Signaling through the Inhibitory Fc Receptor FcγRIIB Induces CD8+ T Cell Apoptosis to Limit T Cell Immunity.

Effector CD8+ T cells are important mediators of adaptive immunity, and receptor-ligand interactions that regulate their survival may have therapeutic potential. Here, we identified a subset of effector CD8+ T cells that expressed the inhibitory fragment crystallizable (Fc) receptor FcγRIIB following activation and multiple rounds of division. CD8+ T cell-intrinsic genetic deletion of Fcgr2b increased CD8+ effector T cell accumulation, resulting in accelerated graft rejection and decreased tumor volume in mouse models. Immunoglobulin G (IgG) antibody was not required for FcγRIIB-mediated control of CD8+ T cell immunity, and instead, the immunosuppressive cytokine fibrinogen-like 2 (Fgl2) was a functional ligand for FcγRIIB on CD8+ T cells. Fgl2 induced caspase-3/7-mediated apoptosis in Fcgr2b+, but not Fcgr2b-/-, CD8+ T cells. Increased expression of FcγRIIB correlated with freedom from rejection following withdrawal from immunosuppression in a clinical trial of kidney transplant recipients. Together, these findings demonstrate a cell-intrinsic coinhibitory function of FcγRIIB in regulating CD8+ T cell immunity.

Selective whole-genome amplification reveals population genetics of Leishmania braziliensis directly from patient skin biopsies.

In Brazil, Leishmania braziliensis is the main causative agent of the neglected tropical disease, cutaneous leishmaniasis (CL). CL presents on a spectrum of disease severity with a high rate of treatment failure. Yet the parasite factors that contribute to disease presentation and treatment outcome are not well understood, in part because successfully isolating and culturing parasites from patient lesions remains a major technical challenge. Here we describe the development of selective whole genome amplification (SWGA) for Leishmania and show that this method enables culture-independent analysis of parasite genomes obtained directly from primary patient skin samples, allowing us to circumvent artifacts associated with adaptation to culture. We show that SWGA can be applied to multiple Leishmania species residing in different host species, suggesting that this method is broadly useful in both experimental infection models and clinical studies. SWGA carried out directly on skin biopsies collected from patients in Corte de Pedra, Bahia, Brazil, showed extensive genomic diversity. Finally, as a proof-of-concept, we demonstrated that SWGA data can be integrated with published whole genome data from cultured parasite isolates to identify variants unique to specific geographic regions in Brazil where treatment failure rates are known to be high. SWGA provides a relatively simple method to generate Leishmania genomes directly from patient samples, unlocking the potential to link parasite genetics with host clinical phenotypes.

Defining the Need for Services for Patients at High Risk of Breast Cancer at a Safety-Net Hospital: An Approach to Narrowing the Disparities Gap.

BACKGROUND: The National Accreditation Program for Breast Cancer (NAPBC) standards were recently revised to promote breast cancer (BC) risk assessment and subsequent referral for high-risk services. This project sought to estimate the proportion of patients at high risk for BC in the authors' safety-net hospital system, gauge patient interest in high-risk services, and define resources for program development. METHODS: Women presenting for breast imaging during 2 weeks in 2023 were surveyed. Thirty-five patients with a history or diagnosis of BC were excluded. The Tyrer-Cuzick (TC) model version 8 was used to calculate BC risk. High/intermediate risk was defined as a 10-year risk of 5% or more, a lifetime risk of 15% or more, or both. The criteria for genetic counseling and testing referral were based on National Comprehensive Cancer Network guidelines. RESULTS: A total of 257 patients had a TC risk assessment showing 14.8% (n = 38) with a 10-year BC risk of 5% or more (consideration of endocrine therapy), 6.2% (n = 16) with a lifetime BC risk of 20% or more (qualifying for annual screening MRI), and 10.5% (n = 27) with a lifetime BC risk of 15% or more (consideration of high-risk screening). The criteria for genetic counseling/testing were met by 61 (23.7%) of the 257 patients. Overall, 31.5% (n = 81) qualified for high/intermediate-risk screening, risk reduction, and/or genetic assessment/testing, 92.8% of whom were interested in referrals for additional information and care. CONCLUSIONS: In the authors' community, almost one third of patients undergoing breast imaging qualify for BC high-risk assessment and services. The majority of the patients expressed interest in pursuing such services. These data will be used in financial planning and resource allocation to develop a high-risk program at the authors' institution in line with NAPBC guidelines. They are hopeful that these efforts will improve oncologic outcomes and survival from BC in their community.

Updates in diagnosis and treatment of pediatric antiphospholipid syndrome.

PURPOSE OF REVIEW: This review offers an overview of the most important recent articles on pediatric APS. RECENT FINDINGS: Non-thrombotic extra criteria manifestations were prevalent in pediatric APS. Pregnancy morbidity has been described as the first manifestation of APS at youth age, impairing gestational outcomes. The 2023 APS criteria were developed for adult APS patients, and there is still a lack of pediatric-specific APS criteria. Catastrophic APS was more commonly reported as the initial manifestation of pediatric APS than in adults. Regarding treatment, direct oral anticoagulants have been recently approval for pediatric patients with venous thrombosis. New approaches have been proposed for severe cases, for arterial thrombosis, and rituximab for refractory cases. Recurrences typically occurred early and were associated with older age at diagnosis. Current studies highlighted the multifaceted nature of pediatric APS. Further large prospective multicenter studies evaluating new medications capable of reducing recurrence risk and improving prognosis in this population will be required.

Pairs and Pairix: a file format and a tool for efficient storage and retrieval for Hi-C read pairs.

SUMMARY: As the amount of 3D chromosomal interaction data continues to increase, storing and accessing such data efficiently becomes paramount. We introduce Pairs, a block-compressed text file format for storing paired genomic coordinates from Hi-C data, and Pairix, an open-source C application to index and query Pairs files. Pairix (also available in Python and R) extends the functionalities of Tabix to paired coordinates data. We have also developed PairsQC, a collapsible HTML quality control report generator for Pairs files. AVAILABILITY AND IMPLEMENTATION: The format specification and source code are available at https://github.com/4dn-dcic/pairix, https://github.com/4dn-dcic/Rpairix and https://github.com/4dn-dcic/pairsqc.

Comparisons in the Health and Economic Assessments of Using Quadrivalent Versus Trivalent Influenza Vaccines: A Systematic Literature Review.

OBJECTIVES: Seasonal influenza vaccines protect against 3 (trivalent influenza vaccine [IIV3]) or 4 (quadrivalent influenza vaccine [IIV4]) viruses. IIV4 costs more than IIV3, and there is a trade-off between incremental cost and protection. This is especially the case in low- and middle-income countries (LMICs) with limited budgets; previous reviews have not identified studies of IIV4-IIV3 comparisons in LMICs. We summarized the literature that compared health and economic outcomes of IIV4 and IIV3, focused on LMICs. METHODS: We systematically searched 5 databases for articles published before October 6, 2021, that modeled health or economic effects of IIV4 versus IIV3. We abstracted data and compared findings among countries and models. RESULTS: Thirty-eight studies fit our selection criteria; 10 included LMICs. Most studies (N = 31) reported that IIV4 was cost-saving or cost-effective compared with IIV3; we observed no difference in health or economic outcomes between LMICs and other countries. Based on cost differences of influenza vaccines, only one study compared coverage of IIV3 with IIV4 and reported that the maximum IIV4 price that would still yield greater public health impact than IIV3 was 13% to 22% higher than IIV3. CONCLUSIONS: When vaccination coverage with IIV4 and IIV3 is the same, IIV4 tends to be not only more effective but more cost-effective than IIV3, even with relatively high price differences between vaccine types. Alternatively, where funding is limited as in most LMICs, higher vaccine coverage can be achieved with IIV3 than IIV4, which could result in more favorable health and economic outcomes.

Facebook Intervention to Connect Alaska Native People With Resources and Support to Quit Smoking: CAN Quit Pilot Randomized Controlled Trial.

INTRODUCTION: There is some evidence that social media interventions can promote smoking cessation. This randomized controlled pilot study is the first to evaluate the feasibility and potential efficacy of a Facebook smoking cessation intervention among Alaska Native (AN) adults. AIMS AND METHODS: Recruitment and data collection occurred from December 2019 to March 2021. Participants were recruited statewide in Alaska using Facebook advertisements with a targeted sample of 60 enrolled. Participants were stratified by gender, age, and rural or urban residence and randomly assigned to receive referral resources on evidence-based cessation treatments (EBCTs) (control, n = 30) or these resources plus a 3-month, closed (private), culturally tailored, Facebook group (intervention, n = 31) that connected participants to EBCT resources and was moderated by two Alaska Native Trained Tobacco Specialists. Assessments were conducted online post-randomization at 1, 3, and 6 months. Outcomes were feasibility (recruitment, retention, and intervention engagement), self-reported use of EBCTs, and biochemically confirmed seven-day point-prevalence smoking abstinence. RESULTS: Of intervention participants, 90% engaged (eg posted, commented) more than once. Study retention was 57% at 6 months (no group differences). The proportion utilizing EBCTs was about double for intervention compared with the control group participants at 3 and 6 months. Smoking abstinence was higher for intervention than control participants at 3 months (6.5% vs. 0%, p = .16) but comparable at 6 months (6.4% vs. 6.7%, p = .97). CONCLUSIONS: While additional research is needed to promote long-term cessation, this pilot trial supports recruitment feasibility during the Coronavirus Disease 2019 (COVID-19) pandemic, consumer uptake, and a signal for intervention efficacy on the uptake of cessation treatment and short-term smoking abstinence. IMPLICATIONS: This study is the first evaluation of a social media intervention for smoking cessation among Indigenous people. We learned that statewide Facebook recruitment of AN adults who smoke was feasible and there was a signal for the efficacy of a Facebook intervention on the uptake of EBCT and short-term (3 months) biochemically verified smoking abstinence. Clinically, social media platforms may complement current care models by connecting AN individuals and others living in hard-to-reach communities to cessation treatment resources.

Spatial and Temporal analysis (2008-2017) of droughts and their effects on livestock in the Brazilian semi-arid region.

In this study a temporal analysis (2008-2017) was conducted to examine the occurrence of droughts and the spatial distribution of livestock herds in the Brazilian semi-arid region. Maps of vegetation cover, classes of normalized difference vegetation index (NDVI) and normalized difference drought index (NDDI) were used. Image processing took place on the Google Earth Engine platform along with QGIS Software (2.18). Two historical series were created to compare the variation between two herds and the dry monitoring, one called the 1st series (2008-2012) and 2nd series (2013-2017) which were compared using a paired t-test. The comparative analysis showed that the classes of extreme drought and exceptional drought covered the greatest land areas in the 2nd series, while abnormal drought covered the greatest land area in the 1st series. The analysis of herds, a reduction in the cattle herd and an increase in goat and sheep herds were noted. This study considers the efficacy of NDDI and NDVI indices to monitor the distribution of droughts in the Brazilian semi-arid region. The geoprocess of Sidra data enabled an analysis of the spatial distribution and temporal variation of the herds in the semi-arid region and how drought may have impacted livestock dynamics.

CBP/p300 homologs CBP2 and CBP3 play distinct roles in planarian stem cell function.

Chromatin modifications function as critical regulators of gene expression and cellular identity, especially in the regulation and maintenance of the pluripotent state. However, many studies of chromatin modification in stem cells-and pluripotent stem cells in particular-are performed in mammalian stem cell culture, an in vitro condition mimicking a very transient state during mammalian development. Thus, new models for studying pluripotent stem cells in vivo could be helpful for understanding the roles of chromatin modification, for confirming prior in vitro studies, and for exploring evolution of the pluripotent state. The freshwater flatworm, Schmidtea mediterranea, is an excellent model for studying adult pluripotent stem cells, particularly in the context of robust, whole-body regeneration. To identify chromatin modifying and remodeling enzymes critical for planarian regeneration and stem cell maintenance, we took a candidate approach and screened planarian homologs of 25 genes known to regulate chromatin biology in other organisms. Through our study, we identified six genes with novel functions in planarian homeostasis, regeneration, and behavior. Of the list of genes characterized, we identified five planarian homologs of the mammalian CREB-Binding Protein (CBP) and p300 family of histone acetyltransferases, representing an expansion of this family in planarians. We find that two planarian CBP family members are required for planarian survival, with knockdown of Smed-CBP2 and Smed-CBP3 causing distinct defects in stem cell maintenance or function. Loss of CBP2 causes a quick, dramatic loss of stem cells, while knockdown of CBP3 affects stem cells more narrowly, influencing differentiation of several cell types that include neuronal subtypes and cells of the eye. Further, we find that Smed-CBP1 is required for planarian fissioning behavior. We propose that the division of labor among a diversified CBP family in planarians presents an opportunity to dissect specific functions of a broadly important histone acetyltransferase family.

How thermal challenges change gene regulation in the songbird brain and gonad: Implications for sexual selection in our changing world.

In a rapidly warming world, exposure to high temperatures may impact fitness, but the gene regulatory mechanisms that link sublethal heat to sexually selected traits are not well understood, particularly in endothermic animals. Our experiment used zebra finches (Taeniopygia guttata), songbirds that experience extreme temperature fluctuations in their native Australia. We exposed captive males to an acute thermal challenge (43°C) compared with thermoneutral (35°C) and lower (27°C) temperatures. We found significantly more heat dissipation behaviours at 43°C, a temperature previously shown to reduce song production and fertility, and more heat retention behaviours at 27°C. Next, we characterized transcriptomic responses in tissues important for mating effort-the posterior telencephalon, for its role in song production, and the testis, for its role in fertility and hormone production. Differential expression of hundreds of genes in the testes, but few in the brain, suggests the brain is less responsive to extreme temperatures. Nevertheless, gene network analyses revealed that expression related to dopaminergic signalling in the brain covaried with heat dissipation behaviours, providing a mechanism by which temporary thermal challenges may alter motivational circuits for song production. In both brain and testis, we observed correlations between thermally sensitive gene networks and individual differences in thermoregulatory behaviour. Although we cannot directly relate these gene regulatory changes to mating success, our results suggest that individual variation in response to thermal challenges could impact sexually selected traits in a warming world.