TY - JOUR A1 - Wagner-Drouet, Eva A1 - Teschner, Daniel A1 - Wolschke, Christine A1 - Schäfer-Eckart, Kerstin A1 - Gärtner, Johannes A1 - Mielke, Stephan A1 - Schreder, Martin A1 - Kobbe, Guido A1 - Hilgendorf, Inken A1 - Klein, Stefan A1 - Verbeek, Mareike A1 - Ditschkowski, Markus A1 - Koch, Martina A1 - Lindemann, Monika A1 - Schmidt, Traudel A1 - Rascle, Anne A1 - Barabas, Sascha A1 - Deml, Ludwig A1 - Wagner, Ralf A1 - Wolff, Daniel T1 - Comparison of cytomegalovirus-specific immune cell response to proteins versus peptides using an IFN-γ ELISpot assay after hematopoietic stem cell transplantation JF - Diagnostics N2 - Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality following hematopoietic stem cell transplantation (HSCT). Measuring CMV-specific cellular immunity may improve the risk stratification and management of patients. IFN-γ ELISpot assays, based on the stimulation of peripheral blood mononuclear cells with CMV pp65 and IE-1 proteins or peptides, have been validated in clinical settings. However, it remains unclear to which extend the T-cell response to synthetic peptides reflect that mediated by full-length proteins processed by antigen-presenting cells. We compared the stimulating ability of pp65 and IE-1 proteins and corresponding overlapping peptides in 16 HSCT recipients using a standardized IFN-γ ELISpot assay. Paired qualitative test results showed an overall 74.4% concordance. Discordant results were mainly due to low-response tests, with one exception. One patient with early CMV reactivation and graft-versus-host disease, sustained CMV DNAemia and high CD8\(^+\) counts showed successive negative protein-based ELISpot results but a high and sustained response to IE-1 peptides. Our results suggest that the response to exogenous proteins, which involves their uptake and processing by antigen-presenting cells, more closely reflects the physiological response to CMV infection, while the response to exogenous peptides may lead to artificial in vitro T-cell responses, especially in strongly immunosuppressed patients. KW - CMV KW - CMV-specific cellular immunity KW - hematopoietic stem cell transplantation KW - recall antigen KW - peptide KW - immune monitoring KW - IFN-γ ELISpot KW - T cells KW - antigen processing and presentation KW - immunosuppression Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228843 SN - 2075-4418 VL - 11 IS - 2 ER - TY - JOUR A1 - Kader, Hidaya A. A1 - Azeem, Muhammad A1 - Jwayed, Suhib A. A1 - Al-Shehhi, Aaesha A1 - Tabassum, Attia A1 - Ayoub, Mohammed Akli A1 - Hetta, Helal F. A1 - Waheed, Yasir A1 - Iratni, Rabah A1 - Al-Dhaheri, Ahmed A1 - Muhammad, Khalid T1 - Current insights into immunology and novel therapeutics of atopic dermatitis JF - Cells N2 - Atopic dermatitis (AD) is one of the most prevalent inflammatory disease among non-fatal skin diseases, affecting up to one fifth of the population in developed countries. AD is characterized by recurrent pruritic and localized eczema with seasonal fluctuations. AD initializes the phenomenon of atopic march, during which infant AD patients are predisposed to progressive secondary allergies such as allergic rhinitis, asthma, and food allergies. The pathophysiology of AD is complex; onset of the disease is caused by several factors, including strong genetic predisposition, disrupted epidermal barrier, and immune dysregulation. AD was initially characterized by defects in the innate immune system and a vigorous skewed adaptive Th2 response to environmental agents; there are compelling evidences that the disorder involves multiple immune pathways. Symptomatic palliative treatment is the only strategy to manage the disease and restore skin integrity. Researchers are trying to more precisely define the contribution of different AD genotypes and elucidate the role of various immune axes. In this review, we have summarized the current knowledge about the roles of innate and adaptive immune responsive cells in AD. In addition, current and novel treatment strategies for the management of AD are comprehensively described, including some ongoing clinical trials and promising therapeutic agents. This information will provide an asset towards identifying personalized targets for better therapeutic outcomes. KW - atopic dermatitis KW - immune system KW - T cells KW - B cells KW - keratinocytes Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241008 SN - 2073-4409 VL - 10 IS - 6 ER - TY - JOUR A1 - Thomann, Anna Sophie A1 - Schneider, Theresa A1 - Cyran, Laura A1 - Eckert, Ina Nathalie A1 - Kerstan, Andreas A1 - Lutz, Manfred B. T1 - Conversion of Anergic T Cells Into Foxp3\(^-\) IL-10\(^+\) Regulatory T Cells by a Second Antigen Stimulus In Vivo JF - Frontiers in Immunology N2 - T cell anergy is a common mechanism of T cell tolerance. However, although anergic T cells are retained for longer time periods in their hosts, they remain functionally passive. Here, we describe the induction of anergic CD4\(^+\) T cells in vivo by intravenous application of high doses of antigen and their subsequent conversion into suppressive Foxp3\(^-\) IL-10\(^+\) Tr1 cells but not Foxp3\(^+\) Tregs. We describe the kinetics of up-regulation of several memory-, anergy- and suppression-related markers such as CD44, CD73, FR4, CD25, CD28, PD-1, Egr-2, Foxp3 and CTLA-4 in this process. The conversion into suppressive Tr1 cells correlates with the transient intracellular CTLA-4 expression and required the restimulation of anergic cells in a short-term time window. Restimulation after longer time periods, when CTLA-4 is down-regulated again retains the anergic state but does not lead to the induction of suppressor function. Our data require further functional investigations but at this stage may suggest a role for anergic T cells as a circulating pool of passive cells that may be re-activated into Tr1 cells upon short-term restimulation with high and systemic doses of antigen. It is tentative to speculate that such a scenario may represent cases of allergen responses in non-allergic individuals. KW - T cells KW - anergy KW - Tr1 KW - conversion KW - in vivo Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241429 SN - 1664-3224 VL - 12 ER - TY - JOUR A1 - Romero‐Olmedo, Addi J. A1 - Schulz, Axel R. A1 - Huber, Magdalena A1 - Brehm, Corinna U. A1 - Chang, Hyun‐Dong A1 - Chiarolla, Cristina M. A1 - Bopp, Tobias A1 - Skevaki, Chrysanthi A1 - Berberich‐Siebelt, Friederike A1 - Radbruch, Andreas A1 - Mei, Henrik E. A1 - Lohoff, Michael T1 - Deep phenotypical characterization of human CD3\(^{+}\)CD56\(^{+}\) T cells by mass cytometry JF - European Journal of Immunology N2 - CD56\(^{+}\) T cells are a group of pro‐inflammatory CD3\(^{+}\) lymphocytes with characteristics of natural killer cells, being involved in antimicrobial immune defense. Here, we performed deep phenotypic profiling of CD3\(^{+}\)CD56\(^{+}\) cells in peripheral blood of normal human donors and individuals sensitized to birch‐pollen or/and house dust mite by high‐dimensional mass cytometry combined with manual and computational data analysis. A co‐regulation between major conventional T‐cell subsets and their respective CD3\(^{+}\)CD56\(^{+}\) cell counterparts appeared restricted to CD8\(^{+}\), MAIT, and TCRγδ\(^{+}\) T‐cell compartments. Interestingly, we find a co‐regulation of several CD3\(^{+}\)CD56\(^{+}\) cell subsets in allergic but not in healthy individuals. Moreover, using FlowSOM, we distinguished a variety of CD56\(^{+}\) T‐cell phenotypes demonstrating a hitherto underestimated heterogeneity among these cells. The novel CD3\(^{+}\)CD56\(^{+}\) subset description comprises phenotypes superimposed with naive, memory, type 1, 2, and 17 differentiation stages, in part represented by a phenotypical continuum. Frequencies of two out of 19 CD3\(^{+}\)CD56\(^{+}\) FlowSOM clusters were significantly diminished in allergic individuals, demonstrating less frequent presence of cells with cytolytic, presumably protective, capacity in these donors consistent with defective expansion or their recruitment to the affected tissue. Our results contribute to defining specific cell populations to be targeted during therapy for allergic conditions. KW - allergy KW - CD56 KW - human KW - mass cytometry KW - T cells Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225699 VL - 51 IS - 3 SP - 672 EP - 681 ER - TY - JOUR A1 - Eckert, Ina N. A1 - Ribechini, Eliana A1 - Jarick, Katja J. A1 - Strozniak, Sandra A1 - Potter, Sarah J. A1 - Beilhack, Andreas A1 - Lutz, Manfred B. T1 - VLA-1 Binding to Collagen IV Controls Effector T Cell Suppression by Myeloid-Derived Suppressor Cells in the Splenic Red Pulp JF - Frontiers in Immunology N2 - Myeloid-derived suppressor cells (MDSCs) represent a major population controlling T cell immune responses. However, little is known about their molecular requirements for homing and T cell interaction to mediate suppression. Here, we investigated the functional role of the homing and collagen IV receptor VLA-1 (α1β1-integrin) on in vitro GM-CSF generated murine MDSCs from wild-type (WT) and CD49a/α1-integrin (Itga1\(^{−/−}\)) gene-deficient mice. Here, we found that effector (Teff) but not naive (Tn) CD4\(^+\) T cells express VLA-1 and monocytes further up-regulated their expression after culture in GM-CSF when they differentiated into the monocytic subset of resting MDSCs (R-MDSCs). Subsequent activation of R-MDSCs by LPS+IFN-γ (A-MDSCs) showed increased in vitro suppressor potential, which was independent of VLA-1. Surprisingly, VLA-1 deficiency did not influence A-MDSC motility or migration on collagen IV in vitro. However, interaction times of Itga1\(^{−/−}\) A-MDSCs with Teff were shorter than with WT A-MDSCs on collagen IV but not on fibronectin substrate in vitro. After injection, A-MDSCs homed to the splenic red pulp where they co-localized with Teff and showed immediate suppression already after 6 h as shown by inhibition of T cell proliferation and induction of apoptosis. Injection of A-MDSCs from Itga1\(^{−/−}\) mice showed equivalent homing into the spleen but a reduced suppressive effect. Interaction studies of A-MDSCs with Teff in the subcapsular red pulp with intravital two-photon microscopy revealed also here that MDSC motility and migration parameters were not altered by VLA-1 deficiency, but the interaction times with Teff were reduced. Together, our data point to a new role of VLA-1 adhesion to collagen IV as a prerequisite for extended contact times with Teff required for suppression. KW - myeloid-derived suppressor cells (MDSCs) KW - T cells KW - VLA-1 KW - homing KW - spleen Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222671 SN - 1664-3224 VL - 11 ER -