Utilisation of cytological samples for multiplex immunofluorescence assay.

OBJECTIVE: Understanding the immune environment of non-small cell lung cancer (NSCLC) is important for designing effective anticancer immunotherapies. We describe the use of multiplex immunofluorescence (mIF) assays to enable characterisation of the tumour-infiltrating immune cells and their interactions, both across and within immune subtypes. METHODS: Six cytological samples of NSCLC taken by transoesophageal ultrasound-guided fine needle aspiration were tested with an mIF assay designed to detect the expression of key immune cell markers such as CD3, CD8, CD20, CD11b, and CD68. Pan-cytokeratin was used to detect the NSCLC cells. Fluorescence images were acquired on a Vectra-Polaris Automated Quantitative Pathology Imaging System (Akoya Biosciences). RESULTS: MIF assay was able to reliably detect and quantify the myeloid cell markers CD11b, CD68, CD3+ and CD8+ T cells, and CD20+ B lymphocytes on cytological samples of NSCLC. Whole-tissue analysis and its correlation with the corresponding H&E stains allowed a better understanding of the tissue morphology and the relationship between tumour and stroma compartments. Additionally, a uniform, specific, and correct staining pattern was seen for every immune marker. CONCLUSION: The implementation of mIF assay on cytological samples taken with minimally invasive methods seems feasible and can be used to explore the immune environment of NSCLC.

Association between adipophilin expression and risk of dyslipidaemia in patients with granuloma annulare.

BACKGROUND: An association between granuloma annulare (GA) and dyslipidaemia has been reported. Adipophilin expression may play a plausible role as a cutaneous biomarker for dyslipidaemia in patients with GA; however, this potential link remains to be explored. METHODS: Patients with GA were identified at our hospital between January 1, 1990, and December 31, 2021, with a thorough review of their clinical and histological characteristics. Adipophilin staining was assessed in biopsies of GA lesions. RESULTS: A total of 107 patients with GA were included. The prevalence of dyslipidaemia in patients with positive adipophilin staining was clearly higher than in those with negative labelling (62.3% vs 13.3%). Relative to the dyslipidaemia risk for patients with negative adipophilin expression, the odds for patients with positive adipophilin expression were increased 10-fold (OR: 10.8; p-value<.01). We identified 23 incident cases of dyslipidaemia over a median follow-up period of 91 months among 54 patients with no history of dyslipidaemia. The patients with positive adipophilin expression showed a higher risk of developing dyslipidaemia (HR: 8.9; p-value<.01). CONCLUSIONS: Patients with positive adipophilin staining in their GA biopsies were found to be associated with a higher risk for both baseline and incident dyslipidaemia.

Osteoclast-rich undifferentiated carcinoma of the bladder and the diagnostic usefulness of immunohistochemistry. A case report.

Osteoclast-rich undifferentiated carcinoma (ORUC) of the urinary tract is a rare variant of urothelial carcinoma, first described in 1985 by Kitazawa et al. It has a worse prognosis compared to other histological variants of invasive urothelial carcinoma and its diagnosis may prove challenging due to the variability in its immunohistochemical profile. We present a case of ORUC in which GATA3 immunostaining was a useful diagnostic tool.

Neutrophil Extracellular Traps, Local IL-8 Expression, and Cytotoxic T-Lymphocyte Response in the Lungs of Patients With Fatal COVID-19.

BACKGROUND: Excessive inflammation is pathogenic in the pneumonitis associated with severe COVID-19. Neutrophils are among the most abundantly present leukocytes in the inflammatory infiltrates and may form neutrophil extracellular traps (NETs) under the local influence of cytokines. NETs constitute a defense mechanism against bacteria, but have also been shown to mediate tissue damage in a number of diseases. RESEARCH QUESTION: Could NETs and their tissue-damaging properties inherent to neutrophil-associated functions play a role in the respiratory failure seen in patients with severe COVID-19, and how does this relate to the SARS-CoV-2 viral loads, IL-8 (CXCL8) chemokine expression, and cytotoxic T-lymphocyte infiltrates? STUDY DESIGN AND METHODS: Sixteen lung biopsy samples obtained immediately after death were analyzed methodically as exploratory and validation cohorts. NETs were analyzed quantitatively by multiplexed immunofluorescence and were correlated with local levels of IL-8 messenger RNA (mRNA) and the density of CD8+ T-cell infiltration. SARS-CoV-2 presence in tissue was quantified by reverse-transcriptase polymerase chain reaction and immunohistochemistry analysis. RESULTS: NETs were found in the lung interstitium and surrounding the bronchiolar epithelium with interindividual and spatial heterogeneity. NET density did not correlate with SARS-CoV-2 tissue viral load. NETs were associated with local IL-8 mRNA levels. NETs were also detected in pulmonary thrombi and in only one of eight liver tissues. NET focal presence correlated negatively with CD8+ T-cell infiltration in the lungs. INTERPRETATION: Abundant neutrophils undergoing NETosis are found in the lungs of patients with fatal COVID-19, but no correlation was found with viral loads. The strong association between NETs and IL-8 points to this chemokine as a potentially causative factor. The function of cytotoxic T-lymphocytes in the immune responses against SARS-CoV-2 may be interfered with by the presence of NETs.