| 1. |
- Assadi, Ghazaleh, et al.
(författare)
-
Functional Analyses of the Crohn's Disease Risk Gene LACC1
- 2016
-
Ingår i: PLOS ONE. - San Francisco, USA : Public Library of Science. - 1932-6203. ; 11:12
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Genetic variation in the Laccase (multicopper oxidoreductase) domain-containing 1 (LACC1) gene has been shown to affect the risk of Crohn's disease, leprosy and, more recently, ulcerative colitis and juvenile idiopathic arthritis. LACC1 function appears to promote fatty-acid oxidation, with concomitant inflammasome activation, reactive oxygen species production, and anti-bacterial responses in macrophages. We sought to contribute to elucidating LACC1 biological function by extensive characterization of its expression in human tissues and cells, and through preliminary analyses of the regulatory mechanisms driving such expression.Methods: We implemented Western blot, quantitative real-time PCR, immunofluorescence microscopy, and flow cytometry analyses to investigate fatty acid metabolism-immune nexus (FAMIN; the LACC1 encoded protein) expression in subcellular compartments, cell lines and relevant human tissues. Gene-set enrichment analyses were performed to initially investigate modulatory mechanisms of LACC1 expression. A small-interference RNA knockdown in vitro model system was used to study the effect of FAMIN depletion on peroxisome function.Results: FAMIN expression was detected in macrophage-differentiated THP-1 cells and several human tissues, being highest in neutrophils, monocytes/macrophages, myeloid and plasmacytoid dendritic cells among peripheral blood cells. Subcellular co-localization was exclusively confined to peroxisomes, with some additional positivity for organelle endomembrane structures. LACC1 co-expression signatures were enriched for genes involved in peroxisome proliferator-activated receptors (PPAR) signaling pathways, and PPAR ligands downregulated FAMIN expression in in vitro model systems.Conclusion: FAMIN is a peroxisome-associated protein with primary role(s) in macrophages and other immune cells, where its metabolic functions may be modulated by PPAR signaling events. However, the precise molecular mechanisms through which FAMIN exerts its biological effects in immune cells remain to be elucidated.
|
|
| 2. |
- Kokkinou, Efthymia, et al.
(författare)
-
CD45RA(+)CD62L(-) ILCs in human tissues represent a quiescent local reservoir for the generation of differentiated ILCs
- 2022
-
Ingår i: Science immunology. - : AMER ASSOC ADVANCEMENT SCIENCE. - 2470-9468. ; 7:70
-
Tidskriftsartikel (refereegranskat)abstract
- Innate lymphoid cells (ILCs) are highly plastic and predominantly mucosal tissue-resident cells that contribute to both homeostasis and inflammation depending on the microenvironment. The discovery of naive-like ILCs suggests an ILC differentiation process that is akin to naive T cell differentiation. Delineating the mechanisms that underlie ILC differentiation in tissues is crucial for understanding ILC biology in health and disease. Here, we showed that tonsillar ILCs expressing CD45RA lacked proliferative activity, indicative of cellular quiescence. CD62L distinguished two subsets of CD45RA(+) ILCs. CD45RA(+)CD62L(+) ILCs (CD62L(+) ILCs) resembled circulating naive ILCs because they lacked the transcriptional, metabolic, epigenetic, and cytokine production signatures of differentiated ILCs. CD45RA(+)CD62L(-) ILCs (CD62L(-) ILCs) were epigenetically similar to CD62L(+) ILCs but showed a transcriptional, metabolic, and cytokine production signature that was more akin to differentiated ILCs. CD62L(+) and CD62L(-) ILCs contained uni- and multipotent precursors of ILC1s/NK cells and ILC3s. Differentiation of CD62L(+) and CD62L(-) ILCs led to metabolic reprogramming including up-regulation of genes associated with glycolysis, which was needed for their effector functions after differentiation. CD62L(-) ILCs with preferential differentiation capacity toward IL-22-producing ILC3s accumulated in the inflamed mucosa of patients with inflammatory bowel disease. These data suggested distinct differentiation potential of CD62L(+) and CD62L(-) ILCs between tissue microenvironments and identified that manipulation of these cells is a possible approach to restore tissue-immune homeostasis.
|
|
| 3. |
- Maric, Jovana, et al.
(författare)
-
Cytokine-induced endogenous production of prostaglandin D-2 is essential for human group 2 innate lymphoid cell activation
- 2019
-
Ingår i: Journal of Allergy and Clinical Immunology. - : MOSBY-ELSEVIER. - 0091-6749 .- 1097-6825. ; 143:6, s. 2202-2214.e5
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: We set out to examine PG production in human ILC2s and the implications of such endogenous production on ILC2 function. Methods: The effects of the COX-1/2 inhibitor flurbiprofen, the hematopoietic prostaglandin D2 synthase (HPGDS) inhibitor KMN698, and the CRTH2 antagonist CAY10471 on human ILC2s were determined by assessing receptor and transcription factor expression, cytokine production, and gene expression with flow cytometry, ELISA, and quantitative RT-PCR, respectively. Concentrations of lipid mediators were measured by using liquid chromatography-tandem mass spectrometry and ELISA. Results: We show that ILC2s constitutively express HPGDS and upregulate COX-2 upon IL-2, IL-25, and IL-33 plus thymic stromal lymphopoietin stimulation. Consequently, PGD2 and its metabolites can be detected in ILC2 supernatants. We reveal that endogenously produced PGD2 is essential in cytokine-induced ILC2 activation because blocking of the COX-1/2 or HPGDS enzymes or the CRTH2 receptor abolishes ILC2 responses. Conclusion: PGD2 produced by ILC2s is, in a paracrine/autocrine manner, essential in cytokine-induced ILC2 activation. Hence we provide the detailed mechanism behind how CRTH2 antagonists represent promising therapeutic tools for allergic diseases by controlling ILC2 function.
|
|
| 4. |
- Maric, Jovana, et al.
(författare)
-
Prostaglandin E-2 suppresses human group 2 innate lymphoid cell function
- 2018
-
Ingår i: Journal of Allergy and Clinical Immunology. - : MOSBY-ELSEVIER. - 0091-6749 .- 1097-6825. ; 141:5, s. 1761-1773.e6
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Group 2 innate lymphoid cells (ILC2s) are involved in the initial phase of type 2 inflammation and can amplify allergic immune responses by orchestrating other type 2 immune cells. Prostaglandin (PG) E-2 is a bioactive lipid that plays protective roles in the lung, particularly during allergic inflammation.Objective: We set out to investigate how PGE(2) regulates human ILC2 function.Methods: The effects of PGE(2) on human ILC2 proliferation and intracellular cytokine and transcription factor expression were assessed by means of flow cytometry. Cytokine production was measured by using ELISA, and real-time quantitative PCR was performed to detect PGE(2) receptor expression.Results: PGE(2) inhibited GATA-3 expression, as well as production of the type 2 cytokines IL-5 and IL-13, from human tonsillar and blood ILC2s in response to stimulation with a combination of IL-25, IL-33, thymic stromal lymphopoietin, and IL-2. Furthermore, PGE(2) downregulated the expression of IL-2 receptor alpha (CD25). In line with this observation, PGE(2) decreased ILC2 proliferation. These effects were mediated by the combined action of E-type prostanoid receptor (EP) 2 and EP4 receptors, which were specifically expressed on ILC2s.Conclusion: Our findings reveal that PGE(2) limits ILC2 activation and propose that selective EP2 and EP4 receptor agonists might serve as a promising therapeutic approach in treating allergic diseases by suppressing ILC2 function.
|
|
| 5. |
- Mazzurana, Luca, et al.
(författare)
-
Crohn's Disease Is Associated With Activation of Circulating Innate Lymphoid Cells
- 2021
-
Ingår i: Inflammatory Bowel Diseases. - : Lippincott-Raven Publishers. - 1078-0998 .- 1536-4844. ; 27:7, s. 1128-1138
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Inflammatory bowel disease (IBD) is associated with disturbed mucosal innate lymphoid cell (ILC) composition, which is correlated to the degree of intestinal inflammation. However, it remains unclear whether circulating ILCs are dysregulated in patients with IBD.METHODS: Blood samples from 53 patients with Crohn's disease (CD), 43 patients with ulcerative colitis (UC), and 45 healthy control subjects (HC) were analyzed by flow cytometry for markers of ILC subsets (ILC1, ILC2, and ILC precursors [ILCp]) and selected IBD-relevant proteins, as predicted by previous genome-wide association studies. A dimensionality reduction approach to analyzing the data was used to characterize circulating ILCs.RESULTS: The frequency of ILCp expressing the ILC3 activation markers NKp44 and CD56 was increased in CD versus HC and UC (NKp44) or in CD versus HC (CD56), whereas the CD45RA+ ILCp were reduced in CD versus UC. Furthermore, the activation marker HLA-DR was increased on ILC1 and ILC2 in CD versus HC. Interestingly, the IBD-related protein SLAMF1 was upregulated on ILC2 from both CD and UC samples as compared with HC samples. In active CD, SLAMF1+ ILC2 frequency was negatively correlated with disease severity (Harvey-Bradshaw index). The characterization of SLAMF1+ ILC2 revealed a higher expression of the ILC2 markers CRTH2, CD161, and GATA3 as compared with SLAMF1- ILC2.CONCLUSIONS: In line with the systemic nature of CD inflammation, our findings point toward the activation of ILCs in the blood of patients with CD. Furthermore, in active CD, circulating SLAMF1+ ILC2 are increased in patients with less active disease, introducing SLAMF1+ ILC2 as interesting therapeutic targets deserving further exploration.
|
|
| 6. |
- Mazzurana, Luca
(författare)
-
Innate lymphoid cell plasticity and heterogeneity in human tissues
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The human immune system is a vital mechanism that protects the host from outside threats. The two main branches of this system, consisting of innate and adaptive immunity, aid the host when dangers of both imminent and protracted nature occur. Innate lymphoid cells (ILC) play a key role in innate immunity and are classified into distinct groups based on their function, transcriptional profile and development. Their discovery is young, with much research needed to understand all aspects of their phenotype, genotype, behavior in homeostasis and disease. This thesis describes the breakthroughs my collaborators and I were able to reach during my five years of doctoral studies, in order to better understand the biology and physiology of ILC. In the first part of this thesis I describe the history and classification of ILC, the efforts being done so far by the field to understand their development, and the possible combinations of changes in ILC status, known as plasticity or trans-differentiation properties of ILC under particular environments or stimuli. As Paper II’s results are based on a cohort of Inflammatory Bowel Disease (IBD) samples, and in Paper I we analyze ILC in intestinal biopsies from IBD patients, I also outline the main characteristics representing this disorder while focusing on the role of ILC in IBD. Next, after defining the aim of my studies, I describe how the data was obtained, as a big part of my work consisted in learning how to handle methods and technologies such as flow cytometry, fluorescence-activated cell sorting (FACS) and single cell RNA sequencing, among others. Finally, a discussion of the results is aimed at highlighting the major breakthroughs achieved. In Paper I, we set out to better understand the function of the Ikaros family of transcription factors in ILC, focusing our efforts on IKZF3 (encoding Aiolos) and its role in ILC trans- differentiation via a drug-induced silencing approach with the immune-modulatory agent lenalidomide. In Paper II, a large cohort of IBD samples was analyzed in order to find disturbances in peripheral blood ILC protein expression. We were able to uncover differences in several activation proteins in the IBD cohort, when compared to a like-sized cohort of samples from healthy controls. In Paper III, a big effort was put into implementing Smart- seq2 RNA sequencing technology to a large number of ILC from a variety of tissues. This allowed us to better understand the heterogeneity of ILC in the circulation, secondary lymphoid and mucosal tissues. We generated a large dataset that will require time to be exploited in full, constituting a roadmap for future studies aimed at understanding human ILC biology and function. In summary, the work presented in this thesis provides findings and datasets that have the potential to advance the ILC field.
|
|
| 7. |
- Mazzurana, Luca, et al.
(författare)
-
Suppression of Aiolos and Ikaros expression by lenalidomide reduces human ILC3−ILC1/NK cell transdifferentiation
- 2019
-
Ingår i: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 202:1
-
Tidskriftsartikel (refereegranskat)abstract
- The Ikaros family of transcription factors (TFs) are important regulators of lymphocyte function. However, their roles in human innate lymphoid cell (ILC) function remain unclear. Here, we found that Ikaros (IKZF1) is expressed by all ILC subsets, including NK cells, in blood, tonsil, and gut, while Helios (IKZF2) is preferentially expressed by ILC3 in tonsil and gut. Aiolos (IKZF3) followed the expression pattern of T-bet and Eomes, being predominantly expressed by ILC1 and NK cells. Differentiation of IFN-γ-producing ILC1 and NK cells from ILC3 by IL-1β plus IL-12-stimulation was associated with upregulation of T-bet and Aiolos. Selective degradation of Aiolos and Ikaros by lenalidomide suppressed ILC1 and NK cell differentiation and expression of ILC1 and NK cell-related transcripts (LEF1, PRF1, GRZB, CD244, NCR3, and IRF8). In line with reduced ILC1/NK cell differentiation, we observed an increase in the expression of the ILC3-related TF Helios, as well as ILC3 transcripts (TNFSF13B, IL22, NRP1, and RORC) and in the frequency of IL-22 producing ILC3 in cultures with IL-1β and IL-23. These data suggest that suppression of Aiolos and Ikaros expression inhibits ILC1 and NK cell differentiation while ILC3 function is maintained. Hence, our results open up for new possibilities in targeting Ikaros family TFs for modulation of type 1/3 immunity in inflammation and cancer.
|
|
| 8. |
- Mazzurana, Luca, et al.
(författare)
-
Tissue-specific transcriptional imprinting and heterogeneity in human innate lymphoid cells revealed by full-length single-cell RNA-sequencing
- 2021
-
Ingår i: Cell Research. - : Springer Science and Business Media LLC. - 1748-7838 .- 1001-0602. ; 31:5, s. 554-568
-
Tidskriftsartikel (refereegranskat)abstract
- The impact of the microenvironment on innate lymphoid cell (ILC)-mediated immunity in humans remains largely unknown. Here we used full-length Smart-seq2 single-cell RNA-sequencing to unravel tissue-specific transcriptional profiles and heterogeneity of CD127+ ILCs across four human tissues. Correlation analysis identified gene modules characterizing the migratory properties of tonsil and blood ILCs, and signatures of tissue-residency, activation and modified metabolism in colon and lung ILCs. Trajectory analysis revealed potential differentiation pathways from circulating and tissue-resident naïve ILCs to a spectrum of mature ILC subsets. In the lung we identified both CRTH2+ and CRTH2− ILC2 with lung-specific signatures, which could be recapitulated by alarmin-exposure of circulating ILC2. Finally, we describe unique TCR-V(D)J-rearrangement patterns of blood ILC1-like cells, revealing a subset of potentially immature ILCs with TCR-δ rearrangement. Our study provides a useful resource for in-depth understanding of ILC-mediated immunity in humans, with implications for disease.
|
|
| 9. |
|
|
| 10. |
- Niessl, Julia, et al.
(författare)
-
Identification of resident memory CD8+ T cells with functional specificity for SARS-CoV-2 in unexposed oropharyngeal lymphoid tissue
- 2021
-
Ingår i: Science immunology. - : American Association for the Advancement of Science (AAAS). - 2470-9468. ; 6:64
-
Tidskriftsartikel (refereegranskat)abstract
- Cross-reactive CD4+ T cells that recognize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more commonly detected in the peripheral blood of unexposed individuals compared with SARS-CoV-2–reactive CD8+ T cells. However, large numbers of memory CD8+ T cells reside in tissues, feasibly harboring localized SARS-CoV-2–specific immune responses. To test this idea, we performed a comprehensive functional and phenotypic analysis of virus-specific T cells in tonsils, a major lymphoid tissue site in the upper respiratory tract, and matched peripheral blood samples obtained from children and adults before the emergence of COVID-19 (coronavirus disease 2019). We found that SARS-CoV-2–specific memory CD4+ T cells could be found at similar frequencies in the tonsils and peripheral blood in unexposed individuals, whereas functional SARS-CoV-2–specific memory CD8+ T cells were almost only detectable in the tonsils. Tonsillar SARS-CoV-2–specific memory CD8+ T cells displayed a follicular homing and tissue-resident memory phenotype, similar to tonsillar Epstein-Barr virus–specific memory CD8+ T cells, but were functionally less potent than other virus-specific memory CD8+ T cell responses. The presence of preexisting tissue-resident memory CD8+ T cells in unexposed individuals could potentially enable rapid sentinel immune responses against SARS-CoV-2.
|
|
