Yuka Gion

Clinicopathologic analysis of TAFRO syndrome demonstrates a distinct subtype of HHV‐8‐negative multicentric Castleman disease

Multicentric Castleman disease (MCD) describes a heterogeneous group of disorders involving systemic inflammation, characteristic lymph node histopathology, and multi‐organ dysfunction because of pathologic hypercytokinemia. Whereas Human Herpes Virus‐8 (HHV‐8) drives the hypercytokinemia in a cohort of immunocompromised patients, the etiology of HHV‐8‐negative MCD is idiopathic (iMCD). Recently, a limited series of iMCD cases in Japan sharing a constellation of clinical features, including thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O) has been described as TAFRO syndrome. Herein, we report clinicopathological findings on 25 patients (14 males and 11 females; 23 Japanese‐born and two US‐born), the largest TAFRO syndrome case series, including the first report of cases from the USA. The median age of onset was 50 years old (range: 23–72). The frequency of each feature was as follows: thrombocytopenia (21/25), anasarca (24/25), fever (21/25), organomegaly (25/25), and reticulin fibrosis (13/16). These patients frequently demonstrated abdominal pain, elevated serum alkaline phosphatase levels, and acute kidney failure. Surprisingly, none of the cases demonstrated marked hypergammoglobulinemia, which is frequently reported in iMCD. Lymph node biopsies revealed atrophic germinal centers with enlarged nuclei of endothelial cells and proliferation of endothelial venules in interfollicular zone. 23 of 25 cases were treated initially with corticosteroids; 12 patients responded poorly and required further therapy. Three patients died during the observation period (median: 9 months) because of disease progression or infections. TAFRO syndrome is a unique subtype of iMCD that demonstrates characteristic clinicopathological findings. Further study to clarify prognosis, pathophysiology, and appropriate treatment is needed. Am. J. Hematol. 91:220–226, 2016.

T helper 2 and regulatory T-cell cytokine production by mast cells: a key factor in the pathogenesis of IgG4-related disease

IgG4-related disease is a systemic disorder with unique clinicopathological features and uncertain etiological features and is frequently related to allergic disease. T helper 2 and regulatory T-cell cytokines have been reported to be upregulated in the affected tissues; thus, the production of these cytokines by T helper 2 and regulatory T cells has been suggested as an important factor in the pathogenesis of IgG4-related disease. However, it is not yet clear which cells produce these cytokines in IgG4-related disease, and some aspects of the disorder cannot be completely explained by T-cell-related processes. To address this, we analyzed paraffin-embedded sections of tissues from nine cases of IgG4-related submandibular gland disease, five cases of submandibular sialolithiasis, and six cases of normal submandibular gland in order to identify potential key players in the pathogenesis of IgG4-related disease. Real-time polymerase chain reaction analysis confirmed the significant upregulation of interleukin (IL)4, IL10, and transforming growth factor beta 1 (TGFβ1) in IgG4-related disease. Interestingly, immunohistochemical studies indicated the presence of mast cells expressing these cytokines in diseased tissues. In addition, dual immunofluorescence assays identified cells that were double-positive for each cytokine and for KIT, which is expressed by mast cells. In contrast, the distribution of T cells did not correlate with cytokine distribution in affected tissues. We also found that the mast cells were strongly positive for IgE. This observation supports the hypothesis that mast cells are involved in IgG4-related disease, as mast cells are known to be closely related to allergic reactions and are activated in the presence of elevated non-specific IgE levels. In conclusion, our results indicate that mast cells produce T helper 2 and regulatory T-cell cytokines in tissues affected by IgG4-related disease and possibly have an important role in disease pathogenesis.

Interleukin 13-positive mast cells are increased in immunoglobulin G4-related sialadenitis

Interleukin (IL)-13 is a T helper 2 (Th2) cytokine that plays important roles in the pathogenesis of asthma. IL-13 induces hypersensitivity of the airways, increased mucous production, elevated serum immunoglobulin (Ig) E levels, and increased numbers of eosinophils. Many patients with IgG4-related disease have allergic backgrounds and show elevated serum IgE levels and an increase in the number of eosinophils. Upregulation of Th2/regulatory T (Treg) cytokines, including IL-13, has been detected in affected tissues of patients with IgG4-related disease. We previously reported that mast cells might be responsible for the production of the Th2/Treg cytokines IL-4, IL-10, and transforming growth factor (TGF)-β1 in IgG4-related disease. In this study, immunohistochemical analysis showed increased numbers of IL-13-positive mast cells in IgG4-related disease, which suggests that mast cells also produce IL-13 and contribute to elevation of serum IgE levels and eosinophil infiltration in IgG4-related disease.

Elevated serum interferon γ-induced protein 10 kDa is associated with TAFRO syndrome

Multicentric Castleman disease (MCD) is a heterogeneous lymphoproliferative disorder. It is characterized by inflammatory symptoms, and interleukin (IL)-6 contributes to the disease pathogenesis. Human herpesvirus 8 (HHV-8) often drives hypercytokinemia in MCD, although the etiology of HHV-8-negative MCD is idiopathic (iMCD). A distinct subtype of iMCD that shares a constellation of clinical features including thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O) has been reported as TAFRO-iMCD, however the differences in cytokine profiles between TAFRO-iMCD and iMCD have not been established. We retrospectively compared levels of serum interferon γ-induced protein 10 kDa (IP-10), platelet-derived growth factor (PDGF)-AA, interleukin (IL)-10, and other cytokines between 11 cases of TAFRO-iMCD, 6 cases of plasma cell type iMCD, and 21 healthy controls. During flare-ups, patients with TAFRO-iMCD had significantly higher serum IP-10 and tended to have lower PDGF-AA levels than the other 2 groups. In addition, serum IL-10, IL-23, and vascular endothelial growth factor-A were elevated in both TAFRO-iMCD and iMCD. Elevated serum IP-10 is associated with inflammatory diseases including infectious diseases. There was a strong correlation between high serum IP-10 and the presence of TAFRO-iMCD, suggesting that IP-10 might be involved in the pathogenesis of TAFRO-iMCD.

A subset of ocular adnexal marginal zone lymphomas may arise in association with IgG4-related disease

We previously suggested a relationship between ocular immunoglobulin (Ig)G4-related disease (IgG4-RD) and marginal zone lymphomas (MZLs). However, the cytokine background associated with these disorders and whether it differs between ocular adnexal MZLs with (IgG4-associated MZL) and without (IgG4-negative MZL) numerous IgG4+ plasma cells are unknown. In this study, we identified the mRNA expression pattern of Th2 and regulatory T-cell (Treg) cytokines in IgG4-RD and in IgG4-associated MZL and IgG4-negative MZL using real-time polymerase chain reaction analysis. Ocular IgG4-RD and IgG4-associated MZL exhibited significantly higher expression ratios of interleukin (IL)-4/β-actin, IL-10/β-actin, IL-13/β-actin, transforming growth factor (TGF) β1/β-actin, and FOXP3/β-actin than did IgG4-negative MZL (p < 0.05). This finding further supports our prior observations that a significant subset of ocular MZLs arises in the setting of IgG4-RD. Furthermore, the presence of a different inflammatory background in IgG4-negative MZLs suggests that IgG4-associated MZLs may have a different pathogenesis.

Epstein-Barr virus-infected cells in IgG4-related lymphadenopathy with comparison with extranodal IgG4-related disease.

IgG4-related lymphadenopathy with increased numbers of Epstein-Barr virus (EBV)-infected cells has been reported but not fully described. We analyzed 31 cases of IgG4-related lymphadenopathy and 24 cases of extranodal IgG4-related diseases for their possible relationship with EBV. Other types of reactive lymph nodes (22) and angioimmunoblastic T-cell lymphoma (AITL) (10) were also studied for comparison. EBV-encoded RNA (EBER) in situ hybridization revealed EBER+ cells in 18 of 31 cases (58%) of IgG4-related lymphadenopathy. Increased EBER+ cells were found in only 4 of 22 (18.1%) non–IgG4-related reactive lymphoid hyperplasia in patients of a similar age (P=0.002) and in only 5 of 24 (21%) extranodal IgG4-related biopsies (P=0.006). Interestingly, all patients with EBER+ progressively transformed germinal center–type IgG4-related lymphadenopathy had systemic lymphadenopathy and/or extranodal involvement. AITL also is associated with EBV, and IgG4-related lymphadenopathy sometimes mimics the morphology of AITL; however, the number of IgG4+ cells in AITL was significantly less than that in IgG4-related lymphadenopathy (P<0.001). Increased numbers of regulatory T cells are seen in IgG4-related disease; however, there was not a significant difference between the EBER+ and EBER− cases. In conclusion, the presence of increased numbers of EBV-infected cells in IgG4-related lymphadenopathy, compared with other reactive lymphadenopathy or extranodal IgG4-related disease, suggests that there may be a relationship at least between nodal IgG4-related disease and EBV. It is important to avoid overdiagnosing these cases as malignant lymphomas or EBV-related lymphoproliferative disorders.

Regulatory T-cell infiltration in tongue squamous cell carcinoma

Abstract Conclusion: In tongue squamous cell carcinoma (SCC), high levels of regulatory T-cell (Treg) infiltration in tumor nests are observed in the cases with poor prognosis. Objectives: The role of Tregs in head and neck cancers remains unclear. The aim of this study was to observe the distribution of Tregs in different stages of tongue SCC and estimate the effects on prognosis. Methods: Thirty-four cases with tongue SCC were examined immunohistochemically for CD4, CD8, and Forkhead box P3 (Foxp3). Immunoreactive cells were counted in cancer stroma and nest regions, and relationships between cell numbers and disease-free survival rates were analyzed. Results: In the 34 cases, univariate analysis for disease-free survival indicated high-level infiltration of Tregs (CD4+Foxp3+) into both cancer nests and stroma and presence of helper T (CD4+Foxp3–) cells in cancer stroma as potential predictors of significantly worse prognosis. In early-stage cases (stage I/II), high-level infiltration of Tregs in cancer nests correlated significantly with poor disease-free survival rate. Multivariate analysis for disease-free survival found no independent variables.

Clinicopathological analysis of methotrexate-associated lymphoproliferative disorders: Comparison of diffuse large B-cell lymphoma and classical Hodgkin lymphoma types

Patients with rheumatoid arthritis often develop methotrexate‐associated lymphoproliferative disorders (MTX‐LPD) during MTX treatment. MTX‐LPD occasionally regresses spontaneously after simply discontinuing MTX treatment. In patients without spontaneous regression, additional chemotherapy is required to avoid disease progression. However, the differences between spontaneous and non‐spontaneous regression have yet to be elucidated. To clarify the factors important for spontaneous regression, we analyzed the clinicopathological features of 51 patients with rheumatoid arthritis who developed MTX‐LPD (diffuse large B‐cell lymphoma [DLBCL]‐type [n = 34] and classical Hodgkin lymphoma [CHL]‐type [n = 17]). We examined the interval from MTX discontinuation to the administration of additional chemotherapy. The majority of DLBCL‐type MTX‐LPD patients (81%) exhibited remission with MTX discontinuation alone. In contrast, the majority of CHL‐type MTX‐LPD patients (76%) required additional chemotherapy. This difference was statistically significant (P = 0.001). However, overall survival was not significantly different between DLBCL‐type and CHL‐type (91% vs 94%, respectively; P > 0.05). Thus, the morphological differences in the pathological findings of MTX‐LPD may be a factor for spontaneous or non‐spontaneous regression after discontinuation of MTX.

DNA Microarray Analysis of Submandibular Glands in IgG4-Related Disease Indicates a Role for MARCO and Other Innate Immune-Related Proteins.

AbstractIgG4-related disease (IgG4-RD) is a novel systemic disease entity characterized by elevated serum IgG4 and tissue infiltration of IgG4-positive plasma cells accompanied by severe fibrosis. Although recent studies demonstrated that innate immune cells including monocytes and macrophages might promote local fibrosis and IgG4 production, the pathological mechanism remains unclear. In this study, we sought to identify the disease-associated genes, especially innate immune molecules.Gene expression was analyzed by DNA microarray in submandibular glands (SMGs) from patients with IgG4-RD (n = 5), chronic sialoadenitis (CS) (n = 3), and controls (n = 3). Differentially expressed genes (DEGs) were validated by real-time polymerase chain reaction (PCR) and immunohistochemical staining in IgG4-RD (n = 18), CS (n = 4), Sjögren syndrome (n = 11), and controls (n = 10).Gene expression patterns in the 3 groups were quite different from each other by the pvclust method and principal components analysis. In IgG4-RD, 1028 upregulated genes and 692 downregulated genes were identified as DEGs (P < 0.05). Gene Ontology (GO) term analysis indicated that the upregulated DEGs in IgG4-RD encoded proteins involved in T/B cell activation and chemotaxis. PCR validated significantly higher expression of macrophage receptor with collagenous structure (MARCO), a pattern-recognition receptor, in IgG4-RD compared with the other groups (P < 0.01). Immunohistochemical analysis confirmed that the expression pattern of MARCO was similar to that of the M2 macrophage marker CD163.MARCO was identified as a disease-associated molecule in IgG4-RD by DNA microarray. Moreover, M2 macrophages might contribute to the initiation of IgG4-RD via MARCO.

Morphologic, flow cytometric, functional, and molecular analyses of S100B positive lymphocytes, unique cytotoxic lymphocytes containing S100B protein

Little is known about the S100B+ lymphocytes, which are unique human peripheral blood lymphocytes (PBL) containing the S100B protein. It has recently been shown that S100B is released from various types of S100B+ cells and exhibits varied cytokine‐like activities. In this study, we precisely characterized the S100B+ lymphocytes of healthy adults with respect to the proportion in the whole PBL, immunophenotypes, function, and their S100B mRNA expression and also evaluated their S100B‐releasing activity upon stimulation. S100B+ lymphocytes were detected in all individuals examined, and the proportion of S100B+ lymphocytes in the whole PBL ranged from 0.42% to 16.15% (mean, 4.21%). In addition, two subtypes of S100B+ lymphocytes, a CTL subtype (CD3+ CD8+ CD16‐) and a NK subtype (CD3‐ CD8‐ CD16+), were detected. The majority of the CTL subtype of S100B+ lymphocytes expressed the αβ‐T‐cell receptor. Surprisingly, S100B mRNA was detected not only in S100B+ lymphocytes, but also in every S100B‐ lymphocytes, although the expression levels of S100B mRNA in S100B‐ lymphocytes were much lower than those of S100B+ lymphocytes. The CTL subtype of S100B+ lymphocytes exhibited blastic morphological changes, proliferated and released S100B upon stimulation with phytohemagglutinin. The NK subtype of S100B+ lymphocytes exhibited morphological NK activity when cocultivated with NK‐sensitive target, K‐562 cells. Thus, the CTL subtype of S100B+ lymphocytes exhibit the biological characteristics of T cells, while the NK subtype of S100B+ lymphocytes exhibit the characteristics of NK cells. These results suggest that S100B+ lymphocytes are a particular subtype of cytotoxic lymphocytes that play a unique role in antitumor immunity.