Recommendations for the Clinician Role in Reducing Gun Violence.

There is a growing need for clear and definitive guidelines to prevent firearm violence in communities across the United States. Recommendations explore the utility and feasibility of universal screenings and recommend utilizing universal screening due to a lack of a clear risk to it. Providers should also work to create risk reduction plans with patients as well. Furthermore, recommendations for mental health care, counseling, and bystander training are made for institutions and their providers.

Characteristics associated with poor atrial fibrillation-related quality of life in adults with atrial fibrillation.

PURPOSE: Few studies have examined the relationship between poor atrial fibrillation-related quality of life (AFQoL) and a battery of geriatric factors. The objective of this study is to describe factors associated with poor AFQoL in older adults with atrial fibrillation (AF) with a focus on sociodemographic and clinical factors and a battery of geriatric factors. METHODS: Cross-sectional analysis of a prospective cohort study of participants aged 65+ with high stroke risk and AF. AFQoL was measured using the validated Atrial Fibrillation Effect on Quality of Life (score 0-100) and categorized as poor (<80) or good (80-100). Chi-square and t -tests evaluated differences in factors across poor AFQoL and significant characteristics ( P  < 0.05) were entered into a logistic regression model to identify variables related to poor AFQoL. RESULTS: Of 1244 participants (mean age 75.5), 42% reported poor AFQoL. Falls in the past 6 months, pre/frail and frailty, depression, anxiety, social isolation, vision impairment, oral anticoagulant therapy, rhythm control, chronic obstructive pulmonary disease and polypharmacy were associated with higher odds of poor AFQoL. Marriage and college education were associated with a lower odds of poor AFQoL. CONCLUSIONS: More than 4 out of 10 older adults with AF reported poor AFQoL. Geriatric factors associated with higher odds of reporting poor AFQoL include recent falls, frailty, depression, anxiety, social isolation and vision impairment. Findings from this study may help clinicians screen for patients with poor AFQoL who could benefit from tailored management to ensure the delivery of patient-centered care and improved well being among older adults with AF.

Medication cost-reducing behaviors in older adults with atrial fibrillation: The SAGE-AF study.

BACKGROUND: As patient prices for many medications have risen steeply in the United States, patients may engage in cost-reducing behaviors (CRBs) such as asking for generic medications or purchasing medication from the Internet. OBJECTIVE: The objective of this study is to describe patterns of CRB, cost-related medication nonadherence, and spending less on basic needs to afford medications among older adults with atrial fibrillation (AF) and examine participant characteristics associated with CRB. METHODS: Data were from a prospective cohort study of older adults at least 65 years with AF and a high stroke risk (CHA2DS2VASc ≥ 2). CRB, cost-related medication nonadherence, and spending less on basic needs to afford medications were evaluated using validated measures. Chi-square and t tests were used to evaluate differences in characteristics across CRB, and statistically significant characteristics (P < 0.05) were entered into a multivariable logistic regression to examine factors associated with CRB. RESULTS: Among participants (N = 1224; mean age 76 years; 49% female), 69% reported engaging in CRB, 4% reported cost-related medication nonadherence, and 6% reported spending less on basic needs. Participants who were cognitively impaired (adjusted odds ratio 0.69 [95% CI 0.52-0.91]) and those who did not identify as non-Hispanic white (0.66 [0.46-0.95]) were less likely to engage in CRB. Participants who were married (1.88 [1.30-2.72]), had a household income of $20,000-$49,999 (1.52 [1.02-2.27]), had Medicare insurance (1.38 [1.04-1.83]), and had 4-6 comorbidities (1.43 [1.01-2.01]) had significantly higher odds of engaging in CRB. CONCLUSION: Although CRBs were common among older adults with AF, few reported cost-related medication nonadherence and spending less on basic needs. Patients with cognitive impairment may benefit from pharmacist intervention to provide support in CRB and patient assistance programs.

Work and the future as represented by French adolescents: the role of secondary school type and anticipated duration of post-secondary education.

This study, conducted in France, sought to describe the organization of the content of the social representations that high school students in transition construct of work and their own future, taking into account two variables: their type of secondary school and the anticipated length of their post-secondary education. For this purpose, 669 adolescents enrolled at three types of secondary schools (middle school, general high school, and vocational high school) were given two free-association tasks (with the inducers "work" and "your future"). Prototypical analyses for each of the variables considered were carried out on the corpus of words collected. The results highlight the place occupied by money and post-secondary education in the set of representations and the advantage of taking into account the subjective variable "anticipated length of post-secondary education" to better understand the role that contemporary uncertainties play. Thus, students who do not plan to pursue higher studies seem more worried about their future than others. On the theoretical level, the article notably highlights the benefit of integrating certain concepts developed in social psychology along with studies developed in the field of career guidance. In terms of practice, finally, it argues for a better integration of anticipations in the support aimed at helping students plan their transitions.

Le travail et l'avenir tels que représentés par les adolescents français : Le rôle du type d'école secondaire et de la durée anticipée des études postsecondaires Cette étude, menée en France, visait à décrire l'organisation du contenu des représentations sociales que les lycéen·ne·s en transition construisent du travail et de leur propre avenir, en tenant compte de deux variables : leur type d'établissement secondaire et la durée anticipée de leurs études postsecondaires. Pour ce faire, 669 adolescent·e·s inscrits dans trois types d'établissements secondaires (collège, lycée général et lycée professionnel) ont été soumis à deux tâches d'association libre (avec les inducteurs "travail" et "votre avenir"). Des analyses prototypiques pour chacune des variables considérées ont été réalisées sur le corpus de mots recueillis. Les résultats mettent en évidence la place occupée par l'argent et les études postsecondaires dans l'ensemble des représentations et l'intérêt de prendre en compte la variable subjective "durée anticipée des études postsecondaires" pour mieux comprendre le rôle que jouent les incertitudes contemporaines. Ainsi, les étudiant·e·s qui n'envisagent pas de poursuivre des études supérieures semblent plus inquiets de leur avenir que les autres. Sur le plan théorique, l'article souligne notamment l'intérêt d'intégrer certains concepts développés en psychologie sociale aux études développées dans le domaine de l'orientation professionnelle. Sur le plan pratique, enfin, il plaide pour une meilleure intégration des anticipations dans l'accompagnement visant à aider les étudiant·e·s à planifier leurs transitions.

El trabajo y el futuro según los adolescentes franceses: el papel del tipo de escuela secundaria y la duración prevista de los estudios postsecundarios Este estudio, realizado en Francia, pretendía describir la organización del contenido de las representaciones sociales que los estudiantes de secundaria en transición construyen sobre el trabajo y su propio futuro, teniendo en cuenta dos variables: su tipo de escuela secundaria y la duración prevista de su educación postsecundaria. Para ello, 669 adolescentes matriculados en tres tipos de centros de enseñanza secundaria (secundaria, bachillerato general y bachillerato profesional) recibieron dos tareas de asociación libre (con los inductores "trabajo" y "tu futuro"). Sobre el corpus de palabras recogidas se realizaron análisis prototípicos para cada una de las variables consideradas. Los resultados ponen de manifiesto el lugar que ocupan el dinero y los estudios postsecundarios en el conjunto de representaciones y la ventaja de tener en cuenta la variable subjetiva "duración prevista de los estudios postsecundarios" para comprender mejor el papel que desempeñan las incertidumbres contemporáneas. Así, los estudiantes que no tienen previsto cursar estudios superiores parecen estar más preocupados por su futuro que los demás. En el plano teórico, el artículo destaca especialmente el beneficio de integrar ciertos conceptos desarrollados en psicología social junto con los estudios desarrollados en el campo de la orientación profesional. En el plano práctico, por último, aboga por una mejor integración de las anticipaciones en el apoyo destinado a ayudar a los estudiantes a planificar sus transiciones.

Multicenter evaluation of the IL-3-pSTAT5 assay to assess the potency of cryopreserved stem cells from cord blood units: The BEST Collaborative study.

BACKGROUND: The IL-3-pSTAT5 assay, a new, rapid, and standardized flow-cytometry-based assay may compensate for several limitations of the colony-forming unit (CFU) assay typically used for stem cell potency assessments of cord blood units (CBU). We performed an inter-laboratory evaluation of the performance of this new assay. STUDY DESIGN AND METHODS: This Biomedical Excellence for Safer Transfusion (BEST) Collaborative multicenter, international study included 15 participants from public cord blood banks (CBBs), CBB-supporting research laboratories, and stem cell laboratories. To perform the IL-3-pSTAT5 assay, participating centers received reagents, instructions, and 10 blind CBU samples, including eight normal samples and two samples exposed to a transient warming event. We measured inter-laboratory agreement qualitatively (proportion of correctly classified samples) and quantitatively (coefficient of variation [CV], correlation coefficients, receiver operating characteristics (ROC) curve, and intraclass correlation coefficient [ICC]). RESULTS: The qualitative agreement was 97.3% (i.e., 107/110; Fleiss' kappa = 0.835). The average CV on a per-sample basis was 11.57% among all samples, 8.99% among normal samples, and on a per-center basis was 9.42% among normal samples. In a correlation matrix that compared results across centers, the mean Pearson's correlation coefficient was 0.88 (standard deviation = 0.04). The ICC was 0.83 (95% confidence interval = 0.68-0.95). The area under the curve (AUC) from the ROC curve was 0.9974. DISCUSSION: Excellent qualitative and quantitative agreement was exhibited across laboratories. The IL-3-pSTAT5 assay may therefore be implemented in flow cytometry laboratories to rapidly and reliably provide standardized measures of stem cell potency in CBUs.

Intensive monitoring of minimal residual disease and chimerism after allogeneic hematopoietic stem cell transplantation for acute leukemia in children.

Posttransplant leukemia detection before overt relapse is key to the success of immunotherapeutic interventions, as they are more efficient when leukemia burden is low. However, optimal schedule and monitoring methods are not well defined. We report the intensive bone marrow monitoring of minimal residual disease (MRD) using flow cytometry (FC) and nested reverse transcription polymerase chain reaction (RT-PCR) whenever a fusion transcript allowed it and chimerism by PCR at 11 timepoints in the first 2 years after transplant. Seventy-one transplants were performed in 59 consecutive children, for acute myeloid (n = 38), lymphoid (n = 31), or mixed-phenotype (n = 2) leukemia. MRD was monitored in 62 cases using FC (n = 58) and/or RT-PCR (n = 35). Sixty-seven percent of leukemia recurrences were detected before overt relapse, with a detection rate of 89% by RT-PCR and 40% by FC alone. Increased mixed chimerism was never the first evidence of recurrence. Two patients monitored by RT-PCR relapsed without previous MRD detection, one after missed scheduled evaluation and the other 4.7 years post transplant. Among the 22 cases with MRD detection without overt relapse, 19 received therapeutic interventions. Eight (42%) never relapsed. In conclusion, intensive marrow monitoring by RT-PCR effectively allows for early detection of posttransplant leukemia recurrence.

A cross-sectional analysis of racial differences in accelerated aging and cognitive function among patients with atrial fibrillation: The SAGE-AF study: Forrester, Accelerated aging and cognitive function.

BACKGROUND: Non-Whites are more likely to suffer from cognitive impairment and complications of atrial fibrillation (AF) than Whites, though Whites are more likely to be diagnosed with AF. We examined whether non-Whites with AF are biologically older than Whites with AF and whether accelerated biological aging is associated with cognitive functioning. METHODS: We used baseline data from the ongoing Systematic Assessment of Geriatric Elements in Atrial Fibrillation prospective cohort study, collected 2016-2020 across ambulatory care practices in Massachusetts and Georgia. Of 1244 enrolled, 974 participants with full biological data were included in the present analysis. Accelerated aging (AccA) was calculated based on a combination of biomarkers associated with age and physiological "wear and tear." FINDINGS: The main outcome was score on Montreal Cognitive Assessment (MoCA). Non-Whites had 2.9 years more AccA than Whites and higher AccA was associated with a lower MoCA score among both Whites (-0.06, 95% CI: -0.10, -0.03) and non-Whites (-0.14, 95% CI: -0.27, 0.02). This association was significantly greater among non-whites (-0.11, 95% CI: -0.20, -0.01). INTERPRETATION: Non-White AF patients are functionally "older" than their White counterparts and experience a stronger deleterious association between AccA and cognition. These findings underscore the importance of taking functional age into account when treating patients with AF, particularly non-White patients, to enhance treatment and improve AF outcomes.

Differences in Perceived and Predicted Bleeding Risk in Older Adults With Atrial Fibrillation: The SAGE-AF Study.

Background Little research has evaluated patient bleeding risk perceptions in comparison with calculated bleeding risk among oral anticoagulant users with atrial fibrillation. Our objective was to investigate underestimation of bleeding risk and to describe the characteristics and patient-reported outcomes associated with underestimation of bleeding risk. Methods and Results In the SAGE-AF (Systematic Assessment of Geriatric Elements in Atrial Fibrillation) study, a prospective cohort study of patients ≥65 years with atrial fibrillation, a CHA2DS2-VASc risk score ≥2 and who were on oral anticoagulant therapy, we compared patients' self-reported bleeding risk with their predicted bleeding risk from their HAS-BLED score. Among the 754 participants (mean age 74.8 years, 48.3% women), 68.0% underestimated their bleeding risk. Participants who were Asian or Pacific Islander, Black, Native American or Alaskan Native, Mixed Race or Hispanic (non-White) (adjusted OR [AOR], 0.45; 95% CI, 0.24-0.82) and women (AOR, 0.62; 95% CI, 0.40-0.95) had significantly lower odds of underestimating their bleeding risk than respective comparison groups. Participants with a history of bleeding (AOR, 3.07; 95% CI, 1.73-5.44) and prior hypertension (AOR, 4.33; 95% CI, 2.43-7.72), stroke (AOR, 5.18; 95% CI, 1.87-14.40), or renal disease (AOR, 5.05; 95% CI, 2.98-8.57) had significantly higher odds of underestimating their bleeding risk. Conclusions We found that more than two-thirds of patients with atrial fibrillation on oral anticoagulant therapy underestimated their bleeding risk and that participants with a history of bleeding and several comorbid conditions were more likely to underestimate their bleeding risk whereas non-Whites and women were less likely to underestimate their bleeding risk. Clinicians should ensure that patients prescribed oral anticoagulant therapy have a thorough understanding of bleeding risk.

Intrabone infusion for allogeneic umbilical cord blood transplantation in children.

Umbilical cord blood transplantation (UCBT) has been used to treat malignant and non-malignant diseases. UCBT offers the advantages of easy procurement and acceptable partial HLA mismatches, but also shows delayed hematopoietic and immunological recoveries. We postulated that an intrabone (IB) infusion of cord blood could provide a faster short- and long-term engraftment in a pediatric population with malignant and non-malignant hematologic diseases. We conducted this phase I-II single arm, exploratory clinical trial (NCT01711788) from 2012 to 2016 in a single center. Fifteen patients aged from 1.9 to 16.4 years received an IB UCBT. Median time to neutrophils and platelet recoveries were 18 days (range: 13-36 days) and 42 days (range: 26-107 days), respectively. Rate of severe acute GVH grade was low, with only one patient with grade III aGVH. Relapse occurred in 5 patients (38.5%) and TRM occurred in 1 patient. This leads to 6 years EFS and OS of 66.7% and 80% respectively. In conclusion, IB UCBT is safe and well-tolerated in children and hematological recovery compared similarly to the results obtained with IV UCBT.

Multimorbidity, physical frailty, and self-rated health in older patients with atrial fibrillation.

BACKGROUND: Holistic care models emphasize management of comorbid conditions to improve patient-reported outcomes in treatment of atrial fibrillation (AF). We investigated relations between multimorbidity, physical frailty, and self-rated health (SRH) among older adults with AF. METHODS: Patients (n = 1235) with AF aged 65 years and older were recruited from five medical centers in Massachusetts and Georgia between 2015 and 2018. Ten previously diagnosed cardiometabolic and 8 non-cardiometabolic conditions were assessed from medical records. Physical Frailty was assessed with the Cardiovascular Health Study frailty scale. SRH was categorized as either "excellent/very good", "good", and "fair/poor". Separate multivariable ordinal logistic models were used to examine the associations between multimorbidity and SRH, physical frailty and SRH, and multimorbidity and physical frailty. RESULTS: Overall, 16% of participants rated their health as fair/poor and 14% were frail. Hypertension (90%), dyslipidemia (80%), and heart failure (37%) were the most prevalent cardiometabolic conditions. Arthritis (51%), anemia (31%), and cancer (30%), the most common non-cardiometabolic diseases. After multivariable adjustment, patients with higher multimorbidity were more likely to report poorer health status (Odds Ratio (OR): 2.15 [95% CI: 1.53-3.03], ≥ 8 vs 1-4; OR: 1.37 [95% CI: 1.02-1.83], 5-7 vs 1-4), as did those with more prevalent cardiometabolic and non-cardiometabolic conditions. Patients who were pre-frail (OR: 1.73 [95% CI: 1.30-2.30]) or frail (OR: 6.81 [95% CI: 4.34-10.68]) reported poorer health status. Higher multimorbidity was associated with worse frailty status. CONCLUSIONS: Multimorbidity and physical frailty were common and related to SRH. Our findings suggest that holistic management approaches may influence SRH among older patients with AF.

Impact of comorbid conditions on disease-specific quality of life in older men and women with atrial fibrillation.

BACKGROUND: Older persons with atrial fibrillation (AF) experience significant impairment in quality of life (QoL), which may be partly attributable to their comorbid diseases. A greater understanding of the impact of comorbidities on QoL could optimize patient-centered care among older persons with AF. OBJECTIVE: To assess impairment in disease-specific QoL due to comorbid conditions in older adults with AF. METHODS: Patients aged ≥ 65 years diagnosed with AF were recruited from five medical centers in Massachusetts and Georgia between 2015 and 2018. At 1 year of follow-up, the Quality of Life Disease Impact Scale-for Multiple Chronic Conditions was used to provide standardized assessment of patient self-reported impairment in QoL attributable to 34 comorbid conditions grouped in 10 clusters. RESULTS: The mean age of study participants (n = 1097) was 75 years and 48% were women. Overall, cardiometabolic, musculoskeletal, and pulmonary conditions were the most prevalent comorbidity clusters. A high proportion of participants (82%) reported that musculoskeletal conditions exerted the greatest impact on their QoL. Men were more likely than women to report that osteoarthritis and stroke severely impacted their QoL. Patients aged < 75 years were more likely to report that obesity, hip/knee joint problems, and fibromyalgia extremely impacted their QoL than older participants. CONCLUSIONS: Among older persons with AF, while cardiometabolic diseases were highly prevalent, musculoskeletal conditions exerted the greatest impact on patients' disease-specific QoL. Understanding the extent of impairment in QoL due to underlying comorbidities provides an opportunity to develop interventions targeted at diseases that may cause significant impairment in QoL.

Psychosocial and cognitive multimorbidity and health-related quality of life and symptom burden in older adults with atrial fibrillation: The systematic assessment of geriatric elements in atrial fibrillation (SAGE-AF) cohort study.

BACKGROUND: Depression, anxiety, and cognitive impairments occur in up to 40 % of adults with AF and are associated with poorer health-related quality of life (HRQoL) and higher symptom burden. However, it is unknown how often these impairments co-occur, or multimorbidity, and how multimorbidity effects HRQoL and symptom burden. METHODS: Patients with AF age ≥65 years with a CHA2DS2VASC risk score ≥ 2 and eligible for oral anticoagulation therapy were recruited from five clinics in a prospective cohort study. Participants completed validated measures of depression (PHQ9) and anxiety (GAD7), cognitive impairment (MoCA), and HRQOL and AF symptom burden (AFEQT). Multinomial logistic regression was used. RESULTS: Participants (N = 1244, 49 % female) were on average 76 ± 7 years; 86 % were non-Hispanic white. Approximately 35 % of participants had 1 impairment, 17 % had 2 impairments and 8% had 3 impairments; 39 % had none of the 3 impairments examined. Compared to participants with no impairments, patients with 1, 2 and 3 impairments had higher odds of poor HRQoL (adjusted OR [AOR] = 1.77, 95 % CI 1.21, 2.60; AOR = 6.64, 95 % CI 4.43, 9.96; and AOR = 7.50, 95 % CI 4.40, 12.77, respectively) and those with 2 and 3 impairments had higher odds of high symptom burden (AOR = 3.69 95 % CI 2.22, 6.13; and AOR = 5.41 95 % CI 2.85, 10.26). CONCLUSIONS: Psychosocial/cognitive multimorbidity is common among older adults with AF and is associated with poor HRQoL and high symptom burden. Clinicians might consider incorporating psychosocial and cognitive screens into routine care as this may identify a high-risk population.

Multi-laboratory assay for harmonization of enumeration of viable CD34+ and CD45+ cells in frozen cord blood units.

BACKGROUND AIMS: In 2016, specifications for both pre-cryopreserved and post-thawed cord blood were defined in the sixth edition of NetCord Foundation for the Accreditation of Cellular Therapy (FACT) Standards for Cord Blood Banks. However, for several experts, harmonization regarding flow cytometry analysis performed on post-thawed samples is still a concern. A multicenter study led by Héma-Québec aimed to provide scientific data to support the cord blood accreditation bodies such as NetCord FACT in the revision of standards. METHODS: Twelve cord blood units were processed for plasma and red cell reduction following standard operating procedures. Cord blood unit aliquots were shipped to eight participating centers under cryogenic conditions for analysis before and after standardization of protocol. Repeatability of stem cell count, measured pre- and post-intervention with the centers, was estimated using multilevel linear regression models with a heterogeneous compound symmetry correlation structure among repeated measures. RESULTS: Excellent inter-center repeatability was reported by each participant regarding the viable CD34+ cells concentration, and a successful improvement effect of protocol standardization was also observed. However, we observed that better control over the critical parameters of the protocol did not have a significant effect on improving homogeneity in the enumeration of CD45+ cells. CONCLUSIONS: The current practice in cord blood selection should now also consider relying on post-thaw CD34+ concentration, providing that all cord blood banks or outsourcing laboratories in charge of the analysis of post-thaw CB samples take into account the consensual recommendations provided in this work and adhere to a good-quality management system.

NUP98-BPTF gene fusion identified in primary refractory acute megakaryoblastic leukemia of infancy.

The advent of large scale genomic sequencing technologies significantly improved the molecular classification of acute megakaryoblastic leukaemia (AMKL). AMKL represents a subset (∼10%) of high fatality pediatric acute myeloid leukemia (AML). Recurrent and mutually exclusive chimeric gene fusions associated with pediatric AMKL are found in 60%-70% of cases and include RBM15-MKL1, CBFA2T3-GLIS2, NUP98-KDM5A and MLL rearrangements. In addition, another 4% of AMKL harbor NUP98 rearrangements (NUP98r), with yet undetermined fusion partners. We report a novel NUP98-BPTF fusion in an infant presenting with primary refractory AMKL. In this NUP98r, the C-terminal chromatin recognition modules of BPTF, a core subunit of the NURF (nucleosome remodeling factor) ATP-dependent chromatin-remodeling complex, are fused to the N-terminal moiety of NUP98, creating an in frame NUP98-BPTF fusion, with structural homology to NUP98-KDM5A. The leukemic blasts expressed two NUP98-BPTF splicing variants, containing one or two tandemly spaced PHD chromatin reader domains. Our study also identified an unreported wild type BPTF splicing variant encoding for 2 PHD domains, detected both in normal cord blood CD34+ cells and in leukemic blasts, as with the fly BPTF homolog, Nurf301. Disease course was marked by rapid progression and primary chemoresistance, with ultimately significant tumor burden reduction following treatment with a clofarabine containing regimen. In sum, we report 2 novel NUP98-BPTF fusion isoforms that contribute to refine the NUP98r subgroup of pediatric AMKL. Multicenter clinical trials are critically required to determine the frequency of this fusion in AMKL patients and explore innovative treatment strategies for a disease still plagued with poor outcomes.

Human mesenchymal stromal cell-secreted lactate induces M2-macrophage differentiation by metabolic reprogramming.

Human mesenchymal stromal cells (MSC) have been shown to dampen immune response and promote tissue repair, but the underlying mechanisms are still under investigation. Herein, we demonstrate that umbilical cord-derived MSC (UC-MSC) alter the phenotype and function of monocyte-derived dendritic cells (DC) through lactate-mediated metabolic reprogramming. UC-MSC can secrete large quantities of lactate and, when present during monocyte-to-DC differentiation, induce instead the acquisition of M2-macrophage features in terms of morphology, surface markers, migratory properties and antigen presentation capacity. Microarray expression profiling indicates that UC-MSC modify the expression of metabolic-related genes and induce a M2-macrophage expression signature. Importantly, monocyte-derived DC obtained in presence of UC-MSC, polarize naïve allogeneic CD4+ T-cells into Th2 cells. Treatment of UC-MSC with an inhibitor of lactate dehydrogenase strongly decreases lactate concentration in culture supernatant and abrogates the effect on monocyte-to-DC differentiation. Metabolic analysis further revealed that UC-MSC decrease oxidative phosphorylation in differentiating monocytes while strongly increasing the spare respiratory capacity proportional to the amount of secreted lactate. Because both MSC and monocytes are recruited in vivo at the site of tissue damage and inflammation, we propose the local increase of lactate concentration induced by UC-MSC and the consequent enrichment in M2-macrophage generation as a mechanism to achieve immunomodulation.

Cord-blood-derived mesenchymal stromal cells downmodulate CD4+ T-cell activation by inducing IL-10-producing Th1 cells.

The mechanisms by which mesenchymal stromal cells (MSCs) induce immunomodulation are still poorly understood. In the current work, we show by a combination of polymerase chain reaction (PCR) array, flow cytometry, and multiplex cytokine data analysis that during the inhibition of an alloantigen-driven CD4+ T-cell response, MSCs induce a fraction of CD4+ T-cells to coexpress interferon-γ (IFNγ) and interleukin-10 (IL-10). This CD4+ IFNγ+ IL-10+ cell population shares properties with recently described T-cells originating from switched Th1 cells that start producing IL-10 and acquire a regulatory function. Here we report that IL-10-producing Th1 cells accumulated with time during T-cell stimulation in the presence of MSCs. Moreover, MSCs caused stimulated T-cells to downregulate the IFNγ receptor (IFNγR) without affecting IL-10 receptor expression. Further, the inhibitory effect of MSCs could be reversed by an anti-IFNγR-blocking antibody, indicating that IFNγ is one of the major players in MSC-induced T-cell suppression. Stimulated (and, to a lesser extent, resting) CD4+ T-cells treated with MSCs were able to inhibit the proliferation of autologous CD4+ T-cells, demonstrating their acquired regulatory properties. Altogether, our results suggest that the generation of IL-10-producing Th1 cells is one of the mechanisms by which MSCs can downmodulate an immune response.

Impact of storage temperature and processing delays on cord blood quality: discrepancy between functional in vitro and in vivo assays.

BACKGROUND: Optimal conditions of cord blood (CB) storage, processing, cryopreservation, and thawing are critical for banking and transplantation. Nevertheless, standardized procedures are still awaited. STUDY DESIGN AND METHODS: We evaluated the impact of preprocessing storage and temperature on recovery, viability, and functional differentiation capacities of hematopoietic progenitor cells. We compared units stored at room temperature (RT) or at 4 °C for 72 hours before cryopreservation to units processed shortly after collection (<12 hr). RESULTS: Postthaw results showed similar in vitro characteristics between immediate processing and 4 °C storage for cell recovery and viability, both significantly higher than RT storage. Surprisingly, we demonstrated that storage of CB units at RT before processing and cryopreservation profoundly altered in vivo hematopoietic reconstitution in mice, although in vitro hematopoietic colony-forming unit potential was unaltered. CONCLUSION: Our findings challenge current CB storage practices and suggest standard in vitro quality assessments may not always be indicative of CB engraftment potential.

Expression of COX-1 and COX-2 in the endometrium of cyclic, pregnant and in a model of pseudopregnant rats and their regulation by sex steroids.

BACKGROUND: Cyclooxygenases (COXs) are the rate limiting enzymes in the process of prostaglandins (PGs) synthesis, which are critical regulators of a number of reproductive processes, including ovulation, implantation, decidualization and parturition. The aim of the present study was to investigate the expression and regulation of COX-1 and COX-2 and levels of prostaglandins during rat pregnancy, in a model of pseudopregnancy and estrous cycle. METHODS: Uteri were collected from the cyclic rats on each day of estrous cycle, after every two days for pregnant (days 2 to 22) and pseudopregnant rats (days 1 to 9). In vitro primary endometrial stromal cells were cultured in the presence of steroid hormones and their respective inhibitors for the possible modulation of COX-1 and COX-2. Endometrial protein extracts were used for western blot analysis and tissue sections were prepared for protein localization using immunofluorescence. Measurements of PGF2alpha and PGE2 metabolites in serum were performed by enzyme immunoassay (EIA). RESULTS: COX-1 expression was found to be elevated during implantation and parturition, however, the levels of COX-1 decreased during decidualization periods. COX-2 was detected during early pregnancy from day 2 to 5, increased during decidual regression, and was also expressed at the time of parturition. COX-2 protein expression was found to be increased at estrus phase in cyclic rats. Both enzymes were found to be modulated in the endometrium of pseudopregnant rats, suggesting that they are regulated by 17beta-estradiol and progesterone. A significant increase in PGE2 metabolite levels was observed on day 10, 12 and 14 of pregnancy. However, an increase in PGF2alpha metabolite levels was observed only on day 14. The concentration of both these metabolites changed during pseudopregnancy and maximum levels were observed at day 7. Significant increase in PGE2 metabolite was observed at proestrus phase, on the other hand, PGF2alpha metabolite was significantly increased at proestrus and metestrus phase. COX-2 protein was regulated by 17beta-estradiol in cultured endometrial stromal cells which was blocked in the presence of ICI-182,780. CONCLUSIONS: Taken together, these results suggest that COX-1 and COX-2 could be differentially regulated by steroid hormones and might be the key factors involved in embryo implantation, decidualization, decidua basalis regression and parturition in rats.

A mutant allele of the Swi/Snf member BAF250a determines the pool size of fetal liver hemopoietic stem cell populations.

It is believed that hemopoietic stem cells (HSC), which colonize the fetal liver (FL) rapidly, expand to establish a supply of HSCs adequate for maintenance of hemopoiesis throughout life. Accordingly, FL HSCs are actively cycling as opposed to their predominantly quiescent bone marrow counterparts, suggesting that the FL microenvironment provides unique signals that support HSC proliferation and self-renewal. We now report the generation and characterization of mice with a mutant allele of Baf250a lacking exons 2 and 3. Baf250a(E2E3/E2E3) mice are viable until E19.5, but do not survive beyond birth. Most interestingly, FL HSC numbers are markedly higher in these mice than in control littermates, thus raising the possibility that Baf250a determines the HSC pool size in vivo. Limit dilution experiments indicate that the activity of Baf250a(E2E3/E2E3) HSC is equivalent to that of the wild-type counterparts. The Baf250a(E2E3/E2E3) FL-derived stroma, in contrast, exhibits a hemopoiesis-supporting potential superior to the developmentally matched controls. To our knowledge, this demonstration is the first that a mechanism operating in a cell nonautonomous manner canexpand the pool size of the fetal HSC populations.

The signaling protein Wnt4 enhances thymopoiesis and expands multipotent hematopoietic progenitors through beta-catenin-independent signaling.

Despite studies based on deletion or activation of intracellular components of the canonical Wingless related (Wnt) pathway, the role of Wnts in hematolymphopoiesis remains controversial. Using gain-of-function and loss-of-function models, we found that Wnt4 differentially affected diverse subsets of hematopoietic stem and progenitor cells. Bone-marrow and thymic Lin(-)Sca1(+)Kit(hi) cells (LSKs) were the key targets of Wnt4. In adult mice, Wnt4-induced expansion of Flt3(+) bone-marrow LSKs (lymphoid-primed multipotent progenitors) led to a sizeable accumulation of the most immature thymocyte subsets (upstream of beta-selection) and a major increase in thymopoiesis. Conversely, Wnt4(-/-) neonates showed low frequencies of bone-marrow LSKs and thymic hypocellularity. We provide compelling evidence that Wnt4 activates noncanonical (beta-catenin-independent) signaling and that its effects on hematopoietic cells are mainly non-cell-autonomous. Our work shows that Wnt4 overexpression has a unique ability to expand Flt3(+) LSKs in adults and demonstrates that noncanonical Wnt signaling regulates thymopoiesis.