Mammalian cell expressed recombinant trimeric spike protein is a potent vaccine antigen and confers near-complete protection against SARS-CoV-2 infection in Hamster.

Numerous vaccine candidates have emerged in the fight against SARS-CoV-2, yet the challenges posed by viral evolution and the evasion of vaccine-induced immunity persist. The development of broadly protective vaccines is essential in countering the threat posed by variants of concern (VoC) capable of eluding existing vaccine defenses. Among the diverse SARS-CoV-2 vaccine candidates, detailed characterization of those based on the expression of the entire spike protein in mammalian cells have been limited. In our study, we engineered a recombinant prefusion-stabilized trimeric spike protein antigen, IMT-CVAX, encoded by the IMT-C20 gene. This antigen was expressed utilizing a suspension mammalian cell line (CHO-S). The establishment of a stable cell line expressing IMT-CVAX involved the integration of the gene into the CHO genome, followed by the expression, purification, and characterization of the protein. To gauge the vaccine potential of adjuvanted IMT-CVAX, we conducted assessments in small animals. Analyses of blood collected from immunized animals included measurements of anti-spike IgG, SARS-CoV-2 neutralization, and responses from GC-B and Tfh cells. Furthermore, the protective efficacy of IMT-CVAX was evaluated using a Hamster challenge model. Our findings indicate that adjuvanted IMT-CVAX elicits an excellent immune response in both mice and hamsters. Notably, sera from animals immunized with IMT-CVAX effectively neutralize a diverse range of SARS-CoV-2 variants. Moreover, IMT-CVAX immunization conferred complete protection to hamsters against SARS-CoV-2 infection. In hACE2 transgenic mice, IMT-CVAX vaccination induced a robust response from GC-B and Tfh cells. Based on our preclinical model assessments, adjuvanted IMT-CVAX emerges as a highly efficacious vaccine candidate. This protein-subunit-based vaccine exhibits promise for clinical development, offering an affordable solution for both primary and heterologous immunization against SARS-CoV-2 variants.

Molecular characterization and forensic relevance of the autosomal STRs for the population of North Indian geographical province Himachal Pradesh, India.

Keeping in view the diverse demography of India, present study was undertaken to explore the molecular characterization and forensic relevance of 20 autosomal STRs for the highly diverse population of north Indian state Himachal Pradesh. 724 unrelated individuals from the admixed population of Himachal Pradesh were undertaken for present study and 20 autosomal STRs used to explore genomic diversity of studied population. A total of 270 different alleles along with 13.5 alleles per locus were observed. The allele 8 of the locus TPOX was observed as the most frequent allele. Observed heterozygosity ranged from 0.677 to 0.898, which supported wide range of selection of the unrelated individuals for this study. Combined power of discrimination, power of exclusion, matching probability and paternity index were observed as 1, 0.9999999958, 3.9 × 10-26 and 2.3 × 108 respectively, across the studied loci. In the population differentiation test, studied population showed genetic relatedness with Indian population rather than the populations of West, North and North east countries. Present study deciphered the novel autosomal STR data, which could be useful for the forensic application and population genetic studies.

Control of Locomotory Behavior of Caenorhabditis elegans by the Immunoglobulin Superfamily Protein RIG-3.

Cell surface immunoglobulin superfamily (IgSF) proteins play important roles in the development and function of the nervous system . Here we define the role of a Caenorhabditis elegans IgSF protein, RIG-3, in the function of the AVA command interneuron. This study reveals that RIG-3 regulates the abundance of the glutamate receptor subunit, GLR-1, in the AVA command interneuron and also regulates reversal behavior in C. elegans The mutant strain lacking rig-3 (rig-3 (ok2156)) shows increased reversal frequency during local search behaviors. Genetic and behavioral experiments suggest that RIG-3 functions through GLR-1 to regulate reversal behavior. We also show that the increased reversal frequency seen in rig-3 mutants is dependent on the increase in GLR-1 abundance at synaptic inputs to AVA, suggesting that RIG-3 alters the synaptic strength of incoming synapses through GLR-1 Consistent with the imaging experiments, altered synaptic strength was also reflected in increased calcium transients in rig-3 mutants when compared to wild-type control animals. Our results further suggest that animals lacking rig-3 show increased AVA activity, allowing the release of FLP-18 neuropeptide from AVA, which is an activity-dependent signaling molecule. Finally, we show that FLP-18 functions through the neuropeptide receptor, NPR-5, to modulate reversal behavior in C. elegans.

FLP-18 Functions through the G-Protein-Coupled Receptors NPR-1 and NPR-4 to Modulate Reversal Length in Caenorhabditis elegans.

Animal behavior is critically dependent on the activity of neuropeptides. Reversals, one of the most conspicuous behaviors in Caenorhabditis elegans, plays an important role in determining the navigation strategy of the animal. Our experiments on hermaphrodite C. elegans show the involvement of a neuropeptide FLP-18 in modulating reversal length in these hermaphrodites. We show that FLP-18 controls the reversal length by regulating the activity of AVA interneurons through the G-protein-coupled neuropeptide receptors, NPR-4 and NPR-1. We go on to show that the site of action of these receptors is the AVA interneuron for NPR-4 and the ASE sensory neurons for NPR-1. We further show that mutants in the neuropeptide, flp-18, and its receptors show increased reversal lengths. Consistent with the behavioral data, calcium levels in the AVA neuron of freely reversing C. elegans were significantly higher and persisted for longer durations in flp-18, npr-1, npr-4, and npr-1 npr-4 genetic backgrounds compared with wild-type control animals. Finally, we show that increasing FLP-18 levels through genetic and physiological manipulations causes shorter reversal lengths. Together, our analysis suggests that the FLP-18/NPR-1/NPR-4 signaling is a pivotal point in the regulation of reversal length under varied genetic and environmental conditions.SIGNIFICANCE STATEMENT In this study, we elucidate the circuit and molecular machinery required for normal reversal behavior in hermaphrodite Caenorhabditis elegans We delineate the circuit and the neuropeptide receptors required for maintaining reversal length in C. elegans Our work sheds light on the importance of a single neuropeptide, FLP-18, and how change in levels in this one peptide could allow the animal to change the length of its reversal, thereby modulating how the C. elegans explores its environment. We also go on to show that FLP-18 functions to maintain reversal length through the neuropeptide receptors NPR-4 and NPR-1. Our study will allow for a better understanding of the complete repertoire of behaviors shown by freely moving animals as they explore their environment.

Regulation of WNT Signaling at the Neuromuscular Junction by the Immunoglobulin Superfamily Protein RIG-3 in Caenorhabditis elegans.

Perturbations in synaptic function could affect the normal behavior of an animal, making it important to understand the regulatory mechanisms of synaptic signaling. Previous work has shown that in Caenorhabditis elegans an immunoglobulin superfamily protein, RIG-3, functions in presynaptic neurons to maintain normal acetylcholine receptor levels at the neuromuscular junction (NMJ). In this study, we elucidate the molecular and functional mechanism of RIG-3. We demonstrate by genetic and BiFC (Bi-molecular Fluorescence Complementation) assays that presynaptic RIG-3 functions by directly interacting with the immunoglobulin domain of the nonconventional Wnt receptor, ROR receptor tyrosine kinase (RTK), CAM-1, which functions in postsynaptic body-wall muscles. This interaction in turn inhibits Wnt/LIN-44 signaling through the ROR/CAM-1 receptor, and allows for maintenance of normal acetylcholine receptor, AChR/ACR-16, levels at the neuromuscular synapse. Further, this work reveals that RIG-3 and ROR/CAM-1 function through the ß-catenin/HMP-2 at the NMJ. Taken together, our results demonstrate that RIG-3 functions as an inhibitory molecule of the Wnt/LIN-44 signaling pathway through the RTK, CAM-1.

Antioxidant activity and protective effect against plasmid DNA strand scission of leaf, bark, and heartwood extracts from Acacia catechu.

UNLABELLED: The antioxidant activity of methanol extract/fractions of leaf, bark, and heartwood of Acacia catechu was evaluated by various antioxidant assays, including free radical, superoxide and hydroxyl radical, reducing power, metal ion chelation, as well as hydroxyl radical induced DNA strand scission. The leaf, bark, and heartwood powder was extracted in methanol and the lyophilized methanol extract was fractionated with different solvents in the order of increasing polarity. The results indicate that ethyl acetate fraction of heartwood has the highest antioxidant capacities, presenting lower EC(50) values particularly in free radical scavenging activity, including DPPH radicals (4.76 ± 0.14 µg/mL), superoxide anions (26.21 ± 0.79 µg/mL), and hydroxyl radicals (33.69 ± 1.42 µg/mL), in direct assay systems. Reducing power was also highest in ethyl acetate fraction of heartwood (EC(50) of 79.05 ± 1.02 µg/mL). As for the chelating power on ferrous ions, leaf extract was more effective than bark and heartwood extracts. Furthermore, the ethyl acetate and acetone fractions of heartwood significantly protected pBR322 supercoiled plasmid DNA against strand scission induced by hydroxyl radicals in a Fenton's reaction mixture. PRACTICAL APPLICATION: The present investigation suggests that the three organs of A. catechu differ significantly in their antioxidant potential as seen in the DPPH radical scavenging assay, reducing power assay, metal ion chelating assay, superoxide radical scavenging assay and hydroxyl radical scavenging assay. Further, our results showed that crude methanol extract and ethyl acetate fraction of heartwood of A. catechu might have a good potential as a source for natural health products due to its antioxidant and DNA protective activities.

Nitric oxide: lifesaving measure for pulmonary vasospasm after modified Blalock-Taussig shunt.

Pulmonary vasospasm and hypertension may occur after repair or palliation of congenital cardiac defects, and can be fatal in spite of conventional treatment. Nitric oxide has been shown to improve pulmonary hypertension unresponsive to conventional measures after a variety of repairs, but use has infrequently been reported after palliative systemic to pulmonary artery shunts. We report a case of pulmonary hypertension and life threatening desaturation after a modified Blalock-Taussig shunt that responded rapidly to inhaled nitric oxide. Clinical use, further study, and prospective analysis of prophylactic use of nitric oxide appear warranted.