Ibrutinib, obinutuzumab, and venetoclax in relapsed and untreated patients with mantle cell lymphoma: a phase 1/2 trial.

Ibrutinib, obinutuzumab, and venetoclax demonstrate synergy in preclinical models of mantle cell lymphoma (MCL). OAsIs (NCT02558816), a single-arm multicenter prospective phase 1/2 trial, aimed to determine the maximum tolerated dose of venetoclax in combination with fixed doses of ibrutinib and obinutuzumab, in relapsed MCL patients. At the venetoclax MTD, extension cohorts were opened for relapsed and untreated patients. Safety and efficacy were secondary objectives. Minimal residual disease (MRD) was assessed by allele-specific oligonucleotide quantitative polymerase chain reaction. Between 14 October 2015 and 29 May 2018, 48 patients were enrolled. No dose-limiting toxicity was reported, and venetoclax at 400 mg per day was chosen for extension. Eighteen (75%) relapsed and 8 (53%) untreated patients experienced grade 3/4 adverse events. The complete response rate assessed by positron emission tomography at the end of cycle 6 was 67% in relapsed and 86.6% in untreated patients. MRD clearance for evaluable patients was seen in 71.5% of relapsed (10/14 patients) and 100% of untreated MRD-evaluable patients (n = 12) at the end of 3 cycles. The median follow-up for relapsed patients was 17 months (range, 10-35 months). The 2-year progression-free survival (PFS) was 69.5% (95% confidence interval [CI], 52.9%-91.4%) and 68.6% (95% CI, 49.5%-95.1%) for overall survival. The median follow-up was 14 months (range, 5-19) for untreated patients, the 1-year PFS was 93.3% (95% CI, 81.5%-100%). The combination of obinutuzumab, ibrutinib, and venetoclax is well tolerated and provides high response rates, including at the molecular level, in relapsed and untreated MCL patients. This trial was registered at www.clinicaltrials.gov as #NCT02558816.

ALK-negative anaplastic large cell lymphoma with DUSP22 rearrangement has distinctive disease characteristics with better progression-free survival: a LYSA study.

ALK-negative anaplastic large cell lymphoma (ALCL) comprises subgroups harboring rearrangements of DUSP22 (DUSP22- R) or TP63 (TP63-R). Two studies reported 90% and 40% 5-year overall survival (OS) rates in 21 and 12 DUSP22-R/TP63- not rearranged (NR) patients, respectively, making the prognostic impact of DUSP22-R unclear. Here, 104 newly diagnosed ALK-negative ALCL patients (including 37 from first-line clinical trials) from the LYSA TENOMIC database were analyzed by break-apart fluorescence in situ hybridization assays for DUSP22-R and TP63-R. There were 47/104 (45%) DUSP22-R and 2/93 (2%) TP63-R cases, including one DUSP22-R/TP63-R case. DUSP22-R tumors more frequently showed CD3 expression (62% vs. 35%, P=0.01), and less commonly a cytotoxic phenotype (27% vs. 82%; P<0.001). At diagnosis, DUSP22- R ALCL patients more frequently had bone involvement (32% vs. 13%, P=0.03). The patient with DUSP22-R/TP63-R ALCL had a rapidly fatal outcome. After a median follow-up of 4.9 years, 5-year progression-free survival (PFS) and OS rates of 84 patients without TP63-R treated with curative-intent anthracycline-based chemotherapy were 41% and 53%, respectively. According to DUSP22 status, 5-year PFS was 57% for 39 DUSP22-R versus 26% for 45 triple-negative (DUSP22-NR/TP63-NR/ALK-negative) patients (P=0.001). The corresponding 5-year OS rates were 65% and 41%, respectively (P=0.07). In multivariate analysis, performance status and DUSP22 status significantly affected PFS, and distinguished four risk groups, with 4-year PFS and OS ranging from 17% to 73% and 21% to 77%, respectively. Performance status but not DUSP22 status influenced OS. The use of brentuximab vedotin in relapsed/refractory patients improved OS independently of DUSP22 status. Our findings support the biological and clinical distinctiveness of DUSP22- R ALK-negative ALCL. Its relevance to outcome in patients receiving frontline brentuximab vedotin remains to be determined.

Monomorphic epitheliotropic intestinal T-cell lymphoma comprises morphologic and genomic heterogeneity impacting outcome.

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare aggressive T-cell lymphoma most reported in Asia. We performed a comprehensive clinical, pathological and genomic study of 71 European MEITL patients (36 males, 35 females, median age 67 years). The majority presented with gastrointestinal involvement and had emergency surgery, and 40% had stage IV disease. The tumors were morphologically classified into two groups: typical (58%) and atypical (i.e., non-monomorphic or with necrosis, angiotropism or starry-sky pattern) (42%), sharing a homogeneous immunophenotypic profile (CD3+ [98%] CD4- [94%] CD5- [97%] CD7+ [97%] CD8+ [90%] CD56+ [86%] CD103+ [80%] cytotoxic marker+ [98%]) with more frequent expression of TCRgd (50%) than TCRab (32%). MYC expression (30% of cases) partly reflecting MYC gene locus alterations, correlated with non-monomorphic cytology. Almost all cases (97%) harbored deleterious mutation(s) and/or deletion of the SETD2 gene and 90% had defective H3K36 trimethylation. Other frequently mutated genes were STAT5B (57%), JAK3 (50%), TP53 (35%), JAK1 (12.5%), BCOR and ATM (11%). Both TP53 mutations and MYC expression correlated with atypical morphology. The median overall survival (OS) of 63 patients (43/63 only received chemotherapy after initial surgery) was 7.8 months. Multivariate analysis found a strong negative impact on outcome of MYC expression, TP53 mutation, STAT5B mutation and poor performance status while aberrant B-cell marker expression (20% of cases) correlated with better survival. In conclusion, MEITL is an aggressive disease with resistance to conventional therapy, predominantly characterized by driver gene alterations deregulating histone methylation and JAK/STAT signaling and encompasses genetic and morphologic variants associated with very high clinical risk.

Monocyte Signature Associated with Herpes Simplex Virus Reactivation and Neurological Recovery after Brain Injury.

Rationale: Brain injury induces systemic immunosuppression, increasing the risk of viral reactivations and altering neurological recovery. Objectives: To determine if systemic immune alterations and lung replication of herpesviridae are associated and can help predict outcomes after brain injury. Methods: We collected peripheral blood mononuclear cells in patients with severe brain injury requiring invasive mechanical ventilation. We systematically searched for respiratory herpes simplex virus (HSV) replications in tracheal aspirates. We also performed chromatin immunoprecipitation sequencing, RNA-sequencing, and in vitro functional assays of monocytes and CD4 T cells collected on Day 1 to characterize the immune response to severe acute brain injury. The primary outcome was the Glasgow Outcome Scale Extended at 6 months. Measurements and Main Results: In 344 patients with severe brain injury, lung HSV reactivations were observed in 39% of the 232 patients seropositive for HSV and independently associated with poor neurological recovery at 6 months (hazard ratio, 1.90; 95% confidence interval, 1.08-3.57). Weighted gene coexpression network analyses of the transcriptomic response of monocytes to brain injury defined a module of 721 genes, including PD-L1 and CD80, enriched for the binding DNA motif of the transcriptional factor Zeb2 and whose ontogenic analyses revealed decreased IFN-γ-mediated and antiviral response signaling pathways. This monocyte signature was preserved in a validation cohort and predicted the neurological outcome at 6 months with good accuracy (area under the curve, 0.786; 95% confidence interval, 0.593-0.978). Conclusions: A specific monocyte signature is associated with HSV reactivation and predicts poor recovery after brain injury. The alterations of the immune control of herpesviridae replication are understudied and represent a novel therapeutic target.

Efficacy of imiquimod in the management of lentigo maligna.

BACKGROUND: Lentigo maligna (LM) is a melanocytic proliferation occurring on photo-exposed skin that may progress to LM melanoma. Surgery is recommended as first-line treatment. Excision margins of 5-10 mm remain, without international consensus. Several studies have shown that imiquimod, an immunomodulator, induces LM regression. This study investigated the effect of imiquimod versus placebo in neoadjuvant settings. PATIENTS AND METHODS: We performed a prospective, randomized, multicentre, phase III clinical study. Patients were randomly assigned in 1:1 ratio to receive imiquimod or placebo for 4 weeks, followed by LM excision 4 weeks after the last application of imiquimod or placebo. The primary endpoint was extra-lesional excision, with a 5 mm margin from the residual pigmentation after imiquimod or vehicle. Secondary endpoints included the gain on the surface removed between the two groups; number of revision surgeries to obtain extra-lesional excisions; relapse-free time; and number of complete remissions after treatment. RESULTS: A total of 283 patients participated in this study; 247 patients, 121 patients in the placebo group and 126 in the imiquimod group, accounted for the modified ITT population. The first extralesional extirpation was performed in 116 (92%) imiquimod patients and in 102 (84%) placebo patients; the difference was not significant (p = 0.0743). Regarding the surface of LM, imiquimod reduced the LM surface (4.6-3.1 cm2 ) significantly (p < 0.001) more compared to the placebo (3.9-4.1 cm2 ). CONCLUSION: Imiquimod reduces the lentigo maligna surface after 1 month of treatment, without a higher risk of intralesional excision and with a positive aesthetic outcome.

Nodal cytotoxic peripheral T-cell lymphoma occurs frequently in the clinical setting of immunodysregulation and is associated with recurrent epigenetic alterations.

Nodal peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) with cytotoxic phenotype is overall rare, with most reports coming from Asia. Given its elusive pathobiology, we undertook a clinicopathological and molecular study of 54 Western patients diagnosed with PTCL, NOS expressing cytotoxic molecules, within a lymph node. More commonly males (M/F-2,6/1) with median age of 60 years were affected. Besides lymphadenopathy, 87% of patients had ≥1 involved extranodal site. High-stage disease (III-IV), International Prognostic Index >2, B symptoms, LDH level, and cytopenia(s) were observed in 92, 63, 67, 78, and 66% of cases, respectively. Ten patients had a history of B-cell malignancies, one each of myeloid neoplasm, breast or prostate cancer, and 4 others had underlying immune disorders. Most patients (70%) died, mostly of disease, with a median overall survival of 12.7 months. Immunophenotypically, the neoplastic lymphocytes were T-cell receptor (TCR) αß + (47%), TCR-silent (44%) or TCRγδ+ (10%), commonly CD8 + (45%) or CD4-CD8- (32%). All except one had an activated cytotoxic profile, and 95% were subclassified into PTCL-TBX21 subtype based on CXCR3, TBX21, and GATA3 expression pattern. Seven patients (13%) disclosed EBER + tumor cells. Targeted DNA deep-sequencing (33 cases) and multiplex ligation-dependent reverse transcription-polymerase chain reaction assay (43 cases) identified frequent mutations in epigenetic modifiers (73%), including TET2 (61%) and DNMT3A (39%), recurrent alterations affecting the TCR (36%) and JAK/STAT (24%) signaling pathways and TP53 mutations (18%). Fusion transcripts involving VAV1 were identified in 6/43 patients (14%). Patients with nodal cytotoxic PTCL, NOS have an aggressive behavior and frequently present in a background of impaired immunity, although the association with Epstein-Barr virus is rare. The recurrent alterations in genes involved in DNA methylation together with genes related to cytokine or TCR signaling, suggest that co-operation of epigenetic modulation with cell-signaling pathways plays a critical role in the pathogeny of these lymphomas.

Change in lentigo maligna score assessed by in vivo reflectance confocal microscopy after 1 month of imiquimod treatment for lentigo maligna management.

BACKGROUND: Treatment of lentigo maligna (LM) is challenging because of the potential functional and esthetic surgical sequelae. Imiquimod has been proposed as a treatment for LM. Reflectance confocal microscopy (RCM) is a noninvasive method for the diagnosis of LM and margin assessment. OBJECTIVES: To compare the overall LM score (LMS) assessed by RCM before and 1 month after the start of imiquimod treatment compared to placebo and to define the immunohistochemical (IHC) profile of responders to imiquimod. METHODS: A controlled randomized study was conducted. Forty patients underwent RCM examination with calculation of the LMS at baseline and after 1 month of treatment. An IHC analysis of excised tissues was performed. RESULTS: The 1-month LMS was significantly lower in patients treated with imiquimod compared to those treated with placebo (P < .001). The criteria in the imiquimod-treated patients that demonstrated significant decrease were nonedged papillae; large, round pagetoid cells; atypical cells at the dermoepidermal junction; and follicular location of atypical cells. IHC analysis showed a higher level of interferon gamma in the resected specimens of patients responding to imiquimod (P = .04). LIMITATIONS: Sample size was small. CONCLUSION: Assessing the LMS by RCM was useful to monitor LM response to imiquimod accurately.

Full-field optical coherence tomography: novel imaging technique for extemporaneous high-resolution analysis of mucosal architecture in human gut biopsies.

Full-field optical coherence tomography (FFOCT) is an imaging technique of biological tissue based on tissue light reflectance analysis. We evaluated the feasibility of imaging fresh digestive mucosal biopsies after a quick mounting procedure (5 min) using two distinct modalities of FFOCT. In static FFOCT mode, we gained high-resolution images of general gut tissue-specific architecture, such as oesophageal papillae, gastric pits, duodenal villi and colonic crypts. In dynamic FFOCT mode, we imaged individual epithelial cells of the mucosal lining with a cellular or subcellular resolution and identified cellular components of the lamina propria. FFOCT represents a promising dye-free imaging tool for on-site analysis of gut tissue remodelling.

Diagnosis and prognosis are supported by integrated assessment of next-generation sequencing in chronic myeloid malignancies. A real-life study.

Next-generation sequencing (NGS) is used to investigate the presence of somatic mutations. The utility of incorporating routine sequencing to guide diagnosis and therapeutic decisions remains unclear. We report the findings of an observational, multicenter study that aimed to assess the impact of somatic mutation testing by NGS in a reallife setting of chronic myeloid malignancies. A total of 177 patients were enrolled, partitioned into two overlapping groups. In group A (n=94), the indication was to search for clonal hematopoiesis, in a context of suspected myelodysplastic syndrome or myeloproliferative neoplasia. In group B (n=95), the theranostic impact of somatic mutations was studied. A panel of 34 genes was used on DNA extracted from blood or bone marrow samples. Within group A, the detection of clonal hematopoiesis supported the diagnosis of chronic myeloid malignancies for 31 patients while the absence of clonal hematopoiesis ruled out the suspected diagnosis in 47 patients. Within group B, NGS identified prognostically relevant somatic mutations in 32 patients, which had a therapeutic impact in 18 cases. By determining the presence or absence of somatic mutations, the application of NGS in daily practice was found to be useful for an integrated final diagnosis in 83% of the patients. Moreover, the search for somatic mutations had a prognostic impact that led to treatment modification in 19% of the cases. This study outlines the fact that adequate implementation of new investigations may have a significant positive medico-economic impact by enabling appropriate management of patients.

The inhibitory receptor CD94/NKG2A on CD8+ tumor-infiltrating lymphocytes in colorectal cancer: a promising new druggable immune checkpoint in the context of HLAE/ß2m overexpression.

We previously demonstrated that HLA-E/ß2m overexpression by tumor cells in colorectal cancers is associated with an unfavorable prognosis. However, the expression of its specific receptor CD94/NKG2 by intraepithelial tumor-infiltrating lymphocytes, their exact phenotype and function, as well as the relation with the molecular status of colorectal cancer and prognosis remain unknown. Based on a retrospective cohort of 234 colorectal cancer patients, we assessed the expression of HLA-E, ß2m, CD94, CD8, and NKp46 by immunohistochemistry on tissue microarray. The expression profile of HLA-E/ß2m on tumor cells and the density of tumor-infiltrating lymphocytes were correlated to the clinicopathological and molecular features (Microsatellite status, BRAF and RAS mutations). Then, from the primary tumors of 27 prospective colorectal cancers, we characterized by multiparameter flow cytometry the nature (T and/or NK cells) and the co-expression of the inhibitory NKG2A or activating NKG2C chain of ex vivo isolated CD94+ tumor-infiltrating lymphocytes. Their biological function was determined using an in vitro redirected cytolytic activity assay. Our results showed that HLA-E/ß2m was preferentially overexpressed in microsatellite instable tumors compared with microsatellite stable ones (45% vs. 19%, respectively, p = 0.0001), irrespective of the RAS or BRAF mutational status. However, HLA-E/ß2m+ colorectal cancers were significantly enriched in CD94+ intraepithelial tumor-infiltrating lymphocytes in microsatellite instable as well as in microsatellite stable tumors. Those CD94+ tumor-infiltrating lymphocytes mostly corresponded to CD8+ αß T cells, and  to a lesser extent to NK cells, and mainly co-expressed a functional inhibitory NKG2A chain. Finally, a high number of CD94+ intraepithelial tumor-infiltrating lymphocytes in close contact with tumor cells was independently associated with a worse overall survival. In conclusion, these findings strongly suggest that HLA-E/ß2m-CD94/NKG2A represents a new druggable inhibitory immune checkpoint, preferentially expressed in microsatellite instable tumors, but also in a subgroup of microsatellite stable tumors, leading to a new opportunity in colorectal cancer immunotherapies.

Defining signatures of peripheral T-cell lymphoma with a targeted 20-marker gene expression profiling assay.

Peripheral T-cell lymphoma comprises a heterogeneous group of mature non-Hodgkin lymphomas. Their diagnosis is challenging, with up to 30% of cases remaining unclassifiable and referred to as "not otherwise specified". We developed a reverse transcriptase-multiplex ligation-dependent probe amplification gene expression profiling assay to differentiate the main T-cell lymphoma entities and to study the heterogeneity of the "not specified" category. The test evaluates the expression of 20 genes, including 17 markers relevant to T-cell immunology and lymphoma biopathology, one Epstein-Barr virus-related transcript, and variants of RHOA (G17V) and IDH2 (R172K/T). By unsupervised hierarchical clustering, our assay accurately identified 21 of 21 ALK-positive anaplastic large cell lymphomas, 16 of 16 extranodal natural killer (NK)/T-cell lymphomas, 6 of 6 hepatosplenic T-cell lymphomas, and 13 of 13 adult T-cell leukemia/lymphomas. ALK-negative anaplastic lymphomas (n=34) segregated into one cytotoxic cluster (n=10) and one non-cytotoxic cluster expressing Th2 markers (n=24) and enriched in DUSP22-rearranged cases. The 63 TFH-derived lymphomas divided into two subgroups according to a predominant TFH (n=50) or an enrichment in Th2 (n=13) signatures. We next developed a support vector machine predictor which attributed a molecular class to 27 of 77 not specified T-cell lymphomas: 17 TFH, five cytotoxic ALK-negative anaplastic and five NK/T-cell lymphomas. Among the remaining cases, we identified two cell-of-origin subgroups corresponding to cytotoxic/Th1 (n=19) and Th2 (n=24) signatures. A reproducibility test on 40 cases yielded a 90% concordance between three independent laboratories. This study demonstrates the applicability of a simple gene expression assay for the classification of peripheral T-cell lymphomas. Its applicability to routinely-fixed samples makes it an attractive adjunct in diagnostic practice.

Progression of disease within 2 years (POD24) is a clinically relevant endpoint to identify high-risk follicular lymphoma patients in real life.

Follicular lymphoma (FL) is an indolent non-Hodgkin's lymphoma with heterogeneous outcomes. Progression or relapse of FL within 2 years (so-called POD24) after diagnosis is associated with a poor outcome for patients treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, prednisone) in clinical trials. POD24 needs further validation before it can be used as a relevant endpoint to assess treatment efficacy. In the present retrospective monocentric study, we investigated the predictive value of POD24 in a cohort of grade 1, 2, or 3a FL patients treated in our institution (Nantes Medical University, France) and registered in our local database. We investigated the nature of treatment lines, patients' outcomes, and the prognostic value of POD24. Between 2007 and 2016, 317 patients were included. After first-line therapy, 60 patients relapsed within 2 years (POD24-pos cohort), and 254 patients did not relapse within 2 years (PO24-neg cohort). Thirty-three patients died, and 34 patients had an aggressive transformation. The median follow-up is 59.9 months (1.6-395.5). The median PFS is 59.9 months. Overall survival (OS) at 1 year, 3 years, and 5 years is 98.4% [97.0-99.8], 95.1% [92.6-97.6], and 92.5% [89.3-95.9], respectively. The 5-year OS was statistically lower for POD24-pos patients (82% [71.9-93.5]) than for POD24-neg patients (93.3% [88.98-97.8]) (p = 10-5). In multivariate analyses, transformation was predictive of OS, and PS (≥ 1) was predictive of POD24. POD24 is predictive of a worse OS and may be recommended as a relevant endpoint in clinical trials and in real life in particular for patients with advanced disease.

Expression of CCR6 and CXCR6 by Gut-Derived CD4+/CD8α+ T-Regulatory Cells, Which Are Decreased in Blood Samples From Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Faecalibacterium prausnitzii, a member of the Clostridium IV group of the Firmicutes phylum that is abundant in the intestinal microbiota, has anti-inflammatory effects. The relative level of F prausnitzii is decreased in fecal samples from patients with inflammatory bowel diseases (IBDs) compared with healthy individuals. Reduced F prausnitzii was correlated with relapse of Crohn's disease after surgery. We identified, in human colonic mucosa and blood, a population of T regulatory type 1-like T regulatory (TREG) cells that express CD4 and CD8α (DP8α T cells) and are specific for F prausnitzii. We aimed to determine whether they are altered in patients with IBD. METHODS: We isolated DP8α T cells from human colon lamina propria and blood samples and used flow cytometry to detect markers of cells that are of colon origin. We quantified DP8α cells that express colon-specific markers in blood samples from 106 patients with IBD, 12 patients with infectious colitis, and 35 healthy donors (controls). We identified cells that respond to F prausnitzii. Cells were stimulated with anti-CD3, and their production of interleukin 10 was measured by enzyme-linked immunosorbent assay. We compared the frequency and reactivity of cells from patients vs controls using the 2-sided Student t test or 1-way analysis of variance. RESULTS: Circulating DP8α T cells that proliferate in response to F prausnitzii express the C-C motif chemokine receptor 6 (CCR6) and C-X-C motif chemokine receptor 6 (CXCR6). These cells also have features of TREG cells, including production of IL-10 and inhibition of T-cell proliferation via CD39 activity. The proportion of circulating CCR6+/CXCR6+ DP8α T cells was significantly reduced (P < .0001) within the total population of CD3+ T cells from patients with IBD compared with patients with infectious colitis or controls. A threshold of <7.875 CCR6+/CXCR6+ DP8α T cells/10,000 CD3+ cells discriminated patients with IBD from those with infectious colitis with 100% specificity and 72.2% sensitivity. CONCLUSIONS: We identified a population of gut-derived TREG cells that are reduced in blood samples from patients with IBD compared with patients with infectious colitis or controls. These cells should be studied further to determine the mechanisms of this reduction and how it might contribute to the pathogenesis of IBD and their prognostic or diagnostic value.

CD4CD8αα lymphocytes, a novel human regulatory T cell subset induced by colonic bacteria and deficient in patients with inflammatory bowel disease.

How the microbiota affects health and disease is a crucial question. In mice, gut Clostridium bacteria are potent inducers of colonic interleukin (IL)-10-producing Foxp3 regulatory T cells (Treg), which play key roles in the prevention of colitis and in systemic immunity. In humans, although gut microbiota dysbiosis is associated with immune disorders, the underlying mechanism remains unknown. In contrast with mice, the contribution of Foxp3 Treg in colitis prevention has been questioned, suggesting that other compensatory regulatory cells or mechanisms may exist. Here we addressed the regulatory role of the CD4CD8 T cells whose presence had been reported in the intestinal mucosa and blood. Using colonic lamina propria lymphocytes (LPL) and peripheral blood lymphocytes (PBL) from healthy individuals, and those with colon cancer and irritable bowel disease (IBD), we demonstrated that CD4CD8αα (DP8α) T lymphocytes expressed most of the regulatory markers and functions of Foxp3 Treg and secreted IL-10. Strikingly, DP8α LPL and PBL exhibited a highly skewed repertoire toward the recognition of Faecalibacterium prausnitzii, a major Clostridium species of the human gut microbiota, which is decreased in patients with IBD. Furthermore, the frequencies of DP8α PBL and colonic LPL were lower in patients with IBD than in healthy donors and in the healthy mucosa of patients with colon cancer, respectively. Moreover, PBL and LPL from most patients with active IBD failed to respond to F. prausnitzii in contrast to PBL and LPL from patients in remission and/or healthy donors. These data (i) uncover a Clostridium-specific IL-10-secreting Treg subset present in the human colonic LP and blood, (ii) identify F. prausnitzii as a major inducer of these Treg, (iii) argue that these cells contribute to the control or prevention of colitis, opening new diagnostic and therapeutic strategies for IBD, and (iv) provide new tools to address the systemic impact of both these Treg and the intestinal microbiota on the human immune homeostasis.

Clinical, Genetic and Innate Immunity Characteristics of Melanoma in Organ Transplant Recipients.

The aims of this study were to determine the clinical and histological characteristics of melanoma in transplant recipients, the mutation profile (BRAF, NRAS and c-KIT genes), and the immune tolerance of the tumour microenvironment by immunohistochemical study of the expression of indoleamine 2,3-dioxygenase (IDO), PD1, PD-L1, CD8 and FoxP3. The study population comprised patients who had undergone a renal transplant in Nantes University Hospital who developed post-transplantation melanoma. Twenty cases of melanoma out of 4,663 transplant recipients were studied. The results differed from the usual data with respect to melanoma site: 40% were located on the face and were of the malignant lentigo type. The mutation profile was concordant with that of the immunocompetent population. IDO was expressed in all the sections tested, while CD8, FoxP3, PD1 and PD-L1 were poorly expressed. This reflected a highly immunodepressed tumour environment, raising the question of the inductive role of IDO on tumour immune tolerance in patients presenting with long-term immunodepression.

Immunohistochemistry as a valuable tool to assess CD30 expression in peripheral T-cell lymphomas: high correlation with mRNA levels.

The extended use of brentuximab-vedotin was reported for CD30(+) nonanaplastic peripheral T-cell lymphomas (PTCLs) with promising efficacy. CD30 status assessment is thus a critical factor for therapeutic decision, but the reliability of immunohistochemistry (IHC) in evaluating its expression remains to be defined. This prompted us to investigate the correlation between semiquantitative CD30 protein assessment by IHC and messenger RNA (mRNA) assessment by microarrays in a cohort of 376 noncutaneous PTCLs representative of the main entities. By IHC, CD30 expression was heterogeneous across and within entities and significantly associated with large tumor cell size. In addition to 100% anaplastic large-cell lymphomas, 57% of other PTCL entities were CD30-positive at a 5% threshold. CD30 protein expression was highly correlated to mRNA levels. mRNA levels were bimodal, separating high from low CD30-expressing PTCL cases. We conclude that IHC is a valuable tool in clinical practice to assess CD30 expression in PTCLs.

Heterogeneity of subordination of the IL-18/IFN-γ axis to caspase-1 among patients with Crohn's disease.

In Crohn's disease (CD), hierarchical architecture of the inflammatory network, including subordination of IL-18, an IFN-γ-inducing cytokine, to the inflammasome, have remained undeciphered. Heterogeneity among patients of such a subordination cannot be evaluated by animal models, monofactorial in their etiology and homogenous in disease progression. To address these issues, we set up an ex vivo model of inflamed mucosa explant cultures from patients with active long-standing CD. Th1 cytokine production, especially IFN-γ and IL-18, was assessed in relation with inflammation intensity. Subordination of the Th1 response to caspase-1, effector of the inflammasome, was determined in explant cultures subjected to pharmacological inhibition of caspase-1 by YVAD. We showed a correlation between secreted IFN-γ/IL-18 levels, and caspase-1 activation, with inflammation intensity of intestinal CD mucosa explants. Inhibition of caspase-1 activation using the specific inhibitor YVAD identified a homogenous non responder group featuring a caspase-1-independent IL-18/IFN-γ response, and a heterogenous responder group, in which both IL-18 and IFN-γ responses were caspase-1-dependent, with a 40-70% range of inhibition by YVAD. These findings bring out the concept of heterogeneity of subordination of the Th1 response to inflammasome activation among CD patients. This ex vivo model should have therapeutic relevance in allowing to determine eligibility of CD patients for new targeted therapies.

Improvement of Refractory Ulcerative Proctitis With Sacral Nerve Stimulation.

BACKGROUND AND AIMS: Sacral nerve stimulation (SNS) is recognized for its efficiency and safety for anal incontinence, preventing high morbidity. Evidence from the literature suggests extending SNS to diseases associated with problems of intestinal barrier permeability. The aim of this study was to highlight clinical evidence of the beneficial impact of SNS in a refractory proctitis case report. MATERIALS AND METHODS: A permanent SNS was performed successfully in a patient with proctitis after implantation of the neuromodulator. Despite immunosuppressive drugs, the patient was experiencing mucus and blood discharge, pain, and fecal incontinence. To relieve fecal incontinence, SNS was tested without modification of medications. Disease activity, endoscopic and histologic score, ex vivo barrier permeability, expression of inflammatory cytokines (transforming growth factor-ß, tumor necrosis factor α, Interleukin-6, Interleukin-8), and junctional proteins (ZO-1, claudin-1, occludin) were assessed before and after SNS to observe the impact of SNS other than for incontinence. RESULTS: After a 3-week period of temporary stimulation, the patient experienced significant improvement with a decrease in fecal incontinence and disease activity scores. Both endoscopic and histologic scores showed improvement. The rectal barrier permeability decreased with SNS, whereas junctional protein mRNA expression transiently increased. Clinical and histologic improvement was sustained over time. After 18 months of permanent stimulation, the patient remained improved by SNS. CONCLUSION: This work demonstrates the relevance to explore further indications of SNS beyond fecal incontinence.

Confocal laser endomicroscopy: a new gold standard for the assessment of mucosal healing in ulcerative colitis.

BACKGROUND AND AIM: Endoscopic assessment of mucosal healing in ulcerative colitis (UC) is increasingly accepted as a measure of disease activity, therapeutic goal, and the key prognostic indicator. While regular endoscopy evaluates appearance of the mucosal surface, confocal laser endomicroscopy (CLE) enables in vivo visualization of subepithelial mucosa at 1000× magnification during ongoing endoscopy. Our aims were to determine using CLE whether endoscopically normal appearing colonic mucosa in patients with UC in remission (UC-IR) has fully regenerated mucosal structures, resolved inflammation, and to identify the mechanisms. METHODS: Twelve patients (six controls and six with UC-IR) underwent colonoscopy using CLE and intravenous fluorescein infusion. During colonoscopy, CLE images of colonic mucosa and conventional mucosal biopsies were obtained and evaluated using image-analysis systems. We quantified; (i) regeneration of colonic crypts and blood microvessels; (ii) cyclooxygenase 2 (COX2) expression; (iii) mitochondrial DNA (mtDNA) mutations; (iv) inflammatory infiltration; and (v) vascular permeability (VP). RESULTS: In control subjects, CLE demonstrated normal colonic crypts and microvasculature. COX2 expression was minimal, and < 7% crypts showed mtDNA mutations. Colonic mucosa of UC-IR patients had impaired and distorted crypt regeneration, increased COX2, 69% crypts with mtDNA mutations, persistent inflammation, and abnormal vascular architecture with increased VP (all P < 0.001 vs normal mucosa). CONCLUSIONS: (i) Endoscopically normal appearing colonic mucosa of patients with UC-IR remains abnormal: CLE demonstrates impaired crypt regeneration, persistent inflammation, distinct abnormalities in angioarchitecture and increased vascular permeability; molecular imaging showed increased COX2 and mtDNA mutations; (ii) CLE may serve as a new gold standard for the assessment of mucosal healing in UC.