👤 Corinne Rolland

Accurate diagnosis of B-cell chronic lymphoproliferative disorders (B-CLPDs) remains challenging due to overlapping phenotypes across subtypes. Machine learning (ML) offers promising tools to improve marker evaluation and refine flow cytometry analysis. We investigated the use of ML algorithms to evaluate the diagnostic value of incorporating CD148, CD180, and CD200 into standard B-CLPD phenotyping panel and to develop a diagnosis decision tree. We trained models with flow cytometry data from 480 patients with B-CLPDs using XGBoost and DecisionTree algorithms. The final models integrated 2 categorical markers (CD5 and CD10) and quantiles of fluorescence intensity of 4 quantitative markers (CD20, CD180, and CD200) to classify 6 B-CLPD subtypes. These trained models were applied to an independent cohort of 433 patients with B-CLPD analyzed on a different flow cytometer platform. DecisionTree models achieved the highest classification accuracy (mean accuracy, 0.88) in the validation cohort. The overall specificity ranged from 0.95 lymphoplasmacytic lymphoma (LPL) to 1 hairy cell leukemia (HCL), whereas sensitivity varied from 0.75 (LPL) to 1 (HCL). The DecisionTree model demonstrated superior identification of chronic lymphocytic leukemia compared to a Matutes score of 4 or 5 (P = .029). In more than half of the cases, a diagnosis was determined with near certainty using only the cytometry data. For the remaining cases, a hierarchical approach incorporating additional tests was proposed. For practical implementation, an interactive interface provides diagnostic predictions, positive predictive values, and Gini index scores. This study establishes a ML-optimized strategy for B-CLPD classification, combining phenotypic, cytogenetic, and molecular data to enhance diagnostic accuracy of leukemic B-CLPD cells. This trial was registered at www.ClinicalTrials.gov as #NCT04952974. Show less

Speech impairment is a recognized but unpredictable adverse effect of sub-thalamic nucleus deep brain stimulation (STN-DBS) for Parkinson's disease (PD). To evaluate the prevalence of speech impairment 1 year after STN-DBS in PD patients and to determine the predictive factors for speech outcome following STN-DBS. Data for 417 patients from the French national PREDISTIM study were collected preoperatively. The combined effect of medical treatment and surgery on speech was compared using specific items from dedicated clinical scales (MDS-UPDRS III.1: primary endpoint) and patient self-assessment questionnaires (items 34 and 35 of the PDQ39: secondary endpoints). For each variable, three patient groups were generated according to speech outcome at 1 year: worsening, stability, and improvement. In the second step analysis, the three groups were compared for demographic and clinical variables at baseline and STN-DBS parameters. There was a significant deterioration in speech of all considered items 1 year after combined STN-DBS and dopaminergic treatment. Four predictive factors for speech deterioration were detected: (i) the absence of preoperative speech impairment (p < 0.001); (ii) severity of motor activity of daily living (MDS-UPDRS II off total score) (p = 0.037); (iii) high-intensity stimulation of the left electrode (i.e., above 3.6 V) (p = 0.046); and (iv) the absence of any change in non-motor experiences of daily life (MDS-UPDRS I total score) (p = 0.048). Speech outcome should be carefully monitored after STN-DBS, especially in PD patients without preoperative speech impairment, with motor difficulties in daily-living activities, and with increased left electrode intensity. ClinicalTrials.gov identifier: NCT02360683. Show less

Shigella flexneri is a human intracellular pathogen responsible for bacillary dysentery (bloody diarrhea). S. flexneri invades colonic epithelial cells and spreads from cell to cell, leading to massive epithelial cell fenestration, a critical determinant of pathogenesis. Cell-to-cell spread relies on actin-based motility, which leads to formation of membrane protrusions, as bacteria project into adjacent cells. Membrane protrusions resolve into intermediate structures termed vacuole-like protrusions (VLPs), which remain attached to the primary infected cell by a membranous tether. The resolution of the membranous tether leads to formation of double-membrane vacuoles (DMVs), from which S. flexneri escapes to gain access to the cytosol of adjacent cells. Here, we identify the class III PI3K family member PIK3C3 as a critical determinant of S. flexneri cell-to-cell spread. Inhibition of PIK3C3 decreased the size of infection foci formed by S. flexneri in HT-29 cells. Tracking experiments using live-fluorescence confocal microscopy showed that PIK3C3 is required for efficient resolution of VLPs into DMVs. PIK3C3-dependent accumulation of PtdIns(3)P at the VLP membrane in adjacent cells correlated with the transient recruitment of the membrane scission machinery component Dynamin 2 at the neck of VLPs at the time of DMV formation. By contrast, Listeria monocytogenes did not form VLPs and protrusions resolved directly into DMVs. However, PIK3C3 was also required for L. monocytogenes dissemination, but at the stage of vacuole escape. Finally, we showed that PIK3C3 inhibition decreased S. flexneri dissemination in the infant rabbit model of shigellosis. We propose a model of Shigella dissemination in which vacuole formation relies on the PIK3C3-dependent accumulation of PtdIns(3)P at the VLP stage of cell-to-cell spread, thereby supporting the resolution of VLPs into DMVs through recruitment of the membrane scission machinery component, DNM2. Show less

Prenatal stress is associated with a high risk of developing adult intestinal pathologies, such as irritable bowel syndrome, chronic inflammation, and cancer. Although epithelial stem cells and progenitors have been implicated in intestinal pathophysiology, how prenatal stress could impact their functions is still unknown. We have investigated the proliferative and differentiation capacities of primitive cells using epithelial crypts isolated from colons of adult male and female mice whose mothers have been stressed during late gestation. Our results show that stem cell/progenitor proliferation and differentiation in vitro are negatively impacted by prenatal stress in male progeny. This is promoted by a reinforcement of the negative proliferative/differentiation control by the protease-activated receptor 2 (PAR2) and the muscarinic receptor 3 (M3), two G protein-coupled receptors present in the crypt. Conversely, prenatal stress does not change in vitro proliferation of colon primitive cells in female progeny. Importantly, this maintenance is associated with a functional switch in the M3 negative control of colonoid growth, becoming proliferative after prenatal stress. In addition, the proliferative role of PAR2 specific to females is maintained under prenatal stress, even though PAR2-targeted stress signals Dusp6 and activated GSK3β are increased, reaching the levels of males. An epithelial serine protease could play a critical role in the activation of the survival kinase GSK3β in colonoids from prenatally stressed female progeny. Altogether, our results show that following prenatal stress, colon primitive cells cope with stress through sexually dimorphic mechanisms that could pave the way to dysregulated crypt regeneration and intestinal pathologies. Show less