Autoimmune Diseases and Plasma Cells Dyscrasias: Pathogenetic, Molecular and Prognostic Correlations.

Multiple myeloma and monoclonal gammopathy of undetermined significance are plasma cell dyscrasias characterized by monoclonal proliferation of pathological plasma cells with uncontrolled production of immunoglobulins. Autoimmune pathologies are conditions in which T and B lymphocytes develop a tendency to activate towards self-antigens in the absence of exogenous triggers. The aim of our review is to show the possible correlations between the two pathological aspects. Molecular studies have shown how different cytokines that either cause inflammation or control the immune system play a part in the growth of immunotolerance conditions that make it easier for the development of neoplastic malignancies. Uncontrolled immune activation resulting in chronic inflammation is also known to be at the basis of the evolution toward neoplastic pathologies, as well as multiple myeloma. Another point is the impact that myeloma-specific therapies have on the course of concomitant autoimmune diseases. Indeed, cases have been observed of patients suffering from multiple myeloma treated with daratumumab and bortezomib who also benefited from their autoimmune condition or patients under treatment with immunomodulators in which there has been an arising or worsening of autoimmunity conditions. The role of bone marrow transplantation in the course of concomitant autoimmune diseases remains under analysis.

Proactive Risk Assessment through Failure Mode and Effect Analysis (FMEA) for Perioperative Management Model of Oral Anticoagulant Therapy: A Pilot Project.

INTRODUCTION: Correct perioperative management of anticoagulant therapy is essential to prevent thromboembolic events and reduce the risk of bleeding. The lack of universally accepted guidelines makes perioperative anticoagulant therapy management difficult. The present study aims to identify the perioperative risks of oral anticoagulant therapy and to reduce adverse events through Failure Mode and Effect Analysis (FMEA). MATERIALS AND METHODS: A multidisciplinary working group was set up, and four main phases of the process were identified. Each of these phases was divided into micro-activities to identify the related possible failure modes and their potential consequences. The Risk Priority Number was calculated for each failure mode. RESULTS AND DISCUSSION: Seventeen failure modes were identified in the entire perioperative period; those with a higher priority of intervention concern the incorrect timing between therapy suspension and surgery, and the incorrect assessment of the bleeding risk related to the invasive procedure. CONCLUSION: The FMEA method can help identify anticoagulant therapy perioperative failures and implement the management and patient safety of surgical procedures.

Bordetella pertussis commits human dendritic cells to promote a Th1/Th17 response through the activity of adenylate cyclase toxin and MAPK-pathways.

The complex pathology of B. pertussis infection is due to multiple virulence factors having disparate effects on different cell types. We focused our investigation on the ability of B. pertussis to modulate host immunity, in particular on the role played by adenylate cyclase toxin (CyaA), an important virulence factor of B. pertussis. As a tool, we used human monocyte derived dendritic cells (MDDC), an ex vivo model useful for the evaluation of the regulatory potential of DC on T cell immune responses. The work compared MDDC functions after encounter with wild-type B. pertussis (BpWT) or a mutant lacking CyaA (BpCyaA-), or the BpCyaA- strain supplemented with either the fully functional CyaA or a derivative, CyaA*, lacking adenylate cyclase activity. As a first step, MDDC maturation, cytokine production, and modulation of T helper cell polarization were evaluated. As a second step, engagement of Toll-like receptors (TLR) 2 and TLR4 by B. pertussis and the signaling events connected to this were analyzed. These approaches allowed us to demonstrate that CyaA expressed by B. pertussis strongly interferes with DC functions, by reducing the expression of phenotypic markers and immunomodulatory cytokines, and blocking IL-12p70 production. B. pertussis-treated MDDC promoted a mixed Th1/Th17 polarization, and the activity of CyaA altered the Th1/Th17 balance, enhancing Th17 and limiting Th1 expansion. We also demonstrated that Th1 effectors are induced by B. pertussis-MDDC in the absence of IL-12p70 through an ERK1/2 dependent mechanism, and that p38 MAPK is essential for MDDC-driven Th17 expansion. The data suggest that CyaA mediates an escape strategy for the bacterium, since it reduces Th1 immunity and increases Th17 responses thought to be responsible, when the response is exacerbated, for enhanced lung inflammation and injury.

Genetically detoxified pertussis toxin induces Th1/Th17 immune response through MAPKs and IL-10-dependent mechanisms.

Genetically detoxified pertussis toxin (dPT) maintains the protein structure and the immunological properties, but not the enzymatic activity. In search of an adjuvant able to direct polarization of T cells to induce/potentiate protective immune response to a variety of infectious disease, we investigated the role played by dPT on human dendritic cell-driven Th polarization and analyzed the intracellular signaling events. To reach these aims, we used a highly purified dPT preparation devoid of contamination and monocyte-derived dendritic cells, a well-characterized model to study ex vivo the polarization of the immune responses. First, we analyzed dPT-induced monocyte-derived dendritic cell maturation, longevity, and cytokine production and, in a second step, we analyzed TLR4/2 engagement by dPT, the connected signaling events, and their relevance to the skewing of Th cell polarization. These approaches allowed us to clarify some of the mechanisms that are responsible for dPT-driven regulation of T cell polarization. We demonstrated that dPT acts utilizing TLR4/TLR2 engagement, being the signaling induced by the former stronger. dPT, through a crucial role played by MAPK and IL-10, favors the expansion of the Th1/Th17 immunity. Indirect evidences indicated that dPT-induced Th17 expansion is counterregulated by the PI3K pathway. For its properties and being already used in humans as vaccine Ag in pertussis, dPT may represents a valid candidate adjuvant to foster immune protective response in vaccines against infectious diseases where Th1/Th17 are mediating host immunity.

Lipopolysaccharides from Bordetella pertussis and Bordetella parapertussis differently modulate human dendritic cell functions resulting in divergent prevalence of Th17-polarized responses.

Bordetella pertussis and B. parapertussis are the etiological agents of pertussis, yet the former has a higher incidence and is the cause of a more severe disease, in part due to pertussis toxin. To identify other factors contributing to the different pathogenicity of the two species, we analyzed the capacity of structurally different lipooligosaccharide (LOS) from B. pertussis and LPS from B. parapertussis to influence immune functions regulated by dendritic cells. Either B. pertussis LOS and B. parapertussis LPS triggered TLR4 signaling and induced phenotypic maturation and IL-10, IL-12p40, IL-23, IL-6, and IL-1beta production in human monocyte-derived dendritic cells (MDDC). B. parapertussis LPS was a stronger inducer of all these activities as compared with B. pertussis LOS, with the notable exception of IL-1beta, which was equally produced. Only B. parapertussis LPS was able to induce IL-27 expression. In addition, although MDDC activation induced by B. parapertussis LPS was greatly dependent on soluble CD14, B. pertussis LOS activity was CD14-independent. The analysis of the intracellular pathways showed that B. parapertussis LPS and B. pertussis LOS equally induced IkappaBalpha and p38 MAPK phosphorylation, but B. pertussis LOS triggered ERK1/2 phosphorylation more rapidly and at higher levels than B. parapertussis LPS. Furthermore, B. pertussis LOS was unable to induce MyD88-independent gene induction, which was instead activated by B. parapertussis LPS, witnessed by STAT1 phosphorylation and induction of the IFN-dependent genes, IFN regulatory factor-1 and IFN-inducible protein-10. These differences resulted in a divergent regulation of Th cell responses, B. pertussis LOS MDDC driving a predominant Th17 polarization. Overall, the data observed reflect the different structure of the two LPS and the higher Th17 response induced by B. pertussis LOS may contribute to the severity of pertussis in humans.

IFN-gamma arms human dendritic cells to perform multiple effector functions.

Dendritic cells (DCs) are central players in immunity and are used in immune-adoptive vaccine protocols in humans. IFN-gamma, mandatory in Th-1 polarization and endowed with regulatory properties, is currently used to condition monocyte-derived DCs (MDDC) in cancer therapy and in clinical trials to treat chronic infectious diseases. We therefore performed a wide analysis of IFN-gamma signaling consequences on MDDC multiple effector functions. IFN-gamma itself induced IL-27p28 expression and survival but did not promote relevant CCR7-driven migration or activated Th-1 cell recruitment capacity in MDDC. Administered in association with classical maturation stimuli such as CD40 or TLR-4 stimulation, IFN-gamma up-regulated IL-27 and IL-12 production, CCR7-driven migration, and activated Th-1 cell recruitment, whereas it decreased IL-10 production and STAT3 phosphorylation. CD38 signaling, which orchestrates migration, survival, and Th-1 polarizing ability of mature MDDC, was involved in IFN-gamma-mediated effects. Thus, IFN-gamma is a modulator of multiple DC effector functions that can be helpful in MDDC-based vaccination protocols. These data also help understand the dual role exerted by this cytokine as both an inducer and a regulator of inflammation and immune response.

Lipooligosaccharide from Bordetella pertussis induces mature human monocyte-derived dendritic cells and drives a Th2 biased response.

Bordetella pertussis has a distinctive cell wall lipooligosaccharide (LOS) that is released from the bacterium during bacterial division and killing. LOS directly participates in host-bacterial interactions, in particular influencing the dendritic cells' (DC) immune regulatory ability. We analyze LOS mediated toll-like receptor (TLR) activation and dissect the role played by LOS on human monocyte-derived (MD)DC functions and polarization of the host T cell response. LOS activates TLR4-dependent signaling and induces mature MDDC able to secrete IL-10. LOS-matured MDDC enhance allogeneic presentation and skew T helper (Th) cell polarization towards a Th2 phenotype. LOS protects MDDC from undergoing apoptosis, prolonging their longevity and their functions. Compared to Escherichia coli lipopolysaccharide (LPS), the classical DC maturation stimulus, LOS was a less efficient inducer of TLR4 signaling, MDDC maturation, IL-10 secretion and allogeneic T cell proliferation and it was not able to induce IL-12p70 production in MDDC. However, the MDDC apoptosis protection exerted by LOS and LPS were comparable. In conclusion, LOS treated MDDC are able to perform antigen presentation in a context that promotes licensing of Th2 effectors. Considering these properties, the use of LOS in the formulation of acellular pertussis vaccines to potentiate protective and adjuvant capacity should be taken into consideration.

Surface layer proteins from Clostridium difficile induce inflammatory and regulatory cytokines in human monocytes and dendritic cells.

Clostridium difficile, an etiological agent of most cases of antibiotic-associated diarrhea, exerts its pathological action mainly by the activity of toxin A and toxin B. Less known is the role that S-layer proteins (SLPs), predominant surface components of the bacterium, may play in pathogenesis. Here, we evaluate the ability of SLPs to modulate the function of human monocytes and dendritic cells (DC) and to induce inflammatory and regulatory cytokines, influencing the natural and adaptive immune response. To this aim, SLPs were extracted from the clinical isolate C253 and characterized for their effects on immune cells. SLPs induced the release of elevated amounts of interleukin (IL)-1beta and IL-6 pro-inflammatory cytokines by resting monocytes, induced maturation of human monocyte-derived DC (MDDC), and enhanced proliferation of allogeneic T cells. C253-SLP-treated MDDC also secreted large amounts of IL-10 and IL-12p70 and induced a mixed Th1/Th2 orientation of immune response in naïve CD4 T cells. In conclusion, C. difficile SLPs may contribute to the pathogenicity of the bacterium by perturbing the fine balance of inflammatory and regulatory cytokines. These data are of interest also in the light of the possible use of SLPs in a multicomponent vaccine against C. difficile infections for high-risk patients.

Bordetella pertussis inhibition of interleukin-12 (IL-12) p70 in human monocyte-derived dendritic cells blocks IL-12 p35 through adenylate cyclase toxin-dependent cyclic AMP induction.

Bordetella pertussis, the causative agent of whooping cough, possesses an array of virulence factors, including adenylate cyclase toxin (ACT), relevant in the establishment of infection. Here we better define the impact of cyclic AMP (cAMP) intoxication due to the action of ACT on dendritic cell (DC)-driven immune response, by infecting monocyte-derived DC (MDDC) with an ACT-deficient B. pertussis mutant (ACT- 18HS19) or its parental strain (WT18323). Both strains induced MDDC maturation and antigen-presenting cell functions; however, only ACT- 18HS19 infected MDDC-induced production of interleukin-12 (IL-12) p70. Gene expression analysis of the IL-12 cytokine family subunits revealed that both strains induced high levels of p40 (protein chain communal to IL-12 p70 and IL-23) as well as p19, a subunit of IL-23. Conversely only ACT- 18HS19 infection induced consistent transcription of IL-12 p35, a subunit of IL-12 p70. Addition of the cAMP analogous D-butyril-cAMP (D-cAMP) abolished IL-12 p70 production and IL-12 p35 expression in ACT- 18HS19-infected MDDC. ACT- 18HS19 infection induced the expression of the transcription factors interferon regulatory factor 1 (IRF-1) and IRF-8 and of beta interferon, involved in IL-12 p35 regulation, and the expression of these genes was inhibited by D-cAMP addition and in WT18323-infected MDDC. The concomitant expression of IL-12 p70 and IL-23 allowed ACT- 18HS19 to trigger a more pronounced T helper 1 polarization compared to WT18323. The present study suggests that ACT-dependent cAMP induction leads to the inhibition of pathways ultimately leading to IL-12 p35 production, thus representing a mechanism for B. pertussis to escape the host immune response.