Effects of piroxicam and D-penicillamine on T lymphocyte subpopulations, natural killer cells and rheumatoid factor production in rheumatoid arthritis

Rheumatoid arthritis and systemic lupus erythematosus: Pathophysiological mechanisms related to innate immune system

Rheumatoid arthritis and systemic lupus erythematosus are two highly prevalent autoimmune diseases that generate disability and low quality of life. The innate immune system, a long-forgotten issue in autoimmune diseases, is becoming increasingly important and represents a new focus for the treatment of these entities. This review highlights the role that innate immune system plays in the pathophysiology of rheumatoid arthritis and systemic lupus erythematosus. The role of the innate immune system in rheumatoid arthritis and systemic lupus erythematosus pathophysiology is not only important in early stages but is essential to maintain the immune response and to allow disease progression. In rheumatoid arthritis, genetic and environmental factors are involved in the initial stimulation of the innate immune response in which macrophages are the main participants, as well as fibroblast-like synoviocytes. In systemic lupus erythematosus, all the cells contribute to the inflammatory response, but the complement system is the major effector of the inflammatory process. Detecting alterations in the normal function of these cells, besides its contribution to the understanding of the pathophysiology of autoimmune diseases, could help to establish new treatment strategies for these diseases.

Inhibition of human B cell activation by a novel nonsteroidal anti-inflammatory drug, indometacin famesil

Indometacin farnesil (INF) is a prodrug of indomethacin (IND) designed to reduce the occurrence of side-effects by esterification of the carboxyl group on IND with farnesol. Previous studies have shown that INF has the characteristics of disease-modifying anti-rheumatic drug (DMARD) in that it has a component of slow-acting effect in treatment of rheumatoid arthritis (RA), in which abnormal B cell functions are considered to be involved. The current studies therefore examined the effects of INF on human B cells. Ig production was induced from highly purified B cells obtained from healthy donors by stimulation with Staphylococcus aureus Cowan I (SA) plus IL-2. T cell proliferation and IFN-gamma production were induced from highly purified T cells by stimulation with immobilized mAb to CD3. At pharmacologically attainable concentrations, INF, but not IND, suppressed the production of IgM and IgG of B cells, whereas neither suppressed the T cell proliferation and IFN-gamma production. The inhibition of Ig production by INF is not due to its IND structure, but is most likely due to its farnesil component, since farnesol alone comparably suppressed the Ig production. INF and farnesol did not suppress the expression of early activation markers, including CD98, CD25, and CD71, on SA-stimulated B cells, but appeared to inhibit the maturation of B cells following the initial activation. These results indicate that INF preferentially suppresses the human B cell functions. Thus, the data suggest that INF may have more beneficial effects than IND in treatment of RA.

Hybrid functional electrical stimulation orthosis system for the upper limb: effects on spasticity in chronic stable hemiplegia

A new hybrid functional electrical stimulation orthosis system for the upper limb has been designed to allow for ease of use in the home as a daily treatment modality, as well as offer the opportunity for function enhancement. In a pilot study, the system was used by ten patients with chronic stable hemiparesis secondary to cerebral vascular accident and head injuries. The patients were referred by their treating physicians or therapists after meeting the inclusion criteria of good general health, being greater than one year after head injury, or being ten months post-stroke, with no observed neurologic changes in the prior six weeks. Each of these patients had received prolonged physical therapy, either continuous from the initial inpatient rehabilitation treatment or on an intermittent basis over a period of years. The baseline status for factors related to increased muscle tone, i.e., passive range of motion at the wrist and elbow, posture at rest, posture immediately following activity, and spasticity were quantified before the treatment protocol with the functional electrical stimulation orthosis. Active range of motion and tests of functional use of the involved upper limb were also assessed. The patients were instructed in the protocol, trained in the use of the system, and then used the electrical orthosis at home for up to several hours per day. Follow-up assessments were at six months. A statistically significant improvement was noted in all muscle tone/spasticity parameters measured. A separate report will describe the effects on voluntary motion and functional capabilities.

Suppression of flexor reflex by transcutaneous electrical nerve stimulation in spinal cord injured patients

The effect of transcutaneous electrical nerve stimulation (TENS) applied to the area of the sural nerve on the early and late electromyographic component of the flexor reflex was studied in 20 patients with complete and incomplete transversal spinal cord injuries. A marked, progressive, and prolonged decrease of both reflex components was observed in most patients. The early component was decreased less than the late reflex component immediately following the end of TENS, while further decrement of both components was observed 30 min after the end of TENS. The placebo stimulation in 4 patients revealed no decrease, or only a less marked decrease in reflex responses. The marked suppressive effect of TENS cannot be attributed to the potentiated habituation of the reflex responses alone. The induced inhibitory processes seem to be at least partially localized at the segmental level of the spinal interneuron system.

Upper limb functional electrical stimulation for walker ambulation in hemiplegia: a case report

Electrical stimulation has been sporadically used in the treatment of hemiplegia. Reported benefits include decreasing spasticity, providing a supplementary means for range of motion exercises, increasing strength, and improving local blood flow in a paretic or paralyzed limb. Some studies have also shown functional gains in the hemiplegic upper limb following treatment with electrical stimulation. Nevertheless, there have been very few reports of the use of neuromuscular stimulation to achieve new hemiplegic upper limb activity not possible without the electrical stimulation. This is a case report of a head injury patient who was able to begin ambulation with a walker, without physical assistance, for the first time in the 16 yr since his injury. A new electrical stimulation device (Handmaster) initially used therapeutically, and then functionally, provided a reliable, strong grasp and release and was instrumental in achieving the new level of function. The device proved to be easy to use in the home, giving the patient microprocessor-controlled therapeutic and patterned functional electrical stimulation.

Pulsed electric current enhances the phorbol ester induced oxidative burst in human neutrophils

Oxidative burst (OB) response in human neutrophils, measured with chemiluminescence (CL), has been used to determine whether pulsed electric current (PEC) might induce a functional response in these electrically nonexcitable cells, and also whether it might modify cellular response to tumor-promoting phorbol ester (PMA). Five minutes of PEC treatment caused no significant changes in neutrophil CL levels in HBSS (1.2 mM Ca2+ concentration) as well as in HBSS-EGTA, where the extracellular Ca2+ concentration was reduced to less than 30 nM. The CL level of PMA-activated neutrophils in HBSS was 52% higher than in HBSS-EGTA. In HBSS the CL level, after the combined PMA and PEC treatment, was 53% higher than in PMA-alone-treated neutrophils. Activation of the OB in HBSS-EGTA with PMA and PEC was 13% higher than in solely PMA treated neutrophils. The results suggest that in neutrophil OB response, the PEC effect is closely related with cellular calcium mobilization, since depletion of extracellular Ca2+ decreased the PEC effect.

The rheumatoid factor: an analysis of clinical utility

The rheumatoid factor (RF) is a frequently ordered diagnostic test, yet it possesses significant limitations in sensitivity, specificity, and predictive value. Recognition of these limitations could improve the test's utility by encouraging more selective test ordering and more circumspect interpretation of test results. An analysis of 563 requests for RF from a teaching hospital revealed a positive predictive value of only 24% to 34%. The RF performs best under conditions of moderate pretest likelihood of rheumatoid arthritis, and otherwise has rather limited clinical utility.

D-penicillamine

D-Pen represents an effective treatment for a proportion of patients with RA and PSS. Its status in the treatment of juvenile RA is uncertain. The best results will be obtained by a skillful, careful physician maintaining careful surveillance for toxicity. Neither the mode of action nor the mechanisms of toxicity are well understood in RA. Consequently, safer and more effective analogues of D-pen have not been produced.

Relationship between clinical efficacy and laboratory correlates of inflammatory and immunologic activity in rheumatoid arthritis patients treated with nonsteroidal antiinflammatory drugs

Eighteen rheumatoid arthritis (RA) patients, who had been treated with nonsteroidal antiinflammatory drugs (NSAIDs) only, were enrolled in a 12-week, open-label, randomized protocol to determine whether clinical responses might be associated with improvement in laboratory measures of inflammation and immunologic activity in RA patients treated with NSAIDs. Following a 2-week drug washout period, patients were given either long-acting ibuprofen (2,400 mg/day) or flurbiprofen (200 mg/day); clinical, laboratory, and immunologic assessments were done biweekly for 10 weeks. A clinical efficacy index, utilizing a combination of measures of disease activity, identified 7 "responders" and 10 "nonresponders" (1 patient discontinued therapy because of a rash). Flow cytometric analysis revealed no abnormalities in the numbers of circulating CD3+, CD4+, or CD8+ lymphocytes in the 17 patients. The density of these T cell markers at enrollment was similar in patients and control subjects. However, following the 2-week drug washout, significant worsening of morning stiffness, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) was accompanied by a significant decrease (P less than or equal to 0.05) in the density of these T cell surface determinants, as is characteristic of activated T cells. After 10 weeks of NSAID therapy, increased density of CD3, CD4, and CD8 was observed in 47%, 73%, and 50% of the patients, respectively. However, in only the responders was the density of these T cell surface markers increased significantly (P less than or equal to 0.04). The responders, but not the nonresponders, also demonstrated significant reductions in the ESR, CRP level, serum IgM rheumatoid factor (RF) titer, and spontaneous synthesis of RF by lymphocytes in vitro (P less than or equal to 0.05). There were significant correlations between improvements in the clinical parameters (50-foot walk time, joint score, and global assessment) and reductions in the ESR, CRP level, and serum RF titer (P less than or equal to 0.05). These findings demonstrate that clinical improvement in RA patients treated with NSAIDs may be associated with the disappearance of phenotypically activated circulating T cells and functionally activated B cells, as well as with reductions in acute-phase reactants and serum RF titers.

Correlation of serologic indicators of inflammation with effectiveness of nonsteroidal antiinflammatory drug therapy in rheumatoid arthritis

Forty-seven patients with rheumatoid arthritis (mean duration 5.7 years) who were receiving neither disease-modifying drugs nor corticosteroids were enrolled in a 12-week, multicenter study of the relationship between clinical and serologic measures of disease activity in patients taking nonsteroidal antiinflammatory drugs. After a 2-week drug washout period, patients received flurbiprofen (200 mg/day) or sustained-release ibuprofen (2,400 mg/day) for a 10-week trial. Clinical response was assessed biweekly using standard clinical parameters, including 50-foot walk time, tender joint score, duration of morning stiffness, and global assessment of disease activity and pain (by both the patient and the physician). Patients were classified as responders if there was greater than or equal to 30% improvement in at least 3 of the 4 clinical measures of disease activity. Thirty patients completed at least 8 weeks of therapy; there were 12 responders and 18 nonresponders. Of the laboratory parameters examined, the responders, but not the nonresponders, demonstrated significant reductions (from postwashout values) in levels of IgM rheumatoid factor and C-reactive protein (CRP), along with significant increases in the number of circulating lymphocytes and decreases in the number of circulating granulocytes (P less than or equal to 0.05). In contrast, the nonresponders demonstrated either no change or worsening of the laboratory correlates of disease activity. The responders also appeared to have more aggressive disease at baseline, with significantly more painful joints, greater 50-foot walk times, elevated CRP values, and elevated erythrocyte sedimentation rates (P less than or equal to 0.05). These data suggest that there is a subset of rheumatoid arthritis patients in whom clinical improvement with nonsteroidal antiinflammatory drug therapy is associated with significant reductions in IgM rheumatoid factor and CRP levels.

Modulation of human natural killer cell function by cytokines and rheumatic disease

The activity of natural killer (NK) cells can be modified by a number of factors that either increase or suppress cytotoxicity. We have investigated in detail the cytokine induced killing of a NK resistant renal carcinoma cell line Cur by human NK cells. Preincubation of peripheral blood mononuclear cells with interferon alpha (IFN alpha), interleukin 2 (Il-2), interleukin 1 (Il-1) and tumor necrosis factor alpha greatly increased the rate and magnitude of Cur killing. Positively selected CD16 (+) cells were found to respond to cytokine stimulation and to mediate Cur killing. The effects of Il-2 and IFNa could be upregulated by costimulation of effector cells with Il-1 or TNF alpha. It was shown that TNF alpha induced Il-2 receptor expression on CD16(+) cells alone and even more in combination with Il-2. Studies of NK cell function in various rheumatic diseases revealed reduced NK cytotoxicity in peripheral blood and synovial fluid (SF), both in rheumatoid arthritis (RA) and juvenile rheumatoid arthritis (JRA). By contrast, normal NK function was found in patients with ankylosing spondylitis (AS) and psoriatic arthritis. A discordance with regard to the percentage of Leu 7 positive mononuclear cells and NK function in peripheral blood and SF was demonstrated. Minimal expression of Leu 7 positive cells and cytotoxicity was present in synovial membranes. NK function in rheumatic disease was largely independent of drug therapy. Natural killer (NK) cells are a subset of lymphocytes that mediate spontaneous cytotoxicity against certain tumor and virus infected cells without any known prior sensitation.(ABSTRACT TRUNCATED AT 250 WORDS)