The T cell differentiation landscape is shaped by tumour mutations in lung cancer

Tumour mutational burden (TMB) predicts immunotherapy outcome in non-small cell lung cancer (NSCLC), consistent with immune recognition of tumour neoantigens. However, persistent antigen exposure is detrimental for T cell function. How TMB affects CD4 and CD8 T cell differentiation in untreated tumours and whether this affects patient outcomes is unknown. Here, we paired high-dimensional flow cytometry, exome, single-cell and bulk RNA sequencing from patients with resected, untreated NSCLC to examine these relationships. TMB was associated with compartment-wide T cell differentiation skewing, characterized by loss of TCF7-expressing progenitor-like CD4 T cells, and an increased abundance of dysfunctional CD8 and CD4 T cell subsets with strong phenotypic and transcriptional similarity to neoantigen-reactive CD8 T cells. A gene signature of redistribution from progenitor-like to dysfunctional states was associated with poor survival in lung and other cancer cohorts. Single-cell characterization of these populations informs potential strategies for therapeutic manipulation in NSCLC

Large-scale detection of antigen-specific T cells using peptide-MHC-I multimers labeled with DNA barcodes

Identification of the peptides recognized by individual T cells is important for understanding and treating immune-related diseases. Current cytometry-based approaches are limited to the simultaneous screening of 10–100 distinct T-cell specificities in one sample. Here we use peptide–major histocompatibility complex (MHC) multimers labeled with individual DNA barcodes to screen >1,000 peptide specificities in a single sample, and detect low-frequency CD8 T cells specific for virus- or cancer-restricted antigens. When analyzing T-cell recognition of shared melanoma antigens before and after adoptive cell therapy in melanoma patients, we observe a greater number of melanoma-specific T-cell populations compared with cytometry-based approaches. Furthermore, we detect neoepitope-specific T cells in tumor-infiltrating lymphocytes and peripheral blood from patients with non-small cell lung cancer. Barcode-labeled pMHC multimers enable the combination of functional T-cell analysis with large-scale epitope recognition profiling for the characterization of T-cell recognition in various diseases, including in small clinical samples

Clonal neoantigens elicit T cell immunoreactivity and sensitivity to immune checkpoint blockade

As tumors grow, they acquire mutations, some of which create neoantigens that influence the response of patients to immune checkpoint inhibitors. We explored the impact of neoantigen intratumor heterogeneity (ITH) on antitumor immunity. Through integrated analysis of ITH and neoantigen burden, we demonstrate a relationship between clonal neoantigen burden and overall survival in primary lung adenocarcinomas. CD8(+) tumor-infiltrating lymphocytes reactive to clonal neoantigens were identified in early-stage non–small cell lung cancer and expressed high levels of PD-1. Sensitivity to PD-1 and CTLA-4 blockade in patients with advanced NSCLC and melanoma was enhanced in tumors enriched for clonal neoantigens. T cells recognizing clonal neoantigens were detectable in patients with durable clinical benefit. Cytotoxic chemotherapy–induced subclonal neoantigens, contributing to an increased mutational load, were enriched in certain poor responders. These data suggest that neoantigen heterogeneity may influence immune surveillance and support therapeutic developments targeting clonal neoantigens

Normative values of eccentric hip abduction strength in novice runners:an equation adjusting for age and gender

PURPOSE: Low eccentric strength of the hip abductors, might increase the risk of patellofemoral pain syndrome and iliotibial band syndrome in runners. No normative values for maximal eccentric hip abduction strength have been established. Therefore the purpose of this study was to establish normative values of maximal eccentric hip abduction strength in novice runners. METHODS: Novice healthy runners (n = 831) were recruited through advertisements at a hospital and a university. Maximal eccentric hip abduction strength was measured with a hand–held dynamometer. The demographic variables associated with maximal eccentric hip abduction strength from a univariate analysis were included in a multivariate linear regression model. Based on the results from the regression model, a regression equation for normative hip abduction strength is presented. RESULTS: A significant difference in maximal eccentric hip abduction strength was found between males and females: 1.62 ± 0.38 Nm/kg (SD) for males versus 1.41 ± 0.33 Nm/kg (SD) for females (p < 0.001). Age was associated with maximal eccentric hip abduction strength: per one year increase in age a ‐0.0045 ± 0.0013 Nm/kg (SD) decrease in strength was found, p < 0.001. Normative values were identified using a regression equation adjusting for age and gender. Based on this, the equation to calculate normative values for relative eccentric hip abduction strength became: (1.600 + (age * ‐0.005) + (gender (1 = male / 0 = female) * 0.215) ± 1 or 2 * 0.354) Nm/kg. CONCLUSION: Normative values for maximal eccentric hip abduction strength in novice runners can be calculated by taking into account the differences in strength across genders and the decline in strength that occurs with increasing age. Age and gender were associated with maximal eccentric hip abduction strength in novice runners, and these variables should be taken into account when evaluating eccentric hip abduction strength in this group of athletes. LEVEL OF EVIDENCE: 2

No association between q-angle and foot posture with running-related injuries:A 10 week prospective follow-up study

BACKGROUND/PURPOSE: There is a paucity of knowledge on the association between different foot posture quantified by Foot Posture Index (FPI) and Quadriceps angle (Q-angle) with development of running-related injuries. Earlier studies investigating these associations did not include an objective measure of the amount of running performed. Therefore, the purpose of this study was to investigate if kilometers to running-related injury (RRI) differ among novice runners with different foot postures and Q-angles when running in a neutral running shoe. METHODS: A 10 week study was conducted including healthy, novice runners. At baseline foot posture was evaluated using the foot posture index (FPI) and the Q-angle was measured. Based on the FPI and Q-angle, right and left feet / knees of the runners were categorized into exposure groups. All participants received a Global Positioning System watch to allow them to quantify running volume and were instructed to run a minimum of two times per week in a conventional, neutral running shoe. The outcome was RRI. RESULTS: Fifty nine novice runners of mixed gender were included. Of these, 13 sustained a running-related injury. No significant difference in cumulative relative risk between persons with pronated feet and neutral feet was found after 125 km of running (Cumulative relative risk = 1.65 [0.65; 4.17], p = 0.29). Similarly, no difference was found between low and neutral Q-angle (Cumulative relative risk = 1.25 [0.49; 3.23], p = 0.63). CONCLUSION: Static foot posture as quantified by FPI and knee alignment as quantified by Q-angle do not seem to affect the risk of injury among novice runners taking up a running regimen wearing a conventional neutral running shoe. These results should be interpreted with caution due to a small sample size. LEVEL OF EVIDENCE: 2

The effect of speed on Achilles tendon forces and patellofemoral joint stresses in high‐performing endurance runners

Achilles tendinopathy and patellofemoral pain are common running injuries associated with increased Achilles tendon (AT) forces and patellofemoral joint (PFJ) stresses. This study examined AT forces and PFJ stresses at different running speeds in high performing endurance runners. Twenty runners ran overground at four running speeds (3.3, 3.9, 4.8 and 5.6m/s). AT forces and PFJ stresses were estimated from kinematic and kinetic data. Repeated measures ANOVA with partial eta squared effect sizes were conducted to assess differences between running speeds. Increased peak AT forces (19.5%; p<.001) and loading rates (57.3%; p<.001) from 3.3m/s to 5.6m/s were observed. Cumulative AT loading was greater in the faster speeds compared to the slower speeds. Faster running speeds resulted in increased peak plantar flexor moments, increased peak plantarflexion angles, and a more flexed knee and an anterior centre of pressure position at touchdown. Peak PFJ stress was lower in the slowest speed (3.3 m/s) compared to the faster running speeds (3.9‐5.6m/s; p=.005). PFJ stress loading rate significantly increased (43.6%; p<.001). Greater AT loading observed could be associated with strategies such as increased plantar flexor moments and altered lower body position at touchdown which are commonly employed to generate greater ground contact forces. Greater AT and PFJ loading rates were likely due to shorter ground contact times and therefore less time available to reach the peak. Running at faster speeds could increase the risk of developing Achilles tendinopathy and patellofemoral pain or limit recovery from these injuries without sufficient recovery

The T cell differentiation landscape is shaped by tumour mutations in lung cancer

Tumour mutational burden (TMB) predicts immunotherapy outcome in non-small cell lung cancer (NSCLC), consistent with immune recognition of tumour neoantigens. However, persistent antigen exposure is detrimental for T cell function. How TMB affects CD4 and CD8 T cell differentiation in untreated tumours, and whether this affects patient outcomes is unknown. Here we paired high-dimensional flow cytometry, exome, single-cell and bulk RNA sequencing from patients with resected, untreated NSCLC to examine these relationships. TMB was associated with compartment-wide T cell differentiation skewing, characterized by loss of TCF7-expressing progenitor-like CD4 T cells, and an increased abundance of dysfunctional CD8 and CD4 T cell subsets, with significant phenotypic and transcriptional similarity to neoantigen-reactive CD8 T cells. A gene signature of redistribution from progenitor-like to dysfunctional states associated with poor survival in lung and other cancer cohorts. Single-cell characterization of these populations informs potential strategies for therapeutic manipulation in NSCLC