16 research outputs found
The simultaneous isolation of multiple high and low frequent T-cell populations from donor peripheral blood mononuclear cells using the major histocompatibility complex I-Streptamer isolation technology
No full textImmunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease
Kwalitatief interviewen, kunst en kunde
No full textHet kwalitatieve interview heeft veel weg van een goed gesprek. Wat maakt iemand tot een goede gesprekspartner? Dat hij luistert met aandacht, meedenkt en meevoelt met het vertelde en je uit laat spreken. Kortom: een invoelende ruimte biedt en belangstellend is. Is zo iemand vanzelf een goede interviewer? Nee, want alhoewel hiermee de basis is gelegd voor een deel van de kunst waar de titel van dit boek naar verwijst, heeft een interviewer additionele kennis en vaardigheden nodig. Dat is de kunde, die in dit boek uitgebreid besproken wordt. Een interview is allereerst een vraaggesprek met een welbepaald informatiedoel. En pas als de vaardigheden van de goede gesprekspartner samenkomen met de kunde van de onderzoeker, is er sprake van de interviewkunst waar in de titel naar verwezen wordt. In deel I van het boek (geschreven door Jeanine Evers en Fijgje de Bo er) worden uitgebreid allerlei technische kwesties van het interviewen besproken in samenhang met het improviserende karakter van een goed kwalitatief interview. In deel II wordt door auteurs met verschillende disciplinaire achtergronden gesproken over het interviewen van specifieke groepen respondenten (Nico Baakman over elites, Hans Krober en Jeroen Zomerplaag over verstandelijk gehandicapten, Jacomine de Lange over ouderen, Ilse van Liempt over gesmokkelde migranten) en over bepaald soort interviews (Ad van Fessem over focusgroepen in marktonderzoek, Frank van Gemert over interviews bij etnografisch veldwerk, Ellis Jonker over biografische interviews, Ilja Maso over hermeneutische interviews en Stef Scagliola over oral history interviews bij (ex-)militairen. Dit boek is geschikt voor elke onderzoeker die kwalitatieve interviews wil gaan toepassen, alsmede voor onderwijs in kwalitatief interviewen
Assessing the daily stability of the cortisol awakening response in a controlled environment
No full textBackground
Levels of cortisol, the end product of the hypothalamic-pituitary-adrenal (HPA) axis, display a sharp increase immediately upon awakening, known as the cortisol awakening response (CAR). The daily stability of the CAR is potentially influenced by a range of methodological factors, including light exposure, participant adherence, sleep duration and nocturnal awakenings, making inferences about variations in the CAR difficult. The aim of the present study was to determine the daily stability of multiple measurement indices of the CAR in a highly-controlled sleep laboratory environment. A secondary aim was to examine the association between objective sleep continuity and sleep architecture, and the CAR.
Methods
The CAR was assessed in 15 healthy normal sleepers (seven male, eight female, Mage = 23.67 ± 3.49 years) on three consecutive weekday mornings. Sleep was measured objectively using polysomnography. Saliva samples were obtained at awakening, +15, +30, +45 and +60 min, from which multiple CAR measurement indices were derived: cortisol levels at each time point, awakening cortisol levels, the mean increase in cortisol levels (MnInc) and total cortisol secretion during the measurement period. Morning 2 and Morning 3 awakening cortisol levels, MnInc and total cortisol secretion were compared and the relationship between Night 1 and Night 2 objective measures of sleep continuity and architecture, and the subsequent CAR, was also assessed.
Results
There were no differences in cortisol levels at each time point, or total cortisol secretion during the CAR period, between Morning 2 and Morning 3. Awakening cortisol levels were lower, and the MnInc was higher, on Morning 3. Morning 2 and Morning 3 awakening levels (r = 0.77) and total cortisol secretion (r = 0.82), but not the magnitude of increase, were positively associated.
Conclusions
The stability of the CAR profile and total cortisol secretion, but not awakening cortisol levels or the magnitude of increase, was demonstrated across two consecutive mornings of measurement in a highly-controlled environment. Awakening cortisol levels, and the magnitude of increase, may be sensitive to differences in daily activities
Differential regulation of C-type lectin expression on tolerogenic dendritic cell subsets
No full textAntigen presenting cells (APC) express high levels of C-type lectins, which play a major role in cellular interactions as well as pathogen recognition and antigen presentation. The C-type lectin macrophage galactose-type lectin (MGL), expressed by dendritic cells (DC) and macrophages, mediates binding to glycoproteins and lipids that contain terminal GalNAc moieties. To investigate MGL expression patterns in more detail, we generated two new monoclonal antibodies and set up a quantitative real-time PCR analysis to determine MGL mRNA levels. MGL is not expressed by blood-resident plasmacytoid DC and thus represents an exclusive marker for myeloid-type APC. Dexamethasone treatment upregulated MGL expression on DC both at the protein and mRNA level in a time- and dose-dependent manner. In contrast, DC generated in the presence of IL-10 did not display enhanced MGL levels. Furthermore, dexamethasone and IL-10 also differentially regulated expression of other C-type lectins, such as DC-SIGN and Mannose Receptor. Our results demonstrate that depending on the local microenvironment, DC can adopt different C-type lectin profiles, which could have major influences on cell-cell interactions, antigen uptake and presentatio
DC-SIGN mediates binding of dendritic cells to authentic pseudo-LewisY glycolipids of Schistosoma mansoni cercariae, the first parasite-specific ligand of DC-SIGN
No full textInternational audienc
A Good Manufacturing Practice procedure to engineer donor virus-specific T cells into potent anti-leukemic effector cells
No full textClinical Pharmacy and Toxicolog
Schistosoma mansoni soluble egg antigens are internalized by human dendritic cells through multiple C-type lectins and suppress TLR-induced dendritic cell activation
No full textIn schistosomiasis, a parasitic disease caused by helminths, the parasite eggs induce a T helper 2 cell (T(H)2) response in the host. Here, the specific role of human monocyte-derived dendritic cells (DCs) in initiation and polarization of the egg-specific T cell responses was examined. We demonstrate that immature DCs (iDCs) pulsed with schistosome soluble egg antigens (SEA) do not show an increase in expression of co-stimulatory molecules or cytokines, indicating that no conventional maturation was induced. The ability of SEA to affect the Toll-like receptor (TLR) induced maturation of iDCs was examined by copulsing the DCs with SEA and TLR-ligands. SEA suppressed both the maturation of iDCs induced by poly-I:C and LPS, as indicated by a decrease in co-stimulatory molecule expression and production of IL-12, IL-6 and TNF-alpha. In addition, SEA suppressed T(H)1 responses induced by the poly-I:C-pulsed DCs, and skewed the LPS-induced mixed response towards a T(H)2 response. Immature DCs rapidly internalized SEA through the C-type lectins DC-SIGN, MGL and the mannose receptor and the antigens were targeted to MHC class II-positive lysosomal compartments. The internalization of SEA by multiple C-type lectins may be important to regulate the response of the iDCs to TLR-induced signals
Simultaneous Isolation of CD8(+) and CD4(+) T Cells Specific for Multiple Viruses for Broad Antiviral Immune Reconstitution After Allogeneic Stem Cell Transplantation
No full textOpportunistic viral infections can cause serious morbidity and mortality in immunocompromised patients after allogeneic stem cell transplantation. Clinical studies have shown that adoptive transfer of donor-derived T cells specific for cytomegalovirus (CMV), Epstein-Barr virus (EBV), or human adenovirus (HAdV) can be a safe and effective treatment of infections with these major viral pathogens. The aim of this study was to develop a method for the simultaneous isolation of coordinated CD8(+) and CD4(+) memory T-cell responses against a broad repertoire of viral epitopes. To ensure that the method was applicable to a wide variety of virus-specific T cells that may differ in phenotypic and functional properties, we focused on T cells specific for the persistent viruses, CMV and EBV, and T cells specific for HAdV and influenza (FLU), which are not repetitively activated in vivo after initial viral clearance. Following in vitro activation, nearly all T cells specific for these viruses produced interferon gamma (IFN-gamma) and tumor necrosis factor a, and expressed CD137, whereas the populations varied in the production of interleukin-2, degranulation, and expression of phenotypic markers. Different kinetics of IFN-g production were observed in CMV/EBV-specific T cells and HAdV/FLU-specific T cells. However, after the stimulation of peripheral blood from seropositive donors with viral protein-spanning peptide pools, the activated virus-specific CD8(+) and CD4(+) T cells could be simultaneously isolated by either IFN-gamma-based or CD137-based enrichment. This study provides an efficient and widely applicable strategy for the isolation of virus-specific T cells, which may be used for the reconstitution of virus-specific immunity in allogeneic stem cell transplantation recipients.Immunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease
Molecular basis of the differences in binding properties of the highly related C-type lectins DC-SIGN and L-SIGN to Lewis X trisaccharide and Schistosoma mansoni egg antigens.
No full textThe dendritic cell-specific C-type lectin DC-SIGN functions as a pathogen receptor that recognizes Schistosoma mansoni egg antigens through its major glycan epitope Galbeta1,4(Fucalpha1,3)GlcNAc (Lex). Here we report that L-SIGN, a highly related homologue of DC-SIGN found on liver sinusoidal endothelial cells, binds to S. mansoni egg antigens but not to the Lex epitope. L-SIGN does bind the Lewis antigens Lea, Leb, and Ley, similar as DC-SIGN. A specific mutation in the carbohydrate recognition domain of DC-SIGN (V351G) abrogates binding to all Lewis antigens. In L-SIGN Ser363 is present at the corresponding position of Val351 in DC-SIGN. Replacement of this Ser into Val resulted in a "gain of function" L-SIGN mutant that binds to Lex, and shows increased binding to the other Lewis antigens. These data indicate that Val351 is important for the fucose specificity of DC-SIGN. Molecular modeling and docking of the different Lewis antigens in the carbohydrate recognition domains of L-SIGN, DC-SIGN, and their mutant forms, demonstrate that Val351 in DC-SIGN creates a hydrophobic pocket that strongly interacts with the Fucalpha1,3/4-GlcNAc moiety of the Lewis antigens. The equivalent amino acid residue Ser363 in L-SIGN creates a hydrophilic pocket that prevents interaction with Fucalpha1,3-GlcNAc in Lex but supports interactions with the Fucalpha1,4-GlcNAc moiety in Lea and Leb antigens. These data demonstrate for the first time that DC-SIGN and L-SIGN differ in their carbohydrate binding profiles and will contribute to our understanding of the functional roles of these C-type lectin receptors, both in recognition of pathogen and self-glycan antigens
