Exhausted intratumoral Vδ2- γδ T cells in human kidney cancer retain effector function.

Gamma delta (γδ) T cells reside within human tissues including tumors, but their function in mediating antitumor responses to immune checkpoint inhibition is unknown. Here we show that kidney cancers are infiltrated by Vδ2- γδ T cells, with equivalent representation of Vδ1+ and Vδ1- cells, that are distinct from γδ T cells found in normal human tissues. These tumor-resident Vδ2- T cells can express the transcriptional program of exhausted αß CD8+ T cells as well as canonical markers of terminal T-cell exhaustion including PD-1, TIGIT and TIM-3. Although Vδ2- γδ T cells have reduced IL-2 production, they retain expression of cytolytic effector molecules and co-stimulatory receptors such as 4-1BB. Exhausted Vδ2- γδ T cells are composed of three distinct populations that lack TCF7, are clonally expanded and express cytotoxic molecules and multiple Vδ2- T-cell receptors. Human tumor-derived Vδ2- γδ T cells maintain cytotoxic function and pro-inflammatory cytokine secretion in vitro. The transcriptional program of Vδ2- T cells in pretreatment tumor biopsies was used to predict subsequent clinical responses to PD-1 blockade in patients with cancer. Thus, Vδ2- γδ T cells within the tumor microenvironment can contribute to antitumor efficacy.

Tissue Determinants of Human NK Cell Development, Function, and Residence.

Immune responses in diverse tissue sites are critical for protective immunity and homeostasis. Here, we investigate how tissue localization regulates the development and function of human natural killer (NK) cells, innate lymphocytes important for anti-viral and tumor immunity. Integrating high-dimensional analysis of NK cells from blood, lymphoid organs, and mucosal tissue sites from 60 individuals, we identify tissue-specific patterns of NK cell subset distribution, maturation, and function maintained across age and between individuals. Mature and terminally differentiated NK cells with enhanced effector function predominate in blood, bone marrow, spleen, and lungs and exhibit shared transcriptional programs across sites. By contrast, precursor and immature NK cells with reduced effector capacity populate lymph nodes and intestines and exhibit tissue-resident signatures and site-specific adaptations. Together, our results reveal anatomic control of NK cell development and maintenance as tissue-resident populations, whereas mature, terminally differentiated subsets mediate immunosurveillance through diverse peripheral sites. VIDEO ABSTRACT.

Mapping human haematopoietic stem cells from haemogenic endothelium to birth.

The ontogeny of human haematopoietic stem cells (HSCs) is poorly defined owing to the inability to identify HSCs as they emerge and mature at different haematopoietic sites1. Here we created a single-cell transcriptome map of human haematopoietic tissues from the first trimester to birth and found that the HSC signature RUNX1+HOXA9+MLLT3+MECOM+HLF+SPINK2+ distinguishes HSCs from progenitors throughout gestation. In addition to the aorta-gonad-mesonephros region, nascent HSCs populated the placenta and yolk sac before colonizing the liver at 6 weeks. A comparison of HSCs at different maturation stages revealed the establishment of HSC transcription factor machinery after the emergence of HSCs, whereas their surface phenotype evolved throughout development. The HSC transition to the liver marked a molecular shift evidenced by suppression of surface antigens reflecting nascent HSC identity, and acquisition of the HSC maturity markers CD133 (encoded by PROM1) and HLA-DR. HSC origin was tracked to ALDH1A1+KCNK17+ haemogenic endothelial cells, which arose from an IL33+ALDH1A1+ arterial endothelial subset termed pre-haemogenic endothelial cells. Using spatial transcriptomics and immunofluorescence, we visualized this process in ventrally located intra-aortic haematopoietic clusters. The in vivo map of human HSC ontogeny validated the generation of aorta-gonad-mesonephros-like definitive haematopoietic stem and progenitor cells from human pluripotent stem cells, and serves as a guide to improve their maturation to functional HSCs.

Brigatinib versus Crizotinib in ALK-Positive Non-Small-Cell Lung Cancer.

BACKGROUND: Brigatinib, a next-generation anaplastic lymphoma kinase (ALK) inhibitor, has robust efficacy in patients with ALK-positive non-small-cell lung cancer (NSCLC) that is refractory to crizotinib. The efficacy of brigatinib, as compared with crizotinib, in patients with advanced ALK-positive NSCLC who have not previously received an ALK inhibitor is unclear. METHODS: In an open-label, phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with advanced ALK-positive NSCLC who had not previously received ALK inhibitors to receive brigatinib at a dose of 180 mg once daily (with a 7-day lead-in period at 90 mg) or crizotinib at a dose of 250 mg twice daily. The primary end point was progression-free survival as assessed by blinded independent central review. Secondary end points included the objective response rate and intracranial response. The first interim analysis was planned when approximately 50% of 198 expected events of disease progression or death had occurred. RESULTS: A total of 275 patients underwent randomization; 137 were assigned to brigatinib and 138 to crizotinib. At the first interim analysis (99 events), the median follow-up was 11.0 months in the brigatinib group and 9.3 months in the crizotinib group. The rate of progression-free survival was higher with brigatinib than with crizotinib (estimated 12-month progression-free survival, 67% [95% confidence interval {CI}, 56 to 75] vs. 43% [95% CI, 32 to 53]; hazard ratio for disease progression or death, 0.49 [95% CI, 0.33 to 0.74]; P<0.001 by the log-rank test). The confirmed objective response rate was 71% (95% CI, 62 to 78) with brigatinib and 60% (95% CI, 51 to 68) with crizotinib; the confirmed rate of intracranial response among patients with measurable lesions was 78% (95% CI, 52 to 94) and 29% (95% CI, 11 to 52), respectively. No new safety concerns were noted. CONCLUSIONS: Among patients with ALK-positive NSCLC who had not previously received an ALK inhibitor, progression-free survival was significantly longer among patients who received brigatinib than among those who received crizotinib. (Funded by Ariad Pharmaceuticals; ALTA-1L ClinicalTrials.gov number, NCT02737501 .).

Efficient generation of human NOTCH ligand-expressing haemogenic endothelial cells as infrastructure for in vitro haematopoiesis and lymphopoiesis.

Arterial endothelial cells (AECs) are the founder cells for intraembryonic haematopoiesis. Here, we report a method for the efficient generation of human haemogenic DLL4+ AECs from pluripotent stem cells (PSC). Time-series single-cell RNA-sequencing reveals the dynamic evolution of haematopoiesis and lymphopoiesis, generating cell types with counterparts present in early human embryos, including stages marked by the pre-haematopoietic stem cell genes MECOM/EVI1, MLLT3 and SPINK2. DLL4+ AECs robustly support lymphoid differentiation, without the requirement for exogenous NOTCH ligands. Using this system, we find IL7 acts as a morphogenic factor determining the fate choice between the T and innate lymphoid lineages and also plays a role in regulating the relative expression level of RAG1. Moreover, we document a developmental pathway by which human RAG1+ lymphoid precursors give rise to the natural killer cell lineage. Our study describes an efficient method for producing lymphoid progenitors, providing insights into their endothelial and haematopoietic ontogeny, and establishing a platform to investigate the development of the human blood system.

Using Unannounced Standardized Patients to Assess Clinician Telehealth and Communication Skills at an Urban Student Health Center.

PURPOSE: As the COVID-19 pandemic forced most colleges and universities to go online, student health centers rapidly shifted to telehealth platforms without frameworks for virtual care provision. An urban student health center implemented a needs assessment involving unannounced standardized patients (USPs) to evaluate the integration of a new telehealth workflow and clinicians' virtual communication skills. METHODS: From April to May 2021, USPs conducted two video visits with 12 primary care and four women's health clinicians (N = 16 clinicians; 32 visits). Cases included (1) a 21-year-old female presenting for birth control with a positive Patient Health Questionaire-9 and (2) a 21-year-old male, who vapes regularly, with questions regarding safe sex with men. Clinicians were evaluated using a checklist completed by the USP immediately following the visit and a systematic chart review of the electronic health record. RESULTS: USP feedback indicates most clinicians received high ratings for general communication skills but may benefit from educational intervention in several key telemedicine skills. Clinicians struggled with using nonverbal signals to enrich communication (47% well done), acknowledging emotions (34% well done), and using video for information gathering (34% well done). Low rates of standard screenings (e.g., 63% administered the PHQ-2, <50% asked about alcohol use) suggested protocols for in-person care were not easily incorporated into telehealth practices, and clinicians may benefit from enhanced care team support. Performance reports were shared with clinicians and leadership postvisit. DISCUSSION: Results suggest project design and implementation is scalable and feasible for use at other institutions, offering a structured methodology that can improve general student health care.

Long-term engrafting multilineage hematopoietic cells differentiated from human induced pluripotent stem cells.

Hematopoietic stem cells (HSCs) derived from human induced pluripotent stem cells (iPS cells) have important biomedical applications. We identified differentiation conditions that generate HSCs defined by robust long-term multilineage engraftment in immune-deficient NOD,B6.Prkdcscid Il2rgtm1Wjl/SzJ KitW41/W41 mice. We guided differentiating iPS cells, as embryoid bodies in a defined culture medium supplemented with retinyl acetate, through HOXA-patterned mesoderm to hemogenic endothelium specified by bone morphogenetic protein 4 and vascular endothelial growth factor (VEGF). Removal of VEGF facilitated an efficient endothelial-to-hematopoietic transition, evidenced by release into the culture medium of CD34+ blood cells, which were cryopreserved. Intravenous transplantation of two million thawed CD34+ cells differentiated from four independent iPS cell lines produced multilineage bone marrow engraftment in 25-50% of immune-deficient recipient mice. These functionally defined, multipotent CD34+ hematopoietic cells, designated iPS cell-derived HSCs (iHSCs), produced levels of engraftment similar to those achieved following umbilical cord blood transplantation. Our study provides a step toward the goal of generating HSCs for clinical translation.

mRNA Delivery and Storage by Co-Assembling Nanostructures with Designer Oligopeptides.

Broadening the applicable tools for mRNA delivery provides more flexibility in research and those proven effective and safe can potentially be translated for clinical use. We report here a 27-amino acid peptide sequence mimicking the viral capsid protein, termed pepMAX, capable of co-assembling with mRNA into 100-150 nm nanostructures for efficient transfection of multiple cell lines. The mRNA loading and N/P ratio have been systematically optimized for each cell line. In HeLa, HEK293, and SKNMC, the transfection attained (>80%) is comparable with that of commercially available vectors Lipofectamine MessengerMAXTM (LipoMMAX). Confocal microscopy reveals that pepMAX efficiently delivers mRNA into the cytosol and induces efficient protein production. The pepMAX/mRNA co-assemblies retain their transfection efficiency after storage up to one week at room temperature in lyophilized form.

Effect of the underlying malignancy on critically ill septic patient's outcome.

BACKGROUND: Sepsis is an important cause of mortality and morbidity among critically ill patients with underlying malignancy. METHODS: Patients with sepsis admitted to the intensive care unit (ICU) of the Pamela Youde Nethersole Eastern Hospital from January 1, 2010 to April 30, 2019 were recruited. Demographics, laboratory parameter, and outcome were analyzed. Those with underlying malignancy were matched with those without malignancy based on their severity of organ failure (defined by the sequential organ failure assessment [SOFA] score) and septic source. RESULTS: Two hundred sixty-three patients with underlying active malignancy were matched with 259 patients without malignancy. Those with malignancy had higher APACHE IV score (89 vs. 83), lower albumin (22.1 vs. 24.4), neutrophil count (6.0 vs. 9.3), hemoglobin (8.0 vs. 9.8), platelet count (113 vs. 133), less use of mechanical ventilation (35.7% vs. 45.9%), renal replacement therapy (22.1% vs. 28.2%) and vasopressor (66.2% vs. 74.9%), higher 30-day (34.2% vs. 24.3%) ICU (22.4% vs. 18.9%), and 1-year (62.4% vs. 36.7%) mortality compared with those without malignancy. A higher APACHE IV score and pulmonary sepsis were predictors of 30-day mortality by Cox regression analysis. CONCLUSION: Disease severity and pulmonary sepsis, but not underlying malignancy, predicted short-term mortality among critically ill septic patients.

CD90 Marks a Mesenchymal Program in Human Thymic Epithelial Cells In Vitro and In Vivo.

Thymic epithelium is critical for the structural integrity of the thymus and for T cell development. Within the fully formed thymus, large numbers of hematopoietic cells shape the thymic epithelium into a scaffold-like structure which bears little similarity to classical epithelial layers, such as those observed in the skin, intestine or pancreas. Here, we show that human thymic epithelial cells (TECs) possess an epithelial identity that also incorporates the expression of mesenchymal cell associated genes, whose expression levels vary between medullary and cortical TECs (m/cTECs). Using pluripotent stem cell (PSC) differentiation systems, we identified a unique population of cells that co-expressed the master TEC transcription factor FOXN1, as well as the epithelial associated marker EPCAM and the mesenchymal associated gene CD90. Using the same serum free culture conditions, we also observed co-expression of EPCAM and CD90 on cultured TECs derived from neonatal human thymus in vitro. Single cell RNA-sequencing revealed these cultured TECs possessed an immature mTEC phenotype and expressed epithelial and mesenchymal associated genes, such as EPCAM, CLDN4, CD90 and COL1A1. Importantly, flow cytometry and single cell RNA-sequencing analysis further confirmed the presence of an EPCAM+CD90+ population in the CD45- fraction of neonatal human thymic stromal cells in vivo. Using the human thymus cell atlas, we found that cTECs displayed more pronounced mesenchymal characteristics than mTECs during embryonic development. Collectively, these results suggest human TECs possess a hybrid gene expression program comprising both epithelial and mesenchymal elements, and provide a basis for the further exploration of thymus development from primary tissues and from the in vitro differentiation of PSCs.

Adult mouse fibroblasts retain organ-specific transcriptomic identity.

Organ fibroblasts are essential components of homeostatic and diseased tissues. They participate in sculpting the extracellular matrix, sensing the microenvironment, and communicating with other resident cells. Recent studies have revealed transcriptomic heterogeneity among fibroblasts within and between organs. To dissect the basis of interorgan heterogeneity, we compare the gene expression of murine fibroblasts from different tissues (tail, skin, lung, liver, heart, kidney, and gonads) and show that they display distinct positional and organ-specific transcriptome signatures that reflect their embryonic origins. We demonstrate that expression of genes typically attributed to the surrounding parenchyma by fibroblasts is established in embryonic development and largely maintained in culture, bioengineered tissues and ectopic transplants. Targeted knockdown of key organ-specific transcription factors affects fibroblast functions, in particular genes involved in the modulation of fibrosis and inflammation. In conclusion, our data reveal that adult fibroblasts maintain an embryonic gene expression signature inherited from their organ of origin, thereby increasing our understanding of adult fibroblast heterogeneity. The knowledge of this tissue-specific gene signature may assist in targeting fibrotic diseases in a more precise, organ-specific manner.

Efficacy and Safety of Brigatinib Compared With Crizotinib in Asian vs. Non-Asian Patients With Locally Advanced or Metastatic ALK-Inhibitor-Naive ALK+ Non-Small Cell Lung Cancer: Final Results From the Phase III ALTA-1L Study.

BACKGROUND: Brigatinib is a next-generation anaplastic lymphoma kinase (ALK) inhibitor with demonstrated efficacy in locally advanced and metastatic non-small cell lung cancer (NSCLC) in crizotinib-refractory and ALK inhibitor-naive settings. This analysis assessed brigatinib in Asian vs. non-Asian patients from the first-line ALTA-1L trial. PATIENTS AND METHODS: This was a subgroup analysis from the phase III ALTA-1L trial of brigatinib vs. crizotinib in ALK inhibitor-naive ALK+ NSCLC. The primary endpoint was progression-free survival (PFS) as assessed by blinded independent review committee (BIRC). Secondary endpoints included confirmed objective response rate (ORR) and overall survival (OS) in the overall population and BIRC-assessed intracranial ORR and PFS in patients with brain metastases. RESULTS: Of the 275 randomized patients, 108 were Asian. Brigatinib showed consistent superiority in BIRC-assessed PFS vs. crizotinib in Asian (hazard ratio [HR]: 0.35 [95% CI: 0.20-0.59]; log-rank P = .0001; median 24.0 vs. 11.1 months) and non-Asian (HR: 0.56 [95% CI: 0.38-0.84]; log-rank P = .0041; median 24.7 vs. 9.4 months) patients. Results were consistent with investigator-assessed PFS and BIRC-assessed intracranial PFS. Brigatinib was well tolerated. Toxicity profiles and dose modification rates were similar between Asian and non-Asian patients. CONCLUSION: Efficacy with brigatinib was consistently better than with crizotinib in Asian and non-Asian patients with locally advanced or metastatic ALK inhibitor-naive ALK-+ NSCLC. There were no clinically notable differences in overall safety in Asian vs. non-Asian patients.

A platform for oncogenomic reporting and interpretation.

Manual interpretation of variants remains rate limiting in precision oncology. The increasing scale and complexity of molecular data generated from comprehensive sequencing of cancer samples requires advanced interpretative platforms as precision oncology expands beyond individual patients to entire populations. To address this unmet need, we introduce a Platform for Oncogenomic Reporting and Interpretation (PORI), comprising an analytic framework that facilitates the interpretation and reporting of somatic variants in cancer. PORI integrates reporting and graph knowledge base tools combined with support for manual curation at the reporting stage. PORI represents an open-source platform alternative to commercial reporting solutions suitable for comprehensive genomic data sets in precision oncology. We demonstrate the utility of PORI by matching 9,961 pan-cancer genome atlas tumours to the graph knowledge base, calculating therapeutically informative alterations, and making available reports describing select individual samples.

ATOM: A phase II study to assess efficacy of preemptive local ablative therapy to residual oligometastases of NSCLC after EGFR TKI.

OBJECTIVES: NSCLC patients harboring EGFR mutation invariably developed resistance to EGFR TKI. We postulated that oligoresidual disease (ORD) after initial TKI might harbor resistant clones. This study aimed to test if preemptive local ablative therapy (LAT) can improve progression free survival (PFS) or not compared to historic data. MATERIALS AND METHODS: Patients indicated for EGFR TKI who possessed ORD (≤ 4 PET-avid lesions) after an initial 3-month TKI therapy were enrolled. After screening PET-CT, eligible patients with PET-avid ORDs were treated by LAT, either by stereotactic ablative radiotherapy (SABR) or surgery per clinicians' discretion. TKI was continued after LAT until it was considered ineffective. PET-CT was repeated on the 3rd and 12th month post-LAT (or at progression) apart from regular imaging. Further LAT was allowed in oligoprogressive disease. Primary endpoint was PFS rate at one-year from enrollment. Overall survival (OS), PFS and treatment safety were secondary endpoints. A post hoc comparison with screen failure cohort was performed. RESULTS: Eighteen patients were enrolled from 2014-17. Recruitment was stopped before the planned number (34) due to slow accrual. Two were excluded due to consent withdrawal and significant protocol violation. Median follow up was 39.1 months. Among the 16 analyzed patients, the one-year PFS rate (i.e. 15 month post TKI) was 68.8 %. Median OS was 43.3 months. All LAT were done by SABR, and none experienced ≥ grade 3 SABR related toxicities. Compared with screen failure cohort (n = 48), pre-emptive LAT effectively reduced risk of progression (HR 0.41, p = 0.0097). CONCLUSION: Preemptive LAT in ORD appeared to be safe and feasible. The 1-year PFS rate was encouraging. However, potential biases and the limitations of the study should not be overlooked. Further randomized studies are warranted.

Attitudes, knowledge, and actions with regard to organ donation among Hong Kong medical students.

OBJECTIVE: To study attitudes, knowledge, and actions of local medical students with regard to organ donation and self-perceived confidence and competence in approaching potential organ donors. DESIGN: Cross-sectional questionnaire survey. SETTING: Faculty of Medicine, The University of Hong Kong, Hong Kong. PARTICIPANTS: Medical students, years 1-5. MAIN OUTCOME MEASURES: Knowledge on various aspects of organ donation was assessed, and students' self-evaluated competence and confidence about counselling for organ donation was evaluated. Factors influencing attitudes and actions were determined. RESULTS: The response rate was 94% (655/694). A majority (85%) had a 'positive' attitude, but only a small proportion (23%) had signed the organ donation card. Inconvenience and lack of knowledge about organ donor registration, and concerns about premature termination of medical treatment accounted for such discrepancies. Socio-cultural factors such as the traditional Chinese belief in preservation of an intact body after death, unease discussing death-related issues, and family objections to organ donation were significantly associated with a 'negative' attitude. Knowledge and action increased with medical education yet only a small proportion of medical students felt competent and confident in counselling patients on organ donation. CONCLUSIONS: The medical curriculum should increase medical students' awareness of the organ shortage problem. The donor registration system should be made more convenient and public education is recommended to correct misconceptions.

T790M mutant copy number quantified via ddPCR predicts outcome after osimertinib treatment in lung cancer.

Osimertinib prolongs progression-free survival (PFS) in patients with metastatic, epidermal growth factor receptor (EGFR) T790M-mutated, non-small cell lung cancer (NSCLC) after failure of EGFR tyrosine kinase inhibitor (TKI) therapy. We investigated the utility of T790M mutant copy number quantification in a plasma cell-free DNA (cfDNA) assay for predicting clinical outcomes of osimertinib treatment. We retrospectively examined 161 patients who underwent plasma EGFR testing using a digital droplet polymerase chain reaction (ddPCR) technique after EGFR-TKI failure. Of the 74 (46%) patients with detectable T790M mutations in plasma, 55 received osimertinib treatment. Patients who achieved partial response had a higher plasma mutant copy levels than those with progressive disease. Patients who achieved stable disease also tended to have higher plasma mutant copy levels than those with progressive disease. High mutant copy number (≥ 105 per mL of plasma) was associated with shorter PFS (median: 5.5 months vs. not reached) and overall survival (median: 9.1 months vs. NR). Quantitative measurements of T790M mutant copy number in plasma cfDNA by ddPCR thus predicted treatment response and survival outcomes after osimertinib in NSCLC patients resistant to EGFR TKI.

Targeted next-generation sequencing reveals recurrence-associated genomic alterations in early-stage non-small cell lung cancer.

PURPOSE: The identification of genomic alterations related to recurrence in early-stage non-small cell lung cancer (NSCLC) patients may help better stratify high-risk individuals and guide treatment strategies. This study aimed to identify the molecular biomarkers of recurrence in early-stage NSCLC. RESULTS: Of the 42 tumors evaluable for genomic alterations, TP53 and EGFR were the most frequent alterations with population frequency 52.4% and 50.0%, respectively. Fusion genes were detected in four patients, which had lower mutational burden and relatively better genomic stability. EGFR mutation and fusion gene were mutually exclusive in this study. CDKN2A, FAS, SUFU and SMARCA4 genomic alterations were only observed in the relapsed patients. Increased copy number alteration index was observed in early relapsed patients. Among these genomic alterations, early-stage NSCLCs harboring CDKN2A, FAS, SUFU and SMARCA4 genomic alterations were found to be significantly associated with recurrence. Some of these new findings were validated using The Cancer Genome Atlas (TCGA) dataset. CONCLUSIONS: The genomic alterations of CDKN2A, FAS, SUFU and SMARCA4 in early-stage NSCLC are found to be associated with recurrence, but confirmation in a larger independent cohort is required to define the clinical impact. MATERIALS AND METHODS: Paired primary tumor and normal lung tissue samples were collected for targeted next-generation sequencing analysis. A panel targets exons for 440 genes was used to assess the mutational and copy number status of selected genes in three clinically relevant groups of stage I/II NSCLC patients: 1) Early relapse; 2) Late relapse; and 3) No relapse.