Bactericidal/permeability-increasing protein and cathepsin G are the major antigenic targets of antineutrophil cytoplasmic autoantibodies in systemic sclerosis

OBJECTIVE: To study the prevalence and antigenic specificity of antineutrophil cytoplasmic autoantibodies (ANCA) in patients with systemic sclerosis (SSc). METHODS: Sera from 68 patients with SSc were screened for ANCA by indirect immunofluorescence (IIF) assay and for antibodies to myeloperoxidase (MPO) by ELISA. All sera positive for ANCA on IIF were analyzed for reactivity against antigenic targets other than MPO [bactericidal/permeability-increasing protein (BPI), cathepsin G, lysozyme, elastase, PR3, and lactoferrin]. Twenty-three sera negative for ANCA were also tested for antibodies to BPI and cathepsin G using ELISA. RESULTS: The study included 33 patients with diffuse and 35 with limited SSc. ANCA was detected in 24 of the 68 sera (35.3%). In these 24 sera the antigenic targets were BPI in 14, cathepsin G in 13, and MPO in 8. Sera of 11 patients had reactivity against both BPI and cathepsin G. In sera, that were negative for ANCA, antibodies to BPI (4/23), cathepsin G (3/23), and MPO (1/44) were found in a small proportion of patients. Patients with antibodies to BPI had lower skin score, whereas no patient with antibodies to MPO had renal disease. CONCLUSION: BPI and cathepsin G are the major antigenic targets of ANCA seen in patients with SSc. Patients with antibodies to BPI had lower skin scores.     

Anemia and physical fitness of school children of rural Hyderabad

Physical fitness status of 119 school children was assessed by administering a simple field level 'running test' without any sophisticated equipment. Moderately anemic children had taken significantly longer time (6.25 min) to complete the 'running test' distance of 1.6 Km. Children with normal hemoglobin (Hb) values and those with higher level normal Hb values took shorter times (7.42 and 7.06 min) to complete the test distance. Deficits of weight for age, height for age and weight for height did not exert independent influence on the 'running time'. Anemic children in the sub-groups of each category of nutritional anthropometric indicator, performed poorly. Anemia proved to be a handicap either in the presence or absence of anthropometric deficits. Mild and moderate anemia imposed handicaps on physical endurance and fitness of school children irrespective of other nutritional deficits.     

Th-17 associated cytokines in patients with reactive arthritis/undifferentiated spondyloarthropathy

We and others have previously shown that IL-17 is elevated in the synovial fluid of patients with reactive arthritis (ReA)/undifferentiated spondyloarthropathy (uSpA) having acute synovitis. Major source for IL-17 is Th17 cells, which differentiate from Th0 cells under the influence of TGF-β and IL-6, IL1-β and are maintained by IL-21 and 23. There is a paucity of data on these cytokines in ReA/uSpA. Thus, we measured the levels of Th-17 differentiating and maintaining cytokines in synovial fluid of patients with ReA and uSpA. Fifty patients with ReA/uSpA (ReA 24, uSpA 26), 19 patients with rheumatoid arthritis (RA) and 11 patients with osteoarthritis (OA) were included in the study. Synovial fluid (SF) were collected from knee joint and stored at −80°C until analysis. Cytokines were assayed using ELISA in SF specimens. The median IL-17A levels were significantly elevated in ReA (48.3 pg/ml) and uSpA (32.5 pg/ml) as compared to non-inflammatory OA controls (<7.8 pg/ml; p < 0.0001), while comparable to RA (57.9 pg/ml). Further, IL-6 median values were higher in ReA (25.2 ng/ml) and uSpA (13.6 ng/ml) as compared to OA (0.76 ng/ml; p < 0.0001), and comparable to RA (15.8 ng/ml). The median levels of IL-1β, IL-21 levels were elevated in ReA, uSpA and RA as compared to OA but were not statistically significant. TGF-β levels in ReA and uSpA were similar to OA but lower than in RA (4340 pg/ml; p < 0.05). IL-23 was not detectable in any synovial fluid sample. However, levels of these cytokines did not correlate with disease activity parameters. Significant positive correlation was observed between IL-17 and IL-1β (r = 0.38, p < 0.005), IL-17 and IL-6 (r = 0.659, p < 0.0001), and IL-1β and IL-6 (r = 0.391, p < 0.0001) in ReA and uSpA group. Inflammatory synovitis in ReA/uSpA is mediated by pro-inflammatory cytokines like IL-17, IL-6, IL-1β, and IL-21. However, IL-23 was not detectable in SF. Good correlation between IL-17, IL-6, and IL 1β suggest that either they are co-regulated or they regulate each other.     

Takayasu arteritis: A distinct syndrome of large vessel vasculitis: A view point by late Professor Paul Bacon

Takayasu arteritis (TA), despite being classified as a large vessel vasculitis, has distinct genetic, pathological and clinical features as compared to giant cell arteritis. It is a rare disease seen more commonly in Asian countries. The challenge lies in assessing the degree of inflammation in a narrowed vessel and immunosuppressive therapy improves inflammatory features but is unable to open up an occluded vessel. It may have a positive effect on retarding further occlusion. Like antineutrophil cytoplasmic antibody‐associated vasculitis, TA needs a collaborative effort to do randomized controlled therapy to provide benefit to patients.