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Vaccination against communicable diseases is crucial for disease prevention, but this practice poses challenges to healthcare professionals in patients with haemophilia. Poor knowledge of the vaccination requirements for these patients and safety concerns often result in vaccination delay or avoidance. In order to address this issue, a panel of 11 Italian haemophilia and immunization experts conducted a Delphi consensus process to identify the main concerns regarding the safe use of vaccines in patients with haemophilia. The consensus was based on a literature search of the available evidence, which was used by the experts to design 27 consensus statements. A group of clinicians then rated these statements using the 5-point Likert-type scale (1 = strongly disagree; 5 = strongly agree). The main issues identified by the expert panel included vaccination schedule for haemophilic patients; protocol and optimal route of vaccine administration; vaccination of haemophilic patients with antibodies inhibiting coagulation factor VIII (inhibitors); and vaccination and risk of inhibitor development. This manuscript discusses these controversial areas in detail supported by the available literature evidence and provides evidence- and consensus-based recommendations. Overall, participants agreed on most statements, except those addressing the potential role of vaccination in inhibitor formation. Participants agreed that patients with haemophilia should receive vaccinations according to the institutional schedule for individuals without bleeding disorders; however, vaccination of patients with haemophilia requires comprehensive planning, taking into account disease severity, type and route of vaccination, and bleeding risk. Data also suggest vaccination timing does not need to take into consideration when the patient received factor VIII replacement.

Background: An increase in the frequency of circulating endothelial colony forming cells (ECFCs), the only subset of endothelial progenitor cells (EPCs) truly belonging to the endothelial phenotype, occurs in patients affected by primary myelofibrosis (PMF). Herein, they might contribute to the enhanced neovascularisation of fibrotic bone marrow and spleen. Store-operated Ca 2+ entry (SOCE) activated by the depletion of the inositol-1,4,5-trisphosphate (InsP3)-sensitive Ca2+ store drives proliferation in ECFCs isolated from both healthy donors (N-ECFCs) and subjects suffering from renal cellular carcinoma (RCC-ECFCs). SOCE is up-regulated in RCC-ECFCs due to the over-expression of its underlying molecular components, namely Stim1, Orai1, and TRPC1. Methodology/Principal Findings: We utilized Ca2+ imaging, real-time polymerase chain reaction, western blot analysis and functional assays to evaluate molecular structure and the functional role of SOCE in ECFCs derived from PMF patients (PMFECFCs). SOCE, induced by either pharmacological (i.e. cyclopiazonic acid or CPA) or physiological (i.e. ATP) stimulation, was significantly higher in PMF-ECFCs. ATP-induced SOCE was inhibited upon blockade of the phospholipase C/InsP3 signalling pathway with U73111 and 2-APB. The higher amplitude of SOCE was associated to the over-expression of the transcripts encoding for Stim2, Orai2-3, and TRPC1. Conversely, immunoblotting revealed that Stim2 levels remained constant as compared to N-ECFCs, while Stim1, Orai1, Orai3, TRPC1 and TRPC4 proteins were over-expressed in PMF-ECFCs. ATP-induced SOCE was inhibited by BTP-2 and low micromolar La3+ and Gd3+, while CPA-elicited SOCE was insensitive to Gd3+. Finally, BTP-2 and La 3+ weakly blocked PMF-ECFC proliferation, while Gd3+ was ineffective. Conclusions: Two distinct signalling pathways mediate SOCE in PMF-ECFCs; one is activated by passive store depletion and is Gd 3+-resistant, while the other one is regulated by the InsP 3-sensitive C

Endothelial progenitor cells (EPCs) have recently been employed in cell-based therapy (CBT) to promote regeneration of ischemic organs, such as heart and limbs. Furthermore, EPCs may sustain tumour vascularisation and provide an additional target for anticancer therapies. CBT is limited by the paucity of cells harvested from peripheral blood and suffers from several pitfalls, including the low rate of engrafted EPCs, whereas classic antiangiogenic treatments manifest a number of side effects and may induce resistance into the patients. CBT will benefit of a better understanding of the signal transduction pathway(s) which drive(s) EPC proliferation, trafficking, and incorporation into injured tissues. At the same time, this information might outline alternative molecular targets to impair tumor neovascularisation and improve the therapeutic outcome of antiangiogenic strategies. An increase in intracellular Ca2+ concentration is the key signal in the regulation of cellular replication, migration, and differentiation. In particular, Ca2+ signalling may regulate cellcycle progression, due to the Ca2+-sensitivity of a number of cycline-dependent kinases, and gene expression, owing to the Ca2+-dependence of several transcription factors. Recent work has outlined the role of the so-called store-operated Ca2+ entry in driving EPC proliferation and migration. Unravelling the mechanisms guiding EPC engraftment into neovessels might supply the biological bases required to improve CBT and anticancer treatments. For example, genetic manipulation of the Ca2+ signalling machinery could provide a novel approach to increase the extent of limb regeneration or preventing tumour vascularisation by EPCs.

Background: Juvenile myelomonocytic leukaemia (JMML) and chronic myelomonocytic leukaemia (CMML) are myelodysplastic myeloproliferative (MDS/MPN) neoplasms with unfavourable prognosis and without effective chemotherapy treatment. Trabectedin is a DNA minor groove binder acting as a modulator of transcription and interfering with DNA repair mechanisms; it causes selective depletion of cells of the myelomonocytic lineage. We hypothesised that trabectedin might have an antitumour effect on MDS/MPN. Methods: Malignant CD14+ monocytes and CD34+ haematopoietic progenitor cells were isolated from peripheral blood/bone marrow mononuclear cells. The inhibition of CFU-GM colonies and the apoptotic effect on CD14+ and CD34+ induced by trabectedin were evaluated. Trabectedin's effects were also investigated in vitro on THP-1, and in vitro and in vivo on MV-4-11 cell lines. Results: On CMML/JMML cells, obtained from 20 patients with CMML and 13 patients with JMML, trabectedin - at concentration pharmacologically reasonable, 1-5 nM - strongly induced apoptosis and inhibition of growth of haematopoietic progenitors (CFU-GM). In these leukaemic cells, trabectedin downregulated the expression of genes belonging to the Rho GTPases pathway (RAS superfamily) having a critical role in cell growth and cytoskeletal dynamics. Its selective activity on myelomonocytic malignant cells was confirmed also on in vitro THP-1 cell line and on in vitro and in vivo MV-4-11 cell line models. Conclusions: Trabectedin could be good candidate for clinical studies in JMML/CMML patients.

Background: Juvenile myelomonocytic leukaemia (JMML) and chronic myelomonocytic leukaemia (CMML) are myelodysplastic myeloproliferative (MDS/MPN) neoplasms with unfavourable prognosis and without effective chemotherapy treatment. Trabectedin is a DNA minor groove binder acting as a modulator of transcription and interfering with DNA repair mechanisms; it causes selective depletion of cells of the myelomonocytic lineage. We hypothesised that trabectedin might have an antitumour effect on MDS/MPN. Methods: Malignant CD14+ monocytes and CD34+ haematopoietic progenitor cells were isolated from peripheral blood/bone marrow mononuclear cells. The inhibition of CFU-GM colonies and the apoptotic effect on CD14+ and CD34+ induced by trabectedin were evaluated. Trabectedin's effects were also investigated in vitro on THP-1, and in vitro and in vivo on MV-4-11 cell lines. Results: On CMML/JMML cells, obtained from 20 patients with CMML and 13 patients with JMML, trabectedin - at concentration pharmacologically reasonable, 1-5 nM - strongly induced apoptosis and inhibition of growth of haematopoietic progenitors (CFU-GM). In these leukaemic cells, trabectedin downregulated the expression of genes belonging to the Rho GTPases pathway (RAS superfamily) having a critical role in cell growth and cytoskeletal dynamics. Its selective activity on myelomonocytic malignant cells was confirmed also on in vitro THP-1 cell line and on in vitro and in vivo MV-4-11 cell line models. Conclusions: Trabectedin could be good candidate for clinical studies in JMML/CMML patients.

Endothelial colony-forming cells (ECFCs) are the only endothelial progenitor cells (EPCs) that are capable of acquiring a mature endothelial phenotype. ECFCs are mainly mobilized from bone marrow to promote vascularization and represent a promising tool for cell-based therapy of severe ischemic diseases. Vascular endothelial growth factor (VEGF) stimulates the proliferation of peripheral blood-derived ECFCs (PB-ECFCs) through oscillations in intracellular Ca2+ concentration ([Ca2+]i). VEGF-induced Ca2+ spikes are driven by the interplay between inositol-1,4,5-trisphosphate (InsP3)-dependent Ca2+ release and store-operated Ca2+ entry (SOCE). The therapeutic potential of umbilical cord blood-derived ECFCs (UCB-ECFCs) has also been shown in recent studies. However, VEGF-induced proliferation of UCB-ECFCs is faster compared with their peripheral counterpart. Unlike PB-ECFCs, UCB-ECFCs express canonical transient receptor potential channel 3 (TRPC3) that mediates diacylglycerol-dependent Ca2+ entry. The present study aimed at investigating whether the higher proliferative potential of UCB-ECFCs was associated to any difference in the molecular underpinnings of their Ca 2+ response to VEGF. We found that VEGF induces oscillations in [Ca2+]i that are patterned by the interaction between InsP3-dependent Ca2+ release and SOCE. Unlike PB-ECFCs, VEGF-evoked Ca2+ oscillations do not arise in the absence of extracellular Ca2+ entry and after pharmacological (with Pyr3 and flufenamic acid) and genetic (by employing selective small interference RNA) suppression of TRPC3. VEGF-induced UCB-ECFC proliferation is abrogated on inhibition of the intracellular Ca2+ spikes. Therefore, the Ca 2+ response to VEGF in UCB-ECFCs is shaped by a different Ca 2+ machinery as compared with PB-ECFCs, and TRPC3 stands out as a promising target in EPC-based treatment of ischemic pathologies.

Background: Endothelial progenitor cells (EPCs) may be recruited from bone marrow to sustain tumor vascularisation and promote the metastatic switch. Understanding the molecular mechanisms driving EPC proliferation and tubulogenesis could outline novel targets for alternative anti-angiogenic treatments. Store-operated Ca2+ entry (SOCE), which is activated by a depletion of the intracellular Ca2+ pool, regulates the growth of human EPCs, where is mediated by the interaction between the endoplasmic reticulum Ca2+-sensor, Stim1, and the plasmalemmal Ca2+ channel, Orai1. As oncogenesis may be associated to the capability of tumor cells to grow independently on Ca2+ influx, it is important to assess whether SOCE regulates EPC-dependent angiogenesis also in tumor patients. Methodology/Principal Findings: The present study employed Ca2+ imaging, recombinant sub-membranal and mitochondrial aequorin, real-time polymerase chain reaction, gene silencing techniques and western blot analysis to investigate the expression and the role of SOCE in EPCs isolated from peripheral blood of patients affected by renal cellular carcinoma (RCC; RCC-EPCs) as compared to control EPCs (N-EPCs). SOCE, activated by either pharmacological (i.e. cyclopiazonic acid) or physiological (i.e. ATP) stimulation, was significantly higher in RCC-EPCs and was selectively sensitive to BTP-2, and to the trivalent cations, La3+ and Gd3+. Furthermore, 2-APB enhanced thapsigargin-evoked SOCE at low concentrations, whereas higher doses caused SOCE inhibition. Conversely, the anti-angiogenic drug, carboxyamidotriazole (CAI), blocked both SOCE and the intracellular Ca2+ release. SOCE was associated to the over-expression of Orai1, Stim1, and transient receptor potential channel 1 (TRPC1) at both mRNA and protein level The intracellular Ca2+ buffer, BAPTA, BTP-2, and CAI inhibited RCC-EPC proliferation and tubulogenesis. The genetic suppression of Stim1, Orai1, and TRPC1 blocked CPA-evoked SOCE in RCC-EPCs. Conclus

Hematopoietic progenitor and stem cells (HPSCs) have been employed in cell-based therapy (CBT) to promote neovascularisation and regeneration of ischemic organs, such as heart and limbs. Furthermore, endothelial progenitor cells (EPCs) may favour tumour growth and adverse vascular targeting treatment by incorporating into neovessels. CBT is hampered by the paucity of HPSCs harvested from peripheral blood and suffers from several pitfalls, including the differentiation outcome of transplanted cells and low percentage of engrafted cells. Therefore, CBT will benefit of a better understanding of the signal transduction pathway(s) which drive(s) HPSC homing, proliferation and incorporation into injured tissues. At the same time, this information might outline alternative molecular targets to combat tumoral neovascularisation. The elevation in intracellular Ca2+ concentration is the key signal in the regulation of cellular motility, replication, and differentiation. Intracellular Ca2+ waves regulate cytoskeleton re-organisation and disassembly at focal adhesions, thus stimulating migration and substrate adhesion, and induce DNA transcription by recruiting Ca2+-sensitive transcription factors. However, the Ca2+ signalling toolkit which underlies Ca2+ release from intracellular stores and Ca2+ entry across the plasmalemma in HPSCs is still unclear. Our recent work has shown that the so-called store-operated Ca2+ entry stimulates EPC growth. Unravelling the mechanisms guiding HPSC behaviour might supply the biological bases required to improve CBT. For instance, genetic manipulation of the Ca2+ signalling machinery (such as transfer of genes encoding for the Ca2+ channels involved in EPC proliferation) could provide a novel approach to increase the extent of limb neovascularisation and regeneration of damaged hearts.

Endothelial progenitor cells (EPCs) have recently been employed in cell-based therapy (CBT) to promote neovascularization and regeneration of ischemic organs, such as heart and limbs. Furthermore, EPCs may be recruited from bone marrow by growing tumors to drive the angiogenic switch through physical engrafting into the lumen of nascent vessels or paracrine release of pro-angiogenic factors. CBT is hampered by the paucity of EPCs harvested from peripheral blood and suffered from several pitfalls, including the differentiation outcome of transplanted cells and low percentage of engrafted cells. Therefore, CBT will benefit from a better understanding of the signal transduction pathway(s) which govern(s) EPC homing, proliferation and incorporation into injured tissues. At the same time, this information might outline alternative molecular targets to combat tumoral neovascularization. We have recently found that store-operated Ca2+ entry, a Ca2+-permeable membrane pathway that is activated upon depletion of the inositol-1,4,5-trisphosphate-sensitive Ca2+ pool, is recruited by vascular endothelial growth factor to support proliferation and tubulogenesis in human circulating endothelial colony forming cells (ECFCs). ECFCs are a subgroup of EPCs that circulate in the peripheral blood of adult individuals and are able to proliferate and differentiate into endothelial cells and form capillary networks in vitro and contribute to neovessel formation in vivo. The present review will discuss the relevance of SOCE to ECFC-based cell therapy and will address the pharmacological inhibition of store-dependent Ca2+ channels as a promising target for anti-angiogenic treatments.

Endothelial progenitor cells could be implicated in the aberrant neoangiogenesis that occurs in bone marrow and spleen in patients with primary myelofibrosis (PMF). However, antivascular endothelial growth factor (VEGF) monotherapy had only a modest and transient effect in these individuals. Recently it was found that VEGF-induced proangiogenic intracellular Ca2+ oscillations could be impaired in endothelial progenitor cells of subjects with malignancies. Therefore, we employed Ca2+ imaging, wavelet analysis, and functional assays to assess whether and how VEGF-induced Ca2+ oscillations are altered in PMF-derived endothelial progenitor cells. We focused on endothelial colony-forming cells (ECFCs), which are the only endothelial progenitor cell subtype capable of forming neovessels both in vivo and in vitro. VEGF triggers repetitive Ca2+ spikes in both normal ECFCs (N-ECFCs) and ECFCs obtained from PMF patients (PMF-ECFCs). However, the spiking response to VEGF is significantly weaker in PMF-ECFCs. VEGF-elicited Ca2+ oscillations are patterned by the interaction between inositol-1,4,5-trisphosphate-dependent Ca2+ mobilization and store-operated Ca2+ entry. However, in most PMF-ECFCs, Ca2+ oscillations are triggered by a store-independent Ca2+ entry pathway. We found that diacylglycerol gates transient receptor potential canonical 1 channel to trigger VEGF-dependent Ca2+ spikes by recruiting the phospholipase C/inositol-1,4,5-trisphosphate signaling pathway, reflected as a decrease in endoplasmic reticulum Ca2+ content. Finally, we found that, apart from being less robust and dysregulated as compared with N-ECFCs, VEGF-induced Ca2+ oscillations modestly stimulate PMF-ECFC growth and in vitro angiogenesis. These results may explain the modest effect of anti-VEGF therapies in PMF.

Bordetella holmesii, an emerging pathogen, can be misidentified as Bordetella pertussis by routine polymerase chain reaction (PCR). In some reports, up to 29% of the patients diagnosed with pertussis have in fact B. holmesii infection and invasive, non-respiratory B. holmesii infections have been reported worldwide. This misdiagnosis undermines the knowledge of pertussis' epidemiology, and may lead to misconceptions on pertussis vaccine's efficacy. Recently, the number of whooping cough cases has increased significantly in several countries. The aim of this retrospective study was to determine whether B. holmesii was contributing to the increase in laboratory-confirmed cases of B. pertussis in Switzerland. A multiplex species-specific quantitative PCR assay was performed on 196 nasopharyngeal samples from Swiss patients with PCR-confirmed Bordetella infection (median age: 6 years-old, minimum 21 days-old, maximum 86 years-old), formerly diagnosed as Bordetella pertussis (IS481+). No B. holmesii (IS481+, IS1001-, hIS1001+) was identified. We discuss whether laboratories should implement specific PCR to recognize different Bordetella species. We conclude that in Switzerland B. holmesii seems to be circulating less than in neighboring countries and that specific diagnostic procedures are not necessary routinely. However, as the epidemiological situation may change rapidly, periodic reevaluation is suggested.