BSE to the pig, seven of 10 pigs, infected at 1-2 weeks of age by multiple-route parenteral inoculation with a homogenate of bovine brain from natural BSE cases developed lesions typical of spongiform encephalopathy. The lesions consisted principally of severe neuropil vacuolation affecting most areas of the brain, but mainly the forebrain. In addition, some vacuolar change was identified in the rostral colliculi and hypothalamic areas of normal control pigs. PrP accumulations were detected immunocytochemically in the brains of BSE-infected animals. PrP accumulation was sparse in many areas and its density was not obviously related to the degree of vacuolation. The patterns of PrP immunolabelling in control pigs differed strikingly from those in the infected animals.

Genetic association studies of tumour necrosis factor alpha and beta and tumour necrosis factor receptor 1 and 2 polymorphisms across the clinical spectrum of multiple sclerosis

Allelic association studies with microsatellite markers around the tumour-necrosis factor (TNF) genes have demonstrated significantly different allele distributions of TNF markers (a and b) between relapsing-remitting/secondary progressive multiple sclerosis (MS) (RR/SPMS) patients and normal controls. Considering the suspected genetic and immunological heterogeneity in MS, we tested this association in primary progressive MS (PPMS) patients. Elevated levels of serum soluble TNF receptors (sTNF-R) are reported in patients with gadolinium enhancing lesions, and animal models suggest a possible therapeutic role of sTNF-RI in MS. Thus we performed similar association studies using markers for the TNF-R genes. Gene association studies were carried out on 199-216 normal controls, 174 RR/SPMS patients and 102 PPMS patients using polymorphic dinucleotide repeat TNF markers (a, b and d), and separate markers for TNF-RI and TNF-RII. Forward primers were fluorescently labelled, polymerase chain reaction (PCR) products were analysed on a fluorescent fragment analyser, and Genescan 672 software was used for allele sizing. Samples were typed for HLA-DR antigens using PCR technology and sequence-specific oligonucleotide probes. TNFa marker allele distributions differed significantly between PPMS patients and controls (P = 0.028), largely attributable to an increase in the 118-bp TNFa allele in PPMS patients (P = 0.00024). Allele distributions were similar in PPMS and RR/SPMS patients (P = 0.91). Logistic regression analysis, however, indicated that these associations were not independent of that with HLA-DRB1*15. For the TNFb marker, the 127-bp allele showed association with both patient categories (PPMS vs. controls, P = 0.010; RR/SPMS vs. controls, P = 0.027), whilst the 128-bp allele occurred more frequently in controls (PPMS vs. controls, P = 0.036: RR/SPMS vs. controls, P = 0.0009). As with the TNFa 118 bp allele, the association with TNFb was not independent of the HLA association. No association occurred with the TNFd marker, and there were also no significant differences in allele frequencies between MS groups and controls regarding the marker for TNF-RI or TNF-RII. In Northern Irish patients the TNF contribution to MS genetic susceptibility is therefore similar across the clinical spectrum of the disease but is not independent of the association with HLA-DRB1*15.

Changes in plasma cytokines induced by interferon-beta1a treatment in patients with multiple sclerosis

It has been postulated that the efficacy of interferon-beta1a in multiple sclerosis may be due to the induction of type 2 cytokines. In this report we demonstrate that after 3 months of therapy, there is no sustained alteration in the plasma levels of type 1 (IL-12, IL-1beta and TNF-alpha) or type 2 (IL-6, IL-10) cytokines, but rather repeated induction of both with each injection. Little alteration is seen in the profile of cytokines induced with time, despite a decline in side effects. This suggests that IFN-beta1a causes repeated transient modulation of cytokine expression, but no sustained deviation in the type 1/type 2 balance.

The inability of hormone replacement therapy or chronic running to maintain bone mass in master athletes

BACKGROUND

Previous studies have demonstrated equivocal findings on the effect of chronic running on bone mass in post-menopausal women. The purpose of this study was to determine the effect of chronic running alone and in conjunction with hormone replacement therapy (HRT) on bone mineral density (BMD) in postmenopausal women.

METHODS

Forty-three women [15 premenopausal 48.1 +/- .4 yrs (Pre); 13 postmenopausal 57.3 +/- 2.3 yrs (Post); and 15 HRT-treated postmenopausal 56.8 +/- 1.5 yrs (PostE)] served as subjects. All were chronic runners (duration > 5 yrs, > 10 miles per week). BMD was determined by dual energy x-ray absorptiometry, VO2 max on a treadmill, body composition by hydrostatic weighing, knee strength by KinCom dynamometer, and training and menstrual history by questionnaire. Analysis of covariance with Tukey post hoc tests was utilized to compare the groups.

RESULTS

The groups were similar in body weight, VO2 max, years training, and miles run per week. Pre and PostE did not differ in total or spine BMD. However, Pre had greater hip BMD than PostE (.973 +/- .03 vs .876 +/- .03 g/cm2; p < .05). As well, Pre had greater BMD of the hip (.973 +/- .03 vs .805 +/- .03 g/cm2; p < .05), spine (1.047 +/- .04 vs .870 +/- .04 g/cm2; p < .05), and total body (1.115 +/- .02 vs .996 +/- .03 g/cm2; p < .05) than Post.

CONCLUSIONS

These results suggest that (a) chronic running + HRT is insufficient to protect hip BMD and (b) chronic running alone provides no protection for bone mass in postmenopausal women.

Eccentric muscle action increases site-specific osteogenic response

PURPOSE

Strain magnitude is known to be a primary determinant of the osteogenic response to loading. However, whether bone adaptation to muscle loading is determined primarily by load magnitude is unclear. The purpose of this study was to determine the contribution of load magnitude from muscle action on the site-specific osteogenic response.

METHODS

Twenty young women (12 exercise, 8 control) served as subjects. Bone mineral density (BMD) of the whole body and mid-femur segment and body composition were determined by dual-energy x-ray absorptiometry. Knee extension and flexion strengths were determined on a KinCom dynamometer, with surface electromyography of the vastus lateralis muscle. Exercise subjects trained three times weekly for 18 wk on a KinCom. One leg trained using eccentric knee extension and flexion, and the opposite leg trained using concentric knee extension and flexion.

RESULTS

Eccentric exercise demonstrated greater force production with lower integrated electromyographic signal (IEMG) compared with concentric exercise. Significant increases in muscle strength occurred in both exercised legs (P < 0.05), which were of similar relative change. However, only the eccentric trained leg significantly increased mid-femur segment BMD (+3.9%, P < 0.05) and mid-thigh segment lean mass (+5.2%, P < 0.05).

CONCLUSIONS

These results suggest that eccentric muscle training is more osteogenic than concentric muscle training and that eccentric training is more efficient by attaining higher force production with lower IEMG.

CD80 (B7-1) and CD86 (B7-2) expression in multiple sclerosis patients: clinical subtype specific variation in peripheral monocytes and B cells and lack of modulation by high dose methylprednisolone

Autoimmune activation of T cells by central nervous system (CNS)-derived antigens is hypothesised to underlie neural damage in multiple sclerosis (MS) patients. The role of coreceptor mediated signalling is currently under investigation in order to further elucidate the immunopathogenic mechanisms implicated and to determine possible targets for immune modulation. We have investigated whether differential coreceptor (B7-1/CD80; B7-2/CD86; CD28) expression on circulating lymphocytes and monocytes is (i) a feature of distinctive clinical subtypes of MS (relapsing-remitting in remission/stable-RRMS; relapsing-remitting in relapse/relapsing-RRMS; primary progressive/PPMS), (ii) related to disease activity, and (iii) altered by high dose corticocosteroid treatment. CD80(+) B cells were significantly reduced (P<0.05) in PPMS (4.0+/-0.8%) compared with normal subjects (CON) (9.1+/-1.1%), stable-RRMS (6.7+/-0.7%) and relapsing-RRMS (7.8+/-0.9%) patients. Comparatively fewer monocytes from relapsing-RRMS patients expressed CD86 (relapsing-RRMS 50+/-4.9% vs. stable-RRMS 75.1+/-3.4%, PPMS 77. 7+/-3.2%, CON 72.1+/-3.6%/P<0.05). Otherwise expression of coreceptors did not vary significantly between the groups. A 3-day course of methylprednisolone therapy did not alter coreceptor expression, but did suppress monocyte and B cell HLA-DR expression. There is evidence for differential coreceptor expression on circulating B cells and monocytes in MS disease subtypes. The biological significance of these findings is discussed in relation to alternative theories regarding coreceptor functioning.

Benign multiple sclerosis? Clinical course, long term follow up, and assessment of prognostic factors

OBJECTIVE

To establish the characteristics of patients following a benign course of multiple sclerosis and evaluate the importance of potential prognostic factors. Also, an assessment of the value of the Kurtzke EDSS as a prognostic indicator has been undertaken in patients previously determined to have benign multiple sclerosis, after 10 years of follow up.

METHODS

A prevalence study in the Coleraine, Ballymena, Ballymoney, and Moyle districts of Northern Ireland used the Kurtzke expanded disability scale score (EDSS) in 259 patients with multiple sclerosis. Of these, 181 had had multiple sclerosis for>/=10 years, 36 having benign disease (EDSS</=3.0) >/=10 years after onset. Clinical and demographic details of the various patient groups, including the minimal record of disability, were compared. The 1987 study in Northern Ireland identified 33 patients with benign multiple sclerosis. Twenty eight were available for follow up in 1996 along with 42 contemporary non-benign patients.

RESULTS

Patients with benign multiple sclerosis were predominantly women (ratio 4.1:1 v 2.1:1) and younger at onset (25.8 v 31.2 years). Commonest symptoms at onset were sensory and optic neuritis (33.3% each). Patients with late onset (older than 40 years) were less likely to have a benign course, more likely to have a progressive course from onset, significantly more likely to have motor disturbance at presentation, and had a lesser female predominance. Optic neuritis was significantly more common in those with a younger age at onset. In the follow up study, patients with benign multiple sclerosis continued to have a more favourable course than non-benign counterparts but progression of disability and to the secondary progressive phase remained significant.

CONCLUSIONS

The association of female sex, early onset, and presentation with optic neuritis and sensory symptoms with a favourable course is confirmed. However, although the EDSS does provide a useful indicator of prognosis, the label "benign multiple sclerosis" is often temporary as apparently benign disease often becomes disabling.

Oral arginine does not stimulate basal or augment exercise-induced GH secretion in either young or old adults

BACKGROUND

Growth hormone (GH) helps maintain body composition and metabolism in adults. However, basal and peak GH decline with age. Exercise produces a physiologic GH response that is subnormal in elderly people. Arginine (Arg) infusion can augment GH secretion, but the efficacy of oral Arg to improve GH response to exercise has not been explored. We investigated whether oral Arg increases GH secretion in young and old people at rest and during exercise.

METHODS

Twenty young (Y: 22.1 +/- 0.9 y; SEM) and 8 old (O: 68.5 +/- 2.1 y) male and female subjects underwent three different trials following determination of their one-repetition maximum strength (1-RM); exercise only (EO; 3 sets, 8-10 reps at 85% of 1-RM; on 12 separate resistive lifts), Arg only (5.0 g), or Arg + exercise. Blood samples were collected between successive lifts, and GH (ng x ml(-1)) was determined via RIA.

RESULTS

In Y vs O: Basal GH secreted (area under the curve) was 543.6 +/- 84.0 vs 211.5 +/- 63.0. During EO, values were 986.6 +/- 156.6 and 517.8 +/- 85.5. Both were significantly lower in the older individuals (p < .05). Oral Arg alone did not result in any increase in GH secretion at rest (310.8 +/- 73.2 vs 262.9 +/- 141.2). When Arg was coadministered during exercise, GH release was not affected in either the young or old and appeared to be blunted in the young compared to the exercise only trial in the young.

CONCLUSION

Based upon these findings, we concluded that oral Arg does not stimulate GH secretion and may impair GH release during resistive exercise.

Relationship between tumour necrosis factor-alpha (TNFalpha) production and a specific multiple sclerosis (MS) associated TNF gene haplotype

OBJECTIVE

To determine if monocyte TNFalpha production from patients homozygous for a specific MS associated TNF gene haplotype is different from that produced in patients either heterozygous for, or without this haplotype.

BACKGROUND

The balance between pro- and anti-inflammatory cytokines is important in the clinical outcome of inflammatory reactions. Levels of TNFalpha, a pro-inflammatory cytokine, is raised in MS as well as being found in acute and chronic MS lesions. A previous population based study in Northern Ireland with polymorphisms spanning the TNF gene region identified a conserved MS associated haplotype in relation to three markers (130: 118: 127 TNF d:a:b) for which 19 MS patients were homozygous.

METHODS

Venous blood collected in EDTA to give a concentration of 10(-3) M was drawn from 16 patients with the conserved MS associated haplotype, 19 patients heterozygous for the haplotype and 17 patients without the haplotype. Mononuclear cells were separated and cultured by standard techniques and levels of TNFalpha and of TNF binding proteins I and II were determined by commercial enzyme-linked immunosorbent assays.

RESULTS

There were no significant differences in TNFalpha production in the 3 h (P = 0.28) or 24 h cultures (P = 0.18) or following stimulation with interferon-gamma (P = 0.17) between the group positive for the conserved haplotype and the group negative for this haplotype. There was also no significant difference when compared to the heterozygote group. No association was found between the MS associated haplotype and levels of either TNF binding protein. A greater proportion of patients with the conserved haplotype had a benign clinical course (P = 0.06).

CONCLUSION

We conclude that whilst a trend exists, we have found no significant association between peripheral TNFalpha production and a specific MS associated TNF haplotype in this population. Paradoxically this haplotype may also predict a more favourable clinical course.

Age-related blunting of growth hormone secretion during exercise may not be soley due to increased somatostatin tone

Age-related declines in growth hormone (GH) secretion may result from augmented somatostatin (SRIH) tone and/or diminished GH-releasing hormone (GHRH) secretion. We assessed GH release during exercise without and with pyridostigmine (PYR), which indirectly suppresses SRIH. GH levels were measured throughout exercise and recovery in 12 young men (mean +/- SEM, 20.8 +/- 0.4 years) and seven old men (66.1 +/- 1.9). The area under the GH curve (GH-AUC) was greater in young versus old men during a short-term maximal exercise test (12.9 +/- 2.8 v 1.5 +/- 0.2 ng x min(-1) x mL(-1), P = .002) and a 1-hour 60% maximal (submaximal, 10.0 +/- 1.5 v 3.0 +/- 1.0 ng x min(-1) x mL(-1), P = .001) cycle exercise bout. PYR increased the GH-AUC in young and old men during maximal (20.9 +/- 5.2 v 4.9 +/- 1.8) and submaximal (12.3 +/- 1.6 v 4.7 +/- 1.5) exercise (P < .05). The greater GH response to maximal versus submaximal exercise suggests a role for adrenergic modulation of GHRH during exercise. However, the failure of PYR to restore the responses of the old to those of the young suggests that increased SRIH tone does not completely explain the age difference in GH secretion during exercise.

A study of the HLA-DR region in clinical subgroups of multiple sclerosis and its influence on prognosis

OBJECTIVE

To investigate the HLA-DR associations in relapsing-remitting/secondary progressive multiple sclerosis (RR/SPMS) and primary progressive MS (PPMS). The HLA-DR2 allele (or its split, HLA-DRB1*15) is felt to be a risk factor for MS, rather than a genetic marker for the population of origin. Some studies have indicated a different HLA-DR antigen profile in PPMS patients compared with those having an initially relapsing-remitting course, only those with relapsing disease showing an increase in HLA-DR2. Association of PPMS with DR4 has been suggested. Several DR alleles have also been felt to influence the prognosis in MS.

METHODS

Genomic DNA was prepared from peripheral blood of 202 RR/SPMS patients identified in a population-based prevalence study, 102 PPMS patients identified throughout Northern Ireland and 398 normal controls (Nor) matched for the postcode areas of those identified in the prevalence study. Samples were typed for the HLA-DR antigens using polymerase chain reaction (PCR) technology and sequence specific oligonucleotide probes (SSOP).

RESULTS

A high incidence of HLA-DRB1*15 was found in each MS group - PPMS (63.73%), RR/SPMS (66.83%) - compared with normals (32.41%), (PPMS vs. Nor, P<0.0001: RR/SPMS vs. Nor, P<0.0001). HLA-DRB1*04 occurred at a lower incidence in both MS groups compared with controls - RR/SPMS (22%), PPMS (30%), Nor (35%). Overall, highly significant differences existed across the full HLA-DR allele distribution (RR/SPMS vs. Nor, P<0.0001, df=12: PPMS vs. Nor, P=0.0007, df=12). No significant differences existed between PPMS and RR/SPMS (P=0.47, df=12), and the allele distributions in benign and aggressive MS were similar.

CONCLUSIONS

These data suggest that in this population, HLA-DRB1*15 is indeed associated with PPMS and that PPMS has a HLA-DR profile distinct from the normal population but not from those with an initially relapsing-remitting course. No single allele is associated with either a good or poor prognosis.

Lack of association of transforming growth factor (TGF)-beta 1 and beta 2 gene polymorphisms with multiple sclerosis (MS) in Northern Ireland

OBJECTIVE

To examine the influence of TGF-beta genes on MS susceptibility.

BACKGROUND

TGF-beta, of which three homologous isoforms exist (1, 2 and 3), is a strongly immunosuppressive cytokine-inhibiting expression of pro-inflammatory cytokines and blocking cytokine induction of adhesion molecules. TGF-beta delays onset of EAE and TGF-beta 1 gene knockout mice develop fatal multifocal inflammatory disease. High TGF-beta levels exist during MS remission whilst E-selectin, whose expression is inhibited by TGF-beta, is found at higher levels in primary progressive disease (PPMS) and it is postulated that the unremitting course of PPMS may be due to low levels of TGF-beta.

METHODS

Gene association studies using separate polymorphic microsatellite markers for TGF-beta 1 and TGF-beta 2 were performed, incorporating 151 relapsing-remitting or secondary progressive MS (RR/SPMS) patients, 104 PPMS patients and 159 normal controls (Nor). Forward primers were 5' end-labelled with 6-Fam, PCR products were analysed on an Applied Biosystems 373A fluorescent fragment analyser and Genescan 672 software was used for allele sizing.

RESULTS

No significant differences existed in allele frequencies between either MS group and controls regarding the TGF-beta 1 marker: RR/SPMS vs Nor (P = 0.48, df = 8); PPMS vs Nor (P = 0.34, df = 8). Similarly there were no associations demonstrated with the TGF-beta 2 marker: RR/SPMS vs Nor (P = 0.24, df = 2); PPMS vs Nor (P = 0.53, df = 2).

CONCLUSION

These data indicate that TGF-beta 1 and beta 2 genes are not loci influencing MS susceptibility, either RR/SPMS or PPMS, in this population.

Serum soluble adhesion molecules in multiple sclerosis: raised sVCAM-1, sICAM-1 and sE-selectin in primary progressive disease

Leucocyte invasion into the central nervous system in multiple sclerosis (MS) is complex, involving T-cell/endothelium interaction dependent upon initial adhesion mediated by molecules such as E-selectin, L-selectin, intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-(VCAM-1). Circulating levels of these can be measured by sensitive enzyme-linked immunoassay (ELISA) techniques. To assess whether serum concentrations of soluble adhesion molecules vary across the spectrum of patients with relapsing-remitting (RR), secondary progressive (SP) and primary progressive (PP) MS, we measured circulating levels of soluble (s)E-selectin, sL-selectin, sICAM-1 and sVCAM-1 in serum obtained from 78 PPMS patients, 71 patients with RRMS, 65 patients with SPMS and 66 patients with other neurological disease using commercially available ELISA systems. Levels of serum sVCAM-1 were significantly elevated in PPMS compared with RRMS in remission (P = 0.0001) and in relapse (P = 0.0001), whilst sICAM-1 was significantly elevated in PPMS compared with all other MS groups (vs SPMS, P = 0.006; vs RRMS in relapse, P = 0.003; vs RRMS in remission, P = 0.0001). Serum sE-selectin levels were significantly higher in PPMS compared with all other groups except inflammatory neurological disease (IND) [vs SPMS, P = 0.029; vs RRMS in relapse, P = 0.002; vs RRMS in remission, P = 0.001; vs non-inflammatory neurological disease (NIND), P = 0.002; vs IND, P = 0.076]. In PPMS there was no correlation between levels of any adhesion molecule and disability or disease duration. These results provide evidence for significant immunological heterogeneity in MS and suggest that different leucocyte/endothelial cell interactions may be active in various MS subgroups. It also challenges the hypothesis that PPMS is a less inflammatory form of the disease.