Transcriptome, Genetic Transformation and Micropropagation: Some Biotechnology Strategies to Diminish Water Stress Caused by Climate Change in Sugarcane

Global climate change caused by natural processes results in major environmental issues that affect the world. Climate variability results in changes that cause water stress in plants. Sugarcane is a tropical grass C4, perennial and a multi-purpose industrial cash crop which serves as the main source of raw material for the production of sugar and biofuel. Farmers face the challenge to provide biotech alternatives with potential benefits and minimize potential adverse impacts on sugarcane’s production. In order to find biotechnology strategies to diminish the impact of climate change, our laboratory teamworks with micropropagation, transcriptome and genetic transformation of sugarcane using the var. MEX69290. In the transcriptome of sugarcane, a total of 536 and 750 genes were differentially regulated under normal and water stress treatment respectively, of which key genes were selected to be inserted into sugarcane for tolerance to abiotic stress. Regarding results of micropropagation, it was concluded that the continuous immersion propagation system was the best culture strategy. This may be as result of the elimination of gelling agent, which additionally helps reduce production costs

OVEREXPRESSION OF WUSCHEL IMPROVES THE INDUCTION OF EMBRYOGENIC CALLUS IN SCALPS OF MUSA ACUMINATA L. AAA, CV. “GRAND NAIN”

Background: During the last few years the home box transcription factor WUSCHEL (WUS) has been shown to cause dedifferentiation when expressed on somatic cells followed by a production of new stem cells that can lead to somatic embryogenesis or organogenesis. WUS has been shown to promote the transition from a vegetative to an embryogenic state when overexpressed. Objective/Hypothesis. The genetic in vitro transformation of meristematic tissue of Musa acuminata L. AAA, cv. “Grand Nain” was carried out using a heterologous gene WUSCHEL from Arabidopsis thaliana, via vacuum infiltration with Agrobacterium tumefaciens, to establish and ascertain if its expression modifies the progression of the explants to the embryogenesis process and or reduces the time needed for in vitro embryogenic induction phase. Methodology: Explants of proliferating shoot meristems, named “scalps”, of Musa acuminata L. AAA, cv. “Grand Nain” was transformed with WUS gene under the control of promoter GAL4, inducible by 17b-estradiol. The effect of steroid 17b-estradiol (b-Est) and homobrassinolide (HomoBra) on the in vitro somatic embryogenesis induction phase of non-transformed banana scalps was investigated. Results: The successful transformation of the explants was confirmed by PCR, for the transferred neomycin phosphotransferase II (NPTII) and the WUS gene. In addition, the expression of the red fluorescent protein (RFP) for the corresponding transferred reporter gene was verified by fluorescence microscopy in proliferated transformed tissues. Besides, the transformed tissue response to the induction of embryogenesis with either b-Est and/or HomoBra, inducers of the transgene were investigated. Implications: The improvement of the process of somatic embryogenesis in this way, generates a more effective and productive study model in a short time. Conclusions: WUS can promote the meristematic tissue-to-embryonic transition, and eventually somatic embryo formation, suggesting that the homeodomain protein can play a critical role during embryogenesis

Subcutaneous anti-COVID-19 hyperimmune immunoglobulin for prevention of disease in asymptomatic individuals with SARS-CoV-2 infection: a double-blind, placebo-controlled, randomised clinical trialResearch in context

Summary: Background: Anti-COVID-19 hyperimmune immunoglobulin (hIG) can provide standardized and controlled antibody content. Data from controlled clinical trials using hIG for the prevention or treatment of COVID-19 outpatients have not been reported. We assessed the safety and efficacy of subcutaneous anti-COVID-19 hyperimmune immunoglobulin 20% (C19-IG20%) compared to placebo in preventing development of symptomatic COVID-19 in asymptomatic individuals with SARS-CoV-2 infection. Methods: We did a multicentre, randomized, double-blind, placebo-controlled trial, in asymptomatic unvaccinated adults (≥18 years of age) with confirmed SARS-CoV-2 infection within 5 days between April 28 and December 27, 2021. Participants were randomly assigned (1:1:1) to receive a blinded subcutaneous infusion of 10 mL with 1 g or 2 g of C19-IG20%, or an equivalent volume of saline as placebo. The primary endpoint was the proportion of participants who remained asymptomatic through day 14 after infusion. Secondary endpoints included the proportion of individuals who required oxygen supplementation, any medically attended visit, hospitalisation, or ICU, and viral load reduction and viral clearance in nasopharyngeal swabs. Safety was assessed as the proportion of patients with adverse events. The trial was terminated early due to a lack of potential benefit in the target population in a planned interim analysis conducted in December 2021. ClinicalTrials.gov registry: NCT04847141. Findings: 461 individuals (mean age 39.6 years [SD 12.8]) were randomized and received the intervention within a mean of 3.1 (SD 1.27) days from a positive SARS-CoV-2 test. In the prespecified modified intention-to-treat analysis that included only participants who received a subcutaneous infusion, the primary outcome occurred in 59.9% (91/152) of participants receiving 1 g C19-IG20%, 64.7% (99/153) receiving 2 g, and 63.5% (99/156) receiving placebo (difference in proportions 1 g C19-IG20% vs. placebo, −3.6%; 95% CI -14.6% to 7.3%, p = 0.53; 2 g C19-IG20% vs placebo, 1.1%; −9.6% to 11.9%, p = 0.85). None of the secondary clinical efficacy endpoints or virological endpoints were significantly different between study groups. Adverse event rate was similar between groups, and no severe or life-threatening adverse events related to investigational product infusion were reported. Interpretation: Our findings suggested that administration of subcutaneous human hyperimmune immunoglobulin C19-IG20% to asymptomatic individuals with SARS-CoV-2 infection was safe but did not prevent development of symptomatic COVID-19. Funding: Grifols