Citations

Abstract Description Persistent exposure to antigens and immunosuppressive signals in tumors or chronic infections drives CD8+ T cell exhaustion (Tex), a programmed state of T cell dysfunction. While efforts have been made to combat Tex through immunotherapies, they often fail to induce lasting protective effects. Exhausted CD8+ T cells consist of various subsets with distinct transcriptional, functional, and metabolic features. Among these subsets, progenitor exhausted CD8+ T cells (Tprog) are important: they are metabolically quiescent, retain stemness capacity and respond better to checkpoint blockade therapy (e.g., anti-PD1). Here, we report that, in response to chronic viral infection (LCMV Clone 13), P2RX7 is crucial for the establishment of Tprog cells. P2RX7-KO CD8+ T cells had decreased numbers of Tprog cells. P2RX7-KO Tprog cells lose metabolic quiescence, displaying increased glycolytic function and loss of mitochondrial respiration dependence. Our meta-analyses of gene (scRNAseq) and protein (LegendScreen assay) expression suggest that P2RX7-KO Tprog cells undergo abnormal exhaustion differentiation paths, and express reduced levels of integrin beta-1 (ITGB1), a molecule associated with lymphoid residency of Tprog cells. Finally, we found that P2RX7 is crucial for exhausted CD8+ T cells to respond to anti-PD1 in vivo. These data open the possibility of using P2RX7 agonism to boost the efficacy of existing checkpoint blockade immunotherapies aimed to revitalize CD8+ T cell responses. Funding Sources NIH Grants K99/R00A139381 and R01A170649 Topic Categories Lymphocyte Differentiation and Peripheral Maintenance (LYM)

Abstract Description Immune responses to allergens vary depending on the route of sensitization, but the mechanisms behind these differences are not clear. Damage signals from the microenvironment dictate the immune response magnitude and may regulate route of sensitization differences. Extracellular ATP (eATP) is a danger signal released by inflamed tissues and sensed by immune cells via P2RX7. The role of P2RX7 in CD4+ Th2 cell responses to allergen is unclear, with past reports suggesting opposite effects of P2RX7 knockout (KO). Here, we tracked the role of P2RX7 on CD4+ T cell-mediated lung allergy in response to different routes of sensitization. Comparing Papain + Ovalbumin (OVA) intranasal versus subcutaneous sensitization, we found increased lung type 2 inflammation and lung CD4+CD69+GATA3+ T cells in response to the subcutaneous route, compared to intranasal route. P2RX7-KO led to decreased lung CD4+ Th2 cell responses and reduced inflammation in mice exposed to subcutaneous, but not intranasal sensitization. Subcutaneous OVA + Papain led to a stronger eosinophilic response, while both eosinophils and neutrophils were elicited by intranasal route. Our results indicate that sensing of eATP through P2RX7 exacerbate the intensity of subcutaneous allergen-induced Th2 responses. We are currently comparing the Th2 responses induced by subcutaneous versus intranasal allergen sensitization, and how P2RX7 oppositely regulate such responses. Funding Sources NIH K99/R00A139381 NIH R01A170649 Topic Categories Immediate Hypersensitivity, Asthma, and Allergic Responses (HYP)

Abstract Purpose: The role of tumor-infiltrating lymphocytes (TIL) remains unclear in hormone receptor (HR)–positive/HER2-negative breast cancer, particularly in young patients, whose immune microenvironment could be altered by age-related host and tumor differences. Experimental Design: Patients with stage I to III HR-positive/HER2-negative tumors were identified from a prospective cohort study of patients with breast cancer diagnosed at age ≤40 years. Multiplexed immunofluorescence and semiautomated quantitative software measured cytotoxic T, non–CD8 T, T regulatory, exhausted T, and PDL1+ cells in stroma and tumor. Univariate analyses assessed differences in clinicopathologic characteristics by high versus low immune infiltration, divided based on median. TIL subtypes were evaluated as a continuous variable per 10% increase in Cox regression analyses for invasive breast cancer–free survival, distant disease–free survival (DDFS), and overall survival, adjusted for clinicopathologic parameters. Results: Among 390 patients, high immune infiltration was associated with increasing age, Black race, grade 3 tumors, and metaplastic or micropapillary histologic subtypes. Over a median follow-up of 8 years, higher stromal and intratumoral non–CD8 T-cell infiltration, T regulatory–cell infiltration, and PDL1 expression were associated with improved invasive breast cancer–free survival. Higher intratumoral non–CD8 T-cell infiltration, T regulatory–cell infiltration, and PDL1 expression were associated with improved DDFS; higher stromal PDL1 expression was also associated with improved DDFS. Higher intratumoral cytotoxic T-cell infiltration and PDL1 expression were associated with improved overall survival. Conclusions: Characterization of immune subpopulations could help refine the prognostic value of TILs in young patients with HR-positive breast cancer, who may benefit from risk stratification for treatment individualization. See related commentary by Salgado and Kok, p. 2133

PURPOSE Given the extended survivorship of young adults with breast cancer, characterizing health care utilization and adherence to surveillance guidelines can inform gaps in care. PATIENTS AND METHODS Patients age 40 years and younger at diagnosis of stage 0-III breast cancer enrolled in a prospective cohort study completed a survey 7 years after diagnosis assessing receipt of care and surveillance. We evaluated factors associated with transition to a primary care provider (PCP) for cancer-related follow-up and adherence to mammography and bone density scans. RESULTS Among 660 women, 92% reported having a PCP, although for cancer-related follow-up, 57% saw only an oncology provider, 29% saw both a PCP and oncology provider. In the past 2 years, 68% reported getting a flu shot, 76% a pap test/pelvic examination, 56% cholesterol screening, and 42% (n = 232 endocrine therapy [ET] users) a bone density scan. Among women who had a unilateral mastectomy or lumpectomy (n = 356), 82% reported a mammogram in the past year. In multivariate analyses, those with stage 0 ( v I disease) were more likely to see a PCP for follow-up ( v PCP + oncology provider); ET users and those more concerned about recurrence were less likely. Patients with human epidermal growth factor receptor 2-positive (HER2) disease were more likely to adhere to mammography; those with a BRCA mutation and those with a unilateral mastectomy were less likely. Patients with a BRCA mutation and who had chemotherapy were more likely to report a bone density scan. CONCLUSION Although most have a PCP, over half of young survivors continue to see an oncology provider for follow-up in long-term survivorship. Mammography uptake was high; uptake of other health maintenance practices was lower. Identification of barriers/facilitators to receipt of guideline-concordant care may inform strategies to optimize survivorship.

Abstract The effectiveness of T cell–based immunotherapy depends on durable T-cell responses that can efficiently eliminate tumor cells. NKG7 was discovered three decades ago as a protein associated with lytic granules. However, only studies published over the past 5 years have contributed substantially to our understanding of NKG7 in T-cell biology. NKG7 has been recognized as an important T-cell functional marker in responses to immune checkpoint inhibitor therapy and in the prognosis of certain cancers. Besides its role in the generation, trafficking, and release of lytic granules, which is critical for efficient T-cell cytotoxicity against tumor cells, NKG7 has been identified as a key negative regulator of mTORC1 activity. By restraining mTORC1 activity, NKG7 promotes T-cell longevity and memory generation after infection. Importantly, NKG7 upregulation has demonstrated therapeutic potential in preclinical T-cell therapy for cancer. Collectively, NKG7 is emerging as a promising biomarker and therapeutic addition to T cell–based immunotherapies.

Importance Women diagnosed with breast cancer at a young age are felt to have a higher risk for locoregional recurrence (LRR) regardless of type of local therapy. Objective To assess the long-term incidence of isolated LRR by molecular subtype in a modern multicenter cohort of young women. Design, Setting, and Participants This cohort study, a multicenter prospective study named the Young Women’s Breast Cancer Study, enrolled 1302 women diagnosed with breast cancer at 40 years or younger from 2006 to 2016. Treatment information and incident LRR (ipsilateral breast/chest or lymph node recurrence) were self-reported on study surveys and confirmed with medical record review; molecular subtype was determined by record review. Analysis was reported from February 2023 to May 2025. Main Outcomes and Measures Cumulative incidence of isolated LRR was calculated using the Kaplan-Meier method; hazard ratios were estimated by Cox proportional hazards regression. Results The cohort included 1135 women with stage I through III breast cancer who had a median follow-up of 10.1 years (range, 0.4-16.3 years). The age at diagnosis was younger than 30 years for 145 patients (12.8%), 31 to 35 years for 318 patients (28.0%), and 36 to 40 years for 672 patients (59.2%). There were 59 isolated local recurrences (5.2%) and 4 isolated regional recurrences (0.4%). Among patients with local therapy and subtype data available (n = 1128), 366 (32%) had luminal A–like tumors; 240 (21%), luminal B–like tumors; 231 (20%) luminal ERBB2 positive (+)–like (formerly HER2 positive); 90 (8%) ERBB2 +-like; and 201 (18%) triple negative. A total of 346 women (30%) had breast-conserving therapy (BCT) (98% of whom had radiation), 296 (26%) unilateral mastectomy, and 487 (43%) bilateral mastectomy. Of women who had mastectomy, 425 (54%) had radiation. The cumulative incidence of LRR at 10.1 years by subtype was as follows: luminal A, 4.4% (range, 1.0%-6.9%); luminal B, 4.7% (range 1.8%-7.7%); luminal ERBB2 +, 6.1% (range, 3.1%-8.3%); ERBB2 +, 2.2% (range, 0%-6.3%); and triple negative, 6.5% (range, 4.2%-10.1%). The cumulative incidence of LRR by locoregional treatment type at 10.1 years was 6.7% after BCT (range, 4.3%-10.1%), 6.5% after mastectomy without radiation (range, 0%-7.7%), and 2.4% after mastectomy with radiation (range, 1%-4.2%). Although mastectomy with radiation was associated with the lowest risk of LRR on multivariable analysis, when examined within molecular subtype, there were no differences seen. Conclusions and Relevance In this contemporary cohort of women diagnosed with breast cancer at age 40 years or younger, risk of isolated LRR was relatively low (5.6%) at a median follow-up of 10.1 years, and significant differences were not seen by tumor subtype. Concerns for long-term risk of LRR should not influence surgical decision-making with young women, irrespective of molecular subtype.

Background: In the emergency setting, many diagnostic pathways incorporate change in high-sensitivity cardiac troponin (hs-cTn) concentrations (i.e., the delta) to classify patients as low-risk (rule-out) or high-risk (rule-in) for possible myocardial infarction (MI). However, the impact of analytical variation on the delta for correct classification is unknown, especially at concentrations below and around the 99th percentile. Our objective was to assess the impact of delta variation for correct risk classification across the European Society of Cardiology (ESC 0/1 h and 0/2 h), the High-STEACS, and the common change criteria (3C) pathways. Methods: A yearlong accuracy study for hs-cTnT was performed where laboratories across Canada tested three patient-based samples (level 1 target value = 6 ng/L, level 2 target value = 9 ng/L, level 3 target value = 12 ng/L) monthly across 41 different analyzers. The assigned low-delta between levels 1 and 2 was 3 ng/L (i.e., 9 − 6 = 3 ng/L) and the assigned high-delta between levels 1 and 3 was 6 ng/L (i.e., 12 − 6 = 6 ng/L). The low- and high-deltas for each analyzer were determined monthly from the measured values, with the difference calculated from the assigned deltas. The obtained deltas were then assessed via the different pathways on correct classification (i.e., percent correct with 95% confidence intervals, CI) and using non-parametric analyses. Results: The median (interquartile range) difference between the measured versus assigned low-delta (n = 436) and high-delta (n = 439) was −1 ng/L (−1 to 0). The correct classification differed among the pathways. The ESC 0/1 h pathway yielded the lowest percentage of correct classification at 35.3% (95% CI: 30.8 to 40.0) for the low-delta and 90.0% (95% CI: 86.8 to 92.6) for the high-delta. The 3C and ESC 0/2 h pathways yielded higher and equivalent estimates on correct classification: 95.2% (95% CI: 92.7 to 97.0) for the low-delta and 98.2% (95% CI: 96.4 to 99.2) for the high-delta. The High-STEACS pathway yielded 99.5% (95% CI: 98.4 to 99.9) of correct classifications for the high-delta but only 36.2% (95% CI: 31.7 to 40.9) for the low-delta. Conclusions: Analytical variation will impact risk classification for MI when using hs-cTn deltas alone per the pathways. The 3C and ESC 0/2 h pathways have <5% misclassification when using deltas for hs-cTnT in this dataset. Additional studies with different hs-cTnI assays at concentrations below and near the 99th percentile are warranted to confirm these findings.

The differentiation of naive CD8+ T cells into effector or memory populations requires dynamic remodeling of cellular metabolism and proteome composition. In a recent study published in Nature Immunology, Sinclair et al offer critical insights into the role of autophagy, particularly mitophagy, in regulating these processes during CD8+ T cell differentiation. Autophagy, a conserved catabolic mechanism, is traditionally associated with cellular homeostasis and survival during nutrient deprivation. In contrast, Sinclair et al reveal that, in the immune system, autophagy is not simply a survival mechanism but a fine-tuned regulator of CD8+ T cell metabolism and function, fine-tuning CD8+ T cell effector vs quiescence choices.

Objective To provide a comprehensive analysis of initial suicide attempts, covering incidence, risk factors, outcomes, and healthcare use in the month before and the month after the attempts. Design Comprehensive analysis of the Swedish population that included three designs: a retrospective cohort study to investigate incidence and healthcare use, a nested case-control study to investigate risk factors, and a matched cohort study to examine subsequent suicide attempts and mortality. Setting Comprehensive Swedish national registers that include patient diagnoses from hospitals and specialist outpatient care, and cause of death information updated to the end of 2019. Participants 3.7 million people born in Sweden in 1963-98 and followed from age 10 to 57 years. Main outcome measure First lifetime suicide attempt identified in patient and death registers using ICD (international classification of diseases) codes for intentional self-harm, any self-harm with lethal methods or requiring hospital admission, or any self-harm resulting in death. Results The lifetime risk of an initial suicide attempt in the study population was 4.6%, with greater risk in females and highest risk between ages 18 and 24. One in 10 families in Sweden had at least one family member who attempted suicide. Overdose and poisoning were the most common methods. Previous psychiatric disorders, general medical diseases, and adverse life events were associated with increased risk of initial suicide attempt, while higher socioeconomic status was associated with decreased risk. People with an initial suicide attempt were at substantially increased risk of subsequent attempts (hazard ratio 23.4), death by suicide (16.4), and all cause mortality (7.3). At least 60% of those who made an initial suicide attempt had a healthcare contact in the month before the attempt. Conclusions This study provides comprehensive data on the incidence, risk factors, outcomes, and healthcare use of initial suicide attempts in the Swedish population, highlighting the need for systematic prevention efforts for people who have attempted suicide for the first time.