Src Kinases Are Required for a Balanced Production of IL-12/IL-23 in Human Dendritic Cells Activated by Toll-Like Receptor Agonists

BACKGROUND: Pathogen recognition by dendritic cells (DC) is crucial for the initiation of both innate and adaptive immune responses. Activation of Toll-like Receptors (TLRs) by microbial molecular patterns leads to the maturation of DC, which present the antigen and activate T cells in secondary lymphoid tissues. Cytokine production by DC is critical for shaping the adaptive immune response by regulating T helper cell differentiation. It was previously shown by our group that Src kinases play a key role in cytokines production during TLR4 activation in human DC. PRINCIPAL FINDINGS: In this work we investigated the role of Src kinases during different TLRs triggering in human monocyte-derived DC (MoDC). We found that Src family kinases are important for a balanced production of inflammatory cytokines by human MoDC upon stimulation of TLR3 and 8 with their respective agonists. Disruption of this equilibrium through pharmacological inhibition of Src kinases alters the DC maturation pattern. In particular, while expression of IL-12 and other inflammatory cytokines depend on Src kinases, the induction of IL-23 and co-stimulatory molecules do not. Accordingly, DC treated with Src inhibitors are not compromised in their ability to induce CD4 T cell proliferation and to promote the Th17 subset survival but are less efficient in inducing Th1 differentiation. CONCLUSIONS: We suggest that the pharmacological modulation of DC maturation has the potential to shape the quality of the adaptive immune response and could be exploited for the treatment of inflammation-related diseases

Role of the Hedgehog Pathway and CAXII in Controlling Melanoma Cell Migration and Invasion in Hypoxia

Simple Summary Malignant melanoma is the leading cause of death among skin cancer patients due to its tendency to metastasize. Hypoxia, which is a common feature of the tumor microenvironment, as well as different alterations at the molecular level, may affect melanoma aggressiveness. The aims and the objectives of this work were to investigate whether and how the Hedgehog pathway and CAXII may control malignant melanoma cell migration and invasiveness either in normoxic or hypoxic conditions. To this end we evaluated the migratory and invasive capabilities of SK-MEL-28 and A375 cell lines, where the hedgehog pathways and CAXII were inhibited by short interfering RNA. Our results indicate that SMO and GLI1 silencing caused the downregulation of CAXII expression. Furthermore, the Hedgehog pathway and CAXII inhibition, resulted in impaired melanoma cell migration and invasion either under normoxic or hypoxic conditions. The fact that CAXII and the Hedgehog pathway are relevant in melanoma cell invasion may be exploited to discover novel and promising therapeutical targets for melanoma clinical management. Background: Malignant melanoma is the leading cause of death among skin cancer patients due to its tendency to metastasize. Alterations at the molecular level are often evident, which is why melanoma biology has garnered increasing interest. The hedgehog (Hh) pathway, which is essential for embryonic development, is aberrantly re-activated in melanoma and may represent a promising therapeutic target. In addition, carbonic anhydrase XII (CAXII) represents a poor prognostic target for hypoxic tumors, such as melanoma, and is involved in cell migration. Thus, we decided to investigate whether and how the Hh pathway and CAXII may control melanoma cell migration and invasiveness. Methods: The migratory and invasive capabilities of SK-MEL-28 and A375 cell lines, either un-transfected or transiently transfected with Smoothened (SMO), GLI1, or CAXII siRNA, were studied under normoxic or hypoxic conditions. Results: For the first time, we showed that SMO and GLI1 silencing resulted in the downregulation of CAXII expression in both moderately and highly invasive melanoma cells under hypoxia. The Hh pathway as well as CAXII inhibition by siRNA resulted in impaired malignant melanoma migration and invasion. Conclusion: Our results suggest that CAXII and the Hh pathway are relevant in melanoma invasion and may be novel and promising therapeutical targets for melanoma clinical management

The acquired immune response to the mucosal adjuvant LTK63 imprints the mouse lung with a protective signature

Abstract LTK63, a nontoxic mutant of Escherichia coli heat labile enterotoxin (LT), is a potent and safe mucosal adjuvant that has also been shown to confer generic protection to several respiratory pathogens. To understand the mechanisms of action underlying the LTK63 protective effect, we analyzed the molecular and cellular events triggered by its administration in vivo. We show here that LTK63 intrapulmonary administration induced in the mouse lung a specific gene expression signature characterized by the up-regulation of cell cycle genes, several host defense genes, chemokines, chemokine receptors, and immune cell-associated genes. Such a transcriptional profile reflected the activation of alveolar macrophages and the recruitment to the lung of T and B cells and innate immune cells such as granulocytes, NK, and dendritic cells. All of these events were T cell dependent and specific for LTK63 because they were absent in SCID and nude mice. Additionally, we showed that LTK63 induces a potent adaptive immune response against itself directed to the lung. We propose that acquired response to LTK63 is the driving force for the local recruitment of both adaptive and innate immune cells. Our data suggest that LTK63 acts as an airway infection mimic that establishes a generic protective environment limiting respiratory infection by innate immune mechanisms and by improving adaptive responses to invading pathogens.</jats:p

Total lung sparing surgery for tracheobronchial low-grade malignancies

BACKGROUND: Total-lung sparing tracheo-bronchial sleeve resections are a step forward in the treatment of low-grade bronchial tumors where minimal resection margins are required to achieve the complete control of the disease.METHODS: We retrospectively collected the data of patients who underwent total-lung sparing procedures for low-grade trachea-bronchial tumors at two thoracic surgery centres from January 1984 until October 2019.RESULTS: We selected 98-patients, 46-females(47%) and 52-males(53%) with a median age of 39years(range7-70). Thirty-four patients underwent an operative endoscopy before surgery(32-laser-treatment,2-endobronchial-stenting). The surgical resection were 9(9%)-tracheal carina, 18(18%)-second carina, 31(32%)-left main bronchi, 25(26%)-right main bronchi and 15(15%)-intermediate-bronchus. The median length of the resected bronchus was 2.2cm. Median post-operative in-hospital stay was 8-days, no perioperative mortality was observed. Postoperative complications were recorded in 26-patients(27%). The final histology was 37-typical carcinoids(38%), 10-atypical carcinoids(10%), 29-adenoid cystic carcinomas(30%), 15-mucoepidermoid carcinomas(15%), 6-inflammatory myofibroblastic tumors(6%) and 1-glomic tumor(1%). Twenty-two patients had positive resection margins and received adjuvant radiotherapy. Three patients with adenoid cystic carcinoma had recurrence(1-local,2-systemic). After a median follow-up time of 54.5months(range4-360), the overall actuarial 5-year survival was 97%.CONCLUSIONS: Total-lung sparing tracheo-bronchial sleeve resection for low-grade malignancy require high surgical skills but the hospital morbidity and mortality are very low. This Technique is adequate and safe for highly selected patients with low-grade endobronchial malignancies and it's use should be encouraged in experienced centres