Transcriptional and Linkage Analyses Identify Loci that Mediate the Differential Macrophage Response to Inflammatory Stimuli and Infection

Macrophages display flexible activation states that range between pro-inflammatory (classical activation) and anti-inflammatory (alternative activation). These macrophage polarization states contribute to a variety of organismal phenotypes such as tissue remodeling and susceptibility to infectious and inflammatory diseases. Several macrophage- or immune-related genes have been shown to modulate infectious and inflammatory disease pathogenesis. However, the potential role that differences in macrophage activation phenotypes play in modulating differences in susceptibility to infectious and inflammatory disease is just emerging. We integrated transcriptional profiling and linkage analyses to determine the genetic basis for the differential murine macrophage response to inflammatory stimuli and to infection with the obligate intracellular parasite Toxoplasma gondii. We show that specific transcriptional programs, defined by distinct genomic loci, modulate macrophage activation phenotypes. In addition, we show that the difference between AJ and C57BL/6J macrophages in controlling Toxoplasma growth after stimulation with interferon gamma and tumor necrosis factor alpha mapped to chromosome 3, proximal to the Guanylate binding protein (Gbp) locus that is known to modulate the murine macrophage response to Toxoplasma. Using an shRNA-knockdown strategy, we show that the transcript levels of an RNA helicase, Ddx1, regulates strain differences in the amount of nitric oxide produced by macrophage after stimulation with interferon gamma and tumor necrosis factor. Our results provide a template for discovering candidate genes that modulate macrophage-mediated complex traits

Congenital localized scleroderma

OBJECTIVES: Juvenile localized scleroderma (JLS) usually has its onset during later childhood. This report describes the clinical and serologic features of six children with congenital localized scleroderma (CLS). STUDY DESIGN: A large, multinational study was conducted among pediatric rheumatology and dermatology centers by collecting information on demographics, family history, triggering environmental factors, clinical features, laboratory reports, and treatment of patients with JLS. Patients with onset at birth were carefully examined. RESULTS: Among 750 patients with JLS, 6 patients (0.8%) had scleroderma-related lesions at birth. Female-to-male ratio was 2:1. All patients had linear scleroderma, in four involving the face with en coup de sabre appearance. Two patients were misdiagnosed as having skin infection, one nevus, one salmon patch, and two undefined skin lesions. The mean diagnostic delay was 3.9 years. In comparison with the group of 733 patients with late-onset JLS, CLS presented a significantly more prolonged disease duration at diagnosis and a higher frequency of en coup de sabre subtypes. CONCLUSIONS: Congenital localized scleroderma is a rare and probably underestimated condition in neonates. The linear subtype was the exclusive manifestation of the disease. CLS should be included in the differential diagnosis of infants with cutaneous erythematous fibrotic lesions to avoid functional and aesthetic sequelae and to allow prompt therapy

Juvenile localized scleroderma: clinical and epidemiological features in 750 children. An international study

Juvenile localized scleroderma (JLS) includes a number of conditions often grouped together. With the long-term goal of developing uniform classification criteria, we studied the epidemiological, clinical and immunological features of children with JLS followed by paediatric rheumatology and dermatology centres. Methods. A large, multicentre, multinational study was conducted by collecting information on the demographics, family history, triggering environmental factors, clinical and laboratory features, and treatment of patients with JLS. Results. Seven hundred and fifty patients with JLS from 70 centres were enrolled into the study. The disease duration at diagnosis was 18 months. Linear scleroderma (LS) was the most frequent subtype (65%), followed by plaque morphea (PM) (26%), generalized morphea (GM) (7%) and deep morphea (DM) (2%). As many as 15% of patients had a mixed subtype. Ninety-one patients (12%) had a positive family history for rheumatic or autoimmune diseases; 100 (13.3%) reported environmental events as possible trigger. ANA was positive in 42.3% of the patients, with a higher prevalence in the LS-DM subtype than in the PM-GM subtype. Scl70 was detected in the sera of 3% of the patients, anticentromere antibody in 2%, anti-double-stranded DNA in 4%, anti-cardiolipin antibody in 13% and rheumatoid factor in 16%. Methotrexate was the drug most frequently used, especially during the last 5 yr. Conclusion. This study represents the largest collection of patients with JLS ever reported. The insidious onset of the disease, the delay in diagnosis, the recognition of mixed subtype and the better definition of the other subtypes should influence our efforts in educating trainees and practitioners and help in developing a comprehensive classification system for this syndrome