Biology subjects

Figueroa, J.

Publications and source records attributed to Figueroa, J..

3 recordsLinked to original sources

bioRxiv2024

Novel Library Assembly Technique for Developing Nanobodies Targeting IPNv VP2 Protein

Infectious pancreatic necrosis virus (IPNv) poses a significant threat to the global salmon farming industry, causing high mortality and economic losses. Given the limitations of traditional antibody therapies in aquaculture, we explored the development of nanobodies targeting the VP2 protein of IPNv. We developed a novel nanobody library generation method using a streamlined assembly protocol based on Type IIS restriction enzymes. This method enabled quick and efficient bacterial display library generation, and concatenated, multi-level cloning through an ingenious design in which the ligation of the first level generates a new restriction site that can be utilized in the subsequent cloning level, allowing for rapid transfer to other vectors. By combining this assembly approach with density gradient-based enrichment and high-throughput screening, we identified nanobodies that specifically recognize IPNvs VP2 protein. Notably, the P9 clone demonstrated high specificity for IPNv in immunofluorescence assays, highlighting its diagnostic potential. Our method not only accelerates nanobody library generation but also enhances its quality and adaptability, marking a significant advancement in enhancing the responsiveness of nanobody development platforms against emerging pathogen outbreaks.

molecular biology↗

bioRxiv2021

Rare copy number variants (CNVs) and breast cancer risk

BackgroundCopy number variants (CNVs) are pervasive in the human genome but potential disease associations with rare CNVs have not been comprehensively assessed in large datasets. We analysed rare CNVs in genes and non-coding regions for 86,788 breast cancer cases and 76,122 controls of European ancestry with genome-wide array data. ResultsGene burden tests detected the strongest association for deletions in BRCA1 (P= 3.7E-18). Nine other genes were associated with a p-value < 0.01 including known susceptibility genes CHEK2 (P= 0.0008), ATM (P= 0.002) and BRCA2 (P= 0.008). Outside the known genes we detected associations with p-values < 0.001 for either overall or subtype-specific breast cancer at nine deletion regions and four duplication regions. Three of the deletion regions were in established common susceptibility loci. ConclusionsThis is the first genome-wide analysis of rare CNVs in a large breast cancer case-control dataset. We detected associations with exonic deletions in established breast cancer susceptibility genes. We also detected suggestive associations with non-coding CNVs in known and novel loci with large effects sizes. Larger sample sizes will be required to reach robust levels of statistical significance.

genetics↗

bioRxiv2020

Africanized honeybees in Colombia exhibit high prevalence but low level of infestation of Varroa mites and low prevalence of pathogenic viruses

The global spread of the ectoparasitic mite Varroa destructor has promoted the spread and virulence of highly infectious honey bee viruses. This phenomenon is considered the leading cause for the increased number of colony losses experienced by the mite-susceptible European honey bee populations in the Northern Hemisphere. Most of the honey bee populations in Central and South America are Africanized honey bees, which are considered more resistant to Varroa compared to European honey bees. However, the relationship between Varroa levels and spread of honey bee viruses in Africanized honey bees remains unknown. In this study, we determined Varroa prevalence and infestation levels as well as the prevalence of seven major honey bee viruses in Africanized honey bees from three regions of Colombia. We found that although Varroa exhibited high prevalence (92%), its infestation levels were low (4.6%) considering that these populations never received acaricide treatments. We also detected four viruses in the three regions analyzed, but all hives were asymptomatic, and virus prevalence was considerably lower than those found in other countries with higher rates of mite-associated colony loss (DWV 19.88%, BQCV 17.39%, SBV 23.4 %, ABPV 10.56%). Our findings indicate that AHBs possess natural resistance to Varroa that does not prevent the spread of this parasite among their population, but restrains mite population growth and suppresses the prevalence and pathogenicity of mite-associated viruses.

pathology↗