IgM, IgG, and IgA anti-DNA topoisomerase I antibodies in systemic sclerosis.

BACKGROUND: Anti-DNA topoisomerase I (anti-topo I) antibodies have been broadly studied in systemic sclerosis (SSc). The use of different native and molecularly cloned antigens has shown a predominant IgG response, and a variable frequency of positive IgM and IgA tests. We report herein the serological findings of SSc using a recombinant topo I obtained through a standard bacterial system. METHODS: Anti-topo I antibodies were studied in 45 SSc patients and 85 healthy controls through ELISA and western blot. Escherichia coli XL1-blue strain and pT7-7 vector were used to amplify a DNA topo I cDNA clone, and to obtain the recombinant polypeptide. The latter was purified by affinity chromatography, and the enzymatic and antigenic properties were evaluated through specific tests. A native antigen was included for comparison. RESULTS: The SSc group disclosed positive IgM (20%), IgG (86.6%), and IgA (26.6%) anti-topo I tests with the recombinant polypeptide, and a purified calf thymus antigen yielded similar results. IgG autoantibodies were frequently associated with skin involvement, esophageal dysfunction, and restrictive lung disease. The recombinant protein showed a molecular weight of 86.6 kDa, a positive topo I activity using a supercoiled pBR322 DNA relaxation test, and its carboxyl terminus region was recognized by specific antibodies. CONCLUSION: This report confirms that different immunoglobulin classes with anti-topo I activity may occur in SSc. IgG was the predominant serological feature with both, the recombinant and native antigens. The study also demonstrates the association between high levels of these autoantibodies and some clinical manifestations of SSc.

Correlacion entre los niveles de citoquinas en el lavado broncoalveolar en una cohorte de pacientes del Hospital Militar Central con esclerosis sistemica (SS), con y sin alveolitis / Cytokines in bronchoalveolar lavage in systemic sclerosis patient

Debido a la preocupación que produce la osteomielitis crónica y los problemas sociales y laborales que conlleva esta enfermedad, nos propusimos sacar adelante un protocolo de tratamiento médico-ortopédico que hemos implementando y desarrollado con la colaboración del Dr. Cesar Arango (Medico Infectólogo) en nuestros pacientes durante 20 años. Hemos utilizado esta metodología en 180 pacientes, 100 de sexo masculino y 80 de sexo femenino. Los segmentos anatómicos afectados fueron: tibia 56 por ciento, fémur 33 por ciento, antebrazo 6 por ciento, pie 4 por ciento y dedos de pie 1 por ciento. La base fundamental del tratamiento es el desbridamiento seriado de las lesiones con el paciente hospitalizado, la toma de cuatro cultivos en la primera intervención, la administración de antibióticos se lleva a cabo de acuerdo a determinación del medico infectólogo que se modifica según el resultado de los cultivos, y el cuidado postoperatorio domiciliario hasta obtener una granulación adecuada de las zonas desbridadas con cultivos negativos. Se rellena el espacio vado producido por los desbridamientos con injertos óseos extraídos de las espinas ilíacas provista la estabilización de la fractura. De estos 180 pacientes, el 97 por ciento se encuentra hasta el momento libre de recidivas, 5 pacientes no cumplieron con las expectativas del tratamiento y 1 paciente fue amputado. Consideramos que esta forma de tratamiento es adecuada para nuestro medio y mejora el pronóstico de los pacientes que sufren esta penosa enfermedad

Neuron specific enolase concentration is increased in serum and decreased in platelets of patients with active systemic sclerosis.

OBJECTIVE: To determine frequency, origin, and clinical associations of elevated serum neuron specific enolase (NSE) in systemic sclerosis (SSc). METHODS: Serum was obtained from 75 patients with SSc, 20 systemic lupus erythematosus, 8 polymyositis, 10 idiopathic interstitial lung disease, and 10 healthy volunteers. NSE status was determined in serum (in all individuals) and in platelet lysate (in volunteers and 30 patients with SSc). RESULTS: Elevated serum NSE (mean 22.6 ng/ml, range 12.1-68.2 ng/ml) was observed in 26 patients with SSc (34.6%). Those with diffuse SSc had higher serum NSE than those with limited disease (16.5 +/- 13.4 vs 9.6 +/- 5.0 ng/ml, p = 0.006). No association was found between serum NSE and lung or esophagus involvement. Patients with long-standing disease had lower serum NSE than those with early disease (10.8 +/- 7.3 vs 16.1 +/- 13.6 ng/ml, p = 0.05). Serum NSE was 19.4 +/- 13.0 ng/ml in patients with total skin score (TSS) > 20, 8.3 +/- 2.1 ng/ml in patients with TSS < 5, and 6.0 +/- 3.1 ng/ml in volunteers (p = 0.01). NSE platelet lysate concentration was 3.6 +/- 2.9 ng/ml in patients with TSS > 20, 12.4 +/- 4.1 ng/ml in those with TSS < 5, and 14.1 +/- 6.5 ng/ml in healthy individuals (p < 0.001). Volunteers and SSc patients with low TSS had comparable S/PL-NSE index (serum/platelet lysate NSE concentration) (0.42 +/- 0.16 and 0.75 +/- 0.33, respectively), both lower than SSc patients with high TSS (7.45 +/- 5.57) (p < 0.001). CONCLUSION: Elevated serum NSE was observed in one-third of SSc patients but not in other autoimmune rheumatic diseases. The inverse relationship between serum and platelet lysate NSE concentration suggests platelet activation as the origin of high serum NSE in SSc. NSE S/PL was the best discriminatory variable between healthy volunteers and SSc patients as well as between patients with high and low TSS. High serum NSE and high NSE-S/PL index seemed to be associated with SSc disease activity. Further work is warranted to investigate a possible role for this marker in assessing disease activity and therapy response.

The expression and localization of Scl-70/DNA topoisomerase I vary throughout the cell cycle.

PURPOSE AND METHODS: We investigated the expression and localization of topoisomerase I by Western blot and indirect fluorescent antibody assay, respectively, using anti-Scl-70/topo I from patients with diffuse scleroderma. The contribution of topoisomerase I to DNA replication was assessed using cells treated with the topoisomerase I inhibitor camptothecin. RESULTS: Scl-topo I was detected at all cell cycle phases as a single immunoreactive band of 100 kDa. Extracts from cells in the S phase contained the largest amount of immunoreactive Scl-70/topo I. Variations in the subcellular distribution of Scl-70/topo I were seen throughout the cell cycle, with a speckled nucleoplasmic distribution during G1 contrasting with concentration within the nucleolus during S. Camptothecin exposure blocked topoisomerase I expression and caused a significant decrease in DNA production. CONCLUSION: These data suggest (1) that topomerase I is active mainly during the S phase and contributes to DNA replication, and (2) that topoisomerase I may be involved in ribosomal gene transcription.