Combination of monoclonal antibodies targeting type 2 inflammation for severe asthma and eosinophilic granulomatosis with polyangiitis.

Monoclonal antibodies targeting type 2 inflammation are promising treatments for eosinophilic-associated diseases. There is growing interest in the potential benefits of combining two biologics to treat patients with poorly controlled conditions. We present a case of a 54-year-old female patient affected with a relapsing-refractory ANCA myeloperoxidase positive eosinophilic granulomatosis with polyangiitis (EGPA), presenting with difficult-to-treat asthma and rhino-sinusitis manifestations. She failed several biologics, including omalizumab 300 mg, mepolizumab 100 mg, and benralizumab 30 mg every 8 weeks. A switch to dupilumab led to significant eosinophilia (7.69 × 109/L) as well as systemic symptoms, and a deterioration of asthma control. Therefore, a combination of dupilumab-benralizumab was started, leading to better nasal and ear outcomes, asthma control and decrease in blood eosinophils. During the 12-month treatment, no adverse effects were observed. We conducted an extensive literature search in MEDLINE for original articles published until August 1st, 2023 reporting the combination of anti-type 2 biologics. A total of 51 cases were retrieved from the literature. Omalizumab was the most frequently combined drugs (34 cases). Combination therapy led to reduction of asthma exacerbations and glucocorticoid intake, though was ineffective only for one EGPA patient. Only one patient on omalizumab-mepolizumab therapy reported a mild adverse reaction. Combination biologic therapies for conditions which share pathogenic pathways appears to be both safe and effective. This approach may benefit patients with uncontrolled conditions and counter side effects of biologics, like dupilumab-related hypereosinophilia.

Expression and role of CCR6/CCL20 chemokine axis in pulmonary sarcoidosis.

We have shown previously that the chemokine receptors CXCR3 and CXCR6 are coexpressed by Th1 cells infiltrating the lung and the granuloma of patients with sarcoidosis. In this study, we evaluated the role of CCL20/CCR6 interaction in the pathogenesis of acute and chronic pulmonary sarcoidosis. By flow cytometry and molecular analyses, we have demonstrated that Th1 cells isolated from the bronchoalveolar lavage (BAL) of patients with sarcoidosis and T cell alveolitis are equipped with CCR6. Furthermore, CCR6(+) T cells coexpressed the chemokine receptors CXCR3 and CXCR6. Immunohistochemical analysis of lung specimens has shown that CCR6(+) T cells infiltrate lung interstitium and surround the central core of the granuloma. It is interesting that CCR6 was never detected on the alveolar macrophage (AM) surface, and it is observed in the cytoplasm of AMs from patients with sarcoidosis and alveolitis. The CCR6 ligand CCL20 was expressed by macrophages, multinucleated giant cells, and epithelioid cells infiltrating the granuloma. Furthermore, detectable levels of CCL20 protein are seen in the BAL fluid components of patients with active sarcoidosis, and sarcoid AMs release the CCR6 ligand in vitro. From a functional point of view, sarcoid Th1 cells were able to respond to CXCL10, CXCL16, and CCL20 in migratory assays. In vitro kinetic studies demonstrated that CCR6 is induced rapidly by IL-2, IL-18, and IFN-gamma. In conclusion, T cells expressing CCR6, CXCR3, and CXCR6 act coordinately with respective ligands and Th1 inflammatory cytokines in the alveolitic/granuloma phases of the disease.

Cytokines, chemokines and other biomolecular markers in sarcoidosis.

In recent years our knowledge in terms of the network of interactions between immunocompetent cells that set the stage for the pathogenesis of sarcoidosis has continuously improved. Remarkable advances have been made in understanding general immunological and molecular aspects of the mechanisms leading to granuloma formation. In this manuscript we will review the current concepts on cellular interactions which define regulatory networks ultimately contributing to the granuloma formation at sites of disease activity in sarcoidosis. The biological effects of Th1 and Th2 cytokines in sarcoid lung will be taken into account and the importance of the local production of those chemokines and cytokines whose release has been recently demonstrated within the lung of patients with sarcoidosis will be emphasized.

T cells in the lung of patients with hypersensitivity pneumonitis accumulate in a clonal manner.

Hypersensitivity pneumonitis (HP) is characterized by an alveolitis sustained by CD8(+) T lymphocytes showing a limited expression of the T cell receptor (TCR). We previously demonstrated that a bias in T cell selection occurs in the lower respiratory tract of patients with HP, with a compartmentalization in the lung of CD8(+) T cells bearing (TCR)-beta variable (TCRBV) #2, 3, 5, 6, 8, and 13 gene segments. We herein characterized the clonal T cell populations present in the lung and in the blood of patients with HP. Heteroduplex analyses, cloning, and sequencing T cells bearing TCR indicate oligoclonal expansions of T cells expressing homologous or identical complementary-determining region 3. Furthermore, T cell clones isolated from the two compartments expressed similar, sometimes identical, junctional regions. Removal from antigenic exposure led to the disappearance of T cell clones. Our findings indicate that expansions of T lymphocytes bearing clonal TCRBV region gene segments take place in the lung of patients with HP during exposure. The evidence that identical T cell clones are present in the lung and the blood of the same patient suggests that the immune reaction occurring at lung level gives rise to a systemic reaction.

Multiple myeloma plasma cells show different chemokine receptor profiles at sites of disease activity.

Chemokines and their receptors play a pivotal role in the regulation of B-lymphocyte trafficking. This study was aimed at investigating the pattern of chemokine receptor expression, including CCR1 to CCR3, CCR5 to CCR7, CXCR1 to CXCR5, and the migration ability of multiple myeloma (MM) plasma cells (PC). PC were recovered from the bone marrow (BM) of 29 MM patients, extramedullary sites of 10 patients and the BM of five controls. Flow cytometry analysis showed that the receptors mainly expressed on malignant BM PC were represented by CXCR4 (70% of patients), CCR1 (25%), CCR2 (25%), CCR5 (17%) and CXCR3 (20%), while other receptors were commonly lacking. The analysis performed on extramedullary (peripheral blood and pleural effusion) malignant PC demonstrated that the most represented receptors were CXCR4 (100%), CCR2 (66%) and CXCR1 (60%). The migratory capability of malignant PC at resting conditions identified three groups of patients with different migration (low, intermediate and high). As CXCR4 was the relevant chemokine receptor expressed by MM PC, its ligand CXCL12 induced their migration. These data suggest that malignant PC from MM display different chemokine receptor profiles and that CXCR4 is fully functional and might play a role in the spreading of the disease.

Role for CXCR6 and its ligand CXCL16 in the pathogenesis of T-cell alveolitis in sarcoidosis.

RATIONALE: Receptor expression dictates the spectrum of chemokine actions on immunocompetent cells. We have previously shown that the chemokine receptor CXCR3 is highly expressed by T-helper type 1 (Th1) cells infiltrating the lungs of patients with sarcoidosis. OBJECTIVES: The evaluation of the role of Bonzo/CXCR6 and its ligand CXCL16 in the pathogenesis of sarcoidosis. METHODS: Immunocompetent cells infiltrating sarcoid lung have been evaluated by flow cytometry, confocal microscopy, immunohistochemical and molecular analysis, and functional assays. MAIN RESULTS: Th1 cells isolated from the bronchoalveolar lavage of patients with sarcoidosis and T-cell alveolitis coexpressed CXCR3 and CXCR6. Immunohistochemical analysis of lung specimens has shown that CXCR6+ T cells infiltrated lung interstitium surrounding the central core of the granuloma. The CXCR6 ligand CXCL16 was abundantly expressed by macrophages infiltrating sarcoid tissue and/or forming the granuloma core. From a functional point of view, sarcoid Th1 cells were able to respond to CXCL10 and CXCL16 in migratory assay. In vitro kinetic studies demonstrated that, although CXCR3 was rapidly induced by interleukin (IL)-15 and IL-18, CXCR6 induction was slow (8 d) and mainly regulated by IL-15. CONCLUSIONS: T cells coexpressing CXCR3 and CXCR6 act coordinately with respective ligands and Th1 inflammatory cytokines in the alveolitic/granuloma phases of the disease.

Applied clinical immunology in sarcoidosis.

Staging of sarcoidosis needs a synthesis of clinical features, histology, radiology, biochemical changes, and immunologic aberrations to distinguish this disease from nonspecific sarcoid-tissue reactions. The main aim of this report is to offer readers an overview on immunologic markers that have been evaluated in the last years with the ultimate goal of relating their determination to the management of the disease. The first part is devoted to immunologic markers that have been proposed to define the activity of the T-cell component of the sarcoid inflammatory process. In the second part of the paper, we will provide a descriptive definition of immunologic markers of activity of sarcoid macrophages relating them to the clinical course of sarcoidosis.