Comprehensive genomic filtering algorithm to expose the cause of skewed X chromosome inactivation. The proof of concept in female haemophilia expression.

BACKGROUND: Exploring the expression of X linked disorders like haemophilia A (HA) in females involves understanding the balance achieved through X chromosome inactivation (XCI). Skewed XCI (SXCI) may be involved in symptomatic HA carriers. We aimed to develop an approach for dissecting the specific cause of SXCI and verify its value in HA. METHODS: A family involving three females (two symptomatic with severe/moderate HA: I.2, the mother, and II.1, the daughter; one asymptomatic: II.2) and two related affected males (I.1, the father and I.3, the maternal uncle) was studied. The genetic analysis included F8 mutational screening, multiplex ligation-dependent probe amplification, SNP microarray, whole exome sequencing (WES) and Sanger sequencing. XCI patterns were assessed in ectoderm/endoderm and mesoderm-derived tissues using AR-based and RP2-based systems. RESULTS: The comprehensive family analysis identifies I.2 female patient as a heterozygous carrier of F8:p.(Ser1414Ter) excluding copy number variations. A consistent XCI pattern of 99.5% across various tissues was observed. A comprehensive filtering algorithm for WES data was designed, developed and applied to I.2. A Gly58Arg missense variant in VMA21 was revealed as the cause for SXCI.Each step of the variant filtering system takes advantage of publicly available genomic databases, non-SXCI controls and case-specific molecular data, and aligns with established concepts in the theoretical background of SXCI. CONCLUSION: This study acts as a proof of concept for our genomic filtering algorithm's clinical utility in analysing X linked disorders. Our findings clarify the molecular aspects of SXCI and improve genetic diagnostics and counselling for families with X linked diseases like HA.

The synthetic phospholipid C8-C1P determines pro-angiogenic and pro-reparative features in human macrophages restraining the proinflammatory M1-like phenotype.

Monocytes (Mo) are highly plastic myeloid cells that differentiate into macrophages after extravasation, playing a pivotal role in the resolution of inflammation and regeneration of injured tissues. Wound-infiltrated monocytes/macrophages are more pro-inflammatory at early time points, while showing anti-inflammatory/pro-reparative phenotypes at later phases, with highly dynamic switching depending on the wound environment. Chronic wounds are often arrested in the inflammatory phase with hampered inflammatory/repair phenotype transition. Promoting the tissue repair program switching represents a promising strategy to revert chronic inflammatory wounds, one of the major public health loads. We found that the synthetic lipid C8-C1P primes human CD14+ monocytes, restraining the inflammatory activation markers (HLA-DR, CD44, and CD80) and IL-6 when challenged with LPS, and preventing apoptosis by inducing BCL-2. We also observed increased pseudo-tubule formation of human endothelial-colony-forming cells (ECFCs) when stimulated with the C1P-macrophages secretome. Moreover, C8-C1P-primed monocytes skew differentiation toward pro-resolutive-like macrophages, even in the presence of inflammatory PAMPs and DAMPs by increasing anti-inflammatory and pro-angiogenic gene expression patterns. All these results indicate that C8-C1P could restrain M1 skewing and promote the program of tissue repair and pro-angiogenic macrophage.

Estudio exploratorio de eficacia de ivermectina combinada a α- PD-1 en cáncer colorrectal resistente a quimioinmunoterapia / EXPLORATORY EFFECTIVENESS STUDY OF IVERMECTIN COMBINED WITH α-PD-1 IN CHEMOTHERAPY RESISTANT COLORRECTAL CANCER

[RESUMEN]. Las terapias inmunológicas con inhibidores de checkpoints (ICIs) han revolucionado el abordaje del cáncer colorrectal (CCR), pero su efectividad se restringe a tumores inmunorreactivos con deficiencia en la reparación de errores tipo mismatch (dMMR). La ivermectina (IVM), un agente antiparasitario, se propone como posible estrategia terapéutica debido a su impacto en la muerte celular inmunogénica (MCI) y la reversión de resistencia a medicamentos. La investigación evaluó el efecto antineoplásico de IVM combinado con α-PD-1 empleando el modelo murino CT-26, una línea de CCR KRAS-mutada y competentes para MMR. El análisis bioinformático mediante la plataforma GEPIA2 empleandola base TCGA confirmó la expresión diferencial de blancos moleculares de IVM en tejido tumoral versus normal, siendo más alta en tumores con inestabilidad microsatelital baja (MSI-L)/microsatelital estable (MSS) que en inestabilidad microsatelital alta (MSI-H). En experimentos in vitro, CT-26 mostró alta sensibilidad a IVM (IC50: 11 µM, luego de exposición por 72 horas), alterando el metabolismo y aumentando la secreción de IL-6. El análisis proteómico identificó 17 proteínas sobreexpresadas y 8 inhibidas, relacionadas con evasión inmunológica y proliferación celular. En ratones BALB/c portadores de tumores CT-26, la terapia combinada de IVM y α-PD-1 redujo significativamente el crecimiento tumoral y la progresión metastásica. La preinmunización con células CT-26 tratadas con IVM disminuyó la incidencia y la progresión tumoral. IVM podría potenciar la respuesta a ICIs en tumores "fríos". Estos hallazgos sugieren que la combinación de IVM y α-PD-1 puede mejorar la inmunorreactividad y respuesta terapéutica en CCR.

[ABSTRACT]. Matrix Assisted Laser DesorptionIonization ­ Time of Flight ­ MassSpectrometry (MALDI-TOF-MS) has emerged as anoutstandingtechnique in thefieldofclinicalmicrobiology, with a simple methodology and deliveryof precise results in anexceptionally short timeframe. Thistechnology has garnered notable success in recentyears, establishing as a fundamental toolboth in thecharacterizationofmicroorganisms and translationalresearch.Thecombinationoftheinherentfeaturesofthistechniquewiththepotentialof machine learninganalysis has provento be ofgreatvalue in clinicalmicrobiology, particularly in theantibioticresistancefield. Itsapplication has acceleratedbacterial diagnosis and opened new perspectives in criticalareasof medicine, such sepsis and oncology. In Argentina, several research groups actively contributing to its expansión, applying MALDI-TOF-MS in the fight against infectious diseases, including the COVID-19 pandemic. Theseeffortspromiseto continue drivingresearch and clinical diagnosis in the country and worldwide.

Growth conditions affect biofilms of Staphylococcus aureus producing mastitis: Contribution of MALDI-TOF-MS to strain characterization.

Bovine mastitis is a disease of dairy cattle prevalent throughout the world that causes alterations in the quality and composition of milk, compromising technological performance. Staphylococcus aureus is one of the most important pathogens that produce clinical, subclinical, and chronic mastitis. Biofilms are considered a virulence factor necessary for the survival of S. aureus in the mammary gland. Its zoonotic potential is important not only for the dairy industry sector but also for public health. This study aimed to evaluate the effect of different growing culture conditions on the biofilm formation of S. aureus isolated from mastitis and to test the MALDI-TOF-MS's ability to discriminate among different biofilm formation levels. Fluids commonly found in the dairy environment were incorporated to approach the pathogen's behavior in natural surroundings. PIA production was also evaluated. All strains were able to form high biofilms in TSB, TSBg, and milk. Milk changed the behavior of some strains which formed more biofilms in this medium than in TSBg. The free iron medium CTSBg and milk whey inhibited the biofilm formation of the most strains. MALDI-TOF-MS performance was an excellent tool to discriminate between high, moderate, and low biofilm producers strains of S. aureus in each media, confirming the results of crystal violet assay. PIA production was variable among the strains and showed a media-dependent behavior. Our data highlights the importance of considering the growing conditions that mimic the natural ones to the study of biofilm formation in vitro.