Rheumatoid Arthritis: Grom AA

Ramanan AV, Grom AA. · Department of Paediatric Rheumatology, North Bristol NHS Trust & Royal National Hospital for Rheumatic Diseases, Bath, UK. · Rheumatology (Oxford). · Pubmed #15956091 links to  free full text

Abstract: 'Science is the systematic classification of experience' George Henry Lewes (1817-78), English philosopher, critic, dramatist, scientist. Juvenile idiopathic arthritis (JIA) is prevalent in about 1 in 1000 children. The earliest formal description of this disease was by Sir George Frederick Still in 1897. This work was done when he was a registrar at the Hospital for Sick Children, Great Ormond Street, London. In this initial description of 19 patients he identified three patterns of arthritis, one of which came to be known later as Still's disease [now known as systemic-onset juvenile idiopathic arthritis (SoJIA)]. Over the next few decades it came to be appreciated that one form of arthritis in children is very different and dominated by the presence of systemic manifestations. Over the last two decades several paediatric rheumatologists have come together to classify juvenile arthritis for purposes of better disease identification and research. All along, the systemic form of juvenile arthritis was always recognized as belonging to a distinct group; in fact for several decades (and even now in some countries) the systemic form of juvenile arthritis was referred to as Still's disease. In this article we will attempt to highlight the reasons why we feel that SoJIA is perhaps not best retained in the company of JIA.

Grom AA. · Division of Rheumatology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45215, USA. · Arthritis Rheum. · Pubmed #15022306 links to  free full text

This publication has no abstract.

Grom AA. · Cincinnati Children's Hospital Medical Center, OH 45215, USA. · Curr Opin Rheumatol. · Pubmed #12960485 No free full text.

Abstract: PURPOSE OF THE REVIEW: One of the most perplexing features of systemic-onset juvenile rheumatoid arthritis is the association with macrophage activation syndrome, a life-threatening complication caused by excessive activation and proliferation of T cells and macrophages. The main purpose of the review is to summarize current understanding of the relation between macrophage activation syndrome and other clinically similar hemophagocytic disorders. RECENT FINDINGS: Clinically, macrophage activation syndrome has strong similarities with familial and virus-associated reactive hemophagocytic lymphohistiocytosis. The better understood familial hemophagocytic lymphohistiocytosis is a constellation of rare, autosomal recessive immune disorders. The most consistent immunologic abnormalities in patients with familial hemophagocytic lymphohistiocytosis are decreased natural killer and cytotoxic cell functions. In approximately one third of familial hemophagocytic lymphohistiocytosis patients, these immunologic abnormalities are secondary to mutations in the gene encoding perforin, a protein that mediates cytotoxic activity of natural killer and cytotoxic CD8+ T cells. Several recent studies have suggested that profoundly depressed natural killer cell activity and abnormal levels of perforin expression may be a feature of macrophage activation syndrome in systemic-onset juvenile rheumatoid arthritis as well. Although it has been proposed that in both hemophagocytic lymphohistiocytosis and macrophage activation syndrome, natural killer and cytotoxic cell dysfunction may lead to inadequate control of cellular immune responses, the exact nature of such dysregulation and the relation between macrophage activation syndrome and hemophagocytic lymphohistiocytosis still remain to be determined.

Grom AA, Hirsch R. · William S. Rowe Division of Rheumatology, Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Curr Opin Rheumatol. · Pubmed #10990179 No free full text.

Abstract: Several lines of indirect evidence suggest that the pathologic autoimmune responses in juvenile rheumatoid arthritis may be antigen-driven and T cell-mediated. These include (1) activation markers expressed on synovial T cells suggestive of previous activation in vivo; (2) persistent oligoclonally expanded T-cell populations accumulating preferentially in the synovial compartment; (3) some T-cell receptor complementarity-determining region 3 sequence similarities between different clones in an individual patient; and (4) T-cell derived cytokines of predominantly Th1 type. Whether T-cell contribution is limited to only early stages of the disease (as appears to be the case in collagen-induced arthritis) or T cells are required for the perpetuation of the inflammation at later stages as well, still remains to be determined.

Barnes MG, Grom AA, Thompson SD, Griffin TA, Pavlidis P, Itert L, Fall N, Sowders DP, Hinze CH, Aronow BJ, Luyrink LK, Srivastava S, Ilowite NT, Gottlieb BS, Olson JC, Sherry DD, Glass DN, Colbert RA. · Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio. · Arthritis Rheum. · Pubmed #19565513 No free full text.

Abstract: OBJECTIVE: To identify differences in peripheral blood gene expression between patients with different subclasses of juvenile idiopathic arthritis (JIA) and healthy controls in a multicenter study of patients with recent-onset JIA prior to treatment with disease-modifying antirheumatic drugs (DMARDs) or biologic agents. METHODS: Peripheral blood mononuclear cells (PBMCs) from 59 healthy children and 136 patients with JIA (28 with enthesitis-related arthritis [ERA], 42 with persistent oligoarthritis, 45 with rheumatoid factor [RF]-negative polyarthritis, and 21 with systemic disease) were isolated from whole blood. Poly(A) RNA was labeled using a commercial RNA amplification and labeling system (NuGEN Ovation), and gene expression profiles were obtained using commercial expression microarrays (Affymetrix HG-U133 Plus 2.0). RESULTS: A total of 9,501 differentially expressed probe sets were identified among the JIA subtypes and controls (by analysis of variance; false discovery rate 5%). Specifically, 193, 1,036, 873, and 7,595 probe sets were different in PBMCs from the controls compared with those from the ERA, persistent oligoarthritis, RF-negative polyarthritis, and systemic JIA patients, respectively. In patients with persistent oligoarthritis, RF-negative polyarthritis, and systemic JIA subtypes, up-regulation of genes associated with interleukin-10 (IL-10) signaling was prominent. A hemoglobin cluster was identified that was underexpressed in ERA patients but overexpressed in systemic JIA patients. The influence of JAK/STAT, ERK/MAPK, IL-2, and B cell receptor signaling pathways was evident in patients with persistent oligoarthritis. In systemic JIA, up-regulation of innate immune pathways, including IL-6, Toll-like receptor/IL-1 receptor, and peroxisome proliferator-activated receptor signaling, were noted, along with down-regulation of gene networks related to natural killer cells and T cells. Complement and coagulation pathways were up-regulated in systemic JIA, with a subset of these genes being differentially expressed in other subtypes as well. CONCLUSION: Expression analysis identified differentially expressed genes in PBMCs obtained early in the disease from patients with different subtypes of JIA and in healthy controls, providing evidence of immunobiologic differences between these forms of childhood arthritis.

Shishov M, Henrickson M, Burgos-Vargas R, Rubio-Pérez N, Baca V, Romero-Feregrino R, Solís-Vallejo E, Huang B, Grom AA, Lovell DJ. · Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA. · Clin Exp Rheumatol. · Pubmed #18173929 No free full text.

Abstract: OBJECTIVE: To investigate if the persistence of systemic features is longer in Hispanic children with systemic juvenile idiopathic arthritis (S-JIA) than in non-Hispanic children with S-JIA and to determine early predictors of systemic and articular disease. METHODS: We performed a multi-center retrospective chart review of patients followed in six pediatric rheumatology centers with onset of S-JIA from 1974 to 2004. Patients were included in the study if they had been followed for > or = 1 year after disease onset. Information collected included demographic, clinical, laboratory and treatment data. Systemic features included fever, rash, lymphadenopathy, hepatosplenomegaly, pericarditis, and pleuritis. RESULTS: Of the 159 S-JIA patients screened, 120 (75%) met our inclusion criteria. There were 65 boys and 55 girls. The mean follow-up period for Hispanic patients was 5.7 years (SD 4.0) and for non-Hispanic patients was 8.6 years (SD 7.2). There was no significant difference in the presence of systemic features between Hispanic and non-Hispanic patients at 0.5, 1, 2, 4, 6, 8, and 10 years of follow-up. Polyarthritis at the 6-month visit was predictive of systemic features (OR 9.7, 95% CI 1.16-81.35, p = 0.036) and polyarthritis (OR 5.6, 95% CI 1.42-21.8, p = 0.014) at last follow-up. CONCLUSION: In children with S-JIA, Hispanics did not demonstrate longer persistence of systemic features than non-Hispanics. Polyarthritis at 6 months strongly predicted the development of persistent systemic features and chronic polyarticular disease.

Fall N, Barnes M, Thornton S, Luyrink L, Olson J, Ilowite NT, Gottlieb BS, Griffin T, Sherry DD, Thompson S, Glass DN, Colbert RA, Grom AA. · Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Arthritis Rheum. · Pubmed #17968951 links to  free full text

Abstract: OBJECTIVE: Systemic juvenile idiopathic arthritis (JIA) is frequently associated with the development of macrophage activation syndrome. This study was undertaken to better understand the relationship between systemic JIA and macrophage activation syndrome. METHODS: Gene expression profiles were examined in 17 patients with untreated new-onset systemic JIA, 5 of whom showed evidence of subclinical macrophage activation syndrome (of whom 2 eventually developed overt macrophage activation syndrome). Peripheral blood mononuclear cells (PBMCs) were separated on Ficoll gradients, and purified RNA was analyzed using Affymetrix GeneChip expression arrays. A fraction of the PBMCs were used for flow cytometry to define the cellular composition of the samples. RESULTS: Two hundred twenty-five differentially expressed genes (P < 0.05) that distinguished patients with systemic JIA from healthy controls (n = 30) were identified. Clustering analysis indicated that expression patterns correlated with serum ferritin levels. Three main clusters distinguished systemic JIA patients with highly elevated ferritin levels (including those with subclinical macrophage activation syndrome) from those with normal or only moderately elevated ferritin levels. The first cluster comprised genes involved in the synthesis of hemoglobins and structural proteins of erythrocytes. This transcriptional profile was consistent with immature nucleated red blood cells, likely reflective of high red blood cell turnover. Also included were transcripts indicating immature granulocytes. The second cluster was enriched for genes involved in cell cycle regulation. The third cluster was enriched for genes involved in innate immune responses, including those involved in the negative regulation of Toll-like receptor/interleukin-1 receptor-triggered inflammatory cascades and markers of the alternative pathway of macrophage differentiation. Additional differentially expressed genes of interest were those involved in the cytolytic pathway, including SH2D1A and Rab27a. CONCLUSION: These data indicate that gene expression profiling can be a useful tool for identifying early macrophage activation syndrome in patients with systemic JIA.

Bleesing J, Prada A, Siegel DM, Villanueva J, Olson J, Ilowite NT, Brunner HI, Griffin T, Graham TB, Sherry DD, Passo MH, Ramanan AV, Filipovich A, Grom AA. · Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Arthritis Rheum. · Pubmed #17328073 links to  free full text

Abstract: OBJECTIVE: Macrophage activation syndrome is characterized by an overwhelming inflammatory reaction driven by excessive expansion of T cells and hemophagocytic macrophages. Levels of soluble interleukin-2 receptor alpha (sIL-2Ralpha) and soluble CD163 (sCD163) may reflect the degree of activation and expansion of T cells and macrophages, respectively. This study was undertaken to assess the value of serum sIL-2Ralpha and sCD163 in diagnosing acute macrophage activation syndrome complicating systemic juvenile idiopathic arthritis (JIA). METHODS: Enzyme-linked immunosorbent assay was used to assess sIL-2Ralpha and sCD163 levels in sera from 7 patients with acute macrophage activation syndrome complicating systemic JIA and 16 patients with untreated new-onset systemic JIA. The results were correlated with clinical features of established macrophage activation syndrome, including ferritin levels. RESULTS: The median level of sIL-2Ralpha in the patients with macrophage activation syndrome was 19,646 pg/ml (interquartile range [IQR] 18,128), compared with 3,787 pg/ml (IQR 3,762) in patients with systemic JIA (P = 0.003). Similarly, the median level of sCD163 in patients with macrophage activation syndrome was 23,000 ng/ml (IQR 14,191), compared with 5,480 ng/ml (IQR 2,635) in patients with systemic JIA (P = 0.017). In 5 of 16 patients with systemic JIA, serum levels of sIL-2Ralpha or sCD163 were comparable with those in patients with acute macrophage activation syndrome. These patients had high inflammatory activity associated with a trend toward lower hemoglobin levels (P = 0.11), lower platelet counts, and significantly higher ferritin levels (P = 0.02). Two of these 5 patients developed overt macrophage activation syndrome several months later. CONCLUSION: Levels of sIL-2Ralpha and sCD163 are promising diagnostic markers for macrophage activation syndrome. They may also help identify patients with subclinical macrophage activation syndrome.

Fall N, Bove KE, Stringer K, Lovell DJ, Brunner HI, Weiss J, Higgins GC, Bowyer SL, Graham TB, Thornton S, Grom AA. · Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Arthritis Rheum. · Pubmed #16200621 links to  free full text

Abstract: OBJECTIVE: To investigate the relationship between the vasculopathy of juvenile dermatomyositis (juvenile DM) and the balance between the angiostatic ELR- and angiogenic ELR+ CXC chemokines in the muscle of patients with the disease. METHODS: The expression of 3 ELR- CXC chemokines (interferon-inducible protein 10 [IP-10], monokine induced by interferon-gamma, and interferon-inducible T cell alpha-chemoattractant) and 2 ELR+ CXC chemokines was quantitated in muscle biopsy samples from 7 patients with juvenile DM and 7 healthy children, by real-time polymerase chain reaction. The findings were correlated with various histopathologic features, with particular emphasis on the degree of vasculopathy. Synovial biopsy specimens from patients with juvenile rheumatoid arthritis (JRA) were used for additional comparison. RESULTS: The angiostatic ELR- chemokines were expressed at high levels, while the angiogenic ELR+ chemokines were barely detectable, in most juvenile DM samples. This contrasted sharply with the findings in both normal muscle biopsy specimens and JRA synovial tissue specimens. The expression of the ELR- chemokines in juvenile DM samples correlated with the intensity of mononuclear cell infiltration. Furthermore, the juvenile DM samples with the highest degree of capillary loss had the highest levels of ELR- CXC chemokines. The presence of IP-10 in juvenile DM muscle specimens was confirmed by immunohistochemistry analysis. In addition, immunohistochemical staining of muscle tissue revealed that CXCR3, a receptor utilized by ELR- CXC chemokines, was expressed in vascular endothelial cells. CONCLUSION: Increased expression of the interferon-induced angiostatic ELR- CXC chemokines is a feature of juvenile DM that parallels the degree of vasculopathy in patients with the disease. Collectively, these findings are consistent with a model in which a subset of inflammatory cells secrete angiostatic ligands, which then contribute to a local atrophying effect on the muscle's vasculature via a receptor-mediated process.

Villanueva J, Lee S, Giannini EH, Graham TB, Passo MH, Filipovich A, Grom AA. · 1Division of Hematology/Oncology, Children's Hospital Medical Center, Cincinnati, Ohio, USA. · Arthritis Res Ther. · Pubmed #15642140 links to  free full text

Abstract: Macrophage activation syndrome (MAS) has been reported in association with many rheumatic diseases, most commonly in systemic juvenile rheumatoid arthritis (sJRA). Clinically, MAS is similar to hemophagocytic lymphohistiocytosis (HLH), a genetic disorder with absent or depressed natural killer (NK) function. We have previously reported that, as in HLH, patients with MAS have profoundly decreased NK activity, suggesting that this abnormality might be relevant to the pathogenesis of the syndrome. Here we examined the extent of NK dysfunction across the spectrum of diseases that comprise juvenile rheumatoid arthritis (JRA). Peripheral blood mononuclear cells (PBMC) were collected from patients with pauciarticular (n = 4), polyarticular (n = 16), and systemic (n = 20) forms of JRA. NK cytolytic activity was measured after co-incubation of PBMC with the NK-sensitive K562 cell line. NK cells (CD56+/T cell receptor [TCR]-alphabeta-), NK T cells (CD56+/TCR-alphabeta+), and CD8+ T cells were also assessed for perforin and granzyme B expression by flow cytometry. Overall, NK cytolytic activity was significantly lower in patients with sJRA than in other JRA patients and controls. In a subgroup of patients with predominantly sJRA, NK cell activity was profoundly decreased: in 10 of 20 patients with sJRA and in only 1 of 20 patients with other JRA, levels of NK activity were below two standard deviations of pediatric controls (P = 0.002). Some decrease in perforin expression in NK cells and cytotoxic T lymphocytes was seen in patients within each of the JRA groups with no statistically significant differences. There was a profound decrease in the proportion of circulating CD56bright NK cells in three sJRA patients, a pattern similar to that previously observed in MAS and HLH. In conclusion, a subgroup of patients with JRA who have not yet had an episode of MAS showed decreased NK function and an absence of circulating CD56bright population, similar to the abnormalities observed in patients with MAS and HLH. This phenomenon was particularly common in the systemic form of JRA, a clinical entity strongly associated with MAS.

Barron AC, Lee TL, Taylor J, Moore T, Passo MH, Graham TB, Griffin TA, Grom AA, Lovell DJ, Brunner HI. · Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229-3039, USA. · Arthritis Rheum. · Pubmed #15593249 links to  free full text

Abstract: OBJECTIVE: To assess the feasibility and construct validity of the willingness-to-pay (WTP) technique for measuring health care preferences in families of children with juvenile idiopathic arthritis (JIA). METHODS: Parents were asked to estimate the monthly US dollar amount they would be willing to pay to obtain for their child the following hypothetical drugs: ARTHRO, which guarantees complete clinical response; and NO-STOM-ACHE, a drug that eliminates gastrointestinal (GI) symptoms. A yes/no question was used with random assignment of the starting bids. Parents who agreed to pay the starting bid were then asked whether they would be willing to pay 200% and then 400% of this initial bid. Socioeconomic data and information on medications, disease activity, patient physical function, wellbeing, and health-related quality of life (HRQOL) were obtained. RESULTS: Sixty-two families of children with JIA were interviewed. GI symptoms were present in 54%, and 53% of the children had joints with active arthritis or limited range of motion. Four parents (7%) were unwilling to pay anything for any of the studied medications. The mean amount (median; mean percentage of available family income) families were willing to pay was $395 ($300; 15%) for ARTHRO and $109 ($80; 4%) for NO-STOM-ACHE. Correlation and regression analysis supported that, adjusted for the available family income, the WTP for ARTHRO was associated with disease activity, pain, and the HRQOL of the patients. After correction for the starting bids and the available family income, the WTP for NO-STOM-ACHE was associated with the patient's HRQOL, pain, and the amount of GI discomfort. CONCLUSION: The WTP technique is feasible and has construct validity for measuring health care preferences for children with JIA. Relatively large WTP estimates support a possible important negative impact of the disease on families of children with JIA.

Barnes MG, Aronow BJ, Luyrink LK, Moroldo MB, Pavlidis P, Passo MH, Grom AA, Hirsch R, Giannini EH, Colbert RA, Glass DN, Thompson SD. · William S. Rowe Division of Rheumatology, Cincinnati Children's Hospital Medical Center, OH 45229, USA. · Rheumatology (Oxford). · Pubmed #15150433 links to  free full text

Abstract: OBJECTIVE: To evaluate the ability of microarray-based methods to identify genes with disease-specific expression patterns in peripheral blood mononuclear cells (PBMC) and synovial fluid mononuclear cells (SFMC) of juvenile arthritis patients and healthy controls. METHODS: Microarray data (Affymetrix U95Av2) from 26 PBMC and 20 SFMC samples collected from patients with active disease (classified by course according to ACR criteria) were analysed for expression patterns that correlated with disease characteristics. For comparison, PBMC gene expression profiles were obtained from 15 healthy controls. Real-time PCR was used for confirmation of gene expression differences. RESULTS: Statistical analysis of gene expression patterns in PBMC identified 378 probe sets corresponding to 342 unique genes with differing expression levels between polyarticular course patients and controls (t test, P<0.0001). The genes represented by these probe sets were enriched for functions related to regulation of immune cell functions, receptor signalling as well as protein metabolism and degradation. Included in these probe sets were a group of CXCL chemokines with functions related to angiogenesis. Further analysis showed that, whereas angiogenic CXCL (ELR+) gene expression was elevated in polyarticular PBMC, expression of angiostatic CXCL (ELR-) chemokines was lower in polyarticular SFMC compared with corresponding pauciarticular samples (t test, P<0.05). CONCLUSIONS: This pilot study demonstrates that juvenile arthritis patients exhibit complex patterns of gene expression in PBMC and SFMC. The presence of disease-correlated biologically relevant gene expression patterns suggests that the power of this approach will allow better understanding of disease mechanisms, identify distinct clinical phenotypes in disease subtypes, and suggest new therapeutic approaches.

Grom AA, Villanueva J, Lee S, Goldmuntz EA, Passo MH, Filipovich A. · William S. Rowe Division of Rheumatology, and the Division of Hematology/Oncology, Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · J Pediatr. · Pubmed #12640378 No free full text.

Abstract: OBJECTIVES: To assess natural killer (NK) and cytotoxic functions in patients with systemic-onset juvenile rheumatoid arthrithis (soJRA) complicated by macrophage activation syndrome (MAS). METHODS: NK cells (CD56+/TCRalphabeta-), NK T cells (CD56+/TCRalphabeta+) and CD8+ cells were assessed for perforin expression by flow cytometry. NK cytotoxic activity was measured after coincubation of mononuclear cells with an NK-sensitive K562 cell line. RESULTS: Two major patterns of immunologic abnormalities were detected. Four of 7 patients had decreased NK activity, low NK cell numbers, and mildly increased levels of perforin expression in CD8+ and CD56+ cytotoxic cells. Three remaining patients with MAS, however, had decreased NK activity associated with low levels of perforin expression in all cytotoxic cell populations, a pattern indistinguishable from that in carriers of perforin-deficient familial hemophagocytic lymphohistiocytosis. Remarkably, two of these patients had previous episodes of MAS. CONCLUSIONS: NK dysfunction is an immunologic abnormality common to both familial hemophagocytic lymphohistiocytosis and MAS of soJRA. The extent of NK cell abnormalities in soJRA needs to be further investigated.

Yang L, Thornton S, Grom AA. · Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Arthritis Rheum. · Pubmed #12428244 links to  free full text

Abstract: OBJECTIVE: One of the pathologic hallmarks of juvenile rheumatoid arthritis (JRA) is a tumor-like expansion of inflamed synovial tissue, or pannus, which causes much of the joint damage in this disease. The expansion of pannus is supported by extensive formation of new blood vessels. We have previously shown that revascularization of minced JRA synovial tissues engrafted into SCID mice correlated with the intensity of inflammatory activity in the tissues and with interleukin-15 (IL-15) expression. Since synovial vascular endothelial cells (VECs) expressed IL-15 receptors, the present study was undertaken to investigate the hypothesis that IL-15 might play a role in neovascularization of the pannus. METHODS: To evaluate IL-15 for possible angiogenic activity, we assessed the ability of recombinant human IL-15 (rHuIL-15) to induce VEC growth directly and to stimulate synovial cells to produce endothelial growth factors. Since IL-15 had been shown to inhibit apoptosis of certain immune cells, we were also interested in whether it might have similar effects on VECs. Apoptosis was induced by addition of sodium nitroprusside (SNP) at 1-2 mM to >80% confluent primary VECs, and numbers of apoptotic cells were determined by annexin V assay. RESULTS: Addition of rHuIL-15 at 10-100 ng/ml to primary synovial fibroblast cultures failed to up-regulate expression of vascular endothelial growth factor and angiopoietin 1 by these cells. Although rHuIL-15 failed to induce a mitogenic response of VECs, it promoted survival of these cells on Matrigel. Preincubation of VECs with rHuIL-15 at 50 ng/ml significantly reduced the proportion of VECs undergoing apoptosis. CONCLUSION: IL-15 promotes survival of VECs on Matrigel and inhibits SNP-induced apoptosis of endothelial cells. We hypothesize that this mechanism may be relevant to the stabilization of newly formed vascular structures in JRA synovium.

Scola MP, Thompson SD, Brunner HI, Tsoras MK, Witte D, Van Dijk MA, Grom AA, Passo MH, Glass DN. · Department of Pediatrics, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA. · J Rheumatol. · Pubmed #11838858 No free full text.

Abstract: OBJECTIVE: To compare synovial tissue cytokine mRNA expression between patients with juvenile rheumatoid arthritis (JRA) and a heterogeneous group of non-autoimmune arthropathies (controls) with respect to type 1/type 2 balance. METHODS: Thirty-five JRA (average 9.1 years' disease duration) and 13 control synovial tissues were studied. As a measure of the type 1/type 2 cytokine balance in a subset of the JRA and control tissues, interferon-gamma (IFN-gamma) and interleukin 4 (IL-4) mRNA levels were measured by competitive fragment reverse transcription-polymerase chain reaction. To quantitate additional cytokines relevant to this balance, multiprobe ribonuclease protection assays were employed measuring IL-5, IL-10, IL-13, IL-15, IL-18, and IL-12 (p35 and p40 subunits). Immunohistochemistry was performed on JRA tissues using antibodies specific for IL-15 and IL-18. RESULTS: A higher IFN-gamma:IL-4 ratio (p = 0.034) was found in JRA tissues compared to controls. JRA tissues also displayed higher mRNA levels of IL-12p35 (p = 0.021), IL-15 (p = 0.002), and IL-18 (p = 0.017), but not IL-4 and IL-10. IFN-gamma expression in JRA, but not controls, correlated strongly with IL-12p35 (r = 0.63) and IL-12p40 (r = 0.73) levels. A subset of IL-15+ and IL-18+ cells was detected in JRA synovial tissues, largely within perivascular aggregates. CONCLUSION: JRA synovial tissue cytokine expression patterns indicate a type 1 bias, even in the later stages of disease. The strong correlation between IFN-gamma and IL-12 in JRA suggests a prominent role for IL-12 in promoting the type I bias, while IL-15 and IL-18 may also indirectly increase IFN-gamma expression and further bias the immune response.

Prahalad S, Bove KE, Dickens D, Lovell DJ, Grom AA. · Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Ohio 45229-3039, USA. · J Rheumatol. · Pubmed #11550985 No free full text.

Abstract: Macrophage activation syndrome (MAS), a recognized complication of systemic juvenile rheumatoid arthritis (sJRA), has been associated with significant morbidity and mortality. Dysregulation of macrophage-lymphocyte interactions leading to uncontrolled proliferation of highly activated macrophages and massive release of proinflammatory cytokines including tumor necrosis factor-alpha (TNF-alpha) appears to be central to the pathogenesis of this syndrome. Until now the mainstay of therapy has been corticosteroids and cyclosporin A. We describe a patient with MAS and sJRA successfully treated with the anti-TNF agent etanercept. The outcome in this patient suggests etanercept might be an effective therapeutic agent in MAS.

Scola MP, Imagawa T, Boivin GP, Giannini EH, Glass DN, Hirsch R, Grom AA. · Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA. · Arthritis Rheum. · Pubmed #11315918 links to  free full text

Abstract: OBJECTIVE: Although increased vascularity was noted in early histopathologic studies of juvenile rheumatoid arthritis (JRA) synovium, the available data on angiogenesis in JRA are very limited. The main purposes of this study were to assess expression of the key angiogenic factors in JRA synovium, and to evaluate a SCID mouse model of JRA as an approach to study in vivo regulation of the expression of these factors in JRA. METHODS: RNase protection assay was used to assess the expression of the key angiogenic factors in fresh JRA synovium and in JRA synovial tissue fragments that had been minced and then implanted into SCID mice. Vascularity of the samples was assessed by immunohistochemical staining for von Willebrand factor. Synovial specimens obtained from patients with osteoarthritis (OA) or other noninflammatory arthropathies were used as controls. RESULTS: Detectable levels of messenger RNA for vascular endothelial growth factor and angiopoietin 1 and their respective receptors, as well as endoglin and thrombin receptors, were present in all JRA tissue specimens studied. The levels of expression of these factors in JRA tissues were significantly higher than those in tissues obtained from patients with OA or other noninflammatory arthropathies. Furthermore, increased expression of the key angiogenic factors in the fresh JRA tissues correlated with the exuberant revascularization of JRA minced tissue fragments implanted into SCID mice. This was in sharp contrast to the poor revascularization of implanted OA tissues. CONCLUSION: JRA synovium is characterized by high angiogenic activity. SCID mouse-human JRA synovium chimeras may provide a good approach to study the in vivo regulation of angiogenesis in JRA.