IL-10 Is Critical for Regulation of Cytotoxic CD4+NKG7+ T Cells in Lung Allograft Rejection but Is Not Required for Allograft Acceptance.

Lung transplant remains the primary therapeutic option for patients with end-stage lung disease, but long-term survival rates remain suboptimal compared with other solid organ transplants. Acute cellular rejection (ACR) is a significant challenge in lung transplant recipients, with T cell-mediated mechanisms playing a major role. IL-10 is known for its immunoregulatory function, although its specific role in lung allograft rejection remains unclear. Using the mouse orthotopic lung transplant model, we investigated the role of IL-10 in regulating alloeffector T cell responses. Unexpectedly, we found that IL-10 was not required for early costimulation blockade-induced allograft acceptance. However, IL-10 deficiency or blockade resulted in increased CD4+ T cell numbers, proliferation, graft infiltration, and alloeffector responses. In the absence of IL-10, CD4+ T cell responses predominated over CD8 responses during ACR in contrast to wild-type mice. Type 1 immunity (IFN-γ) responses along with elevated CD4+NKG7+ and CD4+CD107a+ responses predominated during ACR, highlighting a critical regulatory role for IL-10 in modulating CD4+ T cell alloimmune responses. We further demonstrated increased colocalization of NKG7 and CD107a in CD4+ T cells from IL-10-deficient allografts, suggesting coordination in cytotoxic activity. Together, our findings highlight a critical role for IL-10 in regulation of cytotoxic CD4+NKG7+ T cells, an effector population that needs further investigation to elucidate their role in lung allograft rejection.

CD4+ T-Cell Dysfunction in Severe COVID-19 Disease Is Tumor Necrosis Factor-α/Tumor Necrosis Factor Receptor 1-Dependent.

Rationale: Lymphopenia is common in severe coronavirus disease (COVID-19), yet the immune mechanisms are poorly understood. As inflammatory cytokines are increased in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we hypothesized a role in contributing to reduced T-cell numbers. Objectives: We sought to characterize the functional SARS-CoV-2 T-cell responses in patients with severe versus recovered, mild COVID-19 to determine whether differences were detectable. Methods: Using flow cytometry and single-cell RNA sequence analyses, we assessed SARS-CoV-2-specific responses in our cohort. Measurements and Main Results: In 148 patients with severe COVID-19, we found lymphopenia was associated with worse survival. CD4+ lymphopenia predominated, with lower CD4+/CD8+ ratios in severe COVID-19 compared with patients with mild disease (P < 0.0001). In severe disease, immunodominant CD4+ T-cell responses to Spike-1 (S1) produced increased in vitro TNF-α (tumor necrosis factor-α) but demonstrated impaired S1-specific proliferation and increased susceptibility to activation-induced cell death after antigen exposure. CD4+TNF-α+ T-cell responses inversely correlated with absolute CD4+ counts from patients with severe COVID-19 (n = 76; R = -0.797; P < 0.0001). In vitro TNF-α blockade, including infliximab or anti-TNF receptor 1 antibodies, strikingly rescued S1-specific CD4+ T-cell proliferation and abrogated S1-specific activation-induced cell death in peripheral blood mononuclear cells from patients with severe COVID-19 (P < 0.001). Single-cell RNA sequencing demonstrated marked downregulation of type-1 cytokines and NFκB signaling in S1-stimulated CD4+ cells with infliximab treatment. We also evaluated BAL and lung explant CD4+ T cells recovered from patients with severe COVID-19 and observed that lung T cells produced higher TNF-α compared with peripheral blood mononuclear cells. Conclusions: Together, our findings show CD4+ dysfunction in severe COVID-19 is TNF-α/TNF receptor 1-dependent through immune mechanisms that may contribute to lymphopenia. TNF-α blockade may be beneficial in severe COVID-19.

Overall survival in patients with pancreatic cancer receiving matched therapies following molecular profiling: a retrospective analysis of the Know Your Tumor registry trial.

BACKGROUND: About 25% of pancreatic cancers harbour actionable molecular alterations, defined as molecular alterations for which there is clinical or strong preclinical evidence of a predictive benefit from a specific therapy. The Know Your Tumor (KYT) programme includes US patients with pancreatic cancer and enables patients to undergo commercially available multi-omic profiling to provide molecularly tailored therapy options and clinical trial recommendations. We sought to determine whether patients with pancreatic cancer whose tumours harboured such actionable molecular alterations and who received molecularly matched therapy had a longer median overall survival than similar patients who did not receive molecularly matched therapy. METHODS: In this retrospective analysis, treatment history and longitudinal survival outcomes were analysed in patients aged 18 years or older with biopsy-confirmed pancreatic cancer of any stage, enrolled in the KYT programme and who received molecular testing results. Since the timing of KYT enrolment varied for each patient, the primary outcome measurement of median overall survival was calculated from the initial diagnosis of advanced disease until death. We compared median overall survival in patients with actionable mutations who were treated with a matched therapy versus those who were not treated with a matched therapy. FINDINGS: Of 1856 patients with pancreatic cancer who were referred to the KYT programme between June 16, 2014, and March 31, 2019, 1082 (58%) patients received personalised reports based on their molecular testing results. Actionable molecular alterations were identified in 282 (26%) of 1082 samples. Among 677 patients for whom outcomes were available, 189 had actionable molecular alterations. With a median follow-up of 383 days (IQR 214-588), those patients with actionable molecular alterations who received a matched therapy (n=46) had significantly longer median overall survival than did those patients who only received unmatched therapies (n=143; 2·58 years [95% CI 2·39 to not reached] vs 1·51 years [1·33-1·87]; hazard ratio 0·42 [95% CI 0·26-0·68], p=0·0004). The 46 patients who received a matched therapy also had significantly longer overall survival than the 488 patients who did not have an actionable molecular alteration (2·58 years [95% CI 2·39 to not reached] vs 1·32 years [1·25-1·47]; HR 0·34 [95% CI 0·22-0·53], p<0·0001). However, median overall survival did not differ between the patients who received unmatched therapy and those without an actionable molecular alteration (HR 0·82 [95% CI 0·64-1·04], p=0·10). INTERPRETATION: These real-world outcomes suggest that the adoption of precision medicine can have a substantial effect on survival in patients with pancreatic cancer, and that molecularly guided treatments targeting oncogenic drivers and the DNA damage response and repair pathway warrant further prospective evaluation. FUNDING: Pancreatic Cancer Action Network and Perthera.

Transmission characteristics of the 2009 H1N1 influenza pandemic: comparison of 8 Southern hemisphere countries.

While in Northern hemisphere countries, the pandemic H1N1 virus (H1N1pdm) was introduced outside of the typical influenza season, Southern hemisphere countries experienced a single wave of transmission during their 2009 winter season. This provides a unique opportunity to compare the spread of a single virus in different countries and study the factors influencing its transmission. Here, we estimate and compare transmission characteristics of H1N1pdm for eight Southern hemisphere countries/states: Argentina, Australia, Bolivia, Brazil, Chile, New Zealand, South Africa and Victoria (Australia). Weekly incidence of cases and age-distribution of cumulative cases were extracted from public reports of countries' surveillance systems. Estimates of the reproduction numbers, R(0), empirically derived from the country-epidemics' early exponential phase, were positively associated with the proportion of children in the populations (p = 0.004). To explore the role of demography in explaining differences in transmission intensity, we then fitted a dynamic age-structured model of influenza transmission to available incidence data for each country independently, and for all the countries simultaneously. Posterior median estimates of R0 ranged 1.2-1.8 for the country-specific fits, and 1.29-1.47 for the global fits. Corresponding estimates for overall attack-rate were in the range 20-50%. All model fits indicated a significant decrease in susceptibility to infection with age. These results confirm the transmissibility of the 2009 H1N1 pandemic virus was relatively low compared with past pandemics. The pattern of age-dependent susceptibility found confirms that older populations had substantial--though partial--pre-existing immunity, presumably due to exposure to heterologous influenza strains. Our analysis indicates that between-country-differences in transmission were at least partly due to differences in population demography.

COVID-19 convalescent plasma boosts early antibody titer and does not influence the adaptive immune response.

Multiple randomized, controlled clinical trials have yielded discordant results regarding the efficacy of convalescent plasma in outpatients, with some showing an approximately 2-fold reduction in risk and others showing no effect. We quantified binding and neutralizing antibody levels in 492 of the 511 participants from the Clinical Trial of COVID-19 Convalescent Plasma in Outpatients (C3PO) of a single unit of COVID-19 convalescent plasma (CCP) versus saline infusion. In a subset of 70 participants, peripheral blood mononuclear cells were obtained to define the evolution of B and T cell responses through day 30. Binding and neutralizing antibody responses were approximately 2-fold higher 1 hour after infusion in recipients of CCP compared with saline plus multivitamin, but levels achieved by the native immune system by day 15 were almost 10-fold higher than those seen immediately after CCP administration. Infusion of CCP did not block generation of the host antibody response or skew B or T cell phenotype or maturation. Activated CD4+ and CD8+ T cells were associated with more severe disease outcome. These data show that CCP leads to a measurable boost in anti-SARS-CoV-2 antibodies but that the boost is modest and may not be sufficient to alter disease course.

Retrospective Case Series Analysis of RAF Family Alterations in Pancreatic Cancer: Real-World Outcomes From Targeted and Standard Therapies.

PURPOSE: In pancreatic cancer (PC), the RAF family alterations define a rare subset of patients that may predict response to inhibition of the BRAF/MEK/ERK signaling pathway. A comprehensive understanding of the molecular and clinical characteristics of RAF-mutated PC may support future development of RAF-directed strategies. METHODS: Clinical outcomes were assessed across a multi-institutional case series of 81 patients with RAF family-mutated PC. Mutational subgroups were defined on the basis of RAF alteration hotspots and therapeutic implications. RESULTS: The frequency of RAF alterations in PC was 2.2% (84 of 3,781) within a prevalence cohort derived from large molecular databases where BRAF V600E (Exon 15), BRAF ΔNVTAP (Exon 11), and SND1-BRAF fusions were the most common variants. In our retrospective case series, we identified 17 of 81 (21.0%) molecular profiles with a BRAF V600/Exon 15 mutation without any confounding drivers, 25 of 81 (30.9%) with BRAF or RAF1 fusions, and 18 of 81 (22.2%) with Exon 11 mutations. The remaining 21 of 81 (25.9%) profiles had atypical RAF variants and/or multiple oncogenic drivers. Clinical benefit from BRAF/MEK/ERK inhibitors was observed in 3 of 3 subjects within the V600 subgroup (two partial responses), 4 of 6 with fusions (two partial responses), 2 of 6 with Exon 11 mutations (one partial response), and 0 of 3 with confounding drivers. Outcomes analyses also suggested a trend favoring fluorouracil-based regimens over gemcitabine/nab-paclitaxel within the fusion subgroup (P = .027). CONCLUSION: Prospective evaluation of RAF-directed therapies is warranted in RAF-mutated PC; however, differential responses to targeted agents or standard regimens for each mutational subgroup should be a consideration when designing clinical trials.

Submicroscopic infection in Plasmodium falciparum-endemic populations: a systematic review and meta-analysis.

INTRODUCTION: Light microscopy examination of blood slides is the main method of detecting malaria infection; however, it has limited sensitivity. Low-density infections are most likely to be missed, but they contribute to the infectious reservoir. Quantifying these submicroscopic infections is therefore key to understanding transmission dynamics and successfully reducing parasite transmission. METHODS: We conducted a systematic review of endemic population surveys in which P. falciparum prevalence had been measured by both microscopy and a more-sensitive polymerase chain reaction (PCR)-based technique. The combined microscopy:PCR prevalence ratio was estimated by random-effects meta-analysis, and the effect of covariates was determined by meta-regression. RESULTS: Seventy-two pairs of prevalence measurements were included in the study. The prevalence of infection measured by microscopy was, on average, 50.8% (95% confidence interval [CI], 45.2%-57.1%) of that measured by PCR. For gametocyte-specific detection, the microscopy prevalence was, on average, 8.7% (95% CI, 2.8%-26.6%) of the prevalence measured by PCR. A significantly higher percentage of total infections was detected by microscopy in areas of high, compared with low, transmission (74.5% when the prevalence determined by PCR was >75% versus 12.0% when the prevalence determined by PCR was <10%). DISCUSSION: Microscopy can miss a substantial proportion of P. falciparum infections in surveys of endemic populations, especially in areas with low transmission of infection. The extent of the submicroscopic reservoir needs to be taken into account for effective surveillance and control.

Homozygosity and risk of childhood death due to invasive bacterial disease.

BACKGROUND: Genetic heterozygosity is increasingly being shown to be a key predictor of fitness in natural populations, both through inbreeding depression, inbred individuals having low heterozygosity, and also through chance linkage between a marker and a gene under balancing selection. One important component of fitness that is often highlighted is resistance to parasites and other pathogens. However, the significance of equivalent loci in human populations remains unclear. Consequently, we performed a case-control study of fatal invasive bacterial disease in Kenyan children using a genome-wide screen with microsatellite markers. METHODS: 148 cases, comprising children aged <13 years who died of invasive bacterial disease, (variously, bacteraemia, bacterial meningitis or neonatal sepsis) and 137 age-matched, healthy children were sampled in a prospective study conducted at Kilifi District Hospital, Kenya. Samples were genotyped for 134 microsatellite markers using the ABI LD20 marker set and analysed for an association between homozygosity and mortality. RESULTS: At five markers homozygosity was strongly associated with mortality (odds ratio range 4.7 - 12.2) with evidence of interactions between some markers. Mortality was associated with different non-overlapping marker groups in Gram positive and Gram negative bacterial disease. Homozygosity at susceptibility markers was common (prevalence 19-49%) and, with the large effect sizes, this suggests that bacterial disease mortality may be strongly genetically determined. CONCLUSION: Balanced polymorphisms appear to be more widespread in humans than previously appreciated and play a critical role in modulating susceptibility to infectious disease. The effect sizes we report, coupled with the stochasticity of exposure to pathogens suggests that infection and mortality are far from random due to a strong genetic basis.

Consanguinity and susceptibility to infectious diseases in humans.

Studies of animal populations suggest that low genetic heterozygosity is an important risk factor for infection by a diverse range of pathogens, but relatively little research has looked to see whether similar patterns exist in humans. We have used microsatellite genome screen data for tuberculosis (TB), hepatitis and leprosy to test the hypothesis that inbreeding depression increases risk of infection. Our results indicate that inbred individuals are more common among our infected cases for TB and hepatitis, but only in populations where consanguineous marriages are common. No effect was found either for leprosy, which is thought to be oligogenic, or for hepatitis in Italy where consanguineous marriages are rare. Our results suggest that consanguinity is an important risk factor in susceptibility to infectious diseases in humans.

Outcomes in Patients With Pancreatic Adenocarcinoma With Genetic Mutations in DNA Damage Response Pathways: Results From the Know Your Tumor Program.

PURPOSE: Up to 25% of pancreatic adenocarcinomas (PDACs) harbor mutations in the homologous recombination DNA damage response (HR-DDR) pathway. Although known to affect responsiveness to DNA-damaging chemotherapy, the prognostic relevance of these mutations is unclear and outcomes in patients with PDAC who harbor HR-DDR mutations beyond BRCA1/2 remain unexplored. METHODS: We evaluated 820 patients with PDAC enrolled in the Know Your Tumor program for whom we had collected comprehensive genomic testing results and longitudinal clinical outcomes. Patients were categorized as having resected versus advanced disease, and as having received platinum-based therapy versus being platinum naïve. Tumor genomic profiles were categorized as HR-DDR mutated (HR-DDRmut) or proficient (pHR-DDR) on the basis of the presence of pathogenic mutations of somatic or germline origin in BRCA1/2 or PALB2 (group 1); ATM/ATR/ATRX (group 2); or BAP1, BARD1, BRIP1, CHEK1/2, RAD50/51/51B, or FANCA/C/D2/E/F/G/L (group 3). Overall survival was measured from the date of diagnosis until death. RESULTS: Median overall survival (mOS) was similar in all resected patients irrespective of exposure to platinum-based therapy, whereas for platinum-treated patients with advanced disease, mOS was significantly longer for HR-DDRmut versus pHR-DDR (2.37 years v 1.45 years, respectively). Of importance, no difference was identified in platinum-naïve patients. mOS in patients with mutations in all three HR-DDRmut groups was greater than that for pHR-DDR patients, but this difference was lost in platinum-naïve patients. CONCLUSION: Patients with advanced HR-DDRmut have improved mOS when treated with platinum-based therapy compared with pHR-DDR patients. In platinum-naïve patients, there is no mOS difference, which suggests that HR-DDR status has no pure prognostic value. These findings support the need to test all patients with advanced PDAC to ensure that HR-DDRmut patients receive the benefit of treatment with platinum-based therapy.

Stereotype Threat Effects on Learning From a Cognitively Demanding Mathematics Lesson.

Stereotype threat-a situational context in which individuals are concerned about confirming a negative stereotype-is often shown to impact test performance, with one hypothesized mechanism being that cognitive resources are temporarily co-opted by intrusive thoughts and worries, leading individuals to underperform despite high content knowledge and ability (see Schmader & Beilock, ). We test here whether stereotype threat may also impact initial student learning and knowledge formation when experienced prior to instruction. Predominantly African American fifth-grade students provided either their race or the date before a videotaped, conceptually demanding mathematics lesson. Students who gave their race retained less learning over time, enjoyed the lesson less, reported a diminished desire to learn more, and were less likely to choose to engage in an optional math activity. The detrimental impact was greatest among students with high baseline cognitive resources. While stereotype threat has been well documented to harm test performance, the finding that effects extend to initial learning suggests that stereotype threat's contribution to achievement gaps may be greatly underestimated.

Executive Function in Learning Mathematics by Comparison: Incorporating Everyday Classrooms into the Science of Learning.

Individual differences in Executive Function (EF) are well established to be related to overall mathematics achievement, yet the mechanisms by which this occurs are not well understood. Comparing representations (problems, solutions, concepts) is central to mathematical thinking, and relational reasoning is known to rely upon EF resources. The current manuscript explored whether individual differences in EF predicted learning from a conceptually demanding mathematics lesson that required relational reasoning. Analyses revealed that variations in EF predicted learning when measured at a delay, controlling for pretest scores. Thus, EF capacity may impact students' overall mathematics achievement by constraining their resources available to learn from cognitively demanding reasoning opportunities in everyday lessons. To assess the ecological validity of this interpretation, we report follow-up interviews with mathematics teachers who raised similar concerns that cognitively demanding activities such as comparing multiple representations in mathematics may differentially benefit their high versus struggling learners. Broader implications for ensuring that all students have access to, and benefit from, conceptually rich mathematics lessons are discussed. We also highlight the utility of integrating methods in Science of Learning (SL) research.

Molecular Profiling of Patients with Pancreatic Cancer: Initial Results from the Know Your Tumor Initiative.

Purpose: To broaden access to and implementation of precision medicine in the care of patients with pancreatic cancer, the Know Your Tumor (KYT) program was initiated using a turn-key precision medicine system. Patients undergo commercially available multiomic profiling to determine molecularly rationalized clinical trials and off-label therapies.Experimental Design: Tumor samples were obtained for 640 patients from 287 academic and community practices covering 44 states. College of American Pathologists/Clinical Laboratory Improvement Amendments-accredited laboratories were used for genomic, proteomic, and phosphoprotein-based molecular profiling.Results: Tumor samples were adequate for next-generation sequencing in 96% and IHC in 91% of patients. A tumor board reviewed the results for every patient and found actionable genomic alterations in 50% of patients (with 27% highly actionable) and actionable proteomic alterations (excluding chemopredictive markers) in 5%. Actionable alterations commonly found were in DNA repair genes (BRCA1/2 or ATM mutations, 8.4%) and cell-cycle genes (CCND1/2/3 or CDK4/6 alterations, 8.1%). A subset of samples was assessed for actionable phosphoprotein markers. Among patients with highly actionable biomarkers, those who received matched therapy (n = 17) had a significantly longer median progression-free survival (PFS) than those who received unmatched therapy [n = 18; PFS = 4.1 vs. 1.9 months; HR, 0.47; 95% confidence interval (CI): 0.24-0.94; P adj = 0.03].Conclusions: A comprehensive precision medicine system can be implemented in community and academic settings, with highly actionable findings observed in over 25% of pancreatic cancers. Patients whose tumors have highly actionable alterations and receive matched therapy demonstrated significantly increased PFS. Our findings support further prospective evaluation of precision oncology in pancreatic cancer. Clin Cancer Res; 24(20); 5018-27. ©2018 AACR.

Human migration, mosquitoes and the evolution of Plasmodium falciparum.

To date, coalescent analysis of the Plasmodium falciparum genome sequence has failed to provide a unifying theory regarding the parasite's evolution. While a better understanding of the evolution of the malaria genome will undoubtedly clarify the current controversy, the importance of the parasite's interplay with both the human host and mosquito vector cannot be underestimated. Changes in the population biology or ecology of either one of these species have consequences for malaria transmission and this was never more apparent than in the environmental changes brought about by the advent of agriculture.

Psychosocial factors related to job stress and women in management.

This literature review explores women in management and how the psychosocial factors they face in the workplace affect their job-related stress level. The psychosocial factors identified include tokenism, sexual harassment and discrimination, work-family conflict, and workload. Various studies are cited and solutions to decrease job-related stress level are included.

Pandemic potential of a strain of influenza A (H1N1): early findings.

A novel influenza A (H1N1) virus has spread rapidly across the globe. Judging its pandemic potential is difficult with limited data, but nevertheless essential to inform appropriate health responses. By analyzing the outbreak in Mexico, early data on international spread, and viral genetic diversity, we make an early assessment of transmissibility and severity. Our estimates suggest that 23,000 (range 6000 to 32,000) individuals had been infected in Mexico by late April, giving an estimated case fatality ratio (CFR) of 0.4% (range: 0.3 to 1.8%) based on confirmed and suspected deaths reported to that time. In a community outbreak in the small community of La Gloria, Veracruz, no deaths were attributed to infection, giving an upper 95% bound on CFR of 0.6%. Thus, although substantial uncertainty remains, clinical severity appears less than that seen in the 1918 influenza pandemic but comparable with that seen in the 1957 pandemic. Clinical attack rates in children in La Gloria were twice that in adults (<15 years of age: 61%; >/=15 years: 29%). Three different epidemiological analyses gave basic reproduction number (R0) estimates in the range of 1.4 to 1.6, whereas a genetic analysis gave a central estimate of 1.2. This range of values is consistent with 14 to 73 generations of human-to-human transmission having occurred in Mexico to late April. Transmissibility is therefore substantially higher than that of seasonal flu, and comparable with lower estimates of R0 obtained from previous influenza pandemics.

ENVIRONMENTAL STRESS AND THE MAINTENANCE OF SEX IN A FRESHWATER SNAIL.

Synergism among mutations can lead to an advantage to sexual reproduction, provided mutation rates are high enough (the mutational deterministic hypothesis). Here we tested the idea that competition for food can increase the advantage to sexual reproduction, perhaps by increasing the synergism among mutations in asexual individuals. We compared the survivorship of sexual and asexual snails (Potamopyrgus antipodarum) under two treatments: starved and fed. We predicted higher mortality for asexual snails when starved, but found that sexual and asexual individuals survived at the same rate, independent of treatment. These results suggest that the distribution of sex in this snail may not be explained by variation in competition among populations.