Takehiro Tanaka

Ocular adnexal IgG4-related disease has uniform clinicopathology

IgG4‐related disease is a recently proposed clinical entity with several unique clinicopathological features. Ocular adnexal IgG4‐related disease, however, has not well been clarified. The purpose of the present study was to examine 21 patients (10 men, 11 women; age range, 39–86 years) with ocular adnexal IgG4‐related disease. In 17 out of 21 patients (81%), the lacrimal glands were involved and bilateral lacrimal gland swelling was frequently observed (n = 12; 70.6%). In contrast, the conjunctiva was not involved in any of the patient. Histology was uniform with marked lymphoplasmacytic infiltration admixed with dense fibrosis, similar to previous reports of IgG4‐related disease. Immunostaining detected numerous aggregates of IgG4‐positive plasma cells. Serum IgG4 was higher than normal in 10 of the 13 patients tested, although it was measured after treatment in almost all cases. Interestingly, immunoglobulin heavy chain gene rearrangement was detected in two of 17 patients (12%) examined. The present results show that ocular adnexal IgG4‐related disease has uniform clinicopathology: that is, disease involving the bilateral lacrimal glands with lymphoid hyperplasia and fibrosis, but not the conjunctiva. And presence of immunoglobulin heavy chain gene rearrangement suggests the possibility of B‐cell lymphoma arising in a background of IgG4‐related chronic inflammation.

Systemic IgG4-related lymphadenopathy: a clinical and pathologic comparison to multicentric Castleman's disease

IgG4-related disease sometimes involves regional and/or systemic lymph nodes, and often clinically and/or histologically mimics multicentric Castlemans disease or malignant lymphoma. In this study, we examined clinical and pathologic findings of nine patients with systemic IgG4-related lymphadenopathy. None of these cases were associated with human herpes virus-8 or human immunodeficiency virus infection, and there was no T-cell receptor or immunoglobulin gene rearrangement. Histologically, systemic IgG4-related lymphadenopathy was classified into two types by the infiltration pattern of IgG4-positive cells: interfollicular plasmacytosis type and intra-germinal center plasmacytosis type. The interfollicular plasmacytosis type showed either Castlemans disease-like features or atypical lymphoplasmacytic and immunoblastic proliferation-like features. By contrast, the intra-germinal center plasmacytosis type showed marked follicular hyperplasia, and infiltration of IgG4-positive cells mainly into the germinal centers, and some cases exhibited features of progressively transformed germinal centers. Interestingly, eight of our nine (89%) cases showed eosinophil infiltration in the affected lymph nodes, and examined patients showed high elevation of serum IgE. Laboratory examinations revealed elevation of serum IgG4 and soluble interleukin-2 receptors. However, the levels of interleukin-6, C-reactive protein, and lactate dehydrogenase were within normal limits or only slightly elevated in almost all patients. One patient showed a high interleukin-6 level whereas C-reactive protein was within the normal limit. Autoantibodies were examined in five patients and detected in four. Compared with the previously reported cases of multicentric Castlemans disease, our patients with systemic IgG4-related lymphadenopathy were significantly older and had significantly lower C-reactive protein and interleukin-6 levels. In conclusion, in our systemic IgG4-related lymphadenopathy showed pathologic features only partially overlapping those of multicentric Castlemans disease, and serum data (especially C-reactive protein and interleukin-6) are useful for differentiating the two. Our findings of eosinophil infiltration in the affected tissue and elevation of serum IgE may suggest an allergic mechanism in the pathogenesis of systemic IgG4-related lymphadenopathy.

Multicentric Castleman's disease with abundant IgG4-positive cells: a clinical and pathological analysis of six cases

Background Differentiation between multicentric Castlemans disease and systemic immunoglobulin (Ig) G4-related lymphadenopathy is sometimes difficult. It has been suggested that measurement of the IgG4-/IgG-positive cell ratio is useful for the differential diagnosis of the two diseases. However, the authors present a detailed report of six patients with multicentric Castlemans disease with abundant IgG4-positive cells (IgG4-/IgG-positive cell ratio, >40%). Results In the present series, the patients showed systemic lymphadenopathy, polyclonal hypergammaglobulinaemia and elevated serum interleukin-6 (IL-6) and C-reactive protein levels. Further, anaemia, hypoalbuminaemia, hypocholesterolaemia and thrombocytosis were observed. These findings were consistent with those of multicentric Castlemans disease. Although five patients showed elevated serum IgG4 levels, only two patients showed an increased serum IgG4/IgG ratio. However, the two patients showed highly elevated serum IgG4 levels, but the serum IgG4/IgG ratios were, although increased, not very high. Also, a patient with increased serum IgG4/IgG ratio showed a good response to antihuman IL-6 receptor monoclonal antibody (tocilizumab). Histologically, the germinal centres were mostly small and regressive, and frequently penetrated by hyalinised blood vessels, and there was no eosinophil infiltration. These findings were different from those of IgG4-related lymphadenopathy. Conclusions The authors conclude that multicentric Castlemans disease sometimes occurs with abundant IgG4-positive cells and elevated serum IgG4 levels. Therefore, the two diseases cannot be differentially diagnosed by immunohistochemical staining alone. Laboratory findings, especially IL-6 level, C-reactive protein level and platelet count, are important for the differential diagnosis of the two diseases.

Synthetic retinoid Am80 ameliorates chronic graft-versus-host disease by down-regulating Th1 and Th17

Chronic GVHD (cGVHD) is a main cause of late death and morbidity after allogeneic hematopoietic cell transplantation, but its pathogenesis remains unclear. We investigated the roles of Th subsets in cGVHD with the use of a well-defined mouse model of cGVHD. In this model, development of cGVHD was associated with up-regulated Th1, Th2, and Th17 responses. Th1 and Th2 responses were up-regulated early after BM transplantation, followed by a subsequent up-regulation of Th17 cells. Significantly greater numbers of Th17 cells were infiltrated in the lung and liver from allogeneic recipients than those from syngeneic recipients. We then evaluated the roles of Th1 and Th17 in cGVHD with the use of IFN-γ-deficient and IL-17-deficient mice as donors. Infusion of IFN-γ(-/-) or IL-17(-/-) T cells attenuated cGVHD in the skin and salivary glands. Am80, a potent synthetic retinoid, regulated both Th1 and Th17 responses as well as TGF-β expression in the skin, resulting in an attenuation of cutaneous cGVHD. These results suggest that Th1 and Th17 contribute to the development of cGVHD and that targeting Th1 and Th17 may therefore represent a promising therapeutic strategy for preventing and treating cGVHD.

IgG4-producing marginal zone B-cell lymphoma.

IgG4-related disease is a recently proposed clinical entity with several unique clinicopathological features. A chronic inflammatory state with marked fibrosis, which can often be mistaken for malignancy, especially by clinical imaging analyses, unifies these features. Little is known about lymphomagenesis in the context of IgG4-related disease, we recently first reported the ocular adnexal marginal zone B-cell lymphomas arising from IgG4-related disease. To the best of our knowledge, no existing study has ever established the neoplastic potential of IgG4-producing cells. In the present report, we describe the first IgG4-producing lymphoma. The patient was a 72-year-old male who was being followed for an asbestos-related pleural plaque. During follow-up, computed tomography revealed bilateral renal masses and multiple swollen retroperitoneal lymph nodes. A retroperitoneal lymph node biopsy was performed. Histologically, the interfollicular areas were expanded by medium to large plasmacytoid cells. These plasmacytoid cells showed nuclear pleomorphism and had prominent Russell bodies. Immunohistochemistry and double immunofluorescence staining of these cells revealed IgG4 positivity and monotypic lambda-light chain predominance. A portion of these cells were partially positive for CD20, negative for CD3, and somewhat faintly positive for CD138. In addition, serum IgG4 was elevated. Southern blot analysis of the lymph node specimen detected immunoglobulin heavy chain gene rearrangement. The present study indicates that, not only can malignant lymphomas occur in the setting of IgG4-related disease, but IgG4-producing cells can also be neoplastic.

Duodenal and nodal follicular lymphomas are distinct: the former lacks activation-induced cytidine deaminase and follicular dendritic cells despite ongoing somatic hypermutations

Although most follicular lymphomas are believed to be of nodal origin, they sometimes originate from the duodenum. We have reported that the latter differ from nodal follicular lymphomas in having lower clinical stages and uniformly low histological grades, along with variable region of immunoglobulin heavy chain gene (VH) usage that is more similar to mucosa-associated lymphoid tissue (MALT) lymphomas. Little is known, however, about whether they possess other characteristics of nodal follicular lymphomas, particularly ongoing mutations with follicular dendritic cells. We examined 17 cases for which PCR identified the monoclonal bands of the immunoglobulin gene. The duodenal cases showed ongoing mutations, but they lacked activation-induced cytidine deaminase (AID) expression, a statistically significant difference from the nodal cases (P<0.001), and their follicular dendritic cell networks were disrupted. Moreover, not only were VH deviations observed but also they used very restricted VH genes. Although the mechanisms of ongoing mutation without AID and follicular dendritic cell were not clarified, restricted VH usage strongly suggested that antigen stimulation was involved, and that was similar to MALT lymphomas. In conclusion, duodenal follicular lymphomas were shown to be unique, in that they had ongoing hypermutations such as nodal cases, but the mechanisms involved in the hypermutation were quite different; furthermore, restricted VH usage suggested a strong similarity to the antigen-dependent origin of MALT lymphomas.

Expression of Phosphorylated Ser70 of Bcl-2 Correlates with Malignancy in Human Colorectal Neoplasms

Purpose: Bcl-2 is a model apoptosis suppressor postulated to promote tumorigenesis. Recently, it has been reported that Bcl-2 undergoes phosphoregulation of its Ser70 to substantially alter its molecular function. Previous studies further suggest that such phospho-Bcl-2 regulation may influence tumor progression in colorectal and other cancers; however, phosphorylation status of the Ser70 of Bcl-2 (pSer70) in vivo in tumors remains obscure. To elucidate this question that may suggest the biological role, we molecularly screened a panel of human colorectal adenomas and adenocarcinomas for endogenous expression of pSer70 Bcl-2. Experimental Design: An antibody specific against pSer70 Bcl-2 was generated for thorough immunohistochemical examination of paraffin-embedded tumor specimens, allowing detection of the endogenously expressed antigen among a range of Bcl-2-positive colorectal neoplasms, including 75 tubular adenomas, 114 adenocarcinomas, and 15 cases of cancer in adenomas. Results: Loss of pSer70 Bcl-2 expression was observed in adenocarcinomas in a differentiation-dependent manner (positivities: well differentiated 63%, moderately differentiated 52%, and poorly differentiated 12%), whereas tubular adenomas maintained their expression (positivity 88%). Interestingly, an inverse correlation was found between expression of pSer70 Bcl-2 and Ki-67 antigen in those cases of cancer in adenoma (P < 0.01). It was further observed that loss of pSer70 Bcl-2 expression was associated with significantly shorter survival (P < 0.05) and correlated with clinical stages and lymph node metastasis (P < 0.05 and P < 0.05, respectively). Conclusions: Loss of pSer70 Bcl-2 expression is closely linked to biological aggressiveness in colorectal tumors and represents a statistically significant molecular index for prognosis of patients with these tumors.

Evaluation of Mucosal Healing in Ulcerative Colitis by Fecal Calprotectin Vs. Fecal Immunochemical Test.

OBJECTIVES:We previously showed that a quantitative fecal immunochemical test (FIT) can predict mucosal healing (MH) in ulcerative colitis (UC). Fecal calprotectin (Fcal) has also been reported as an important biomarker of UC activity. The aim of this study was to compare the predictive ability of these two fecal markers for MH in UC.METHODS:FIT and Fcal were examined in stool samples from consecutive UC patients who underwent colonoscopy. Mucosal status was assessed via the Mayo endoscopic subscore (MES).RESULTS:In total, 105 colonoscopies in 92 UC patients were evaluated in conjunction with the FIT and Fcal results. Both FIT and Fcal results were significantly correlated with MES (Spearman’s rank correlation coefficient: 0.61 and 0.58, respectively). The sensitivity and specificity of the FIT values (<100 ng/ml) for predicting MH (MES 0 alone) were 0.95 and 0.62, respectively, whereas those of Fcal (<250 μg/g) were 0.82 and 0.62, respectively. The sensitivities became similar when MH was defined as MES 0 or 1 (0.86 vs. 0.86). Although the predictability of MH evaluated by the area under the receiver operating characteristics curve was similar for the two fecal markers (FIT 0.83 vs. Fcal 0.82 for MES 0 alone), the FIT results were relatively robust regardless of the cutoff value selected.CONCLUSIONS:Both FIT and Fcal can efficiently predict MH in UC, but FIT appears to be more sensitive than Fcal for predicting MES 0 alone.

Programmed Death-1 Pathway in Host Tissues Ameliorates Th17/Th1-Mediated Experimental Chronic Graft-versus-Host Disease

Chronic graft-versus-host disease (GVHD) is a major cause of late death and morbidity after allogeneic hematopoietic cell transplantation, but its pathogenesis remains unclear. We investigated the role of the programmed death-1 (PD-1) pathway in chronic GVHD using a well-defined mouse model of B10.D2 (H-2d) donor to BALB/c (H-2d) recipients. PD-1 expression on allogeneic donor T cells was upregulated continuously in chronic GVHD development, whereas PD-L1 expression in host tissues was transiently upregulated and declined to basal levels in the late posttransplant period. Blockade of the PD-1 pathway by anti–PD-1, anti–PD-L1, or anti–PD-L2 mAbs exacerbated clinical and pathologic chronic GVHD. Chimeric mice revealed that PD-L1 expression in host tissues suppressed expansion of IL-17+IFN-γ+ T cells, and that PD-L1 expression on hematopoietic cells plays a role in the development of regulatory T cells only during the early transplantation period but does not affect the severity of chronic GVHD. Administration of the synthetic retinoid Am80 overcame the IL-17+IFN-γ+ T cell expansion caused by PD-L1 deficiency, resulting in reduced chronic GVHD damage in PD-L1−/− recipients. Stimulation of the PD-1 pathway also alleviated chronic GVHD. These results suggest that the PD-1 pathway contributes to the suppression of Th17/Th1-mediated chronic GVHD and may represent a new target for the prevention or treatment of chronic GVHD.

Droplet digital PCR measurement of HER2 in patients with gastric cancer

Background:Although there are some new criteria for human epidermal growth factor receptor 2 (HER2) expression with immunohistochemistry/fluorescence in situ hybridisation (IHC/FISH) in gastric cancer, the method is still ambiguous and is somewhat dependent on the subjective qualities of the evaluator.Methods:We used droplet digital polymerase chain reaction (ddPCR) to evaluate HER2 amplification in formalin-fixed and paraffin-embedded (FFPE) samples and cell-free serum circulating tumour DNA (ctDNA) in 25 patients with gastric cancer.Results:The concordance rate of HER2 amplification examined in FFPE samples with ddPCR and IHC/FISH was 92% (23 out of 25). The concordance rate of FFPE with ctDNA was not high (62.5%); however, patients who were HER2-positive by ctDNA had significantly shorter survival compared with HER2-negative patients.Conclusions:Our results demonstrated that this ddPCR method was as effective as IHC/FISH and therefore might become a standard method for analysing not only FFPE but also ctDNA.