Purpose: Weight loss is a well-recognized prognostic parameter for survival of lung cancer patients. Computerized-tomography (CT)-based analysis of body composition and blood-based metabolic evaluation are promising prognostic tools. We aimed to assess the correlation between albumin, body mass index (BMI), skeletal muscle mass index (SMI), fat-free mass index (FFMI), fat mass index (FMI) and weight change, as well as their correlation with survival of lung cancer patients on nivolumab treatment. Methods: Data were retrospectively collected. Weight was measured at a diagnosis of stage 4 disease and before start of nivolumab. Albumin levels were measured before starting nivolumab. BMI, SMI, FFMI, and FMI were evaluated from CT scans performed at start of nivolumab. Overall survival (OS) was from starting of nivolumab to death or censured at last follow-up. Statistical analysis was done to identify correlation between the various factors and between those factors and survival. Results: Forty-six patients with advanced non-small cell lung cancer (NSCLC) were included. Median follow-up was 22 months. Pathology was Adenocarcinoma/Squamous/non-other specified in 25/15/6 respectively. All patients received nivolumab as an advanced-line treatment for stage IV NSCLC. We observed a significant correlation of weight loss (P=0.01, HR=2.85) and albumin (P=0.043, HR=0.34) with OS in multivariate analysis. A significant correlation was found between BMI to SMI, FFMI, FMI, and weight change. Conclusion: Weight loss and low albumin levels are significant negative prognostic factors for NSCLC patients on immunotherapy. CT-based parameters of body composition remain to be proven as more reliable than standard clinical parameters.

Significance: We performed a screen to identify unique proteins regulating T-cell adhesion downstream of the chemokine receptor CXCR4. We identified that the guanine exchange factor mediating stromal cell-derived factor 1 alpha (SDF-1α)/C-X-C chemokine receptor type 4 (CXCR4) activation is phospholipase Cε 1 (PLCε1). Experiments to separate the dual-enzymatic function of PLCε1 uncover necessary contributions of the CDC25, Pleckstrin homology, and Ras-associating domains, but not phospholipase activity, to its guanine exchange activity. In the mouse model of contact sensitivity, we have shown a necessary role for PLCε1 in T-cell recruitment to the site of secondary challenge, but not for priming after antigen sensitization. We uncover a signaling pathway that mediates SDF-1α–induced T-cell adhesion and suggest that PLCε1 is a potential specific target for future antiinflammatory drugs.

The inhibitory receptor PD-1 is expressed on T cells to inhibit select functions when ligated. The complete signaling mechanism downstream of PD-1 has yet to be uncovered. Here, we discovered phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (PAG) is phosphorylated following PD-1 ligation and associate this with inhibitory T cell function. Clinical cohort analysis correlates low PAG expression with increased survival from numerous tumor types. PAG knockdown in T cells prevents PD-1-mediated inhibition of cytokine secretion, cell adhesion, CD69 expression, and ERK_204/187 phosphorylation, and enhances phosphorylation of SRC₅₂₇ following PD-1 ligation. PAG overexpression rescues these effects. In vivo, PAG contributes greatly to the growth of two murine tumors, MC38 and B16, and limits T cell presence within the tumor. Moreover, PAG deletion sensitizes tumors to PD-1 blockade. Here PAG is established as a critical mediator of PD-1 signaling and as a potential target to enhance T cell activation in tumors.

Background: Soluble human leucocyte antigen (sHLA) molecules, released into the plasma, carry their original peptide cargo and provide insight into the protein synthesis and degradation schemes of their source cells and tissues. Other body fluids, such as pleural effusions, may also contain sHLA-peptide complexes, and can potentially serve as a source of tumor antigens since these fluids are drained from the tumor microenvironment. We explored this possibility by developing a methodology for purifying and analyzing large pleural effusion sHLA class I peptidomes of patients with malignancies or benign diseases. Methods: Cleared pleural fluids, cell pellets present in the pleural effusions, and the primary tumor cells cultured from cancer patients’ effusions, were used for immunoaffinity purification of the HLA molecules. The recovered HLA peptides were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and the resulting LC-MS/MS data were analyzed with the MaxQuant software tool. Selected tumor antigen peptides were tested for their immunogenicity potential with donor peripheral blood mononuclear cells (PBMCs) in an in vitro assay. Results: Mass spectrometry analysis of the pleural effusions revealed 39,669 peptides attributable to 11,305 source proteins. The majority of peptides identified from the pleural effusions were defined as HLA ligands that fit the patients’ HLA consensus sequence motifs. The membranal and soluble HLA peptidomes of each individual patient correlated to each other. Additionally, soluble HLA peptidomes from the same patient, obtained at different visits to the clinic, were highly similar. Compared with benign effusions, the soluble HLA peptidomes of malignant pleural effusions were larger and included HLA peptides derived from known tumor-associated antigens, including cancer/testis antigens, lung-related proteins, and vascular endothelial growth factor pathway proteins. Selected tumor-associated antigens that were identified by the immunopeptidomics were able to successfully prime CD8⁺ T cells. Conclusions: Pleural effusions contain sHLA-peptide complexes, and the pleural effusion HLA peptidome of patients with malignant tumors can serve as a rich source of biomarkers for tumor diagnosis and potential candidates for personalized immunotherapy.

Background Methacholine challenge tests (MCTs) are used to diagnose airway hyperresponsiveness (AHR) in patients with suspected asthma where previous diagnostic testing has been inconclusive. The test is time consuming and usually requires referral to specialized centers. Simple methods to predict AHR could help determine which patients should be referred to MCTs, thus avoiding unnecessary testing. Here we investigated the potential use of baseline spirometry variables as surrogate markers for AHR in adults with suspected asthma. Methods Baseline spirometry and MCTs performed between 2013 and 2019 in a large tertiary center were retrospectively evaluated. Receiver-operating characteristic curves for the maximal expiratory flow-volume curve indices (angle beta, FEV1, FVC, FEV1/FVC, FEF50%, FEF25-75%) were constructed to assess their overall accuracy in predicting AHR and optimal cutoff values were identified. Results A total of 2983 tests were analyzed in adults aged 18-40 years. In total, 14% of all MCTs were positive (PC20 <= 16 mg/ml). All baseline spirometry parameters were significantly lower in the positive group (p < 0.001). FEF50% showed the best overall accuracy (AUC = 0.688) and proved to be useful as a negative predictor when applying FEF50% >= 110% as a cutoff level. Conclusions This study highlights the role of FEF50% in predicting AHR in patients with suspected asthma. A value of >= 110% for baseline FEF50% could be used to exclude AHR and would lead to a substantial decrease in MCT referrals.

Background: Respiratory Syncytial Virus (RSV) is a significant cause of morbidity and mortality among lung transplant (LTx) recipients. Therapeutic options are limited, emphasizing the importance of prevention. The Arexvy^® vaccine (RSVPreF3) showed promising efficacy among immunocompetent adults; however, data on its immunogenicity in solid organ transplant recipients remain unclear. Methods: A single-center retrospective cohort study, including all LTx recipients who were vaccinated with Arexvy in February 2024. Baseline and follow-up serum samples (1, 3, and 6 months post-vaccination) were analyzed for antibody responses using a commercial RSV ELISA kit and micro-neutralization assays against historical reference RSV A/B ATCC strains and seasonal RSV strains. Adverse events were documented. Results: A total of 28 recipients received the vaccine. Twenty-one (75%) were male, and the median age was 62 years (interquartile range [IQR], 53–67). The median time from transplant was 486 days (IQR, 243–966). Vaccination elicited strong immunogenic responses, demonstrating a twofold increase in ELISA-determined antibody levels at one month post-vaccination, which were sustained for six months. At one month, 67% of recipients had antibody levels exceeding the cutoff threshold. Micro-neutralization assays showed a significant increase in neutralizing antibodies against all tested variants (RSV A/B ATCC and seasonal RSV A/B), with titers remaining at least twofold higher than pre-vaccination levels. No serious adverse events were observed. Conclusions: Our findings demonstrate a sustained antibody response to the Arexvy^® vaccine in a cohort of LTx recipients, with antibody titers sustained over six months. Further research is needed to assess the long-term durability of the immune response and the potential immunogenicity of this vaccine in LTx populations.