Highlight of 2023: Unlocking the therapeutic potential of natural killer cells-advances in adaptive functions, cellular engineering and immunotherapy.

Natural killer (NK) cells possess potent cytotoxicity against infected and cancerous cells and hold promise in the development of new immunotherapies. This article for the Highlights of 2023 Series focuses on current advances in NK cell biology in cancerous and infectious settings and highlights opportunities for therapeutic interventions, including engineered NK cell therapies and advancements in feeder cell technologies.

Exploring NK cell receptor dynamics in paediatric leukaemias: implications for immunotherapy and prognosis.

Objectives: Immunotherapies targeting natural killer (NK) cell receptors have shown promise against leukaemia. Unfortunately, cancer immunosuppressive mechanisms that alter NK cell phenotype prevent such approaches from being successful. The study utilises advanced cytometry to examine how cancer immunosuppressive pathways affect NK cell phenotypic changes in clinical samples. Methods: In this study, we conducted a high-dimensional examination of the cell surface expression of 16 NK cell receptors in paediatric patients with acute myeloid leukaemia and acute lymphoblastic leukaemia, as well as in samples of non-age matched adult peripheral blood (APB) and umbilical cord blood (UCB). An unsupervised analysis was carried out in order to identify NK cell populations present in paediatric leukaemias. Results: We observed that leukaemia NK cells clustered together with UCB NK cells and expressed relatively higher levels of the NKG2A receptor compared to APB NK cells. In addition, CD56dimCD16+CD57- NK cells lacking NKG2A expression were mainly absent in paediatric leukaemia patients. However, CD56br NK cell populations expressing high levels of NKG2A were highly represented in paediatric leukaemia patients. NKG2A expression on leukaemia NK cells was found to be positively correlated with the expression of its ligand, suggesting that the NKG2A-HLA-E interaction may play a role in modifying NK cell responses to leukaemia cells. Conclusion: We provide an in-depth analysis of NK cell populations in paediatric leukaemia patients. These results support the development of immunotherapies targeting immunosuppressive receptors, such as NKG2A, to enhance innate immunity against paediatric leukaemia.

Long-term Insights: Histopathological Assessment in Polyurethane Implant Capsules up to 24 Years.

BACKGROUND: Polyurethane (PU)-coated breast implants are known for their strong integration into breast tissue and the formation of capsules around them. However, capsular contracture can pose both aesthetic and clinical challenges. OBJECTIVES: To analyze the biological and morphological characteristics of the capsular tissue surrounding PU-coated implants, irrespective of their contracture status, and to assess their potential suitability as a flap in revision breast surgery for capsular contracture. METHODS: A total of 23 tissue samples were harvested from the capsules surrounding PU-coated breast implants in 12 female patients during replacement or revision surgery. We evaluated collagen abundance, cellular and vascular density, inflammation, collagen band types and alignment, synovial metaplasia, capsule thickness, and the expression of inflammatory biomarkers and myofibroblasts using immunohistochemical techniques. Scanning electron microscopy was used to assess implant surface characteristics over time. RESULTS: We found a significant association of capsule contraction with longer implantation durations and greater implant surface roughness (p = 0.018 and p = 0.033, respectively). Synovial metaplasia was significantly more frequent in noncontracted capsules (p = 0.0049). Both capsule types consisted of paucicellular, type I collagen-rich compact fibrous tissue with low vascularization. There was a marked reduction in inflammatory cells within the foreign body granuloma. The expression of inflammatory biomarkers in the capsular tissue was negligible. CONCLUSIONS: Given the reduced levels of inflammatory and vascular components within the dense, fibrous capsular tissue, we consider them to be viable alternatives for use as capsular flaps in revision surgery. This strategy has the potential to mimic the reconstruction achieved with acellular dermal matrix.

Whole transcriptome profiling of placental pathobiology in SARS-CoV-2 pregnancies identifies placental dysfunction signatures.

Objectives: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus infection in pregnancy is associated with higher incidence of placental dysfunction, referred to by a few studies as a 'preeclampsia-like syndrome'. However, the mechanisms underpinning SARS-CoV-2-induced placental malfunction are still unclear. Here, we investigated whether the transcriptional architecture of the placenta is altered in response to SARS-CoV-2 infection. Methods: We utilised whole-transcriptome, digital spatial profiling, to examine gene expression patterns in placental tissues from participants who contracted SARS-CoV-2 in the third trimester of their pregnancy (n = 7) and those collected prior to the start of the coronavirus disease 2019 (COVID-19) pandemic (n = 9). Results: Through comprehensive spatial transcriptomic analyses of the trophoblast and villous core stromal cell subpopulations in the placenta, we identified SARS-CoV-2 to promote signatures associated with hypoxia and placental dysfunction. Notably, genes associated with vasodilation (NOS3), oxidative stress (GDF15, CRH) and preeclampsia (FLT1, EGFR, KISS1, PAPPA2) were enriched with SARS-CoV-2. Pathways related to increased nutrient uptake, vascular tension, hypertension and inflammation were also enriched in SARS-CoV-2 samples compared to uninfected controls. Conclusions: Our findings demonstrate the utility of spatially resolved transcriptomic analysis in defining the underlying pathogenic mechanisms of SARS-CoV-2 in pregnancy, particularly its role in placental dysfunction. Furthermore, this study highlights the significance of digital spatial profiling in mapping the intricate crosstalk between trophoblasts and villous core stromal cells, thus shedding light on pathways associated with placental dysfunction in pregnancies with SARS-CoV-2 infection.

In situ single-cell profiling sheds light on IFI27 localisation during SARS-CoV-2 infection.

The utilization of single-cell resolved spatial transcriptomics to delineate immune responses during SARS-CoV-2 infection was able to identify M1 macrophages to have elevated expression of IFI27 in areas of infection.

Leveraging spatial omics for the development of precision sarcoma treatments.

Sarcomas are rare and heterogeneous cancers that arise from bone or soft tissue, and are the second most prevalent solid cancer in children and adolescents. Owing to the complex nature of pediatric sarcomas, the development of therapeutics for pediatric sarcoma has seen little progress in the past decades. Existing treatments are largely limited to chemotherapy, radiation, and surgery. Limited knowledge of the sarcoma tumor microenvironment (TME) and of well-defined target antigens in the different subtypes necessitates an alternative investigative approach to improve treatments. Recent advances in spatial omics technologies have enabled a more comprehensive study of the TME in multiple cancers. In this opinion article we discuss advances in our understanding of the TME of some cancers enabled by spatial omics technologies, and we explore how these technologies might advance the development of precision treatments for sarcoma, especially pediatric sarcoma.

IKAROS and AIOLOS directly regulate AP-1 transcriptional complexes and are essential for NK cell development.

Ikaros transcription factors are essential for adaptive lymphocyte function, yet their role in innate lymphopoiesis is unknown. Using conditional genetic inactivation, we show that Ikzf1/Ikaros is essential for normal natural killer (NK) cell lymphopoiesis and IKZF1 directly represses Cish, a negative regulator of interleukin-15 receptor resulting in impaired interleukin-15 receptor signaling. Both Bcl2l11 and BIM levels, and intrinsic apoptosis were increased in Ikzf1-null NK cells, which in part accounts for NK lymphopenia as both were restored to normal levels when Ikzf1 and Bcl2l11 were co-deleted. Ikzf1-null NK cells presented extensive transcriptional alterations with reduced AP-1 transcriptional complex expression and increased expression of Ikzf2/Helios and Ikzf3/Aiolos. IKZF1 and IKZF3 directly bound AP-1 family members and deletion of both Ikzf1 and Ikzf3 in NK cells resulted in further reductions in Jun/Fos expression and complete loss of peripheral NK cells. Collectively, we show that Ikaros family members are important regulators of apoptosis, cytokine responsiveness and AP-1 transcriptional activity.

Development of Physiologically Relevant Skin Organoids from Human Induced Pluripotent Stem Cells.

The development of skin organs for studying developmental pathways, modeling diseases, or regenerative medicine purposes is a major endeavor in the field. Human induced pluripotent stem cells (hiPSCs) are successfully used to derive skin cells, but the field is still far from meeting the goal of creating skin containing appendages, such as hair follicles and sweat glands. Here, the goal is to generate skin organoids (SKOs) from human skin fibroblast or placental CD34+ cell-derived hiPSCs. With all three hiPSC lines, complex SKOs with stratified skin layers and pigmented hair follicles are generated with different efficacies. In addition, the hiPSC-derived SKOs develop sebaceous glands, touch-receptive Merkel cells, and more importantly eccrine sweat glands. Together, physiologically relevant skin organoids are developed by direct induction of embryoid body formation, along with simultaneous inactivation of transforming growth factor beta signaling, activation of fibroblast growth factor signaling, and inhibition of bone morphogenetic protein signaling pathways. The skin organoids created in this study can be used as valuable platforms for further research into human skin development, disease modeling, or reconstructive surgeries.

Molecular mechanisms of tumour necrosis factor signalling via TNF receptor 1 and TNF receptor 2 in the tumour microenvironment.

Tumour necrosis factor (TNF) is a primary mediator of inflammatory processes by facilitating cell death, immune cell activation and triggering of inflammation. In the cancer context, research has revealed TNF as a multifaceted cytokine that can be both pro- or anti-tumorigenic depending on what context is observed. We explore the plethora of ways that TNF and its receptors manipulate the functional and phenotypic characteristics in the tumour microenvironment (TME) on both tumour cells and immune cells, promoting either tumour elimination or progression. Here, we discuss the latest cutting-edge TNF-focused biologics currently in clinical translation that modifies the TME to derive greater immune responses and therapeutic outcomes, and further give perspectives on the future of targeting TNF in the context of cancer by emerging technological approaches.

Examining the haemodynamic repercussions of ventilator hyperinflation in elderly patients: An explanatory study.

This study assessed the cardiovascular repercussions of two VHI (ventilation hyperinflation) protocols using the volume-controlled mode, one with an inspiratory pause (VHI-P) and the other without an inspiratory pause (VHI-NP), in mechanically ventilated elderly patients. The patients underwent both VHI protocols in a randomized order, and impedance cardiography was used to record cardiovascular variables. During VHI-P, the diastolic blood pressure was lower than during VHI-NP (Δ = 10%; p = 0.009). VHI-NP and VHI-P demonstrated a decrease in cardiac output (CO) during the first and third sets compared to baseline (p < 0.05; ES=0.23 and 0.29, respectively). Arterial oxygen delivery decreased simultaneously with CO compared to baseline values (p < 0.05; ES=0.22 and 0.23, respectively). Five minutes after the intervention, the systolic time ratio values were lower for VHI-P than VHI-NP (Δ = 10%; p = 0.01). Left ventricular ejection time values were consistently lower in VHI-NP compared to VHI-P (Δ = 2%; p = 0.02). In conclusion, our study shows that VHI in volume-controlled mode induces hemodynamic changes in mechanically ventilated elderly patients, albeit with a small effect size and within the normal range.

A robust platform for integrative spatial multi-omics analysis to map immune responses to SARS-CoV-2 infection in lung tissues.

The SARS-CoV-2 (COVID-19) virus has caused a devastating global pandemic of respiratory illness. To understand viral pathogenesis, methods are available for studying dissociated cells in blood, nasal samples, bronchoalveolar lavage fluid and similar, but a robust platform for deep tissue characterization of molecular and cellular responses to virus infection in the lungs is still lacking. We developed an innovative spatial multi-omics platform to investigate COVID-19-infected lung tissues. Five tissue-profiling technologies were combined by a novel computational mapping methodology to comprehensively characterize and compare the transcriptome and targeted proteome of virus infected and uninfected tissues. By integrating spatial transcriptomics data (Visium, GeoMx and RNAScope) and proteomics data (CODEX and PhenoImager HT) at different cellular resolutions across lung tissues, we found strong evidence for macrophage infiltration and defined the broader microenvironment surrounding these cells. By comparing infected and uninfected samples, we found an increase in cytokine signalling and interferon responses at different sites in the lung and showed spatial heterogeneity in the expression level of these pathways. These data demonstrate that integrative spatial multi-omics platforms can be broadly applied to gain a deeper understanding of viral effects on cellular environments at the site of infection and to increase our understanding of the impact of SARS-CoV-2 on the lungs.

Copper chelation suppresses epithelial-mesenchymal transition by inhibition of canonical and non-canonical TGF-ß signaling pathways in cancer.

BACKGROUND: Metastatic cancer cells exploit Epithelial-mesenchymal-transition (EMT) to enhance their migration, invasion, and resistance to treatments. Recent studies highlight that elevated levels of copper are implicated in cancer progression and metastasis. Clinical trials using copper chelators are associated with improved patient survival; however, the molecular mechanisms by which copper depletion inhibits tumor progression and metastasis are poorly understood. This remains a major hurdle to the clinical translation of copper chelators. Here, we propose that copper chelation inhibits metastasis by reducing TGF-ß levels and EMT signaling. Given that many drugs targeting TGF-ß have failed in clinical trials, partly because of severe side effects arising in patients, we hypothesized that copper chelation therapy might be a less toxic alternative to target the TGF-ß/EMT axis. RESULTS: Our cytokine array and RNA-seq data suggested a link between copper homeostasis, TGF-ß and EMT process. To validate this hypothesis, we performed single-cell imaging, protein assays, and in vivo studies. Here, we used the copper chelating agent TEPA to block copper trafficking. Our in vivo study showed a reduction of TGF-ß levels and metastasis to the lung in the TNBC mouse model. Mechanistically, TEPA significantly downregulated canonical (TGF-ß/SMAD2&3) and non-canonical (TGF-ß/PI3K/AKT, TGF-ß/RAS/RAF/MEK/ERK, and TGF-ß/WNT/ß-catenin) TGF-ß signaling pathways. Additionally, EMT markers of MMP-9, MMP-14, Vimentin, ß-catenin, ZEB1, and p-SMAD2 were downregulated, and EMT transcription factors of SNAI1, ZEB1, and p-SMAD2 accumulated in the cytoplasm after treatment. CONCLUSIONS: Our study suggests that copper chelation therapy represents a potentially effective therapeutic approach for targeting TGF-ß and inhibiting EMT in a diverse range of cancers.

Chest physiotherapy techniques administered by certified specialists to hospitalized patients with COVID-19 in Brazil: A look towards future practice.

BACKGROUND: Chest physiotherapy for hospitalized patients with COVID-19 has been poorly reported. Although recommendations were published to guide physiotherapists, practice might have differed depending on education and training. OBJECTIVE: To analyze the differences in chest physiotherapy applied for hospitalized patients with COVID-19 between certified specialists and non-certified specialists. METHODS: An online questionnaire survey was developed for physiotherapists involved in the management of hospitalized patients with COVID-19. The questionnaire inquired about professional information and characteristics of physiotherapy practice. RESULTS: There were 485 respondents, yielding a completion rate of 76%. Of these, 61 were certified specialists and 424 non-certified specialists. The certified specialists were older, had more years of professional experience, were more qualified, and had better job conditions. For mechanically ventilated patients, the certified specialists used the ventilator hyperinflation maneuver more frequently (50.4% vs 35.1%, p = 0.005), and the hard/brief expiratory rib cage compression (ERCC) (26.9% vs 48.3%, p = 0.016), soft/long ERCC (25.2% vs 39.1%, p = 0.047), and manual chest compression-decompression (MCCD) maneuver (22.4% vs 35.6%, p = 0.001) less often. For spontaneously breathing patients, the certified specialists used the active cycle of breathing technique (30.8% vs 67.1%, p<0.001), autogenic drainage (7.7% vs 20.7%, p = 0.017), and MCCD maneuver (23.1% vs 41.4%, p = 0.018) less frequently. CONCLUSIONS: Certified specialists with higher levels of expertise seem to prefer the use of chest physiotherapy techniques that are applied with the mechanical ventilator over manual techniques. Furthermore, they use techniques that could potentially increase the work of breathing less frequently, mitigating the risk of exacerbating respiratory conditions in patients with COVID-19.

Killer cell immunoglobulin-like receptor (KIR) genes and their HLA ligands in a Brazilian population.

Killer cell immunoglobulin-like receptors (KIR) exhibit extensive diversity, giving rise to different KIR profiles in populations worldwide. This study aimed to investigate the distribution of KIR genes and HLA ligands in a population from Campinas, southeastern Brazil (n = 292), and to compare their results with other populations. A comprehensive analysis of population-specific genes, genotype, and haplotype frequencies of KIR may facilitate a better understanding of their evolution and role in immunity. The genotyping of 16 KIR genes and HLA class I alleles was performed by the reverse sequence-specific oligonucleotide methodology using the Luminex platform (One Lambda, Inc., Canoga Park, CA). The framework genes were present in all individuals, with the most common non-framework KIR genes detected being KIR2DP1(96.6%), KIR2DL1(95.5%), KIR3DL1(94.5%), KIR2DS4(93.8%) and KIR2DL3(87.3%). KIR2DS1, KIR2DS3, KIR2DS5, and KIR3DS1 presented frequencies below 40%. KIR2DL2, KIR2DL5, and KIR2DS2 showed intermediate frequencies (between53% and 58%). The activating gene KIR2DS5 was the least common in this population (30.8%). Forty-five KIR profiles were found with the commonest being the homozygous A haplotype (27.4%). The distribution of KIR genes in the Brazilian population is similar to Caucasian European and Euro-descendant populations.

Post-COVID-19 functional status scale: Cross-cultural adaptation and measurement properties of the Brazilian Portuguese version.

BACKGROUND: The Post-COVID-19 Functional Status (PCFS) scale was created to assess the functional status of patients after hospital discharge due to COVID-19. OBJECTIVE: To perform cross-cultural adaptation of the PCFS Scale and Manual into Brazilian Portuguese and evaluate its measurement properties in patients post-COVID-19. METHODS: For the cross-cultural adaptation, independent translations and back-translations were performed. This was followed by a pre-test, with analysis of the Content Validity Index (CVI), and preparation of the final version, after evaluating the measurement properties. Spearman's correlation between the PCFS and the WHO Disability Classification Scheme (WHODAS 2.0) was used for convergent validity. Weighted Kappa (wκ) was used for test-retest and interobserver reliability for PCFS scores and Kappa (κ) for PCFS items. Internal consistency was assessed using Cronbach's alpha. Only patients with post-discharge COVID-19 were evaluated through video-conferencing platforms. RESULTS: The CVI was 0.75-0.83 for comprehension and 0.83-0.84 for the language of the self-administered questionnaire and the structured interview version. For measurement properties, 63 patients were evaluated, 68% male, 51.50 (12.60) years, 12.28 (7.62) days of hospitalization. For the convergent validity, a strong correlation was found (r = 0.73; p<0.01). The test-retest (wκ=0.54) and interobserver (wκ=0.43) reliability was moderate and the item-by-item analyzes ranged from fair to substantial (κ=0.25-0.66) and weak to substantial (κ=0.07-0.79). Internal consistency was excellent (0.85). CONCLUSION: The final PCFS in Brazilian Portuguese showed adequate content validity, reliability, internal consistency, and convergent validity for the functional assessment of patients after hospital discharge due to COVID-19.

Oncogenic drivers dictate immune control of acute myeloid leukemia.

Acute myeloid leukemia (AML) is a genetically heterogeneous, aggressive hematological malignancy induced by distinct oncogenic driver mutations. The effect of specific AML oncogenes on immune activation or suppression is unclear. Here, we examine immune responses in genetically distinct models of AML and demonstrate that specific AML oncogenes dictate immunogenicity, the quality of immune response and immune escape through immunoediting. Specifically, expression of NrasG12D alone is sufficient to drive a potent anti-leukemia response through increased MHC Class II expression that can be overcome with increased expression of Myc. These data have important implications for the design and implementation of personalized immunotherapies for patients with AML.

Gait speed, muscle strength, and functional status predict 30-day unplanned hospital readmission of critical care survivors.

BACKGROUND AND PURPOSE: Despite intense efforts, predicting hospital readmission risks remains an imprecise task. Growing evidence suggests that unmeasured patient-related factors, such as functional impairment, seem to be strongly associated with acute readmission and have yet to be extensively explored. We hypothesized that gait speed, hand grip strength, and the Functional independence measure (FIM) might be associated with acute rehospitalization rates after an ICU stay. METHODS: In our study, we assessed gait speed using a 10-m walk test. Muscle strength was determined by a hydraulic handgrip dynamometer and functional status through the FIM. Our primary outcome was the cumulative incidence of the first unplanned early rehospitalization (occurring within 30 days of hospital discharge) for the entire cohort, and a Receiver Operator Characteristic (ROC) analysis was used to determine the accuracy of gait speed, handgrip strength, and FIM domains in predicting hospital readmission. RESULTS: ROC analysis indicated that the gait speed (AUC 0.96 95% CI 0.93 to 0.99), FIM score (AUC 0.96 95% CI 0.94 to 0.99) and handgrip strength (0.85 95% CI 0.76 to 0.94) were considered accurate predictors of unplanned readmission in the population studied. Additionally, we found that each 0.1 m/s lower gait speed was associated with a 10% higher odd of unplanned readmissions. CONCLUSION: Hence, our results suggest gait speed, handgrip strength and functional status demonstrated high potential to contribute to the determination of 30-day unplanned hospital readmission prediction of critical care survivors.

Intramuscular Gluteoplasty: A Comparative Study between Different Incisional Access Routes.

BACKGROUND: Silicone implants have been used to improve volume and body contour in buttocks for almost 45 years. Although the intramuscular plane continues to be the standard, surgeons still diverge on the best incision technique: using a vertical incision, and thus without the preservation of the intergluteal groove, or preserving this area through a triangular dissection. The goal of this research study was to evaluate and compare these techniques of intramuscular augmentation gluteoplasty. METHODS: Two randomized groups were formed with 53 patients in each group. One of the groups underwent intramuscular gluteoplasty with a vertical incision in the intergluteal groove, and therefore without the preservation of said intergluteal groove (group A). In the other group, intramuscular gluteoplasty was performed using a triangular dissection, thus preserving the intergluteal groove (group B). The groups were compared in relation to the incidence of complications (ie, dehiscence, hematoma, seroma, and infection). RESULTS: A total of 7.5% of patients in group A presented dehiscence and 1.9% presented seroma. In group B, however, 28.3% of patients presented dehiscence and 7.5% presented seroma and dehiscence during the first 21 days after surgery. No patient had hematoma or infection in either group. CONCLUSION: In the comparison between the groups of patients, the technique with a vertical incision in the intergluteal groove showed a lower number of surgical wounds, dehiscences, and seromas when compared with the technique that preserves the intergluteal groove. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.