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1.
Curr Biol ; 33(14): 3056-3064.e5, 2023 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-37453426

RESUMEN

Identified through forward genetics, spe-9 was the first gene to be identified in C. elegans as necessary for fertilization.1 Since then, genetic screens in C. elegans have led to the identification of nine additional sperm genes necessary for fertilization (including spe-51 reported by Mei et al.2 and the spe-36 gene reported here).3,4,5,6,7,8,9 This includes spe-45, which encodes an immunoglobulin-containing protein similar to the mammalian protein IZUMO1, and spe-42 and spe-49, which are homologous to vertebrate DCST2 and DCST1, respectively.4,7,8,10,11,12,13 Mutations in any one of these genes result in healthy adult animals that are sterile. Sperm from these mutants have normal morphology, migrate to and maintain their position at the site of fertilization in the reproductive tract, and make contact with eggs but fail to fertilize the eggs. This same phenotype is observed in mammals lacking Izumo1, Spaca6, Tmem95, Sof1, FIMP, or Dcst1 and Dcst2.10,14,15,16,17,18,19 Here we report the discovery of SPE-36 as a sperm-derived secreted protein that is necessary for fertilization. Mutations in the Caenorhabditis elegans spe-36 gene result in a sperm-specific fertilization defect. Sperm from spe-36 mutants look phenotypically normal, are motile, and can migrate to the site of fertilization. However, sperm that do not produce SPE-36 protein cannot fertilize. Surprisingly, spe-36 encodes a secreted EGF-motif-containing protein that functions cell autonomously. The genetic requirement for secreted sperm-derived proteins for fertilization sheds new light on the complex nature of fertilization and represents a paradigm-shifting discovery in the molecular understanding of fertilization.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Masculino , Caenorhabditis elegans/fisiología , Proteínas del Esperma , Factor de Crecimiento Epidérmico/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Semen/metabolismo , Espermatozoides/fisiología , Fertilización , Mamíferos
2.
Trials ; 23(1): 932, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36348476

RESUMEN

BACKGROUND: COVID-19 poses a global health challenge with more than 325 million cumulative cases and above 5 million cumulative deaths reported till January 17, 2022, by the World Health Organization. Several potential treatments to treat COVID-19 are under clinical trials including antivirals, steroids, immunomodulators, non-specific IVIG, monoclonal antibodies, and passive immunization through convalescent plasma. The need to produce anti-COVID-19 IVIG therapy must be continued, alongside the current treatment modalities, considering the virus is still mutating into variants of concern. In this context, as the present study will exploit pooled diversified convalescent plasma collected from recovered COVID-19 patients, the proposed hyperimmune Anti-COVID-19 intravenous immunoglobulin (C-IVIG) therapy would be able to counter new infectious COVID-19 variants by neutralizing the virus particles. After the successful outcome of the phase I/II clinical trial of C-IVIG, the current study aims to further evaluate the safety and efficacy of single low dose C-IVIG in severe COVID-19 patients for its phase II/III clinical trial. METHODS: This is a phase II/III, adaptive, multi-center, single-blinded, randomized controlled superiority trial of SARS-CoV-2 specific polyclonal IVIG (C-IVIG). Patients fulfilling the eligibility criteria will be block-randomized using a sealed envelope system to receive either 0.15 g/Kg C-IVIG with standard of care (SOC) or standard of care alone in 2:1 ratio. The patients will be followed-up for 28 days to assess the primary and secondary outcomes. DISCUSSION: This is a phase II/III clinical trial evaluating safety and efficacy of hyperimmune anti-COVID-19 intravenous immunoglobulin (C-IVIG) in severe COVID-19 patients. This study will provide clinical evidence to use C-IVIG as one of the first-line therapeutic options for severe COVID-19 patients. TRIAL REGISTRATION: Registered at clinicaltrial.gov with NCT number NCT04891172 on May 18, 2021.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Infecciones por Coronavirus , Neumonía Viral , Humanos , SARS-CoV-2 , Betacoronavirus , Neumonía Viral/tratamiento farmacológico , Inmunoglobulinas Intravenosas/efectos adversos , Infecciones por Coronavirus/tratamiento farmacológico , Pandemias , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Sueroterapia para COVID-19
4.
EClinicalMedicine ; 36: 100926, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34109306

RESUMEN

BACKGROUND: Hyperimmune anti-COVID-19 Intravenous Immunoglobulin (C-IVIG) is an unexplored therapy amidst the rapidly evolving spectrum of medical therapies for COVID-19 and is expected to counter the three most life-threatening consequences of COVID-19 including lung injury by the virus, cytokine storm and sepsis. METHODS: A single center, phase I/II, randomized controlled, single-blinded trial was conducted at Dow University of Health Sciences, Karachi, Pakistan. Participants were COVID-19 infected individuals, classified as either severely or critically ill with Acute Respiratory Distress Syndrome (ARDS). Participants were randomized through parallel-group design with sequential assignment in a 4:1 allocation to either intervention group with four C-IVIG dosage arms (0.15, 0.20, 0.25, 0.30 g/kg), or control group receiving standard of care only (n = 10). Primary outcomes were 28-day mortality, patient's clinical status on ordinal scale and Horowitz index (HI), and were analysed in all randomized participants that completed the follow-up period (intention-to-treat population). The trial was registered at clinicaltrials.gov (NCT04521309). FINDINGS: Fifty participants were enrolled in the study from June 19, 2020 to February 3, 2021 with a mean age of 56.54±13.2 years of which 22 patients (44%) had severe and 28 patients (56%) had critical COVID-19. Mortality occurred in ten of 40 participants (25%) in intervention group compared to six of ten (60%) in control group, with relative risk reduction in intervention arm I (RR, 0.333; 95% CI, 0.087-1.272), arm II (RR, 0.5; 95% CI, 0.171-1.463), arm III (RR, 0.167; 95% CI, 0.024-1.145), and arm IV (RR, 0.667; 95% CI, 0.268-1.660). In intervention group, median HI significantly improved to 359 mmHg [interquartile range (IQR) 127-400, P = 0.009)] by outcome day, while the clinical status of intervention group also improved as compared to control group, with around 15 patients (37.5%) being discharged by 7th day with complete recovery. Additionally, resolution of chest X-rays and restoration of biomarkers to normal levels were also seen in intervention groups. No drug-related adverse events were reported during the study. INTERPRETATION: Administration of C-IVIG in severe and critical COVID-19 patients was safe, increased the chance of survival and reduced the risk of disease progression. FUNDING: Higher Education Commission (HEC), Pakistan (Ref no. 20-RRG-134/RGM/R&D/HEC/2020).

5.
Immunotherapy ; 13(5): 397-407, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33557591

RESUMEN

Background: This study assesses the feasibility of producing hyperimmune anti-COVID-19 intravenously administrable immunoglobulin (C-IVIG) from pooled convalescent plasma (PCP) to provide a safe and effective passive immunization treatment option for COVID-19. Materials & methods: PCP was fractionated by modified caprylic acid precipitation followed by ultrafiltration/diafiltration to produce hyperimmune C-IVIG. Results: In C-IVIG, the mean SARS-CoV-2 antibody level was found to be threefold (104 ± 30 cut-off index) that of the PCP (36 ± 8.5 cut-off index) and mean protein concentration was found to be 46 ± 3.7 g/l, comprised of 89.5% immunoglobulins. Conclusion: The current method of producing C-IVIG is feasible as it uses locally available PCP and simpler technology and yields a high titer of SARS-CoV-2 antibody. The safety and efficacy of C-IVIG will be evaluated in a registered clinical trial (NCT04521309).


Asunto(s)
Anticuerpos Antivirales/aislamiento & purificación , COVID-19/sangre , Inmunoglobulinas Intravenosas/aislamiento & purificación , SARS-CoV-2/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , COVID-19/terapia , Caprilatos/química , Fraccionamiento Químico , Humanos , Inmunización Pasiva , Inmunoglobulinas Intravenosas/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico , Sueroterapia para COVID-19
6.
Trials ; 21(1): 905, 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33138867

RESUMEN

OBJECTIVES: The aim of this trial is to investigate the safety and clinical efficacy of passive immunization therapy through Hyperimmune anti-COVID-19 Intravenous Immunoglobulin (C-IVIG: 5% liquid formulation), on severe and critically ill patients with COVID-19. TRIAL DESIGN: This is a phase I/II single centre, randomised controlled, single-blinded, superiority trial, through parallel-group design with sequential assignment. Participants will be randomised either to receive both C-IVIG and standard care or only standard care (4:1). PARTICIPANTS: The study is mono-centric with the participants including COVID19 infected individuals (positive SARS-CoV-2 PCR on nasopharyngeal and/or oropharyngeal swabs) admitted in institute affiliated with Dow University Hospital, Dow University of Health Sciences, Karachi, Pakistan. Consenting patients above 18 years that are classified by the treating physician as severely ill i.e. showing symptoms of COVID-19 pneumonia; dyspnea, respiratory rate ≥30/min, blood oxygen saturation ≤93%, PaO2/FiO2 <300, and lung infiltrates >50% on CXR; or critically ill i.e. respiratory failure, septic shock, and multiple organ dysfunction or failure. Patients with reported IgA deficiency, autoimmune disorder, thromboembolic disorder, and allergic reaction to immunoglobulin treatment were excluded from study. Similarly, pregnant females, patients requiring two or more inotropic agents to maintain blood pressure and patients with acute or chronic kidney injury/failure, were also excluded from the study. INTERVENTION AND COMPARATOR: The study consists of four interventions and one comparator arm. All participants receive standard hospital care which includes airway support, anti-viral medication, antibiotics, fluid resuscitation, hemodynamic support, steroids, painkillers, and anti-pyretics. Randomised test patients will receive single dose of C-IVIG in following four dosage groups: Group 1: 0.15g/Kg with standard hospital care Group 2: 0.2g/Kg with standard hospital care Group 3: 0.25g/Kg with standard hospital care Group 4: 0.3g/Kg with standard hospital care Group 5 (comparator) will receive standard hospital care only MAIN OUTCOMES: The primary outcomes are assessment and follow-up of participants to observe 28-day mortality and, • the level and duration of assisted ventilation during hospital stay, • number of days to step down (shifting from ICU to isolation ward), • number of days to hospital discharge, • adverse events (Kidney failure, hypersensitivity with cutaneous or hemodynamic manifestations, aseptic meningitis, hemolytic anemia, leuko-neutropenia, transfusion related acute lung injury (TRALI)) during hospital stay, • change in C-Reactive Protein (CRP) levels, • change in neutrophil lymphocyte ratio to monitor inflammation. RANDOMISATION: Consenting participants who fulfill the criteria are allocated to either intervention or comparator arm with a ratio of 4:1, using sequentially numbered opaque sealed envelope simple randomization method. The participant allocated for intervention will be sequentially assigned dosage group 1-4 in ascending order. Participants will not be recruited in the next dosage group before a set number of participants in one group (10) are achieved. BLINDING (MASKING): Single blinded study, with participants blinded to allocation. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): Total 50 patients are randomised. The intervention arms consist of 40 participants divided in four groups of 10 participants while the comparator group consists of 10 patients. TRIAL STATUS: Current version of the protocol is "Version 2" dated 29th September, 2020. Participants are being recruited. Recruitment started on June, 2020 and is estimated to primarily end on January, 2021. TRIAL REGISTRATION: This trial was registered at ClinicalTrials.gov, NCT04521309 on 20 August 2020 and is retrospectively registered. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1).


Asunto(s)
Infecciones por Coronavirus/terapia , Inmunización Pasiva/métodos , Inmunoglobulinas Intravenosas , Neumonía Viral/terapia , Adulto , Betacoronavirus/aislamiento & purificación , COVID-19 , Enfermedad Crítica/terapia , Femenino , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunoglobulinas Intravenosas/efectos adversos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/efectos adversos , Masculino , Pandemias , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Sueroterapia para COVID-19
7.
Pak J Pharm Sci ; 33(4(Supplementary)): 1855-1861, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33612470

RESUMEN

Recently, probiotic yeasts have become an interesting topic of research all over the world. Saccharomyces cerevisiae is well proven probiotic yeast against several gastrointestinal diseases. Current study aimed to explore the probiotic potential and antibacterial properties of Saccharomyces strains isolated from fresh lychee fruits available in local markets of Karachi, Pakistan. Probiotic potential and antibacterial activity of locally isolated probiotic yeast strains (named as S. cerevisiae BEL 1 and S. cerevisiae BEL 9) was studied against gastrointestinal pathogens using standard in vitro screening methods. Comparative analysis was also carried out with commercially available S. boulardii probiotic preparations. Furthermore, for probiotic potential, all the studied yeast strains were exposed to various stress conditions inherent of gastrointestinal tract i.e., thermo tolerance, pH tolerance, bile salts survivability and osmo-tolerance. Isolated strains (BEL 1 and BEL 9) were able to tolerate at the temperatures (40oC and 45oC), moreover survived in the presence of gastric juices, extreme bile salt concentrations (range 0.5%-2%) and different osmotic stress conditions (1M and 1.5 M NaCl). Optimal growth was observed at 37oC. Similar growth pattern and viability of BEL 1 and 9 was found for most of the stress conditions, when compared with the commercially available strains of S. boulardii. Therefore, isolated yeast strains BEL 1 and 9 will be considered as a potential bio-therapeutic agent because of the promising probiotic potential.


Asunto(s)
Frutas/microbiología , Litchi/microbiología , Probióticos/administración & dosificación , Saccharomyces/aislamiento & purificación , Tracto Gastrointestinal/microbiología , Humanos , Pakistán
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