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Kaur, N.

Publications and source records attributed to Kaur, N..

At least 19 recordsLinked to original sources

ATG16L2 creates a VAIL-dedicated heterodimer with ATG16L1

The ATG8 conjugation machinery supports both canonical autophagy, in which ATG8 proteins are lipidated on forming autophagosomes, and CASM, in which ATG8 proteins are conjugated to stressed single-membrane compartments. How cells allocate this shared machinery between these competing membrane programs remains unclear. Here, we identify ATG16L2 as a specialized regulator of V-ATPase-responsive ATG8 lipidation (atg8ylation). ATG16L2 does not form stable homodimers and is inactive in the absence of ATG16L1, but it becomes functional through heterodimerization with ATG16L1. The ATG16L1-ATG16L2 heterodimer constitutes a VAIL-competent E3-like complex that is excluded from WIPI2-positive autophagic membranes but readily recruited to stressed lysosomes. ATG16L2 also confers VAIL activity onto the otherwise VAIL-deficient ATG16L1 isoform. We propose that ATG16L1 homodimers and ATG16L1-ATG16L2 heterodimers represent alternative assemblies of the ATG8 conjugation machinery: ATG16L1 homodimers are dedicated to WIPI2-positive autophagic membranes, whereas ATG16L1-ATG16L2 heterodimers containing either ATG16L1 isoform form a VAIL-selective assembly.

molecular biology↗

Species- and Topic-aware Representation Learning for Antimicrobial Peptide Discovery

Antimicrobial resistance poses a major global health challenge, necessitating efficient strategies to discover potent antimicrobial peptides (AMPs). While recent generative models can produce many candidate sequences, experimentally validating all generated peptides in wet labs is impractical due to the high costs and time involved in such measurements. As a result, there is a strong demand for accurate predictions of peptide efficacy, typically measured as the minimum inhibitory concentration (MIC). We introduce STAMP, a framework for Species- and Topic-aware Representation Learning in AMP Discovery. This unified machine learning framework allows for cross-species predictions of AMP activity. STAMP integrates protein language model embeddings with species conditioning and topic-aware representations that capture sequence-level patterns, enabling generalizable predictions across multiple bacterial species within a single model. We evaluated STAMP on three benchmark datasets, which include two previously published datasets and a newly curated dataset derived from DBAASP, addressing duplicates and inconsistencies systematically. STAMP achieved strong predictive performance across these datasets, demonstrating a Pearson correlation coefficient (PCC) of 0.837 and an R2 of 0.70, outperforming several baseline models. Importantly, we further validated our prediction model using peptides that were experimentally tested for their antimicrobial activity against E.coli. and S.epidermidis bacteria, demonstrating its real-world applicability. Furthermore, residue-level importance analyses provide insights into the sequence determinants governing antimicrobial activity. Together, these results establish STAMP as a scalable framework for MIC prediction and an effective computational tool for accelerating AMP discovery and optimization.

bioinformatics↗

Leveraging whole-genome re-sequencing for diversity, population structure, and a public mid-density genotyping enrichment panel in crimson clover (Trifolium incarnatum L.) for breeding purposes

AO_SCPLOWBSTRACTC_SCPLOWCrimson clover (Trifolium incarnatum L.) is an obligately outcrossing, cool-season annual legume valued for forage and cover cropping, yet genomic resources to support systematic improvement are limited. We performed the first and most comprehensive whole-genome resequencing (WGR) of global crimson clover germplasm to (i) characterize diversity and population structure and (ii) develop a public mid-density enrichment capture panel for breeding applications. A core set of 45 accessions sequenced at [~]50X generated 5.84 million variants, while 149 additional accessions sequenced at [~]2.54X yielded 17.05 million variants. After stringent filtering, we retained 542,790 high-confidence SNPs from the high-coverage dataset and [~]2.4 million from the low-pass cohort. Population analyses (PCA, ADMIXTURE) revealed compact clustering of cultivars, broader dispersion of wild and uncertain-status accessions, and low overall differentiation (FST = 0.0105) with excess heterozygosity (FIS = -0.0592), consistent with obligate outcrossing. Guided by these resources, we designed a 28,913-SNP TWIST hybrid-capture panel enriched for genic regions and evenly distributed across seven chromosomes. This panel is being deployed within Auburn Universitys crimson clover breeding program to support population improvement and cultivar development. The resulting genomic resources provide a reproducible, mid-density genotyping platform for trait discovery, predictive breeding, and diversity monitoring. Together, these advances bring crimson clover genomic resources on par with other legumes such as soybean (Glycine max (L.) Merr.) and alfalfa (Medicago sativa), establishing a robust foundation for genomics-assisted improvement of this key cover and forage crop in U.S. sustainable agriculture. CORE IDEASO_LIWhole-genome re-sequencing of 194 crimson clover accessions revealed >21 M variants. C_LIO_LIHigh-confidence SNP catalogs from 50X and 2X data enable cost-effective genotyping. C_LIO_LIGenetic diversity is weakly structured, with cultivars clustering narrowly by origin. C_LIO_LIA 28,913 SNP enrichment panel delivers uniform genome coverage and >75% genic content. C_LIO_LIThese genomic tools accelerate GWAS, genomic selection, and breeding innovation. C_LI

genomics↗

Adaptive Evolution of Gene Regulatory Networks in Mammalian Neocortical Neurons

Mammals have evolved a plethora of adaptations that have enabled them to thrive in diverse environments. Among the most significant is the emergence of a more complex brain, exemplified by the dramatic transformation of the dorsal cortex from a single layer of excitatory projection neurons (ExNs) in ancestors to a multilayered cerebral neocortex enriched with diverse intratelencephalic (IT) and extratelencephalic (ET) ExN subtypes. These ExNs established specialized projection systems, such as the corticospinal tract and corpus callosum, enhancing brain connectivity and functionality. However, the evolutionary mechanisms underlying these mammalian-specific adaptations remain elusive. By comparing the landscape of gene expression and cis-regulatory elements (CREs) in mouse ExN subtypes and by cross-species examination of mammalian and non-mammalian CREs, we identified mammalian-specific CREs and expression patterns. The mammalian-specific CREs include a subset bound by ZBTB18 that are associated with genes defining IT and ET subtypes and connectivity. Both ZBTB18 and these target genes have previously been implicated in intellectual disability and autism. Deletion of Zbtb18 in mouse ExNs dysregulated target gene expression, reduced molecular diversity, diminished corticospinal and callosal projections, and increased intrahemispheric cortico-cortical association projections to the prefrontal cortex, resembling features of non-mammalian dorsal pallium. Interestingly, ZBTB18 binding motifs are highly enriched in callosally projecting IT-biased CREs, where they show higher conservation specifically in mammals. This study uncovers critical components and mammalian-specific evolutionary adaptations within a regulatory node essential for neocortical ExN identity and connectivity, with implications for neurodevelopmental and neuropsychiatric disorders.

neuroscience↗

Engineering IspH for Enhanced Terpenoid Yield: Computational and Molecular Dynamics Studies

Terpenoids play a vital role in pharmaceuticals, biofuels, and various industries, and they are produced through the methylerythritol phosphate (MEP) pathway, with IspH catalyzing the final step. This study explores IspH homologs in Bacillus and other bacteria to aid in enzyme engineering. Sequence analysis showed a conservation range of 46-79%. Phylogenetic analysis (log-likelihood -71,581.08, bootstrap 80-100) validated the evolutionary relationships. Structural modeling revealed conserved functional motifs. Molecular docking indicated HMBPP binding affinities between -4.9 and -6.4 kcal/mol, while molecular dynamics simulations confirmed the stability of the complex (RMSD 2.02-3.45 [A], Rg 21.56-22.06 [A], with a decrease in SASA upon binding). Significant hydrogen bonds were noted with His131, Asn227, and Ser271. This thorough analysis of IspH conservation, structure, and stability, along with co-evolving residue networks, underscores the potential of Bacillus IspH variants for improved terpenoid production and lays the groundwork for targeted enzyme engineering.

bioengineering↗

Anionic lipid catalyzes the generation of cytotoxic insulin oligomers

Misfolding and aggregation of proteins into amyloidogenic assemblies are key features of several metabolic and neurodegenerative diseases. Human insulin has long been known to form amyloid fibrils under various conditions, which affects its bioavailability and function. Clinically, insulin aggregation at recurrent injection sites poses a challenge for diabetic patients who rely on insulin therapy. Furthermore, decreased responsiveness to insulin in type 2 diabetic (T2D) patients may lead to its overproduction and accumulation as aggregates. Earlier reports have reported that various factors such as pH, temperature, agitation, and the presence of lipids or other proteins influence insulin aggregation. Our present study aims to elucidate the effects of non-micellar anionic DMPG (1,2-dimyristoyl-sn-glycero-3-phosphoglycerol) lipids on insulin aggregation. Distinct pathways of insulin aggregation and intermediate formation were observed in the presence of DMPG using a ThT fluorescence assay. The formation of soluble intermediates, alongside large insulin fibrils, was observed in insulin incubated with DMPG via TEM, DLS and NMR, as opposed to insulin aggregates generated without lipids. 13C magic angle spinning solid-state NMR and FTIR experiments indicated that lipids do not alter the conformation of insulin fibrils but do alter the time scale of motion of aromatic and aliphatic sidechains. Furthermore, the soluble intermediates were found to be more cytotoxic as compared to fibrils generated with or without lipids. Overall, our study elucidates the importance of anionic lipids in dictating the pathways and intermediates associated with insulin aggregation. These findings could be useful in determining various approaches to avoid toxicity and enhance the effectiveness of insulin in therapeutic applications.

biophysics↗

Molecular Specification of Claustro-Amygdalar and Paleocortical Neurons and Connectivity

The ventropallial excitatory neurons (ExNs) in the claustro-amygdalar complex and piriform cortex (PIR; part of paleocortex) form crucial reciprocal connections with the prefrontal cortex (PFC), integrating cognitive and sensory information that result in adaptive behaviors. Early-life disruptions in these circuits are linked to neuropsychiatric disorders, highlighting the importance of understanding their development. Our study uncovers that transcription factors SOX4, SOX11, and TFAP2D play a pivotal role in the development, identity, and PFC connectivity of these neurons. Using mouse models, we demonstrate that the absence of transcription factors SOX4 and SOX11 in post-mitotic ExNs dramatically reduces the size of the basolateral amygdala complex (BLC), claustrum, and PIR. SOX4 and SOX11 control BLC formation through direct regulation of Tfap2d expression. Cross-species analyses, including humans, identified conserved Tfap2d expression in developing ExNs of BLC, claustrum, paleocortex including PIR, and the associated transitional areas of the frontal, insular and temporal cortex. While the loss and haploinsufficiency of Tfap2d yield similar alterations in learned threat behaviors, differences emerge in the manifestation of Tfap2d dosage, particularly in terms of changes observed in BLC size and the connectivity pattern between the BLC and PFC. This underscores the significance of Tfap2d dosage in orchestrating developmental shifts in BLC-PFC connectivity and behavioral modifications reminiscent of symptoms of neuropsychiatric disorders. Together, these findings reveal key elements of a conserved gene regulatory network that shapes the development and function of crucial ventropallial ExNs and their PFC connectivity and offer insights into their evolution and alterations in neuropsychiatric disorders.

neuroscience↗

Prognostic Significance of Potential Target Networks and P16INK4a In Early Diagnosis of Non-Small Cell Lung Cancer

This study aimed to identify the prognostic signature of p16INK4a and related genes in non-small cell lung cancer (NSCLC). Since non-small cell lung cancer shows a poor prognosis, the 5-year survival rate in advanced stages is low. This emphasizes the need to identify more reliable diagnostic biomarkers for the early diagnosis of NSCLC and understand the molecular mechanisms underlying the progression of the disease. The role of P16 in essential cellular pathways are still unknown. Understanding its function and the mechanisms underlying its dysregulation could potentially lead to the development of targeted therapies for certain cancers. To address this, bioinformatics analyses revealed differential expression of genes in lung tumour tissues vs control samples. The interactions among the identified DEGs can help better understand the underlying molecular mechanism of NSCLC. We investigated the correlation between p16INK4a expression and genes involved in the relevant interactive pathways in early-stage NSCLC. These can serve as potential diagnostic and therapeutic biomarkers for NSCLC.

bioinformatics↗

Circulating miR-126-3p is a mechanistic biomarker for knee osteoarthritis

As a chronic joint disease, osteoarthritis (OA) is a major contributor to pain and disability worldwide, and yet there are currently no validated soluble biomarkers or disease-modifying treatments. Since microRNAs are promising mechanistic biomarkers that can be therapeutically targeted, we aimed to prioritize reproducible circulating microRNAs in knee OA. We performed secondary analysis on two microRNA-sequencing datasets and found circulating miR-126-3p to be elevated in radiographic knee OA compared to non-OA individuals. This finding was validated in an independent cohort (N=145), where miR-126-3p showed an area under the receiver operating characteristic curve of 0.91 for distinguishing knee OA. Measuring miR-126-3p in six primary human knee OA tissues, subchondral bone, fat pad and synovium exhibited the highest levels, and cartilage the lowest. Following systemic miR-126-3p mimic treatment in a surgical mouse model of knee OA, we found reduced disease severity. Following miR-126-3p mimic treatment in human knee OA tissue explants, we found direct inhibition of genes associated with angiogenesis and indirect inhibition of genes associated with osteogenesis, adipogenesis, and synovitis. These findings suggest miR-126-3p becomes elevated during knee OA and mitigates disease processes to attenuate severity.

molecular biology↗

Comparative genomics of the extremophile Cryomyces antarcticus and other psychrophilic Dothideomycetes

Cryomyces antarcticus is an endolithic fungus that inhabits rock outcrops in Antarctica. It survives extremes of cold, humidity and solar radiation in one of the least habitable environments on Earth. This fungus is unusual because it produces heavily melanized, meristematic growth and is thought to be haploid and asexual. Due to its growth in the most extreme environment, it has been suggested as an organism that could survive on Mars. However, the mechanisms it uses to achieve its extremophilic nature are not known. Over a billion years of fungal evolution has enabled representatives of this kingdom to populate almost all parts of planet Earth and to adapt to some of its most uninhabitable environments including extremes of temperature, salinity, pH, water, light, or other sources of radiation. Comparative genomics can provide clues to the processes underlying biological diversity, evolution, and adaptation. This effort has been greatly facilitated by the 1000 Fungal Genomes project and the JGI MycoCosm portal where sequenced genomes have been assembled into phylogenetic and ecological groups representing different projects, lifestyles, ecologies, and evolutionary histories. Comparative genomics within and between these groups provides insights into fungal adaptations, for example to extreme environmental conditions. Here, we analyze two Cryomyces genomes in the context of additional psychrophilic fungi, as well as non-psychrophilic fungi with diverse lifestyles selected from the MycoCosm database. This analysis identifies families of genes that are expanded and contracted in Cryomyces and other psychrophiles and may explain their extremophilic lifestyle. Higher GC contents of genes and of bases in the third positions of codons may help to stabilize DNA under extreme conditions. Numerous smaller contigs in C. antarcticus suggest the presence of an alternative haplotype that could indicate that the sequenced isolate is diploid or dikaryotic. These analyses provide a first step to unraveling the secrets of the extreme lifestyle of C. antarcticus.

genomics↗

Identification and functional characterisation of a locus for target site integration in Fusarium graminearum

BackgroundFusarium Head Blight is a destructive floral disease of different cereal crops. The Ascomycete fungus Fusarium graminearum (Fg) is one of the main causal agents of FHB in wheat and barley. The role(s) in virulence of Fg genes include genetic studies that involve the transformation of the fungus with different expression cassettes. We have observed in several studies where Fg genes functions were characterised that integration of expression cassettes occurred randomly. Random insertion of a cassette may disrupt gene expression and/or protein functions and hence the overall conclusion of the study. Target site integration (TSI) is an approach that consists in identifying a chromosomal region where the cassette can be inserted. The identification of a suitable locus for TSI in Fg would avert the potential risks of ectopic integration. ResultsHere, we identified a highly conserved intergenic region on chromosome 1 suitable for TSI. We named this intergenic region the TSI locus 1. We developed an efficient cloning vector system based on the Golden Gate method to clone different expression cassettes for use in combination with TSI locus 1. We present evidence that integrations in the TSI locus 1 affects neither fungal virulence nor fungal growth under different stress conditions. Integrations at the TSI locus 1 resulted in the expression of different gene fusions. In addition, the activities of Fg native promoters were not altered by integration into the TSI locus 1. We have developed a bespoke bioinformatic pipeline to analyse the existence of ectopic integrations and tandem insertions of the cassette that may occurred during the transformation process. Finally, we established a protocol to study protein secretion in wheat coleoptiles using confocal microscopy and the TSI locus 1. ConclusionThe TSI locus 1 can be used in Fg and potentially other cereal infecting Fusarium species for diverse studies including promoter activity analysis, secretion, protein localisation studies and gene complementation. The bespoke bioinformatic pipeline developed in this work can be an alternative to southern blotting, the gold standard technique to identify ectopic integration and tandem insertions in fungal transformation.

genetics↗

Endogenous oscillatory rhythms and interactive contingencies jointly influence infant attention during early infant-caregiver interaction

Almost all early cognitive development takes place in social contexts. At the moment, however, we know little about the neural and micro-interactive mechanisms that support infants attention during social interactions. Recording EEG during naturalistic caregiver-infant interactions (N=66), we compare two different accounts. Traditional, didactic perspectives emphasise the role of the caregiver in structuring the interaction, whilst active learning models focus on motivational factors, endogenous to the infant, that guide their attention. Our results show that, already by 12-months, intrinsic cognitive processes control infants attention: fluctuations in endogenous oscillatory neural activity associated with changes in infant attentiveness. In comparison, infant attention was not forwards-predicted by caregiver gaze or vocal behaviours. Instead, caregivers rapidly modulated their behaviours in response to changes in infant attention and cognitive engagement, and greater reactive changes associated with longer infant attention. Our findings suggest that shared attention develops through interactive but asymmetric, infant-led processes that operate across the caregiver-child dyad.

neuroscience↗

An efficient hairy root system for genome editing of a β-ODAP pathway gene in Lathyrus sativus

Grass pea (Lathyrus sativus) is an ideal legume crop for resource-poor farmers, having resistance to various biotic and abiotic stresses. The seeds of this plant are rich in protein and are the only known dietary source of L-homoarginine. Moreover, it thrives with minimal inputs making it a promising crop in grain legume breeding programs with immense potential for food security. Despite these advantages, the global area under its cultivation has decreased because of the presence of an antinutrient compound, {beta}-N-oxalyl-L-,{beta}-diamino propionic acid ({beta}-ODAP), which results in neurolathyrism both in humans and animals. Multiple efforts in the past have resulted in the development of improved varieties with low ODAP. Still, due to variations in response to the environment, stable low-ODAP lines have not been developed for large-scale cultivation. In this paper, we report in planta characterization of Oxalyl-CoA Synthetase (OCS) involved in the oxalylating step leading to {beta}-ODAP production. We established a hairy root transformation system for Lathyrus and demonstrated the genome editing of LsOCS. Further, we show that oxalate accumulates in these hairy roots due to loss-of-function of the OCS gene. This is the first report of functional analysis of a Lathyrus gene in Lathyrus. The hairy root genome editing system we developed can be used as a quick system for functional studies of Lathyrus genes.

plant biology↗

SifA SUMOylation governs Salmonella intracellular survival via modulation of lysosomal function

Gastroenteritis causing pathogen Salmonella Typhimurium (S. Tm) during its infection in host cells thrives in a vacuolated compartment, Salmonella Containing Vacuole (SCV), which sequentially acquires host endosomal and lysosomal markers. Long tubular structures, called as Salmonella induced filaments (SIFs), are known to be required for SCVs nutrient acquisition, membrane maintenance and stability. A tightly coordinated interactions involving prominent effector SifA and various host adapters PLEKHM1, PLEKHM2 and Rab GTPases govern SCV integrity and SIF formation. Here, we report for the first time, the functional regulation of SifA is modulated by its SUMOylation at lysine 11. S. Tm expressing lysine 11 mutant SifA (SifAK11R) is defective in intracellular proliferation due to compromised SIF formation and enhanced lysosomal acidification. Furthermore, murine competitive index experiments reveal defective in vivo proliferation and weakened virulence of SifAK11R mutant. Concisely, our results demonstrate that SUMO deficient SifA mutant nearly behaves like a SifA knockout strain which impacts PLEKHM2-M6PR mediated lysosomal acidification pathway. Thus, our results bring forth a novel S. Tm-host crosstalk mechanism involving host mediated effector SUMOylation critical for pathogenicity.

microbiology↗

X-linked adrenoleukodystrophy patient fibroblast-iPSC-derived astrocytes reveal phenotype-specific metabolic, inflammatory, and microRNA alterations

X-linked adrenoleukodystrophy (X-ALD) is an inherited progressive metabolic disorder caused by pathogenic variants in the ABCD1 gene, which leads to accumulation of very long chain fatty acids in body fluids and tissues including brain and spinal cord. In the absence of a clear genotype-phenotype correlation the molecular mechanisms of the severe cerebral adrenoleukodystrophy (cALD) and the milder adrenomyeloneuropathy (AMN) phenotypes remain unknown. Given our previous evidence of role of astrocytes in the neuroinflammatory response in X-ALD we investigated the metabolic and molecular profiles of astrocytes derived from induced pluripotent stem cells (iPSC). The iPSCs were in turn generated from skin fibroblasts from healthy controls and patients with AMN or cALD. AMN and cALD astrocytes exhibited lack of ABCD1 and accumulation of very long chain fatty acids, a hallmark of X-ALD disease. Further, cALD astrocytes harbor significantly higher phosphorylation of STAT3, increased Toll-like receptor expression and higher chemokine and cytokine expression. In this first report of miRNA sequencing in X-ALD astrocytes, we observed that miR-9 expression was associated with increasing disease severity phenotype. CRISPR-Cas9 knock-in of ABCD1ABCD1 gene expression differentially affected the expression of key molecular, metabolic and microRNA targets in AMN and cALD astrocytes. Extensive characterization of the AMN and cALD iPSC-derived astrocyte model demonstrates critical aspects of X-ALD inflammatory disease in response to ABCD1ABCD1 mutation and can be further utilized for exploring the contribution of astrocytes to differential inflammatory response in cALD.

neuroscience↗

External fertilization is orchestrated by a pH-regulated soluble adenylyl cyclase controlling sperm motility and chemotaxis

The reaction of CO2 with H2O to form HCO3- and H+ is one of the most important chemical equilibria in cells. In mammalian sperm, a soluble adenylyl cyclase (sAC) serves as cellular HCO3- sensor that conveys the equilibrium state via cAMP synthesis to cAMP-signaling molecules. The function of sAC and cAMP in non-mammalian sperm is largely unknown. Here, we identify sAC orthologs in sea urchin and salmon sperm that, surprisingly, are activated by alkaline pH rather than HCO3-. Two amino-acid residues required for HCO3- binding of mammalian sAC are lacking in pH-regulated sAC. Orthologs identified in ten other phyla are also lacking either one of these key residues, suggesting that pH control is widespread among non-mammalian metazoan. The pH-sensitive sAC controls several functions of sperm from external fertilizers. Upon spawning, alkalization triggers cAMP synthesis and, thereby, activates motility of quiescent sperm. Egg-derived chemoattractants also alkalize sperm and elevate cAMP, which then-modulates pacemaker HCN channels to trigger a chemotactic Ca2+ response. Finally, the sAC and the voltage- and cAMP-activated Na+/H+ exchanger sNHE mutually control each other. A picture of evolutionary significance is emerging: motility and sensory signaling of sperm from both internal and external fertilizers rely on cAMP, yet, their sAC is regulated by HCO3- or pHi, respectively. Acidification of aquatic habitats due to climate change may adversely affect pH-sensing by sAC and thereby sexual reproduction in the sea. Statement of significanceAdenylyl cyclases synthesize cAMP, a prominent cellular messenger. A bicarbonate-sensitive AC family member, soluble AC (sAC), is tied to the chemical equilibrium: H2O + CO2 {leftrightarrow} HCO3- (bicarbonate) + H+. The sAC is required for fertilization: Mammals lacking sAC are infertile and sperm immotile. We now identify a new sAC form in sperm of non-mammalian animals that reproduce in the sea. This novel sAC is activated at alkaline pH rather than bicarbonate. It controls sperm motility and chemotaxis. The switch from HCO3- to pH rests on substitution of two amino-acids, which represents an adaptation to aquatic environments low in bicarbonate. Acidification of aquatic habitats due to climate change may adversely affect sAC activity and, thereby, fertilization.

biophysics↗

Soluble adenylyl cyclase inhibition prevents human sperm functions essential for fertilization

Soluble adenylyl cyclase (sAC: ADCY10) is essential for activating dormant sperm. Studies of freshly dissected mouse sperm identified sAC as needed for initiating capacitation and activating motility. We now use an improved sAC inhibitor, TDI-10229, for a comprehensive analysis of sAC function in human sperm. Unlike dissected mouse sperm, human sperm are collected post-ejaculation, after sAC activity has already been stimulated. Even in ejaculated human sperm, TDI-10229 interrupts stimulated motility and capacitation, and it prevents acrosome reaction in capacitated sperm. At present, there are no non-hormonal, pharmacological methods for contraception. Because sAC activity is required post-ejaculation at multiple points during the sperms journey to fertilize the oocyte, sAC inhibitors define candidates for non-hormonal, on-demand contraceptives suitable for delivery via intravaginal devices in females.

pharmacology and toxicology↗

A precision virtual crossmatch decision support system for interpretation of ambiguous molecular HLA typing data

Virtual crossmatch (VXM) compares a transplant candidates unacceptable antigens to the HLA typing of the donor before an organ offer is accepted and, in selected cases, supplant a prospective physical crossmatch. However, deceased donor typing can be ambiguous, leading to uncertainty in compatibility prediction. We have developed a web application that utilizes ambiguous HLA molecular typing data to assist in VXM assessments. The application compares a candidates listed unacceptable antigens to computed probabilities of all possible two-field donor HLA alleles and UNOS antigens. The VIrtual CrossmaTch for mOleculaR HLA typing (VICTOR) tool can be accessed at http://www.transplanttoolbox.org/victor. We reanalyzed historical VXM cases where a transplant centers manual interpretation of molecular typing results influenced offer evaluation. We found that VICTORs automated interpretation of ambiguous donor molecular typing data would influence VXM decisions. Standardized interpretation of molecular typing data, if applied to the match run, could also change which offers are made. HLA typing ambiguity has been an underappreciated source of immunological risk in organ transplantation. The VICTOR tool can serve as a testbed for development of allocation policies with the aim of decreasing offers refused due to HLA incompatibility.

immunology↗