Immune checkpoint therapies have significantly advanced cancer treatment. Nevertheless, the high costs and potential adverse effects associated with these therapies highlight the need for better ...predictive biomarkers to identify patients who are most likely to benefit from treatment. Unfortunately, the existing biomarkers are insufficient to identify such patients. New high-dimensional spatial technologies have emerged as a valuable tool for discovering novel biomarkers by analysing multiple protein markers at a single-cell resolution in tissue samples. These technologies provide a more comprehensive map of tissue composition, cell functionality, and interactions between different cell types in the tumour microenvironment. In this review, we provide an overview of how spatial protein-based multiplexing technologies have fuelled biomarker discovery and advanced the field of immunotherapy. In particular, we will focus on how these technologies contributed to (i) characterise the tumour microenvironment, (ii) understand the role of tumour heterogeneity, (iii) study the interplay of the immune microenvironment and tumour progression, (iv) discover biomarkers for immune checkpoint therapies (v) suggest novel therapeutic strategies.
Chronic liver injury, as observed in non-alcoholic steatohepatitis (NASH), progressive fibrosis, and cirrhosis, remains poorly treatable. Steatohepatitis causes hepatocyte loss in part by a direct ...lipotoxic insult, which is amplified by derangements in the non-parenchymal cellular (NPC) interactive network wherein hepatocytes reside, including, hepatic stellate cells, liver sinusoidal endothelial cells and liver macrophages. To create an in vitro culture model encompassing all these cells, that allows studying liver steatosis, inflammation and fibrosis caused by NASH, we here developed a fully defined hydrogel microenvironment, termed hepatocyte maturation (HepMat) gel, that supports maturation and maintenance of pluripotent stem cell (PSC) derived hepatocyte- and NPC-like cells for at least one month. The HepMat-based co-culture system modeled key molecular and functional features of TGFβ-induced liver fibrosis and fatty-acid induced inflammation and fibrosis better than monocultures of its constituent cell populations. The novel co-culture system should open new avenues for studying mechanisms underlying liver steatosis, inflammation and fibrosis as well as for assessing drugs counteracting these effects.
Congenital melanocytic nevus syndrome (CMNS) is a rare condition characterized by pigmented skin lesions that are usually present at birth and are associated with an increased risk of neurological ...abnormalities and malignant melanoma. It mostly results from a post‐zygotic NRAS mutation of neural‐derived crest cells, leading to uncontrolled cell growth. Because of the increased knowledge of the genetics underlying CMNS, targeted therapy becomes a promising treatment option. We present a case of CMNS in a newborn. Physical examination at birth showed a giant congenital melanocytic nevus, extending from the occipital to the lower lumbar region. A magnetic resonance imaging scan revealed multiple cerebral and cerebellar parenchymal lesions. Genetic analysis of the cutaneous lesions showed the presence of an NRAS Q61R mutation. The patient was treated with dermabrasion to reduce the color intensity of the nevus. However, this was complicated by recurrent wound infections and laborious wound healing. At the age of 1 year, the patient had an age‐appropriate psychomotor development, without neurological deficits.
The lack of T-cell infiltrates is a major obstacle to effective immunotherapy in cancer. Conversely, the formation of tumor-associated tertiary-lymphoid-like structures (TA-TLLS), which are the local ...site of humoral and cellular immune responses against cancers, are associated with good prognosis and have recently been detected in Immune Checkpoint Blockade (ICB)-responding patients. However, how these lymphoid aggregates develop remains poorly understood. By employing single-cell transcriptomics, endothelial fate mapping, and functional multiplex immune profiling, we demonstrate that antiangiogenic immune-modulating therapies evoke transdifferentiation of postcapillary venules into inflamed high-endothelial venules (HEV) via LT/LTβR signaling. In turn, tumor-HEVs boost intratumoral lymphocyte influx and foster permissive lymphocyte niches for PD1
−
and PD1
+
TCF1
+
CD8 T cell progenitors that differentiate into GrzB
+
PD1
+
CD8 T effector cells. Tumor-HEVs require continuous CD8 and NK cell-derived signals revealing that tumor-HEV maintenance is actively sculpted by the adaptive immune system through a feed-forward loop.
Hua & Vella et al. reveal that effective antiangiogenic immunotherapy differentiates postcapillary venules into high-endothelial venules (HEV) by lymphotoxin beta receptor activation emanating from CD8 T and NK cell-derived signals. TU-HEVs establish perivascular niches in which TCF1
+
PD1
+
lymphocytes expand and produce cytotoxic PD1
+
TIM3
+
lymphocytes that may facilitate anti-tumoral immunity.
Abstract
Background and Aims
Acute kidney injury is common in patients infected with the novel coronavirus SARS-CoV-2. Predominant findings in case series of kidney biopsies include acute tubular ...injury and collapsing podocytopathy. We performed single-cell RNA sequencing on kidney biopsy of a patient with COVID19-associated Henoch-Schönlein vasculitis, to investigate the underlying molecular changes.
Method
A 46-year-old woman presented with cutaneous vasculitis, arthritis, fever and microscopic hematuria. SARS-CoV-2 PCR on nasopharyngeal swab turned positive. Despite quick spontaneous resolution of symptoms, hematuria persisted and proteinuria increased in the next weeks. Subsequent kidney biopsy showed IgA nephropathy. Kidney biopsy was dissociated into a single-cell suspension and RNA was sequenced. 6126 kidney cells passed quality filters. Publicly available single cell sequencing data of 3 healthy kidney samples were integrated to allow comparison. The skin biopsy, performed at the initial presentation, was stained for the SARS-CoV-2 spike protein and the ACE2 protein using immunohistochemistry.
Results
Unsupervised clustering analysis of kidney identified 12 distinct cell types (Figure 1). T-lymphocytes were significantly enriched in COVID19 associated IgA nephropathy (16.7% versus 0.5%, 1.2% and 4.1% in healthy kidney, IgA nephropathy/healthy kidney ratio of relative % of T-/NK-cell clusters of 8.5), with a deviation towards CD8 lymphocytes and NK(T) cells (Figure 2). NK cells were solely present in IgA nephropathy compared to healthy kidney (1.5% versus 0% in all healthy kidneys).
Several genes involved in immune activation, oxidative stress and injury were upregulated in podocytes and mesangial cells. For example, one of the genes upregulated in podocytes was macrophage migration inhibitory factor (MIF) which is known to be involved in podocyte injury and mesangial sclerosis. In endothelial cells pathways involved in NK cell immunity, antigen presentation, interferon gamma signaling, and viral entry were upregulated. In T lymphocytes pathways of antigen presentation and T cell cytotoxicity were enriched.
In the skin biopsy, immunohistochemistry was positive for SARS-CoV-2 spike protein inside inflammatory cells, while the ACE2 receptor was positive in the same inflammatory cells, as well as inside endothelial cells.
Conclusion
Although both innate and adaptive immunity are considered to be involved in IgA nephropathy, our single cell sequencing data demonstrates that mainly T-lymphocytes, especially CD8 cells and NK cells, are enriched in COVID19 associated IgA nephropathy. Further elucidation of the involved pathways and the T cell receptor is planned. Interestingly, the SARS-CoV-2 virus could be identified inside the inflammatory cells in the skin in the context of cutaneous vasculitis, suggesting a direct pathologic effect.
Abstract A retrospective study correlating the diagnosis made on core needle breast biopsy (CNB) with the diagnosis made on the final surgical specimen was done using the British National Health ...Service Breast Cancer Screening Programme (NHSBSP) classification for CNB on 226 patients during a period of 15 months. Statistical analysis was used to evaluate sensitivity, specificity, and positive and negative predictive values of the NHSBSP diagnostic categories. Cohen κ was used to evaluate the agreement between the diagnosis on CNB and the final pathologic diagnosis in “clinically positive cases.” Finally, a comparative analysis between the CNB method and fine needle aspiration biopsy was made. The distribution of our cases for each diagnostic category reflects the literature guidelines, with minor differences in the B2 and B4 groups. Statistical data about the patients' follow-up revealed a small number of false-negative cases in the B1 and B2 categories and no false-positive cases in the B4 and B5 groups. Uncertain malignant lesions (B3 category) were divided into 3 major areas (papillary lesions, fibroepithelial proliferations with cellular stroma, and intraepithelial atypical lesions such as ductal intraepithelial neoplasia grade 1/lobular intraepithelial neoplasia grade 1). Of the 29 patients in the B3 category, 26 underwent surgery. Cohen κ analysis showed a strong statistical correlation ( κ = 0.77; Z = 4.3; significance >1.96; α = .05) between CNB diagnosis and surgical pathology final results in the subgroup of high-risk patients (diagnosis, ≥ductal intraepithelial neoplasia grade 1 on CNB). Global diagnostic power of CNB in all 226 cases revealed high sensitivity (88.3%) and slightly lower specificity (72.8%). In 42 “doubtful” cases, synchronous fine needle aspiration biopsy and CNB were performed, showing a complementary role in the diagnostic phase of breast lesions. Core needle breast biopsy represents the criterion standard method in the diagnostic phase of many breast tumors; the NHSBSP classification is a useful reporting system that provides a good standardization of the pathologic diagnosis and provides a clear guideline for the correct management of the patient.
When examining microscopically lymph nodes removed as part of the surgical therapy for thyroid carcinoma, one should be aware of the fact that high endothelial venules, when dilated and near the ...capsule, can lead to a wrong diagnosis of metastasis. We present a case in which such a situation arose.
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