Variable EBV DNA load distributions and heterogeneous EBV mRNA expression patterns in the circulation of solid organ versus stem cell transplant recipients

Epstein-Barr virus (EBV) driven post-transplant lymphoproliferative disease (PTLD) is a heterogeneous and potentially life-threatening condition. Early identification of aberrant EBV activity may prevent progression to B-cell lymphoma. We measured EBV DNA load and RNA profiles in plasma and cellular blood compartments of stem cell transplant (SCT; n = 5), solid organ transplant recipients (SOT; n = 15), and SOT having chronic elevated EBV-DNA load (n = 12). In SCT, EBV DNA was heterogeneously distributed, either in plasma or leukocytes or both. In SOT, EBV DNA load was always cell associated, predominantly in B cells, but occasionally in T cells (CD4 and CD8) or monocytes. All SCT with cell-associated EBV DNA showed BARTs an

No Evidence for Circulating Retina Specific Autoreactive T-cells in Latent Tuberculosis-associated Uveitis and Sarcoid Uveitis

Purpose: To detect circulating retina-specific autoreactive CD4+ T-cells and antiretinal antibodies (ARA) in latent tuberculosis (TB)-associated uveitis or sarcoid uveitis patients. Methods: The presence of crude retinal extract (RE) autoreactive CD4+ T-cells was determined by a highly sensitive flowcytometric-based technique examining co-expression of CD25 and CD134 (OX40) on RE stimulated PBMC. The presence of ARA in available matched serum samples was assessed by indirect immunofluorescence. Results: No autoreactive CD4+ T-cells against RE could be detected in either latent TB-associated uveitis or sarcoid uveitis patients, while ARA were detected in the serum of the majority (5/6) of latent TB-associated uveitis and all (3/3) sarcoid uveitis patients. Conclusion: Even with the use of this highly sensitive flowcytometric technique circulating retina-specific autoreactive CD4+ T-cells could not be detected. In contrast, ARA were detected in the majority of patients indicating an adaptive humoral immune response toward retinal antigens had occurred

Immunophenotypic measurable residual disease (MRD) in acute myeloid leukemia: Is multicentric MRD assessment feasible?

Flow-cytometric detection of now termed measurable residual disease (MRD) in acute myeloid leukemia (AML) has proven to have an independent prognostic impact. In a previous multicenter study we developed protocols to accurately define leukemia-associated immunophenotypes (LAIPs) at diagnosis. It has, however, not been demonstrated whether the use of the defined LAIPs in the same multicenter setting results in a high concordance between centers in MRD assessment. In the present paper we evaluated whether interpretation of list-mode data (LMD) files, obtained from MRD assessment of previously determined LAIPs during and after treatment, could reliably be performed in a multicenter setting. The percentage of MRD positive cells was simultaneously determined in totally 173 LMD files from 77 AML patients by six participating centers. The quantitative concordance between the six participating centers was meanly 84%, with slight variation of 75%–89%. In addition our data showed that the type and number of LAIPs were of influence on the performance outcome. The highest concordance was observed for LAIPs with cross-lineage expression, followed by LAIPs with an asynchronous antigen expression. Our results imply that immunophenotypic MRD assessment in AML will only be feasible when fully standardized methods are used for reliable multicenter assessment

Diagnostiek bij multipel myeloom: de rol van beeldvorming, chromosomenanalyse en multiparameterflowcytometrie.

Contains fulltext : 97814.pdf (publisher's version ) (Open Access

Analytical performance of a standardized single-platform MHC tetramer assay for the identification and enumeration of CMV-specific CD8+ T lymphocytes

Major histocompatibility complex (MHC) multimers that identify antigen-specific T cells, coupled with flow cytometry, have made a major impact on immunological research. HLA Class I multimers detect T cells directed against viral, tumor, and transplantation antigens with exquisite sensitivity. This technique has become an important standard for the quantification of a T cell immune response. The utility of this method in multicenter studies, however, is dependant on reproducibility between laboratories. As part of a clinical study using a standardized two-tube three-color single-platform method, we monitored and characterized performance across multiple sites using tetramers against the T cell receptors (TCR) specific for MHC Class I, A*0101 - VTEHDTLLY, A*0201 - NLVPMVATV and B*0702 - TPRVTGGGAM CMV peptides. We studied the analytical performance of this method, focusing on reducing background, maximizing signal intensity, and ensuring that sufficient cells are enumerated to provide meaningful statistics. Inter and intra-assay performance were assessed, which included inherent variability introduced by shipping, type of flow cytometer used, protocol adherence, and analytical interpretation across a range of multiple sample levels and specificities under routine laboratory testing conditions. Using the described protocol, it is possible to obtain intra- and interlab CV's of <20%, with a functional sensitivity for absolute tetramer counts of 1 cell/μL and 0.2% tetramer+ percent for A*0101, A*0201, and B*0702 alleles. The standardized single-platform MHC tetramer assay is simple, rapid, reproducible, and useful for assessing CMV-specific T cells, and will allow for reasonable comparisons of clinical evaluations across multiple centers at clinically relevant thresholds (2.0-10.0 cells/μL)

Fifteen Years of External Quality Assessment in Leukemia/Lymphoma Immunophenotyping in The Netherlands and Belgium: A Way Forward

Immunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease

Defining consensus leukemia-associated immunophenotypes for detection of minimal residual disease in acute myeloid leukemia in a multicenter setting.

Flow-cytometric detection of minimal residual disease (MRD) has proven in several single-institute studies to have an independent prognostic impact. We studied whether this relatively complex approach could be performed in a multicenter clinical setting. Five centers developed common protocols to accurately define leukemia-associated (immuno)phenotypes (LAPs) at diagnosis required to establish MRD during/after treatment. List mode data files were exchanged, and LAPs were designed by each center. One center, with extensive MRD experience, served as the reference center and coordinator. In quarterly meetings, consensus LAPs were defined, with the performance of centers compared with these. In a learning (29 patients) and a test phase (35 patients), a mean of 2.2 aberrancies/patient was detected, and only 1/63 patients (1.6%) had no consensus LAP(s). For the four centers without (extensive) MRD experience, clear improvement could be shown: in the learning phase, 39-63% of all consensus LAPs were missed, resulting in a median 30% of patients (range 21-33%) for whom no consensus LAP was reported; in the test phase, 27-40% missed consensus LAPs, resulting in a median 16% (range 7-18%) of 'missed' patients. The quality of LAPs was extensively described. Immunophenotypic MRD assessment in its current setting needs extensive experience and should be limited to experienced centers

Apparition (Piece 2)

Apparition is made from watercolor over aquatint. Artist\u27s Statement As an artist and an art historical scholar, I constantly struggle with how these endeavors overlap and influence each other. My work as a painter-printmaker seeks to use the expressionist figure to express my persistent anxiety as well as comment on shared human experiences; yet as a scholar, my interests lie in the decorative and graphic arts. My current work came with a desire to reconcile and combine the two seemingly divergent interests through a fusion of images and diverse techniques to give them form. Upon the culmination of this series, I have reached a place where i have realized that these two spheres of myself do not - and never have - dwelt in vacuums and, as such, I am constantly thinking and working as both a scholar and artist.https://digitalcommons.linfield.edu/avc_thesis2016/1013/thumbnail.jp