Cancer immunotherapy is increasingly used in clinical practice, but its success rate is reduced by tumor escape from the immune system. This may be due to the genetic instability of tumor cells, which allows them to adapt to the immune response and leads to intratumoral immune heterogeneity. The study investigated spatial immune heterogeneity in the tumor microenvironment and its possible drivers in a mouse model of tumors induced by human papillomaviruses (HPV) following immunotherapy. Gene expression was determined by RNA sequencing and mutations by whole exome sequencing. A comparison of different tumor areas revealed heterogeneity in immune cell infiltration, gene expression, and mutation composition. While the mean numbers of mutations with every impact on gene expression or protein function were comparable in treated and control tumors, mutations with high or moderate impact were increased after immunotherapy. The genes mutated in treated tumors were significantly enriched in genes associated with ECM metabolism, degradation, and interactions, HPV infection and carcinogenesis, and immune processes such as antigen processing and presentation, Toll-like receptor signaling, and cytokine production. Gene expression analysis of DNA damage and repair factors revealed that immunotherapy upregulated Apobec1 and Apobec3 genes and downregulated genes related to homologous recombination and translesion synthesis. In conclusion, this study describes the intratumoral immune heterogeneity, that could lead to tumor immune escape, and suggests the potential mechanisms involved.

• MeSH
• imunoterapie * metody   MeSH
• infekce papilomavirem imunologie   virologie   MeSH
• lidé MeSH
• modely nemocí na zvířatech * MeSH
• mutace * MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové mikroprostředí * imunologie   MeSH
• regulace genové exprese u nádorů MeSH
• sekvenování exomu MeSH
• únik nádoru z imunitní kontroly genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Idiopatické střevní záněty, ulcerózní kolitida a Crohnova nemoc jsou celoživotní zánětlivá onemocnění s genetickým podkladem. Při kontaktu imunitního systému trávicí trubice s antigeny zevního prostředí a za spoluúčasti vlastní přirozené mikroflóry dochází ke ztrátě imunitní tolerance, selhání bariérové funkce střeva a k rozvoji poškozujícího zánětu s manifestací idiopatických střevních zánětů. Optimálních výsledků léčby dosahuje i přes pokroky ve vývoji biologické a cílené terapie cca třetina pacientů. Mirikizumab je první monoklonální protilátka proti p19 podjednotce IL-23, schválená pro léčbu UC v ČR. V naší kazuistice přinášíme zkušenosti s mirikizumabem v léčbě pacienta s refrakterní ulcerózní kolitidou.

Inflammatory bowel disease, ulcerative colitis and Crohn’s disease, are lifelong inflammatory diseases with a genetic basis. When the immune system of the digestive tract comes into contact with antigens from the external environment and the participation of its own natural microflora, there is a loss of immune tolerance, failure of the intestinal barrier function and the development of damaging inflammation with the manifestation of inflammatory bowel disease. Optimal treatment results, despite advances in the development of biological and targeted therapy, are achieved by approximately 1/3 of patients. Mirikizumab is the first monoclonal antibody against the p19 subunit of interleukin 23 approved for the treatment of ulcerative colitis in the Czech Republic. In our case study, we present our experience with mirikizumab in the treatment of a patient with refractory ulcerative colitis.

• Klíčová slova
• mirikizumab,
• MeSH
• dítě MeSH
• humanizované monoklonální protilátky farmakologie   terapeutické užití   MeSH
• lidé MeSH
• ulcerózní kolitida * farmakoterapie   patofyziologie   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

Interferon‐induced transmembrane proteins (IFITMs) are frequently overexpressed in cancer cells, including cervical carcinoma cells, and play a role in the progression of various cancer types. However, their mechanisms of action remain incompletely understood. In the present study, by employing a combination of surface membrane protein isolation and quantitative mass spectrometry, it was comprehensively described how the IFITM1 protein influences the composition of the cervical cancer cell surfaceome. Additionally, the effects of interferon‐γ on protein expression and cell surface exposure were evaluated in the presence and absence of IFITM1. The IFITM1‐regulated membrane and membrane‐associated proteins identified are involved mainly in processes such as endocytosis and lysosomal transport, cell‐cell and cell‐extracellular matrix adhesion, antigen presentation and the immune response. To complement the proteomic data, gene expression was analyzed using reverse transcription‐quantitative PCR to distinguish whether the observed changes in protein levels were attributable to transcriptional regulation or differential protein dynamics. Furthermore, the proteomic and gene expression data are supported by functional studies demonstrating the impact of the IFITM1 and IFITM3 proteins on the adhesive, migratory and invasive capabilities of cervical cancer cells, as well as their interactions with immune cells.

• MeSH
• buněčná adheze MeSH
• diferenciační antigeny * metabolismus   genetika   MeSH
• fenotyp MeSH
• interferon gama farmakologie   metabolismus   MeSH
• lidé MeSH
• membránové proteiny * metabolismus   genetika   MeSH
• nádorové buněčné linie MeSH
• nádory děložního čípku * patologie   genetika   metabolismus   imunologie   MeSH
• pohyb buněk MeSH
• proteiny vázající RNA * metabolismus   genetika   MeSH
• proteom * MeSH
• proteomika metody   MeSH
• regulace genové exprese u nádorů MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

AIMS: This study aimed to examine changes in the repertoire of functional T-cells specific for six leukemia-associated antigens (LAA), including WT1, PRAME, MUC1, CCNA1, NPM1, and NPM1c, during immune reconstitution following allogeneic transplantation of hematopoietic stem cells (HSCT) in patients with acute myeloid leukemia. PATIENTS & METHODS: LAA-specific T cell response was measured by ELISPOT- IFNγ and intracellular cytokine staining in 47 patients before starting conditioning therapy (baseline) and 7 months after HSCT. RESULTS: The positive cumulative LAA-specific T cell response before HSCT was associated with a decreased risk of relapse after HSCT. The prevalent genetic aberration - an internal tandem duplication of Fms 3 - related receptor tyrosine kinase, which has been previously implicated in immune escape mechanisms, is presented here for the first time as a factor associated with the absence of an adaptive T cell response against multiple LAAs. T-cell specific responses against wild-type and mutated NPM1 antigens were less frequent in the study cohort and did not correlate with mutations in the NPM1 gene. CONCLUSIONS: Our results showed that the T-cell response to LAA can be reconstituted after HSCT. Measurement of functional pre-transplant T-cell responses against multiple LAAs could help to find patients with an increased risk of relapse.

• MeSH
• akutní myeloidní leukemie * terapie   imunologie   genetika   MeSH
• antigeny nádorové imunologie   MeSH
• dospělí MeSH
• homologní transplantace MeSH
• jaderné proteiny genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mucin 1 genetika   imunologie   MeSH
• mutace * MeSH
• nukleofosmin * MeSH
• proteiny WT1 imunologie   genetika   MeSH
• recidiva MeSH
• senioři MeSH
• T-lymfocyty * imunologie   MeSH
• transplantace hematopoetických kmenových buněk * MeSH
• tyrosinkinasa 3 podobná fms * genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Antisense transcripts play an important role in generating regulatory non-coding RNAs but whether these transcripts are also translated to generate functional peptides remains poorly understood. In this study, RNA sequencing and six-frame database generation were combined with mass spectrometry analysis of peptides isolated from polysomes to identify Nascent Pioneer Translation Products (Na-PTPs) originating from alternative reading frames of bi-directional transcripts. Two Na-PTP originating peptides derived from antisense strands stimulated CD8+ T cell proliferation when presented to peripheral blood mononuclear cells (PBMCs) from nine healthy donors. Importantly, an antigenic peptide derived from the reverse strand of two cDNA constructs was presented on MHC-I molecules and induced CD8+ T cell activation. The results demonstrate that three-frame translation of bi-directional transcripts generates antigenic peptide substrates for the immune system. This discovery holds significance for understanding the origin of self-discriminating peptide substrates for the major histocompatibility class I (MHC-I) pathway and for enhancing immune-based therapies against infected or transformed cells.

• MeSH
• aktivace lymfocytů imunologie   MeSH
• antisense RNA * genetika   imunologie   MeSH
• CD8-pozitivní T-lymfocyty * imunologie   MeSH
• leukocyty mononukleární imunologie   MeSH
• lidé MeSH
• MHC antigeny I. třídy * imunologie   genetika   MeSH
• peptidy * imunologie   genetika   MeSH
• prezentace antigenu MeSH
• proteosyntéza * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Mikroorganismy si během evoluce vyvinuly širokou škálu strategií, jak uniknout vrozenému i adaptivnímu imunitnímu systému, a některým těmto strategiím se věnujeme v našem přehledu. Mikroorganismy mohou využívat podobnost svých proteinů s proteiny hostitele, produkovat protizánětlivé faktory, narušovat komplementový systém, ovlivňovat funkci a blokovat syntézu cytokinů, inhibovat rozpoznávání imunoglobulinů, snižovat expresi a modifikovat antigeny na svém povrchu, narušovat zpracování a prezentaci antigenu imunitními buňkami, vstupovat do imunitních buněk, ovlivňovat apoptózu buněk, modulovat funkce imunitních buněk nebo ovlivňovat produkci hormonů. S těmito únikovými strategiemi je nutné počítat při léčbě infekčních onemocnění.

Microorganisms have evolved a wide variety of strategies to evade both the innate and adaptive immune systems during evolution, and some of these strategies are addressed in our review. Microorganisms can use the similarity of their proteins to host proteins, produce anti-inflammatory factors, disrupt the complement system, affect the function and block the synthesis of cytokines, inhibit the recognition of immunoglobulins, reduce the expression and modify antigens on their surface, disrupt the processing and presentation of antigen by immune cells, enter immune cells , influence cell apoptosis, modulate immune cell functions or influence hormone production. These escape strategies must be taken into account when treating infectious diseases.

• Klíčová slova
• únikové strategie mikroorganismů,
• MeSH
• interakce hostitele a patogenu MeSH
• lidé MeSH
• mikrobiologické jevy * MeSH
• přirozená imunita * MeSH
• trénovaná imunita MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

Intestinal epithelial cells have the capacity to upregulate MHCII molecules in response to certain epithelial-adhesive microbes, such as segmented filamentous bacteria (SFB). However, the mechanism regulating MHCII expression as well as the impact of epithelial MHCII-mediated antigen presentation on T cell responses targeting those microbes remains elusive. Here, we identify the cellular network that regulates MHCII expression on the intestinal epithelium in response to SFB. Since MHCII on the intestinal epithelium is dispensable for SFB-induced Th17 response, we explored other CD4+ T cell-based responses induced by SFB. We found that SFB drive the conversion of cognate CD4+ T cells to granzyme+ CD8α+ intraepithelial lymphocytes. These cells accumulate in small intestinal intraepithelial space in response to SFB. Yet, their accumulation is abrogated by the ablation of MHCII on the intestinal epithelium. Finally, we show that this mechanism is indispensable for the SFB-driven increase in the turnover of epithelial cells in the ileum. This study identifies a previously uncharacterized immune response to SFB, which is dependent on the epithelial MHCII function.

• MeSH
• Bacteria MeSH
• CD4-pozitivní T-lymfocyty * MeSH
• epitelové buňky MeSH
• granzymy MeSH
• prezentace antigenu * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Glial cells expressing neuron-glial antigen 2 (NG2), also known as oligodendrocyte progenitor cells (OPCs), play a critical role in maintaining brain health. However, their ability to differentiate after ischemic injury is poorly understood. The aim of this study was to investigate the properties and functions of NG2 glia in the ischemic brain. Using transgenic mice, we selectively labeled NG2-expressing cells and their progeny in both healthy brain and after focal cerebral ischemia (FCI). Using single-cell RNA sequencing, we classified the labeled glial cells into five distinct subpopulations based on their gene expression patterns. Additionally, we examined the membrane properties of these cells using the patch-clamp technique. Of the identified subpopulations, three were identified as OPCs, whereas the fourth subpopulation had characteristics indicative of cells likely to develop into oligodendrocytes. The fifth subpopulation of NG2 glia showed astrocytic markers and had similarities to neural progenitor cells. Interestingly, this subpopulation was present in both healthy and post-ischemic tissue; however, its gene expression profile changed after ischemia, with increased numbers of genes related to neurogenesis. Immunohistochemical analysis confirmed the temporal expression of neurogenic genes and showed an increased presence of NG2 cells positive for Purkinje cell protein-4 at the periphery of the ischemic lesion 12 days after FCI, as well as NeuN-positive NG2 cells 28 and 60 days after injury. These results suggest the potential development of neuron-like cells arising from NG2 glia in the ischemic tissue. Our study provides insights into the plasticity of NG2 glia and their capacity for neurogenesis after stroke.

• MeSH
• antigeny metabolismus   MeSH
• astrocyty metabolismus   MeSH
• ischemie mozku * metabolismus   MeSH
• mozek metabolismus   MeSH
• myši transgenní MeSH
• myši MeSH
• nervové kmenové buňky * metabolismus   MeSH
• neuroglie metabolismus   MeSH
• oligodendroglie metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Lck, a member of the Src kinase family, is a non-receptor tyrosine kinase involved in immune cell activation, antigen recognition, tumor growth, and cytotoxic response. The enzyme has usually been linked to T lymphocyte activation upon antigen recognition. Lck activation is central to CD4, CD8, and NK activation. However, recently, it has become clearer that activating the enzyme in CD8 cells can be independent of antigen presentation and enhance the cytotoxic response. The role of Lck in NK cytotoxic function has been controversial in a similar fashion as the role of the enzyme in CAR T cells. Inhibiting tyrosine kinases has been a highly successful approach to treating hematologic malignancies. The inhibitors may be useful in treating other tumor types, and they may be useful to prevent cell exhaustion. New, more selective inhibitors have been documented, and they have shown interesting activities not only in tumor growth but in the treatment of autoimmune diseases, asthma, and graft vs. host disease. Drug repurposing and bioinformatics can aid in solving several unsolved issues about the role of Lck in cancer. In summary, the role of Lck in immune response and tumor growth is not a simple event and requires more research.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Antigen-presenting cells (APCs) are master regulators of the immune response by directly interacting with T cells to orchestrate distinct functional outcomes. Several types of professional APC exist, including conventional dendritic cells, B cells and macrophages, and numerous other cell types have non-classical roles in antigen presentation, such as thymic epithelial cells, endothelial cells and granulocytes. Accumulating evidence indicates the presence of a new family of APCs marked by the lineage-specifying transcription factor retinoic acid receptor-related orphan receptor-γt (RORγt) and demonstrates that these APCs have key roles in shaping immunity, inflammation and tolerance, particularly in the context of host-microorganism interactions. These RORγt+ APCs include subsets of group 3 innate lymphoid cells, extrathymic autoimmune regulator-expressing cells and, potentially, other emerging populations. Here, we summarize the major findings that led to the discovery of these RORγt+ APCs and their associated functions. We discuss discordance in recent reports and identify gaps in our knowledge in this burgeoning field, which has tremendous potential to advance our understanding of fundamental immune concepts.

• MeSH
• antigen prezentující buňky metabolismus   MeSH
• endoteliální buňky MeSH
• jaderné receptory - podrodina 1, skupina F, člen 3 * metabolismus   MeSH
• lidé MeSH
• lymfocyty * MeSH
• přirozená imunita MeSH
• transportní proteiny metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH