HepG2 PMM2-CDG knockout model: A versatile platform for variant and therapeutic evaluation.

Phosphomannomutase 2 deficiency (PMM2-CDG), the most frequent congenital disorder of glycosylation, is an autosomal recessive disease caused by biallelic pathogenic variants in the PMM2 gene. There is no cure for this multisystemic syndrome. Some of the therapeutic approaches that are currently in development include mannose-1-phosphate replacement therapy, drug repurposing, and the use of small chemical molecules to correct folding defects. Preclinical models are needed to evaluate the efficacy of treatments to overcome the high lethality of the available animal model. In addition, the number of variants with unknown significance is increasing in clinical settings. This study presents the generation of a cellular disease model by knocking out the PMM2 gene in the hepatoma HepG2 cell line using CRISPR-Cas9 gene editing. The HepG2 knockout model accurately replicates the PMM2-CDG phenotype, exhibiting a complete absence of PMM2 protein and mRNA, a 90% decrease in PMM enzymatic activity, and altered ICAM-1, LAMP1 and A1AT glycoprotein patterns. The evaluation of PMM2 disease-causing variants validates the model's utility for studying new PMM2 clinical variants, providing insights for diagnosis and potentially for evaluating therapies. A CRISPR-Cas9-generated HepG2 knockout model accurately recapitulates the PMM2-CDG phenotype, providing a valuable tool for assessing disease-causing variants and advancing therapeutic strategies.

Transcriptomic analysis identifies dysregulated pathways and therapeutic targets in PMM2-CDG.

PMM2-CDG (MIM # 212065), the most common congenital disorder of glycosylation, is caused by the deficiency of phosphomannomutase 2 (PMM2). It is a multisystemic disease of variable severity that particularly affects the nervous system; however, its molecular pathophysiology remains poorly understood. Currently, there is no effective treatment. We performed an RNA-seq based transcriptomic study using patient-derived fibroblasts to gain insight into the mechanisms underlying the clinical symptomatology and to identify druggable targets. Systems biology methods were used to identify cellular pathways potentially affected by PMM2 deficiency, including Senescence, Bone regulation, Cell adhesion and Extracellular Matrix (ECM) and Response to cytokines. Functional validation assays using patients' fibroblasts revealed defects related to cell proliferation, cell cycle, the composition of the ECM and cell migration, and showed a potential role of the inflammatory response in the pathophysiology of the disease. Furthermore, treatment with a previously described pharmacological chaperone reverted the differential expression of some of the dysregulated genes. The results presented from transcriptomic data might serve as a platform for identifying therapeutic targets for PMM2-CDG, as well as for monitoring the effectiveness of therapeutic strategies, including pharmacological candidates and mannose-1-P, drug repurposing.

Conocimiento de la puericultura y su aplicación por el médico residente en los Centros de formación en la atención del niño / Knowledge of child care and its implementation by the resident doctor at the Centers for training in childcare

La puericultura en pediatría es una rama importante d la que depende no solo la salud preventiva del niño, sino también es la base para lograr la confianza de los padres en pediatría de su niño, al escuchar y orientarles sobre aspectos que van más allá de una plática meramente terapéutica, el profesional debe suministrar educación e información, acerca de aspectos tan básicos como valiosos, como ser un adecuado desarrollo y crecimiento, una alimentación apropiada, así como también la prevención de enfermedades u accidentes.En ocasiones la consulta numerosa, no permite al pediatra disponer de tiempo para dedicar a un aspecto tan delicado, como es la enseñanza de la crianza de un niño.En los grandes hospitales de especialidad donde nos formamos aprendemos a tratar patologías y saber reconocerlas, pero es también necesario aprender a tratar al niño en su contexto sano , saber brindar a los padres un consejo veraz, científico, satisfacer sus inquietudes y sus dudas. Se decide realizar este estudio con la finalidad de saber cuál s el conocimiento del pediatra en formación, en éste campo, así como también si estos conocimientos son aplicados en la práctica de su formación.