Neu1 deficiency and fibrotic lymph node microenvironment lead to imbalance in M1/M2 macrophage polarization.

Macrophages play a pivotal role in tissue homeostasis, pathogen defense, and inflammation resolution. M1 and M2 macrophage phenotypes represent two faces in a spectrum of responses to microenvironmental changes, crucial in both physiological and pathological conditions. Neuraminidase 1 (Neu1), a lysosomal and cell surface sialidase responsible for removing terminal sialic acid residues from glycoconjugates, modulates several macrophage functions, including phagocytosis and Toll-like receptor (TLR) signaling. Current evidence suggests that Neu1 expression influences M1/M2 macrophage phenotype alterations in the context of cardiovascular diseases, indicating a potential role for Neu1 in macrophage polarization. For this reason, we investigated the impact of Neu1 deficiency on macrophage polarization in vitro and in vivo. Using bone marrow-derived macrophages (BMDMs) and peritoneal macrophages from Neu1 knockout (Neu1-/- ) mice and wild-type (WT) littermate controls, we demonstrated that Neu1-deficient macrophages exhibit an aberrant M2-like phenotype, characterized by elevated macrophage mannose receptor 1 (MMR/CD206) expression and reduced responsiveness to M1 stimuli. This M2-like phenotype was also observed in vivo in peritoneal and splenic macrophages. However, lymph node (LN) macrophages from Neu1-/- mice exhibited phenotypic alterations with reduced CD206 expression. Further analysis revealed that peripheral LNs from Neu1-/- mice were highly fibrotic, with overexpression of transforming growth factor-beta 1 (TGF-ß1) and hyperactivated TGF-ß signaling in LN macrophages. Consistently, TGF-ß1 was found to alter M1/M2 macrophage polarization in vitro. Our findings showed that Neu1 deficiency prompts macrophages towards an M2 phenotype and that microenvironmental changes, particularly increased TGF-ß1 in fibrotic tissues such as peripheral LNs in Neu1-/- mice, further influence M1/M2 macrophage polarization, highlighting its sensitivity to the local microenvironment. Therapeutic interventions targeting Neu1 or TGF-ß signaling pathways may offer the potential to regulate macrophage behavior across different diseases.

Low EGFL7 expression is associated with high lymph node spread and invasion of lymphatic vessels in colorectal cancer.

Studies indicate EGFL7 as an important gene in controlling angiogenesis and cancer growth, including in colorectal cancer (CRC). Anti-EGFL7 agents are being explored, yet without promising results. Therefore, the role of EGFL7 in CRC carcinogenesis should be investigated. This study aimed to evaluate the prognostic value of EGFL7 expression in CRC and the signaling pathways influenced by this gene. EGFL7 expression was evaluated through immunohistochemistry in 463 patients diagnosed with CRC and further associated with clinicopathological data, angiogenesis markers and survival. In silico analyzes were performed with colon adenocarcinoma data from The Cancer Genome Atlas. Analysis of enriched gene ontology and pathways were performed using the differentially expressed genes. 77.7% of patients presented low EGFL7 expression, which was associated with higher lymph node spread and invasion of lymphatic vessels, with no impact on survival. Additionally, low EGFL7 expression was associated with high VEGFR2 expression. Finally, we found in silico that EGFL7 expression was associated with cell growth, angiogenesis, and important pathways such as VEGF, Rap-1, MAPK and PI3K/Akt. Expression of EGFL7 in tumor cells may be associated with important pathways that can alter functions related to tumor invasive processes, preventing recurrence and metastatic process.

Trop-2 Is Highly Expressed in Early Luminal-Like Breast Cancer.

Trop-2, a transmembrane glycoprotein, has been identified in human epithelial cells as a contributor to tumor growth and unfavorable prognosis in breast cancer (BC). Our study aimed to assess the expression of Trop-2 protein via immunohistochemistry (IHC) and correlate it with clinicopathological features in early luminal-like BC. We conducted a cross-sectional study evaluating Trop-2 protein expression in tissue microarrays using IHC. The expression was evaluated by the H-score and the following categorization was used: H-Score 0 to <100 as low, H-Score 100 to 200 as intermediate, and H-Score >200 to 300 as high. The study included 84 patients with a median age of 57, of whom 70% had invasive ductal carcinomas, 75% were classified as T2, and 47.6% had no affected lymph nodes. Trop-2 expression was high in 56% of patients and intermediate in 38%. None of the patients had an H-Score of zero. No correlation was observed between Trop-2 expression and clinicopathological features, including age, histological subtype, grade, Ki67, tumor size, nodal status, lymphovascular invasion, tumor subtype, and pathological staging. We demonstrated that Trop-2 is highly expressed in early luminal-like BC and is not influenced by clinicopathological features.

Dopaminergic Receptors as Neuroimmune Mediators in Experimental Autoimmune Encephalomyelitis.

The dopaminergic system plays an essential role in maintaining homeostasis between the central nervous system (CNS) and the immune system. Previous studies have associated imbalances in the dopaminergic system to the pathogenesis of multiple sclerosis (MS). Here, we examined the protein levels of dopaminergic receptors (D1R and D2R) in different phases of the experimental autoimmune encephalomyelitis (EAE) model. We also investigated if the treatment with pramipexole (PPX)-a dopamine D2/D3 receptor-preferring agonist-would be able to prevent EAE-induced motor and mood dysfunction, as well as its underlying mechanisms of action. We report that D2R immunocontent is upregulated in the spinal cord of EAE mice 14 days post-induction. Moreover, D1R and D2R immunocontents in lymph nodes and the oxidative damage in the spinal cord and striatum of EAE animals were significantly increased during the chronic phase. Also, during the pre-symptomatic phase, axonal damage in the spinal cord of EAE mice could already be found. Surprisingly, therapeutic treatment with PPX failed to inhibit the progression of EAE. Of note, PPX treatment inhibited EAE-induced depressive-like while failed to inhibit anhedonic-like behaviors. We observed that PPX treatment downregulated IL-1ß levels and increased BNDF content in the spinal cord after EAE induction. Herein, we show that a D2/D3 receptor-preferred agonist mitigated EAE-induced depressive-like behavior, which could serve as a new possibility for further clinical trials on treating depressive symptoms in MS patients. Thus, we infer that D2R participates in the crosstalk between CNS and immune system during autoimmune and neuroinflammatory response induced by EAE, mainly in the acute and chronic phase of the disease.

Distinct kinetics for nucleotide hydrolysis in lymphocytes isolated from blood, spleen and cervical lymph nodes: Characterization of ectonucleotidase activity.

Ectonucleotidases are a plasma membrane-bound enzyme that hydrolyses extracellular adenosine triphosphate (eATP) and adenosine diphosphate (eADP) to adenosine monophosphate (AMP). It regulates normal function of lymphocytes, acts as an inflammatory marker and represents a molecular target for new therapeutics. Thus, this study sought to isolate lymphocytes from blood (BL), spleen (SL) and cervical lymph node (CLL), and characterize the eATP and eADP enzymatic hydrolysis in Wistar rats. The hydrolysis of the nucleotides occurred primarily at pH 8.0, 37°C in the presence of Ca2+ or Mg2+ . Chevillard-plot showed the hydrolysis of eATP and eADP at the same active site. The inhibitors of some classical ATDPases did not cause any significant change on enzymatic activity. Inhibitors of E-NTPDase (-1, -2, -3 isoforms) and E-NPP-1 decrease the enzyme activity in all resident lymphocytes. Furthermore, kinetic parameters (Vmax and Km) revealed that SL had significantly (P < .001) higher enzymatic activity when compared to BL and CLL. In conclusion, this study standardized kinetic values for eATP and eADP hydrolysis for resident lymphocytes isolated from BL, SL and CLL.

Systems Biology Analysis of the Radiation-Attenuated Schistosome Vaccine Reveals a Role for Growth Factors in Protection and Hemostasis Inhibition in Parasite Survival.

In spite of several decades of research, an effective vaccine against schistosomiasis remains elusive. The radiation-attenuated (RA) cercarial vaccine is still the best model eliciting high protection levels, although the immune mechanisms have not yet been fully characterized. In order to identify genes and pathways underlying protection we investigated patterns of gene expression in PBMC and skin draining Lymph Nodes (LN) from mice using two exposure comparisons: vaccination with 500 attenuated cercariae versus infection with 500 normal cercariae; one versus three doses. Vaccinated mice were challenged with 120 normal parasites. Integration of PBMC and LN data from the infected group revealed early up-regulation of pathways associated with Th2 skewing and polarization of IgG antibody profiles. Additionally, hemostasis pathways were downregulated in infected mice, correlating with platelet reduction, potentially a mechanism to assist parasite migration through capillary beds. Conversely, up regulation of such mechanisms after vaccination may explain parasite blockade in the lungs. In contrast, a single exposure to attenuated parasites revealed early establishment of a Th1 bias (signaling of IL-1, IFN-γ; and Leishmania infection). Genes encoding chemokines and their receptors were more prominent in vaccinated mice, indicating an enhanced capacity for inflammation, potentially augmenting the inhibition of intravascular migration. Increasing the vaccinations from one to three did not dramatically elevate protection, but there was a clear shift towards antibody-mediated effectors. However, elements of the Th1 bias were still evident. Notable features after three vaccinations were markers of cytotoxicity (including IL-6 and NK cells) together with growth factors and their receptors (FGFR/VEGF/EGF) and the apoptosis pathway. Indeed, there is evidence for the development of anergy after three vaccinations, borne out by the limited responses detected in samples after challenge. We infer that persistence of a Th1 response puts a limit on expression of antibody-mediated mechanisms. This feature may explain the failure of multiple doses to drive protection towards sterile immunity. We suggest that the secretions of lung stage parasites would make a novel cohort of antigens for testing in protection experiments.

Analysis of the Immunoexpression of Opioid Receptors and their Correlation with Markers of Angiogenesis, Cell Proliferation and Apoptosis in Breast Cancer.

OBJECTIVE: Breast cancer is a disease of great concern. The prognosis of this tumor is related to its staging. Opioids are widely used to minimize pain in oncology clinics; however, the relationship between the administration of opioids and their effects on tumor cells has yet to be elucidated. Therefore, this study aimed to evaluate the immunoexpression of mu- (µ) and kappa- (κ) opioid receptors and their correlation with markers of angiogenesis, cell proliferation, and apoptosis in biopsies of breast tumors. METHODS: Demographic data, tumor characteristics, opioid use, and prognostic factors were collected from medical records. After the selection of the excisional biopsies, immunohistochemistry was performed for µ- and κ-opioid receptors, vascular endothelial growth factor (VEGF), Ki-67, and TUNEL. RESULTS: A significant predominance of Ki-67 and µ-opioid receptor immunoexpression in the lymph nodes was observed in patients administered opioid medications. The luminal A subtype showed higher apoptosis levels (TUNEL) compared to the luminal B subtype. Patients with T4 tumor who had recurrence demonstrated a reduced expression of κ-opioid receptors at the lymph node location. Correlation analyses between the µ and κ opioid markers, VEGF, Ki-67, and TUNEL showed that these findings are likely involved in the same mechanisms the cancer of T4 stage breast cancer. CONCLUSION: The κ-opioid receptor has a lower immunoexpression in nodal tumor metastasis with recurrence, whereas the µ-opioid receptor is directly related to expression of TUNEL-positive cells  in tumors and indirectly to Ki-67 in nodal metastasis. Neither of the two receptors was expressed in the primary tumor or nodal metastasis in relation to VEGF.

Pitavastatin ameliorates autoimmune neuroinflammation by regulating the Treg/Th17 cell balance through inhibition of mevalonate metabolism.

While Treg cells are responsible for self-tolerance and immune homeostasis, pathogenic autoreactive Th17 cells produce pro-inflammatory cytokines that lead to tissue damage associated with autoimmunity, as observed in multiple sclerosis. Therefore, the immunological balance between Th17 and Treg cells may represent a promising option for immune therapy. Statin drugs are used to treat dyslipidemia; however, besides their effects on preventing cardiovascular diseases, statins also have anti-inflammatory effects. Here, we investigated the role of pitavastatin on experimental autoimmune encephalomyelitis (EAE) and the differentiation of Treg and Th17 cells. EAE was induced by immunizing C57BL/6 mice with MOG35-55. EAE severity was determined by analyzing the clinical score and inflammatory parameters in the spinal cord. Naive CD4 T cells were cultured under Treg and Th17-skewing conditions in vitro in the presence of pitavastatin. We found that pitavastatin decreased EAE development, which was accompanied by a reduction of all parameters investigated. Pitavastatin also reduced the expression of IBA1 and pSTAT3 (Y705 and S727) in the spinal cords of EAE mice. Interestingly, the reduction of Th17 cell frequency in the draining lymph nodes of EAE mice treated with pitavastatin was followed by an increase of Treg cells. Indeed, pitavastatin directly affects T cell differentiation in vitro by decreasing Th17 and increasing Treg cell differentiation. Mechanistically, pitavastatin effects are dependent on mevalonate synthesis. Thus, our data show the potential anti-inflammatory effect of pitavastatin on the pathogenesis of the experimental neuroinflammation by modulating the Th17/Treg axis.

CCNA1 gene as a potential diagnostic marker in papillary thyroid cancer.

The malignancy that most affects the endocrine system is thyroid neoplasm, with an increasing incidence over the years. The most prevalent histological type of the carcinomas that affect the thyroid gland is papillary carcinoma with a prevalence of 80 % worldwide. The current diagnostic methodology may present inconclusive results, emphasizing the need for new effective and sensitive techniques to aid the diagnosis. For this, it is necessary to understand molecular and protein mechanisms in the identification of diagnostic and predictive markers in the lesions. The Cyclin A1 protein, encoded by the CCNA1 gene, is an important cell cycle regulator, belonging to the MAPK/ERK signaling pathway directly involved with thyroid cancer. The aim of this study was to evaluate the CCNA1 gene and Cyclin A1 protein expression in papillary thyroid carcinoma, follicular thyroid carcinoma, and benign thyroid lesions, by real time quantitative PCR and immunohistochemistry analysis, respectively, to verify their roles as potential diagnostic and predictive markers to future applications in the clinical routine. Overexpression of CCNA1 gene was observed in the papillary carcinoma group compared to the normal group (P = 0.0023), benign lesions (P = 0.0011), colloid goiter (P = 0.0124), and follicular carcinoma (P = 0.0063). No differential expression was observed in the papillary primary tumor group from negative lymph nodes compared with the one from positive lymph nodes (P = 0.3818). Although an increased expression of Cyclin A1 was observed in the PTC group compared to the other one in the IHC analysis, no significant difference was observed (Fisher's exact Test). A Cyclin A1 overexpression was detected with weak to mid-moderate immunoreactivity in the benign group (k = 0.56), (score 1.5); mid-moderate to moderate in the goiter group (k = 0.58); weak in the FTC group (k = 0.33); and mid-moderate to moderate in the PTC group (k = 0.48). Due to the small sample size in the IHC analysis and to the fact that not all RNA is translated into protein, the diagnostic potential of Cyclin A1 could not be assessed. However, these findings highlight the potential of the CCNA1 gene as a diagnostic marker for papillary thyroid carcinoma.

Prognostic impact of Claudin 18.2 in gastric and esophageal adenocarcinomas.

INTRODUCTION: The tight junction molecule Claudin 18.2 is selectively expressed in healthy and malignant gastric epithelial tissue and is a promising therapy target for high Claudin 18.2 expressing adenocarcinomas of the esophagogastric junction and stomach (AEG/S). METHODS: This study analyzed the prevalence, characteristics and prognostic impact of Claudin 18.2 expression in primary tumor, lymph node and distant metastasis in a large Caucasian AGE/S cohort with 414 patients. RESULTS: Claudin 18.2 was highly expressed in 17.1% of primary tumors, 26.7% of lymph node metastasis and 16.7% of distant metastasis. High Claudin 18.2 expression in lymph node metastasis and primary tumors correlated significantly (p < 0.001). High expression of Claudin 18.2 was neither associated with histomorphogical subtype, or tumor state, nor with overall survival. CONCLUSION: In Caucasian AEG/S patients, 17.1% appeared to be eligible for an anti-Claudin 18.2 therapy. Claudin 18.2 expression itself has no impact on prognosis and is not related to any tumor subtype.

Blimp-1 is essential for allergen-induced asthma and Th2 cell development in the lung.

A Th2 immune response is central to allergic airway inflammation, which afflicts millions worldwide. However, the mechanisms that augment GATA3 expression in an antigen-primed developing Th2 cell are not well understood. Here, we describe an unexpected role for Blimp-1, a transcriptional repressor that constrains autoimmunity, as an upstream promoter of GATA3 expression that is critical for Th2 cell development in the lung to inhaled but not systemically delivered allergens but is dispensable for TFH function and IgE production. Mechanistically, Blimp-1 acts through Bcl6, leading to increased GATA3 expression in lung Th2 cells. Surprisingly, the anti-inflammatory cytokine IL-10, but not the pro-inflammatory cytokines IL-6 or IL-21, is required via STAT3 activation to up-regulate Blimp-1 and promote Th2 cell development. These data reveal a hitherto unappreciated role for an IL-10-STAT3-Blimp-1 circuit as an initiator of an inflammatory Th2 response in the lung to allergens. Thus, Blimp-1 in a context-dependent fashion can drive inflammation by promoting rather than terminating effector T cell responses.

Context-specific functions of Notch in Drosophila blood cell progenitors.

Drosophila Larval hematopoiesis takes place at the lymph gland, where myeloid-like progenitors differentiate into Plasmatocytes and Crystal Cells, under regulation of conserved signaling pathways. It has been established that the Notch pathway plays a specific role in Crystal Cell differentiation and maintenance. In mammalian hematopoiesis, the Notch pathway has been proposed to fulfill broader functions, including Hematopoietic Stem Cell maintenance and cell fate decision in progenitors. In this work we describe different roles that Notch plays in the lymph gland. We show that Notch, activated by its ligand Serrate, expressed at the Posterior Signaling Center, is required to restrain Core Progenitor differentiation. We define a novel population of blood cell progenitors that we name Distal Progenitors, where Notch, activated by Serrate expressed in Lineage Specifying Cells at the Medullary Zone/Cortical Zone boundary, regulates a binary decision between Plasmatocyte and Crystal Cell fates. Thus, Notch plays context-specific functions in different blood cell progenitor populations of the Drosophila lymph gland.

Myo1e modulates the recruitment of activated B cells to inguinal lymph nodes.

The inclusion of lymphocytes in high endothelial venules and their migration to the lymph nodes are critical steps in the immune response. Cell migration is regulated by the actin cytoskeleton and myosins. Myo1e is a long-tailed class I myosin and is highly expressed in B cells, which have not been studied in the context of cell migration. By using intravital microscopy in an in vivo model and performing in vitro experiments, we studied the relevance of Myo1e for the adhesion and inclusion of activated B cells in high endothelial venules. We observed reduced expression of integrins and F-actin in the membrane protrusions of B lymphocytes, which might be explained by deficiencies in vesicular trafficking. Interestingly, the lack of Myo1e reduced the phosphorylation of focal adhesion kinase (FAK; also known as PTK2), AKT (also known as AKT1) and RAC-1, disturbing the FAK-PI3K-RAC-1 signaling pathway. Taken together, our results indicate a critical role of Myo1e in the mechanism of B-cell adhesion and migration.

Role of indoleamine 2,3-dioxygenase in testicular immune-privilege.

Male meiotic germ cell including the spermatozoa represent a great challenge to the immune system, as they appear long after the establishment of normal immune tolerance mechanisms. The capacity of the testes to tolerate autoantigenic germ cells as well as survival of allogeneic organ engrafted in the testicular interstitium have led to consider the testis an immunologically privileged site. Disruption of this immune privilege following trauma, tumor, or autoimmune orchitis often results in male infertility. Strong evidence indicates that indoleamine 2,3-dioxygenase (IDO) has been implicated in fetal and allograft tolerance, tumor immune resistance, and regulation of autoimmune diseases. IDO and tryptophan 2,3-dioxygenase (TDO) catalyze the same rate-limiting step of tryptophan metabolism along a common pathway, which leads to tryptophan starvation and generation of catabolites collectively known as kynurenines. However, the relevance of tryptophan metabolism in testis pathophysiology has not yet been explored. Here we assessed the in vivo role of IDO/TDO in experimental autoimmune orchitis (EAO), a model of autoimmune testicular inflammation and immunologically impaired spermatogenesis. EAO was induced in adult Wistar rats with testicular homogenate and adjuvants. Control (C) rats injected with saline and adjuvants and normal untreated rats (N) were also studied. mRNA expression of IDO decreased in whole testes and in isolated Sertoli cells during EAO. TDO and IDO localization and level of expression in the testis were analyzed by immunostaining and Western blot. TDO is expressed in granulomas from EAO rats, and similar protein levels were observed in N, C, and EAO groups. IDO was detected in mononuclear and endothelial cells and reduced IDO expression was detected in EAO group compared to N and C rats. This phenomenon was concomitant with a significant reduction of IDO activity in EAO testis measured by tryptophan and kynurenine concentrations (HPLC). Finally, in vivo inhibition of IDO with 1-methyl-tryptophan increased severity of the disease, demonstrating down regulation of IDO-based tolerance when testicular immune regulation was disrupted. We present evidence that an IDO-based mechanism is involved in testicular immune privilege.

Obesity affects peripheral lymphoid organs immune response in murine asthma model.

Asthma and obesity present rising incidence, and their concomitance is a reason for concern, as obese individuals are usually resistant to conventional asthma treatments and have more exacerbation episodes. Obesity affects several features in the lungs during asthma onset, shifting the T helper type 2 (Th2)/eosinophilic response towards a Th17/neutrophilic profile. Moreover, those individuals can present reduced atopy and delayed cytokine production. However, the impact of obesity on follicular helper T (Tfh) cells and B cells that could potentially result in antibody production disturbances are still unclear. Therefore, we aimed to assess the peripheral response to ovalbumin (OVA) in a concomitant model of obesity and asthma. Pulmonary allergy was induced, in both lean and obese female BALB/c mice, through OVA sensitizations and challenges. Mediastinal lymph nodes (MLNs) and spleen were processed for immunophenotyping. Lung was used for standard allergy analysis. Obese-allergic mice produced less anti-OVA IgE and more IgG2a than lean-allergic mice. Dendritic cells (CD11c+  MHCIIhigh ) expressed less CD86 and more PDL1 in obese-allergic mice compared with lean-allergic mice, in the MLNs. Meanwhile, B cells (CD19+  CD40+ ) were more frequent and the amount of PDL1/PD1+ cells was diminished by obesity, with the opposite effects in the spleen. Tfh cells (CD3+  CD4+  CXCR5+  PD1+ ) expressing FoxP3 were more frequent in obese mice, associated with the predominance of Th (CD3+  CD4+ ) cells expressing interleukin-4/GATA3 in the MLNs and interleukin-17A/RORγT in the spleen. Those modifications to the main components of the germinal centers could be resulting in the increased IgG2a production, which - associated with the Th17/neutrophilic profile - contributes to asthma worsening and represents an important target for future treatment strategies.

Hypothyroidism-related zinc deficiency leads to suppression of T lymphocyte activity.

PURPOSE: Hypothyroidism has been shown to induce immunosuppression and both the thyroid status and immunity are affected by zinc deficiency. However, the impact of hypothyroidism on zinc metabolism and its possible relationship with the immune status has not yet been deeply explored. Here, our aim was to study whether hypothyroidism may alter zinc metabolism and thus lead to the impairment of T lymphocyte activity. METHODS: Variations in the distribution of zinc in the body were evaluated in PTU-treated hypothyroid mice. The effects of hypothyroidism and zinc deficiency were studied on T lymphocyte proliferation after stimulation both in vitro and in vivo. For in vitro assays, thyroid hormone-free or zinc chelator (TPEN or DTPA)-supplemented media were used. For in vivo assays, lymphocyte activity was evaluated in cells from hypothyroid, T3-treated, and zinc-supplemented mice. RESULTS: Hypothyroid mice showed lower levels of zinc in femur and lymph nodes than controls. T3 and zinc supplementation reversed these effects. In vitro, both thyroid hormone and zinc deficiency led to a decreased response to mitogen stimulation. However, only zinc deficiency was able to induce lymphocyte apoptosis. Mitogen-stimulated T cells from hypothyroid mice showed impaired proliferation, accompanied by decreased activation of PKC and lower levels of p-ERK, effects that were reversed by T3 replacement or zinc supplementation. CONCLUSIONS: Our results show an important role of zinc deficiency in hypothyroid-mediated T-cell suppression and suggest the importance of evaluating zinc levels and restoring them when necessary to maintain an efficient immune response in hypothyroid patients.

Nodal FDG-PET/CT uptake influences outcome and relapse location among esophageal cancer patients submitted to chemotherapy or radiochemotherapy.

PURPOSE: Our aim was investigate whether lymph node uptake is associated with survival and regional relapses, and relapse patterns with respect to the radiotherapy fields in esophageal cancer (EC). MATERIALS AND METHODS: The FDG-PET/CT image datasets of 56 patients were analyzed. All patients underwent definitive or neoadjuvant radio/chemotherapy (RCT). All patients suffering from persistent or recurrent local/regional-only disease after RCT were considered for salvage resection. Patients with adenocarcinoma without metastatic disease were considered for planned resection (usually within 3 months of treatment). RESULTS: Patients with PET-positive lymph nodes before treatment had a worse overall survival and a shorter disease-free survival than those without PET-positive nodes. They also had worse node and metastatic relapse-free survival. N2 patients had statistically significant poorer outcomes than N1-N0 patients and a better survival if the involved nodes were closer to the esophageal tumor. Involved node location by PET/CT also affected global, nodal and metastatic relapses. In addition, an increment of SUVmax value increased relative risk of death and increased relative risk of node and metastatic relapses. The first site of relapse was metastatic recurrence and, second, local recurrence. The most frequent were "in-field" loco/regional recurrence. We observed a relationship between patients classified-N1 and out-field nodal recurrence (p = 0.024), and between patients-N2 and in-field nodal recurrence. The number of PET-positive nodes was an independent significant prognostic predictor for relapse (p < 0.001). CONCLUSION: Our study shows that only FDG-PET/CT can provide prognostic information in EC. Nodal PET/CT uptake influences outcome and relapse location among EC patients.

Use of Smooth Muscle Myosin Heavy Chain as an Effective Marker of Follicular Dendritic Cells.

Smooth muscle myosin heavy chain (SMMHC) is a major structural component of the contractile apparatus in smooth muscle cells. Even though it is considered a relatively specific marker for terminal smooth muscle cell differentiation, expression in other cell types such as follicular dendritic cells (FDCs) has rarely been reported. To determine whether SMMHC represents an effective FDC marker in lymphoid tissues, we compared the immunohistochemical results for SMMHC with those of the traditional FDC markers podoplanin (D2-40) and CD21. Paraffin sections of 44 lymphoid tissues were analyzed, including 31 cases of follicular hyperplasia, 6 cases of follicular lymphoma, 2 cases of peripheral T-cell lymphoma, 3 cases of diffuse large B-cell lymphoma arising in follicular lymphoma, 1 case of nodular sclerosis classical Hodgkin lymphoma, and 1 case of small lymphocytic lymphoma. There was no statistically significant difference between the number of SMMHC-positive and D2-40-positive or CD21 lymph nodes (P>0.05). The extent and intensity of SMMHC-positive FDCs were similar to those of D2-40-positive FDCs (P=0.127 and 0.733, respectively), but significantly lower compared with those of CD21 cells (P=0.009 and 0.00002, respectively). However, in contrast to CD21 which was also positive in some germinal center B cells, SMMHC expression was restricted to FDCs. Our results indicate that SMMHC is an excellent marker for FDCs and can be particularly helpful in demonstrating the underlying architecture in lymphoid processes.

IFN-γ and IL-33 modulate mesenchymal stem cells function targeting Th1/Th17 axis in a murine skin transplantation model.

The immune regulatory properties of IL-33 have indicated that this cytokine has the capacity to target several immune cells under a variety of immunological responses, including overt inflammation and tolerance. Due to its versatile mechanistics, we sought to investigate the role of IL-33 on mesenchymal stem cells (MSC), a population of cells with recognizable modulatory functions. Our data indicates that IL-33 does not affect the expression of classical MSC markers such as CD29, CD44 and CD73, or the lack of CD45, CD11b and CD117. Also, we found that IL-33 greatly induces iNOS expression and stimulates the secretion of TGF-ß and IL-6. Next, we decided to test IFN-γ/IL-33-treated MSC using a skin transplantation model. Our data indicate that allogeneic skin-grafted animals treated with IFN-γ/IL-33-modulated MSC reject as controls. Complementing this finding, we observed that ex vivo re-stimulated draining lymph nodes (dLN) cells from these mice secrete lower amounts of IFN-γ and a slightly higher amount of IL-17. Beside a reduction in CD4+ and CD8+ T cells number, we preliminarily found an increment in the frequencies of CD4+Foxp3+IL-17+ T cells. Altogether, our data propose that IL-33 and IFN-γ modulate MSC phenotype and function, most likely targeting Th1/Th17 axis.