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Richard A Rudick

Publications and source records attributed to Richard A Rudick.

12 recordsLinked to original sources
PubMed2004

Defining interferon beta response status in multiple sclerosis patients.

IFN-beta is effective in reducing relapses and magnetic resonance imaging (MRI) lesions in multiple sclerosis (MS). It is assumed that individual therapeutic responses vary, but methods to identify IFN-beta responsiveness have not been validated. Our objective was to evaluate methods to classify IFN-beta responder status using relapses and MRI lesions. Data was analyzed from 172 patients who were followed up in a placebo-controlled clinical trial of IFN-beta1a for 2 years. Patients were classified as responders or nonresponders using (1) the number of relapses during the 2-year trial; (2) the number of new T2 lesions after 2 years; and (3) the number of gadolinium-enhancing lesions at year 1 and year 2 on study. Outcomes included 2-year change in the Expanded Disability Status Scale, Multiple Sclerosis Functional Composite, and brain parenchymal fraction. We found that subgroups with high on-study relapse numbers had more disease progression, differences between responder subgroups were similar in the IFN-beta1a and placebo arms. In contrast, subgroups with high numbers of new MRI lesions had significantly more disease progression only in the IFN-beta1a arm. Baseline characteristics failed to account for differential outcome. New MRI lesion activity during IFN-beta1a treatment correlates with poor response to IFN-beta1a. MRI classification may facilitate rational therapeutic decisions, better clinical trial designs, and studies correlating biomarkers with therapeutic response.

Adult↗
PubMed2004

Impact of disease-modifying therapies on brain and spinal cord atrophy in multiple sclerosis.

Brain and spinal cord atrophy occur early in the course of multiple sclerosis (MS) and continue throughout this lifelong illness, resulting in substantial parenchymal tissue loss at later disease stages. Treatments that slow or prevent atrophy may reduce disability progression in the long term. Disease-modifying agents (DMAs) such as interferon beta-1b (IFNbeta-1b), IFNbeta-1a, and glatiramer acetate inhibit inflammatory events believed to initiate and perpetuate the disease process. DMAs have been shown to inhibit aspects of MS related to brain inflammation such as relapses and gadolinium-enhanced lesions. Because brain inflammation has been linked to irreversible brain tissue injury, DMAs should be effective in reducing the rate of brain atrophy progression. Weekly IFNbeta-1a (Avonex or Rebif) has been shown to slow the rate of brain atrophy; a large study of a frequent injection regimen with IFNbeta-1a (Rebif) showed continued atrophy progression despite IFNbeta-1a at a rate similar to placebo-treated patients. It is not clear why weekly treatment regimens with lower total doses of IFNbeta-1a would show beneficial effects on brain atrophy compared with frequent injections with larger weekly doses. This article reviews results of clinical trials that have examined the effects of DMAs on brain and spinal cord atrophy in patients with MS. Some of these agents have demonstrated positive effects in well-controlled studies, suggesting that anti-inflammatory therapy can delay or prevent the emergence of irreversible central nervous system pathology.

Adjuvants, Immunologic↗
PubMed2003

Biologic impact of interferon antibodies, and complexities in assessing their clinical significance.

The relevance of neutralizing antibodies (NAb) to interferon-beta (IFNbeta) for patients with MS treated with IFNbeta injections has been controversial. Published data from several double-blind, randomized clinical trials demonstrate that disease activity in IFNbeta-treated patients with MS is similar to placebo-treated patients within the same study. This observation is easily understood by other studies that demonstrate attenuation of the biologic response to IFNbeta injections in patients who are NAb positive. Because of the period over which antibodies develop, however, studies will demonstrate an impact of IFNbeta NAb only after the initial 18 months of therapy. Further, because the effects of IFNbeta on MS disease activity and progression are partial, large sample sizes are required to demonstrate clinical correlates of NAb. Therapeutic decisions related to disease management for patients with MS must consider IFNbeta NAb.

Antibodies↗
PubMed2003

Atrophy is detectable within a 3-month period in untreated patients with active relapsing remitting multiple sclerosis.

BACKGROUND: Atrophy is recognized as a measure of destructive changes in multiple sclerosis (MS). The time course and pathologic mechanisms of atrophy development are not well understood. Significant atrophy was reported to occur within 9 to 12 months in relapsing remitting MS. OBJECTIVES: To test whether atrophy can be detected over short time intervals, and to evaluate its relationship to inflammation. DESIGN AND METHODS: Prior to randomization to a treatment trial, 138 untreated patients with relapsing remitting MS had 3 magnetic resonance imaging scans within a mean +/- SD follow-up of 76 +/- 20.2 days. Brain parenchymal fraction (BPF), a normalized measure of whole brain volume, the proportion of active (gadolinium-enhancing) scans, and the volume of T1-weighted gadolinium-enhancing and T2-weighted hyperintense lesions were determined at all time points. An annualized atrophy rate was estimated by calculating a regression slope. RESULTS: The median Expanded Disability Status Scale score was 3.5, the mean disease duration was 7.6, and the mean age was 38.5 years. The BPF decreased significantly by -0.229% from scan 1 to scan 3, while the proportion of active scans remained high (65%, 63%, and 67%). The BPF change was only weakly correlated to the volume of T1-weighted gadolinium-enhancing lesions in scan 1 (r = -0.185). The estimated annualized atrophy rate was -1.06% (95% confidence interval, -1.50% to -0.62%). CONCLUSIONS: The annualized atrophy rate found in this study is comparable with rates reported previously. Measurements of BPF allow detection of atrophy over short time intervals in active disease. The short-term relationship of inflammation to atrophy development was weak. Brain parenchymal fraction might be a promising measure in future phase 2 studies of agents, with an expected effect on tissue-destructive pathologic mechanisms of MS.

Adult↗
PubMed2003

Interferon gamma responses to myelin peptides in multiple sclerosis correlate with a new clinical measure of disease progression.

The relationship between autoreactivity to myelin antigens and disease progression in multiple sclerosis (MS) is not fully understood. We addressed this relationship by cross-sectionally comparing an objective measure of MS disability with immune cytokine responses to myelin proteins. The ELISPOT assay was used to determine the ex vivo interferon gamma (IFNgamma) and interleukin-10 (IL-10) production by peripheral blood mononuclear cells (PBMCs) in response to peptides spanning the entire proteolipid protein (PLP) and myelin basic protein (MBP) molecules in 20 patients with relapsing-remitting (RR) MS and 27 age- and sex-matched healthy controls. MS patients showed significantly higher MBP-induced IFNgamma responses and PLP-induced IL-10 responses compared with healthy controls. Using the Multiple Sclerosis Functional Composite (MSFC), a new multifactorial measure of disability, MS patients showed a significant correlation between the IFNgamma response to PLP peptides and MBP peptides, and disability. In contrast, in MS patients, there was no correlation between the MSFC and the response to unrelated control antigens or mitogens. These data show that myelin-specific T lymphocytes secreting the inflammatory cytokine IFNgamma correlate with functional impairment in MS, supporting an antigen-specific link between the immune response to myelin and disability in MS.

Adolescent↗
PubMed2003

Interferon-beta 1a does not reduce expression of CCR5 and CXCR3 on circulating T cells.

The expression of CCR5 and CXCR3, two chemokine receptors involved with homing of T cells to inflamed tissue, was examined longitudinally on CD4+ and CD8+ T cells in patients with a first demyelinating event of the central nervous system (CNS) randomized to receive i.m. injections of interferon-beta1a (IFN-beta1a) or placebo. Blood for analysis was collected before and 48 h after injection at baseline and after 3 and 12 months of treatment. The results showed that treatment with IFN-beta1a did not affect numbers of T cells expressing CCR5 and CXCR3 during the first 12 months of treatment, either at the peak of biological response or at the trough of interferon effect, at steady-state.

CD4-CD8 Ratio↗
PubMed2003

Flow cytometric analysis of chemokine receptor expression on cerebrospinal fluid leukocytes.

Collection of cerebrospinal fluid (CSF) from the lumbar subarachnoid space is a routine procedure in clinical neurology, providing an opportunity to obtain hematogenous cells from the central nervous system environment in vivo. The ability to study individual cells in samples with low cell numbers has made flow cytometry an attractive method for studies of chemokine receptor expression on such cells. Several methodological variables such as staining temperature and cell isolation techniques may, however, influence the final outcome of the staining. In addition, low numbers of cells in the normal lumbar CSF, together with a tendency of CSF cells to decay rapidly after sampling, require meticulous handling of the samples. Here, we describe the methodology used in our laboratory to study chemokine receptor expression on cells in paired samples from peripheral blood and CSF using flow cytometry.

Antibodies, Monoclonal↗
PubMed2003

Expression of CCR2, CCR5, and CXCR3 by CD4+ T cells is stable during a 2-year longitudinal study but varies widely between individuals.

Blockade of chemokine receptors (CKRs) has recently emerged as a possible pathway for therapeutic intervention in disease. In the present report, the expression of CCR2, CCR5, and CXCR3, associated with migration of mononuclear cells to inflamed tissue, was determined on CD4+ T cells in a 2-year longitudinal study of healthy volunteers using flow cytometry. Large interindividual variations in the expression of these receptors on CD4+ T cells were observed, whereas levels remained remarkably stable over time within subjects. The expression of CCR2, CCR5, and CXCR3 on CD4+ T cells was directly proportional to percentages of CD45RO(hi)/CD4+ T cells. In addition, highly significant associations between levels of CCR2, CCR5, and CXCR3 on CD4+ T cells were demonstrated in individual subjects, implying a common mechanism for regulating the expression of these CKRs on circulating T cells. These associations were not due to coexpression of CKRs on individual CD45RA-/CD4+ T cells. The results provide insight into the regulation of CKR expression on CD4+ T cells in vivo, and suggest that major fluctuations of CKR expression in individuals are uncommon.

Adult↗
PubMed2003

Factors that predict health-related quality of life in patients with relapsing-remitting multiple sclerosis.

Health-Related Quality of Life (HRQoL) research is gaining acceptance in the field of multiple sclerosis (MS). Little is known about what precipitates quality of life change. It was hypothesized that physical aspects of quality of life decline with worsening objective disease measures and psychosocial aspects remain relatively stable regardless of change in objective measures. These assumptions are tested using data from a Phase 3 study of relapsing-remitting MS patients treated with interferon beta-1a and reassessed approximately eight years after study initiation. The Sickness Impact Profile (SIP) questionnaire is the generic quality of life measure used in this study. Three summary scores of the SIP (Physical, Psychosocial, and Total scores), Expanded Disability Status Scores, Multiple Sclerosis Functional Composite, and Brain Parenchymal Fraction were determined at baseline, year 2, and after an average of 8.1 years from study entry. SIP data collected during a clinic visit were available from 137 of the original 172 participants. All objective indicators worsened by follow-up. SIP Physical and Total scores significantly worsened from baseline to follow-up. SIP Psychosocial showed nonsignificant worsening. Regression analysis indicated that final measures of SIP Physical and Total scores were most strongly associated with change in objective measures and follow-up SIP Psychosocial was most strongly related to earlier scores on the same measure.

Adjuvants, Immunologic↗
PubMed2002

Sex differences in cytokine responses to myelin peptides in multiple sclerosis.

Many autoimmune diseases preferentially affect women; however, the underlying mechanisms for the sex differences are poorly understood. We examined sex-dependent differences in the immunologic response to myelin proteins in 22 multiple sclerosis (MS) patients and 22 healthy controls. Using ELISA spot assay (ELISPOT) methodology, interferon (IFN) gamma and IL-5 secretions were examined at the single cell level in response to overlapping proteolipid protein (PLP) peptides. As previously reported, we observed an overall disease effect in the IFNgamma response, such that MS patients were significantly higher than controls. With respect to PLP-induced IFNgamma secretion, both MS and control females responded higher than their corresponding males. Female MS patients demonstrated the highest responses compared to MS males or healthy controls of either sex. Although MS females had high IFNgamma responses to PLP, they had no IL-5 responses at all, suggesting strong Th1 skewing. In contrast, MS males had more IL-5 than control males, who lacked IL-5 responses. These IL-5 responses suggested that disease and gender are not independent, but rather interact to influence the cytokine response to myelin. The data suggest a gender bias towards Th1 responses in MS, which may contribute to the female predominance in this disease.

Adult↗