Sabine Berthier

Th1 and Th17 lymphocytes expressing CD161 are implicated in giant cell arteritis and polymyalgia rheumatica pathogenesis

OBJECTIVE Giant cell arteritis (GCA) is the most frequently occurring vasculitis in elderly individuals, and its pathogenesis is not fully understood. The objective of this study was to decipher the role of the major CD4+ T cell subsets in GCA and its rheumatologic form, polymyalgia rheumatica (PMR). METHODS A prospective study of the phenotype and the function of major CD4+ T cell subsets (Th1, Th17, and Treg cells) was performed in 34 untreated patients with GCA or PMR, in comparison with 31 healthy control subjects and with the 27 treated patients who remained after the 7 others withdrew. RESULTS Compared with control subjects, patients with GCA and patients with PMR had a decreased frequency of Treg cells and Th1 cells, whereas the percentage of Th17 cells was significantly increased. Furthermore, an analysis of temporal artery biopsy specimens obtained from patients affected by GCA for whom biopsy results were positive demonstrated massive infiltration by Th17 and Th1 lymphocytes without any Treg cells. After glucocorticoid treatment, the percentages of circulating Th1 and Th17 cells decreased, whereas no change in the Treg cell frequency was observed. The frequency of CD161+CD4+ T cells, which are considered to be Th17 cell precursors, was similar in patients and control subjects. However, these cells highly infiltrated GCA temporal artery biopsy specimens, and their ability to produce interleukin-17 in vitro was significantly enhanced in patients with GCA and patients with PMR and was correlated with a decrease in the phosphorylated form of STAT-1. CONCLUSION This study is the first to demonstrate that the frequency of Treg cells is decreased in patients with GCA and patients with PMR, and that CD161+CD4+ T lymphocytes, differentiated into Th1 cells and Th17 cells, are involved in the pathogenesis of GCA and PMR.

Immunologic effects of rituximab on the human spleen in immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease with a complex pathogenesis. As in many B cell-related autoimmune diseases, rituximab (RTX) has been shown to increase platelet counts in some ITP patients. From an immunologic standpoint, the mode of action of RTX and the reasons underlying its limited efficacy have yet to be elucidated. Because splenectomy is a cornerstone treatment of ITP, the immune effect of RTX on this major secondary lymphoid organ was investigated in 18 spleens removed from ITP patients who were treated or not with RTX. Spleens from ITP individuals had follicular hyperplasia consistent with secondary follicles. RTX therapy resulted in complete B-cell depletion in the blood and a significant reduction in splenic B cells, but these patients did not achieve remission. Moreover, whereas the percentage of circulating regulatory T cells (Tregs) was similar to that in controls, splenic Tregs were reduced in ITP patients. Interestingly, the ratio of proinflammatory Th1 cells to suppressive Tregs was increased in the spleens of patients who failed RTX therapy. These results indicate that although B cells are involved in ITP pathogenesis, RTX-induced total B-cell depletion is not correlated with its therapeutic effects, which suggests additional immune-mediated mechanisms of action of this drug.

Efficacy and tolerance of infliximab in refractory Takayasu arteritis: French multicentre study

OBJECTIVE To analyse the efficacy and tolerance of infliximab in refractory Takayasu arteritis (TA). METHODS French multicentre retrospective study that included patients with TA. Clinical disease activity was defined as new vascular and/or constitutional signs. RESULTS Fifteen patients with TA [median age 41 (range 17-61) years; 13 women] were included. At initiation of infliximab therapy, 14 patients were treated with CSs [prednisone; median dose 20 (range 5-35) mg/day], MTX (n = 7) or AZA (n = 4). Infliximab was used at median 5 (range 3-5) mg/kg at a median of every 6 (range 4-8) weeks. A partial or good overall response was noted in 13 (87%) of the 15 cases, 10 (77%) of the 13 cases and 8 (73%) of the 11 cases at 3, 6 and 12 months, respectively. Clinical and biological activities significantly decreased within 3 months (from 11 at baseline to 4 patients at 12 months; P < 0.05), and similarly for CS dose [from median 20 (range 5-35) mg/day at baseline to median 6 (range 2.5-30) mg/day at 12 months; P < 0.05]. Only one patient was still steroid-dependent at 12 months (vs 8 cases before infliximab). CRP regressed from a median 30 (range 4-70) mg/l to 5 (range 0-57) mg/l and 6 (0-50) mg/l at 3 and 6 months, respectively (P < 0.05). Side effects were two infusion-related reactions, one pulmonary tuberculosis, one severe bacterial infection and EBV reactivation. CONCLUSION This study confirms the interest of infliximab in terms of clinical and biological response, as well as the steroid-sparing effect in TA.

Efficacy of Biological-Targeted Treatments in Takayasu Arteritis Multicenter, Retrospective Study of 49 Patients

Background— The goal of this work was to assess the safety and efficacy of biologics (ie, tumor necrosis factor-&agr; antagonists and tocilizumab) in patients with Takayasu arteritis. Methods and Results— This was a retrospective, multicenter study of the characteristics and outcomes of 49 patients with Takayasu arteritis (80% female; median age, 42 years [20–55 years] treated by tumor necrosis factor-&agr; antagonists [80%] or tocilizumab [20%]) and fulfilling American College of Rheumatology or Ishikawa criteria. Factors associated with complete response were assessed. Eighty-eight percent of patients with Takayasu arteritis were inadequately controlled with or were intolerant to conventional immunosuppressive therapy (median number, 3 [1–5]). Overall response (ie, complete and partial) to biological-targeted treatments at 6 and 12 months was 75% and 83%, respectively. There were significantly lower C-reactive protein levels at the initiation of biological-targeted treatments (22 mg/L [10–46 mg/L] versus 58 mg/L [26–76 mg/L]; P=0.006) and a trend toward fewer immunosuppressants drugs used before biologics (P=0.054) in responders (ie, complete or partial responders) relative to nonresponders to biological-targeted treatments. C-reactive protein levels and daily prednisone dose significantly decreased after 12 months of biological-targeted treatments (30 versus 6 mg/L [P<0.05] and 15 versus 7.5 mg [P<0.05] at baseline and 12 months, respectively). The 3-year relapse-free survival was 90.9% (83.5%–99%) over the biological treatment period compared with 58.7% (43.3%–79.7%; P=0.0025) with disease-modifying antirheumatic drugs. No difference in efficacy was found between tumor necrosis factor-&agr; antagonists and tocilizumab. After a median follow-up of 24 months (2–95 months), 21% of patients experienced adverse effects, with biological-targeted treatments discontinued in 6.6% of cases. Conclusion— This nationwide study shows a high efficacy of biological-targeted treatments in refractory patients with Takayasu arteritis with an acceptable safety profile.Background— The goal of this work was to assess the safety and efficacy of biologics (ie, tumor necrosis factor-α antagonists and tocilizumab) in patients with Takayasu arteritis. Methods and Results— This was a retrospective, multicenter study of the characteristics and outcomes of 49 patients with Takayasu arteritis (80% female; median age, 42 years [20–55 years] treated by tumor necrosis factor-α antagonists [80%] or tocilizumab [20%]) and fulfilling American College of Rheumatology or Ishikawa criteria. Factors associated with complete response were assessed. Eighty-eight percent of patients with Takayasu arteritis were inadequately controlled with or were intolerant to conventional immunosuppressive therapy (median number, 3 [1–5]). Overall response (ie, complete and partial) to biological-targeted treatments at 6 and 12 months was 75% and 83%, respectively. There were significantly lower C-reactive protein levels at the initiation of biological-targeted treatments (22 mg/L [10–46 mg/L] versus 58 mg/L [26–76 mg/L]; P =0.006) and a trend toward fewer immunosuppressants drugs used before biologics ( P =0.054) in responders (ie, complete or partial responders) relative to nonresponders to biological-targeted treatments. C-reactive protein levels and daily prednisone dose significantly decreased after 12 months of biological-targeted treatments (30 versus 6 mg/L [ P <0.05] and 15 versus 7.5 mg [ P <0.05] at baseline and 12 months, respectively). The 3-year relapse-free survival was 90.9% (83.5%–99%) over the biological treatment period compared with 58.7% (43.3%–79.7%; P =0.0025) with disease-modifying antirheumatic drugs. No difference in efficacy was found between tumor necrosis factor-α antagonists and tocilizumab. After a median follow-up of 24 months (2–95 months), 21% of patients experienced adverse effects, with biological-targeted treatments discontinued in 6.6% of cases. Conclusion— This nationwide study shows a high efficacy of biological-targeted treatments in refractory patients with Takayasu arteritis with an acceptable safety profile. # CLINICAL PERSPECTIVE {#article-title-34}

Preferential splenic CD8+ T-cell activation in rituximab-nonresponder patients with immune thrombocytopenia

The pathogenic role of B cells in immune thrombocytopenia (ITP) has justified the therapeutic use of anti-CD20 antibodies such as rituximab (RTX). However, 60% of ITP patients do not respond to RTX. To decipher the mechanisms implicated in the failure of RTX, and because the spleen plays a well-recognized role in ITP pathogenesis, 12 spleens from ITP patients who had been nonresponders to RTX therapy were compared with 11 spleens from RTX-untreated ITP patients and 9 controls. We here demonstrate that in RTX-nonresponder ITP patients, preferential Th1 and Tc1 T lymphocyte polarizations occur, associated with an increase in splenic effector memory CD8(+) T-cell frequency. Moreover, in the RTX- nonresponder patient group, the CD8(+) T-cell repertoire displays a restricted pattern. In the blood, the phenotype of CD8(+) T cells before and after RTX treatment is not modified in responders or nonresponders. Altogether, these results demonstrate for the first time an activation of splenic CD8(+) T cells in ITP patients who did not respond to RTX and suggest their involvement in platelet destruction in these patients.

Efficacy of Azacitidine in autoimmune and inflammatory disorders associated with myelodysplastic syndromes and chronic myelomonocytic leukemia

This retrospective study describes efficacy of Azacitidine on autoimmune disorders (AID) associated with MDS/CMML in 22 patients. Response of AID to Azacitidine was observed in 19 patients (86%). Reduction or discontinuation of steroids and/or immunosuppressive therapy (IST) was possible in 16 cases (73%). Hematologic response was seen in 55% of the patients. MDS/CMML and AID evolution was concordant in 13 cases (59%): both favorable (n=11), both unfavorable (n=2), but AID improved while MDS/CMML worsened (n=8) and vice versa (n=1). Azacitidine frequently seems effective in controlling steroid-dependent AID associated with MDS/CMML, but prospective studies are necessary to confirm those findings.

Pituitary Involvement in Granulomatosis With Polyangiitis: Report of 9 Patients and Review of the Literature

AbstractPituitary dysfunction is a rare manifestation of granulomatosis with polyangiitis (GPA) (Wegener). The main aim of this multicenter retrospective study was to describe the characteristics and outcomes of pituitary manifestations in patients with GPA included in the French Vasculitis Study Group database.Among the 819 GPA patients included in the database, 9 (1.1%) had pituitary involvement. The median age at diagnosis of GPA and pituitary involvement was 46 and 50.8 years, respectively. Pituitary involvement was present at onset of GPA in 1 case and occurred later in 8 patients after a median follow up of 58.5 months. When pituitary dysfunction occurred, 8 patients had active disease at other sites including ENT (n = 6), eye (n = 4), or central nervous system (n = 3) involvement. The most common hormonal dysfunctions were diabetes insipidus (n = 7) and hypogonadism (n = 7). Magnetic resonance imaging was abnormal in 7 patients. The most common lesions were an enlargement of the pituitary gland, thickening of the pituitary stalk, and loss of posterior hypersignal on T1-weighed images. All patients were treated with corticosteroid therapy and 8 patients received immunosuppressive agents for the pituitary involvement, including cyclophosphamide (n = 3), rituximab (n = 2), and methotrexate (n = 3). After a median follow-up of 9.2 years, GPA was in complete remission in 7 patients, but 8 patients were still under hormone replacement therapy. Among the 5 patients who had a subsequent MRI, 2 had complete resolution of pituitary lesions.By combining our study and the literature review, the frequency of hypogonadism and diabetes insipidus, among the patients with pituitary dysfunction, can be estimated at 78% and 71% respectively. Despite a high rate of systemic disease remission on maintenance therapy, 86% of the patients had persistent pituitary dysfunction. The patients who recovered from pituitary dysfunction had all been treated by cyclophosphamide.Pituitary disease in GPA occurs mostly several months or years after diagnosis. There is no correlation between hormonal, radiologic, and systemic outcome. Although immunosuppressive drugs improve the systemic disease, hormonal deficiencies usually persist. It is therefore important to shorten diagnostic delays and treat these patients early in the course of disease before irreversible damage occur.

Ustekinumab inhibits Th1 and Th17 polarisation in a patient with giant cell arteritis

Although glucocorticoids (GC) remain the corner stone of giant cell arteritis (GCA) treatment, GC-sparing strategies are needed because GC are responsible for side effects.1 Recent advances in the pathophysiology of GCA showed that CD4+ T cells are recruited in the arterial wall and polarised into Th1 and Th17 cells,2 3 the latter being sensitive to GC-mediated suppression, whereas Th1 response persists in GC-treated patients,2 which triggers the recruitment of macrophages4 and could be implicated in the occurrence of relapses when GC are tapered. Interleukin (IL)-12 and IL-23 are two cytokines involved in Th1 and Th17 polarisations, respectively.5 These two cytokines share a common subunit (p40), which allows ustekinumab, a humanised anti-p40 monoclonal antibody, to target both IL-12 and IL-23 pathways, thus disrupting in theory Th1 and Th17 immune responses.6 Recently, an open-label study reported on the efficacy and safety of …

Should mild hypogammaglobulinemia be managed as severe hypogammaglobulinemia? A study of 389 patients with secondary hypogammaglobulinemia

BACKGROUND Although secondary hypogammaglobulinemia is more frequent than primary hypogammaglobulinemia, its etiology and management are poorly described, particularly for mild hypogammaglobulinemia. METHODS This retrospective observational study included all adult patients with a gammaglobulin level <6.4g/L on serum electrophoresis identified at Dijon teaching hospital between April and September 2012. Clinico-biological features, etiologies and infectious complications were collected at inclusion and compared between group 1 (gammaglobulin <5g/L, severe hypogammaglobulinemia), and group 2 (gammaglobulin <6.4 and ≥5g/L, mild hypogammaglobulinemia). RESULTS Among the 4011 serum electrophoreses, 570 samples from 389 patients had gammaglobulin levels below 6.4g/L: 156 (40%) in group 1 and 233 (60%) in group 2. Mean age±SD was 67 (15) years, and sex ratio was 1.04 (M/F) with no difference between the two groups. An etiology was identified in 79% and 58% of patients in groups 1 and 2, respectively (p<0.0001). The main etiologies were similar in both groups and included malignant hemopathy treated with cytostatic agents (n=129, 33%), smoldering or newly-diagnosed hemopathy without treatment (n=49, 13%) and immunosuppressive treatment (n=91, 23%). The incidence of hypogammaglobulinemia-related infections was 22/100/year, with no significant difference between the two groups (p=0.17). Vaccination coverage against pneumococcus was 33%, and higher in group 1 (46% vs. 24%; p<0.0001). When no cause was known at inclusion, an etiology was discovered in 22/130 patients (17%), 11 in each group. CONCLUSIONS Though mild hypogammaglobulinemia does not meet the classical criteria for hypogammaglobulinemia (<5g/L), the etiology and infectious risk are similar. It therefore requires investigation and vaccination.

B cell depleting therapy regulates splenic and circulating T follicular helper cells in immune thrombocytopenia

B cells are involved in immune thrombocytopenia (ITP) pathophysiology by producing antiplatelet auto-antibodies. However more than a half of ITP patients do not respond to B cell depletion induced by rituximab (RTX). The persistence of splenic T follicular helper cells (TFH) that we demonstrated to be expanded during ITP and to support B cell differentiation and antiplatelet antibody-production may participate to RTX inefficiency. Whereas it is well established that the survival of TFH depends on B cells in animal models, nothing is known in humans yet. To determine the effect of B cell depletion on human TFH, we quantified B cells and TFH in the spleen and in the blood from ITP patients treated or not with RTX. We showed that B cell depletion led to a dramatic decrease in splenic TFH and in CXCL13 and IL-21, two cytokines predominantly produced by TFH. The absolute count of circulating TFH and serum CXCL13 also decreased after RTX treatment, whatever the therapeutic response. Therefore, we showed that the maintenance of TFH required B cells and that TFH are not involved in the inefficiency of RTX in ITP.