Paris-Trousseau thrombocytopenia is phenocopied by the autosomal recessive inheritance of a DNA-binding domain mutation in FLI1.

Hemizygous deletion of a variable region on chromosome 11q containing FLI1 causes an inherited platelet-related bleeding disorder in Paris-Trousseau thrombocytopenia and Jacobsen syndrome. These multisystem disorders are also characterized by heart anomalies, changes in facial structure, and intellectual disability. We have identified a consanguineous family with autosomal recessive inheritance of a bleeding disorder that mimics Paris-Trousseau thrombocytopenia but has no other features of the 11q23 deletion syndrome. Affected individuals in this family have moderate thrombocytopenia; absent collagen-induced platelet aggregation; and large, fused α-granules in 1% to 5% of circulating platelets. This phenotype was caused by a FLI1 homozygous c.970C>T-point mutation that predicts an arginine-to-tryptophan substitution in the conserved ETS DNA-binding domain of FLI1. This mutation caused a transcription defect at the promoter of known FLI1 target genes GP6, GP9, and ITGA2B, as measured by luciferase assay in HEK293 cells, and decreased the expression of these target proteins in affected members of the family as measured by Western blotting of platelet lysates. This kindred suggests abnormalities in FLI1 as causative of Paris-Trousseau thrombocytopenia and confirms the important role of FLI1 in normal platelet development.

Effects of storage time and temperature on highly multiparametric flow analysis of peripheral blood samples; implications for clinical trial samples.

We sought to determine the effect of time and temperature of blood sample storage before preparation of human peripheral blood mononuclear cells (PBMCs) by Ficoll-hypaque density gradient centrifugation. Blood samples from healthy donors were stored at room temperature (RT) or refrigerated at 4°C before preparation of PBMCs. Cell yield and viability, and proportions of major cell populations within PBMCs, as determined by fluorescence flow cytometry, were assessed for both fresh and cryopreserved samples. Highly multiparametric mass cytometry was performed on cryopreserved PBMCs. We found that refrigeration had marked negative effects on subsequent PBMC yield. Storage at RT led to co-purification of low density neutrophils with PBMCs, but had no detectable effects on the proportions of multiple cell subsets including, but not limited to, monocytes, NK cells, B cells, Treg cells, and naïve, central memory and effector memory CD4+ and CD8+ T cells and CD45RA-positive terminal effector CD8+ T cells. Expression of a number of cell surface receptors, including CXCR5, CCR6, CXCR3 and TIGIT, but not CD247 was reduced after RT storage before PBMC preparation, and this effect correlated with the degree of low density neutrophil contamination. As such, when PBMC preparation cannot be undertaken immediately after blood draw, storage at RT is far superior to refrigeration. RT storage leads to neutrophil activation, but does not compromise measurement of PBMC subset distribution. However caution must be applied to interpretation of cytometric measurements of surface molecules such as chemokine receptors.

Association of umbilical placental vascular disease with fetal acute inflammatory cytokine responses.

OBJECTIVE: We examined the hypothesis that fetal proinflammatory cytokine release is a feature of placental vascular disease causing fetal compromise. We measured the concentrations of fetal proinflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and interleukin-8 (IL-8) in the presence of vascular disease in the umbilical placental villous circulation. Vascular disease was identified by high-resistance umbilical artery Doppler flow velocity waveform studies. METHODS: We measured levels of the inflammatory cytokines IL-6 and TNF-alpha and the chemokine IL-8 in fetal blood. Blood was collected from the umbilical vein at delivery, and serum was stored at -70C until assayed using chemiluminescent and enzyme-linked immunosorbent assay methods. We studied 36 normal pregnancies delivered by elective cesarean at term and 50 pregnancies with a high-resistance umbilical artery Doppler flow velocity waveform pattern indicative of fetal placental vascular disease delivered by elective cesarean because of potential fetal compromise. RESULTS: In the presence of umbilical placental vascular disease there were significantly higher levels of IL-6 (median 5.3 pg/mL, P <.05) and IL-8 (median 26.5 pg/mL, P <.01) compared with normal pregnancies (median value of IL-6 and IL-8 were below assay threshold). There was no difference for TNF-alpha, with the median results undetectable in both groups. CONCLUSION: We found higher concentrations of IL-6 and IL-8 in the fetal circulation in the presence of umbilical placental vascular disease.