Embryo implantation failure and early pregnancy loss remain significant challenges in assisted reproductive technology (ART). Lipid peroxidation is known to be involved in reproductive physiology. However, its role during the implantation window and its effects on post-embryo transfer outcomes remain incompletely understood. This translational study combined clinical and animal model research. Clinically, serum samples (n = 2040) and uterine fluid samples (n = 487) from patients undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles were analyzed using propensity score matching (PSM), univariate and multivariate logistic regression analysis, restricted cubic spline (RCS) analysis, and subgroup analysis. A murine model of lipid peroxidation was established by administering erastin during the implantation window to investigate its effects on endometrial receptivity and decidualization. Elevated serum levels of malondialdehyde (MDA) and non-heme iron were independently associated with recurrent implantation failure (RIF). Among patients without RIF, elevated pre-transfer serum levels of MDA, non-heme iron, 12-hydroxyeicosatetraenoic acid (12-HETE), and 15-HETE were associated with implantation failure and early pregnancy loss. Consistent with this, intrauterine MDA levels were significantly higher in patients with these pregnancy failures compared to those with ongoing pregnancy. Complementary murine studies supported these clinical observations, showing that elevated lipid peroxidation during the maternal implantation window was associated with impaired endometrial receptivity and decidualization. Elevated maternal lipid peroxidation is independently associated with RIF. In patients without RIF, it is similarly associated with implantation failure and early pregnancy loss. The endometrium appears particularly sensitive to this peroxidation, which may impair receptivity and decidualization. These support further investigation of redox-modulating strategies in ART.

BackgroundSince the Human Immunodeficiency Virus (HIV) pandemic began, roughly 80 million people have been infected, resulting in over 40 million deaths. HIV is a blood-borne disease that causes immunodeficiency by targeting CD4 T-cells. To date, there has not been a successful vaccine against HIV. In our prior studies, we have described novel epitopes on gp41 that are potential targets of future vaccine development. The 2C6 antibody (Ab) binds to a conformational epitope pocket between gp41 protomers and recognizes trimeric HIV envelope including SOSIP constructs. 2C6 has robust cross-clade Ab-dependent cell cytotoxicity (ADCC) activity and readily recognizes HIV clades A-E. Initial studies suggest that a 25-mer peptide represents enough of the structure of the 2C6 epitope to be recognized. In this study, we sought to assess if 2C6 would be a viable vaccine candidate by performing serum competition and initial murine vaccination.2C6 antibody competition with HIV + patient serum2C6 in LTNP and Elite Controllers (ECs). Comparison between groups with suppressed viral loads (Stable On therapy/EC) and those with appreciable viral loads (Low CD4s and LTNPs) show 2C6 correlates with control.Murine Vaccination shows recognition of peptide and SOSIP trimerInitial murine studies (4-6) mice were vaccinated with CoPoP formulation (lipid particle- CP), squalene adjuvants (Q), or without cobalt particle incorporation (2HP).MethodsSerum samples were obtained from HIV+ clinical groups: Elite controllers (EC), long-term non-progressors (LTNPS), stable CD4 counts on therapy, and those off therapy. Preliminary murine studies were performed using a His-tagged peptide that included the 25-amino acid peptide that formed the base of 2C6 epitope. Mice were immunized with various formulations including Cobalt-Porphyrin-Phospholipid (CoPoP or CP) formulation and a saponin based adjuvant.ResultsIn Ab/serum competition assays, Abs targeting the 2C6 epitope were enriched in LTNPs and in ECs in comparison to their control groups implying an effect of on viral control by Abs targeting the 2C6 epitope. Recognition of SOSIP trimers were particularly improved by CoPoP display of the 25-mer peptide.ConclusionThe results show that our vaccine can induce an immune response that replicates trimer binding, with Porphyrin-Phospholipids and Saponin-derived adjuvants being the best formulations. Ongoing studies are addressing a panel of antigens to assess improved recognition and assessing if this vaccine can raise Abs that have ADCC.DisclosuresJonathan Lovell, PhD, POP Biotechnologies: Ownership Interest Mark D. Hicar, MD/PhD, Pfizer: site-PI for vaccine study on Lyme

The human intestine harbors a dense community of commensal microbes that strongly shape humoral immune responses. While secretory immunoglobulin A (sIgA) has long been recognized as a key regulator of microbiota compartmentalization and intestinal homeostasis, recent studies have also highlighted important roles for secretory IgM and systemic IgG in host-microbiota interactions. In this review, we examine critical aspects of the antibody-microbiota interface, first showing the extent to which microbiota and factors influencing microbiota ecosystem such as diet shape sIgA repertoire and binding capacity. We further integrate insights from both murine and human studies to provide a comprehensive overview of how antibody-microbiota interactions are altered in autoimmune diseases and contribute both to the identification of microbial drivers of disease and to the development of new therapeutic approaches. It is noteworthy that myasthenia gravis (MG) patients have a unique microbial signature, different from other autoimmune diseases, suggesting that yet-to-be-identified gut bacteria might specifically drive the host's immune response toward MG. Finally, we discuss the mechanisms through which the microbiota may contribute to the initiation or perpetuation of dysregulated immune responses underlying autoimmunity. Given the presence of IgA autoantibodies in MG patients and the broad homology between the acetylcholine receptor and the microbial proteome, molecular mimicry and epitope spreading should be investigated as potential triggering mechanisms.

Intraperitoneal administration of cationic liposomes containing a TLR3 agonist recruits type I conventional dendritic cells and primes a local CD8+ T cell response.

We systematically reviewed published studies to assess reproducibility in miRNA expression profiles from extracellular vesicles (EVs) isolated from mouse serum. Our search specifically targeted mouse studies employing precipitation methods for EV isolation from blood and small RNA sequencing of EV-miRNAs in control groups. Out of 53 identified studies, approximately half lacked publicly available raw data, leaving four eligible studies containing sequencing data from a total of 11 mice. miRNA expression counts were standardized using z-scores for comparability. Within individual studies, miRNA profiles showed reasonable consistency; however, significant variability was observed across different studies. Principal component analysis (PCA), t-distributed stochastic neighbor embedding (t-SNE), and Spearman correlation consistently demonstrated study-specific clustering rather than biological similarity. Methodological discrepancies in EV isolation, RNA extraction protocols, and unreported confounders such as platelet contamination or blood-handling procedures likely contributed to this variability. Our findings emphasize substantial reproducibility challenges in EV-miRNA research across murine studies, highlighting an urgent need for standardized methodologies and transparent reporting to improve reliability of miRNA biomarker discovery and facilitate meta-analytic integration in preclinical research.

The standard pharmacodynamic marker in murine tuberculosis drug studies is colony-forming units ( CFU ). A faster PCR-based marker of bacterial burden is 16S rRNA. For unclear reasons, treatment reduces CFU more than 16S rRNA. We evaluated this CFU-16S gap and estimated the fraction potentially attributable to slow decay of 16S rRNA from dead Mycobacterium tuberculosis ( Mtb ) versus transition to a viable but not culturable on solid agar ( VBNC SA ) population. We quantified the CFU-16S gap during and following treatment in six BALB/c mouse studies and one in vitro study. Applying a two-population ordinary differential equation-based model of Mtb death and 16S rRNA decay, we estimated the fraction of the gap potentially attributable to dead Mtb. Using meta-regression, we estimated the association between CFU or 16S rRNA with relapse. For all regimens, CFU fell more than 16S rRNA, ranging from isoniazid-rifampin-pyrazinamide-ethambutol (CFU decreased 39-times more than 16S rRNA at week 4) to bedaquiline-pretomanid-moxifloxacin-pyrazinamide (CFU decreased >500,000-times more). The two-population model suggested that the fraction of the CFU-16S gap attributable to residual 16S rRNA from dead Mtb is modest and decreases over time. After treatment, 16S rRNA often fell while CFU rose. Four-week CFU change explained most variation in relapse (R²=0.90) while four-week 16S rRNA change did not (R²=0.24). CFU-16S gap is only partially explained by slow decay of residual 16S, suggesting development of a VBNC SA population. However, continued decrease in 16S rRNA after treatment cessation and its limited association with relapse suggests VBNC SA may be a transient rather than persistent state.

Phosphoinositides are transient signaling lipids, derived from the reversible phosphorylation of phosphatidylinositol on intracellular membranes, which serve as master regulators of many essential cellular functions. Seven distinct phosphoinositide species require precise spatiotemporal control, which is regulated by specific phosphatidylinositol kinases and phosphatases. Here, we review one such family, the inositol polyphosphate 5-phosphatases, which comprise 10 mammalian enzymes that dephosphorylate the 5-position phosphate group from the inositol head group of PtdIns(4,5)P2, PtdIns(3,5)P2, and/or PtdIns(3,4,5)P3. Despite overlapping substrate specificities, the 5-phosphatases play nonredundant roles, including in development, as demonstrated by murine and zebrafish knockout studies. Mutations in several 5-phosphatase family members are associated with multisystem developmental and congenital syndromes. Associations between 5-phosphatase gene variants and diabetes and metabolic syndrome, neurodegenerative disease, and in rare cases cancer, are also emerging. Here, we provide a comprehensive discussion of the latest advances in this field, including updates on disease modeling and mechanisms.

We describe RNA-Seq analyses conducted on nasopharyngeal swabs collected from 37 patients admitted to an Australian intensive care unit from October 2022 to August 2023. During this time, the dominant omicron sublineage infections broadly progressed from BA.5 to BA.2-like, to XBB-like, then XBC, consistent with global trends. Viral load and patient metadata correlations indicated this cohort was broadly representative of severe COVID-19 patients. Human gene expression analyses were complicated by the large range (>5 log) and variability in viral reads. Nevertheless, the comparison of XBC and BA.5 samples that had comparable viral read counts, revealed differentially expressed genes and a cellular deconvolution signature that indicated increased targeting of ciliated epithelial cells by XBC. To obtain more evidence for increased targeting of ciliated epithelial cells by the later omicron sublineage viruses, a series of mouse strains were infected with a BA.5 or a XBB isolate. Increased infection of the nasal turbinates and ciliated epithelial cells by XBB was demonstrated by viral titrations and immunohistochemistry, respectively. Compared with previous lineages, the omicron lineage showed increased targeting of ciliated epithelia in the upper respiratory tract, with the data presented herein suggesting this trend continued for the omicron sublineages.

Patients suffering carbon monoxide (CO) poisoning exhibit elevations of ∼1-μm diameter blood-borne microparticles that murine studies have demonstrated to be responsible for a weeks-long cycle of neuroinflammation leading to functional neurological deficits. We hypothesized that an early event in the cycle is enhanced glymphatic flow to release brain-derived MPs, and that the adherence of circulating MPs to the central nervous system vasculature occurs via endothelial CD36 to cause neutrophil sequestration, which disrupts the blood-brain barrier. Results demonstrate that endothelial CD36 engagement of microparticles is required for pathological events, including neutrophil sequestration, leading to a 2.5 ± 0.6-fold increased vasculature leakage of 6 MDa dextran and induction of neuroinflammatory proteins. These changes increase glymphatic flow by 95 ± 26% based on magnetic resonance imaging and fluorescent tracer uptake, resulting in the release of brain-derived microparticles capable of activating neutrophils that complete a cycle of progressive neuroinflammation. The cyclic cascade of events, shown to persist for 3 wk, failed to occur in CD36 knock-out mice and those conditionally deficient in endothelial CD36 (CD36flox/flox; Tie2-Cre+). We conclude that endothelial CD36 engagement of circulating microparticles precedes and is required for neutrophil adherence to perpetuate the neuroinflammatory cycle involving brain-derived and blood-borne microparticles.NEW & NOTEWORTHY CO-induced neuroinflammation requires endothelial CD36 engagement of circulating microparticles that trigger neutrophil vascular adherence, neuroinflammation, and a transient elevation of glymphatic flow, establishing a self-perpetuating neuroinflammatory cycle.

Periodontal disease, a bacterial infection affecting a large percentage of the world's population, is an important risk factor for several systemic diseases and is significantly worsened by diabetes. To investigate how diabetes exacerbates the inflammatory response to bacteria in this disease, we combined insights from murine and human studies. Through single-cell RNA sequencing, we identified a compelling hyperglycemia-driven molecular pathway: the upregulation of CD137L in dendritic cells and increased expression of its receptor, CD137, in γδ T-cells. The CD137L-CD137 axis emerged as a pivotal mediator of diabetes-induced inflammatory tissue destruction. Antibody-mediated inhibition of CD137L markedly reduced the diabetes-driven bone loss, neutrophil recruitment, expansion of γδ T-cells, and excessive infiltration by IL17A+ cells. In vitro studies further validated these findings and established that high glucose-mediated dysregulation of dendritic cells dramatically altered γδ T-cell activity in co-culture systems via CD137L. The essential role of dendritic cells as CD137L producers in vivo was definitively established through lineage-specific Akt1 deletion, which abrogated CD137L expression in these cells and reversed the adverse effects of hyperglycemia on leukocyte responses to bacterial pathogens in vivo. Conversely, activation of CD137 with an agonist in normal animals recapitulated diabetes-induced abnormalities in the inflammatory response and accelerated bone loss. These findings elucidate a key mechanism underlying diabetes-induced immune dysregulation and inflammatory damage, and point to the CD137L-CD137 pathway as a promising therapeutic target, offering potential insights into mitigating other diabetes-associated complications linked to inflammatory changes.

Osteogenesis imperfecta (OI) is a heterogenous type 1 collagenopathy characterized by recurrent fractures, decreased bone mass, and shorter stature. Bisphosphonates reduce fracture incidence in children with OI but do not improve growth velocity. C-type natriuretic peptide (CNP) is produced in the growth plate (also in the brain and heart) and positively regulates linear bone growth; people with OI have been shown to have a reduced serum level of CNP. This pilot study evaluated whether a CNP analog combined with alendronate (ALN) improves growth and bone mineral density in oim/oim (OIM) mice, a model of moderate-to-severe Type III OI. Two-week-old OIM and WT mice received weekly ALN and one of three CNP regimens: 10 μg/kg three days/week (low), 20 μg/kg three days/week (medium), or 20 μg/kg five days/week (high). Controls received saline. Faxitron images were taken at two, eight, and 14 weeks (sacrifice) to assess fracture incidence and measure femoral length and vertebral height. Microcomputed tomography (micro-CT) was used to assess bone microstructural parameters of the femur ex vivo. The high-dose group had no fractures post-sacrifice; one fracture each was observed in the low and medium dose groups. Femoral length increased in all treated groups, with the high dose group showing the greatest increase (8.2%, significant) in OIM mice. Vertebral height increased in all treated groups; low and high dose groups had greater, comparable increases than the medium group in OIM mice. All treated groups showed increased trabecular bone mineral density (BMD). Cortical tissue mineral density (TMD), BMD, and thickness were also elevated in all treated groups compared to controls. In conclusion, CNP analog adjuvant treatment enhanced linear growth and bone quality without compromising fracture reduction, providing benefits not seen with bisphosphonates alone. These results will inform optimal dosing for future studies. A full murine study is planned to further evaluate therapeutic potential for translation to humans.

This paper outlines a systematic research agenda to evaluate gamete quality and safety after IVG, focusing on key control points and biological barriers that may limit the safety of clinical IVG. The relevance of the study is determined by the current trend of rapid development of IVG as a direction of regenerative and reproductive medicine that can help to overcome infertility, loss of fertility and other reproductive dysfunctions. The purpose of the study is to systematize the existing methods for quality control of IVG gametes, assess their applicability and limitations at each stage of the technological cycle, and identify biological barriers to the production of safe gametes in vitro. The scientific novelty of the study is a four-stage model of quality control (CCT-1‑CCT-4) taking into account the genetic, epigenetic and functional aspects. Unlike other reviews on this topic, emphasis is placed on the fact that epigenetic instability, global genomic demethylation failure, imprinting errors, and a history of memory accumulation from reprogrammed iPSCs are not only technological issues but also biological limits to the clinical application of human IVG. The main conclusion of the present review is that the recently developed genetic quality control techniques, including PGT-An and whole-genome sequencing, have been reported to identify aneuploidies and mutations reliably. Current epigenetic diagnostic methods are destructive and not yet suitable for routine clinical selection of gametes. However, evidence from murine studies indicates that the functional capacity of IVG gametes is diminished by more than 10‑fold compared to those derived in vivo, suggesting that epigenetic changes associated with IVG will likely affect the organism as a whole. This article should therefore be of broad interest to researchers in reproductive biology, cellular engineering, and biomedical regulation, and to those assessing new reproductive technologies.

Gut-initiated mucosal and systemic immunity against SARS-CoV-2 via an oral hyaluronic acid/chitosan vaccine coacervate.

One of the hallmarks of Osteogenesis Imperfecta (OI) is phenotypic variability among individuals with the same mutation. The aim of our study is to investigate the under-explored role of osteoblast differentiation in OI phenotypic variability by using human and murine OI osteoblasts. This is the first comparative study of osteoblasts from OI patients vs. healthy pediatric controls. We investigated osteoblasts carrying COL1A1 substitutions Gly352Ser and Gly589Ser, each expressed in two unrelated patients differing in phenotypic severity. Osteoblasts from type III OI patients with both mutations deposited significantly less mineral vs. type IV. RNA-Seq showed osteoblasts from type IV OI patients with different mutations had downregulated mitochondrial pathways, while osteoblasts from type III OI patients showed downregulation of extracellular matrix pathways. Puromycin assay demonstrated osteoblast protein synthesis was significantly upregulated in type III vs. type IV OI patients. UPR PERK and BiP were reduced in osteoblasts with Gly352Ser from type III and IV OI patients and in osteoblasts with Gly589Ser from a type III OI patient, while both proteins were increased in Gly589Ser osteoblasts from the type IV patient. Additionally, in a murine comparative study, Col1a1 Gly349Ser, called Brtl Ser, showed a much more severe skeletal phenotype than Brtl Cys. Brtl Ser calvarial osteoblasts had reduced collagen secretion and folding with abnormal dermal collagen fibrils vs. wildtype. Also, Brtl Ser osteoblasts showed condensed actin filaments but a similar mineral deposition as Brtl Cys. Electron microscopy revealed elongated mitochondria with cristae dropout in patient and mutant murine osteoblasts. Our study yielded novel insights highlighting osteoblast differentiation, mineralization, and a potential role of mitochondria in OI pathology and phenotypic variability.

GY971 mitigates inflammation by reducing neutrophil recruitment in cystic fibrosis Ex Vivo and In Vivo models.

385 Basophil infiltration in sentinel lymph nodes of early-stage melanoma: potential pro-metastatic role suggested by human and murine studies

Design of a peripherally biased NPSR1 antagonist for neuropeptide S induced inflammation.

Low-Dose Cardiac Radiation Improves Electrical Function and Reduces Ventricular Arrhythmogenesis in Mice With Nonischemic Cardiomyopathy.

We are living in an era where food allergy is increasingly prevalent, and shrimp allergy (SA) is among the most common and potentially severe reactions worldwide. Significant efforts have been made to improve diagnostic accuracy and treatment options. However, diagnosing SA remains challenging due to its diverse clinical presentations and the complexity of shrimp allergens. The pathogenesis of SA is complicated by various allergens sensitization, epithelial barrier disruption and gut microbiota dysbiosis. To date, at least ten shrimp allergens have been identified, but sensitization profiles vary significantly across populations. Promising novel immunotherapy approaches have been explored, showing potential in murine models. The use of physiologically relevant experimental systems, from in vivo models (e.g., murine studies) to advanced ex vivo human-based techniques (including organoids, organ-on-a-chip platforms, and tissue slice cultures), offers promising alternative for studying biological processes that are difficult to investigate directly in humans. These models have emerged as a valuable tool in food allergy research by providing critical insights into food-gut interactions, gut microbiota-host dynamics epithelial barrier integrity and cross-talk between epithelia and immune cells, and signaling and inflammatory markers. This review aims to summarize recent advancements in the diagnosis and treatment of SA, and the potential in vivo/ex-vivo models in SA research.

Objective.While FLASH radiotherapy is known to reduce skin damagein vivofrom ultra-high dose rate (UHDR) irradiation relative to conventional dose rates (CDR), it is not clear whether this sparing is preserved when delivered as fractionated. This study was designed to directly assess whether three daily fractions would maintain the sparing effects in murine leg models and preserve the murine skin sparing with single fraction treatments.Approach.C57Bl/6j female mice were irradiated with 9 MeV UHDR and CDR beams from a FLASH-capable Mobetron system, in a dose escalation study with doses ranging from single dose 22-30 Gy in a single fraction to three daily fractions of 10-16 Gy. The biological responses were scored by a visual skin damage response rubric using up to 5 blinded observers, and a leg contracture assay as a secondary measure of damage.Main results.There was a monotonic dose response in all treatment groups with irradiation dose, with skin damage onset at 9-10 d. In the single dose group a significant FLASH sparing was seen with a FLASH modifying factor (FMF) of approximately 0.73. Similarly in the single dose groups there were significant leg contracture differences between UHDR and CDR groups after 12-15 d. In comparison, there was no significant skin damage sparing between UHDR and CDR in the three daily fraction dose groups, and reduced sparing in the leg contracture assay.Significance.The results of this murine study show a significant reduction of the FLASH effect when the dose is split into three fractions of 10-16 Gy each, whereas there were substantial FLASH sparing effects noted for the single fractions of 22-30 Gy, showing a FMF of ∼0.73. These observations provide the data needed to optimize FLASH sparing experiments in further translational studies.