Biology subjects

Gulzar, N.

Publications and source records attributed to Gulzar, N..

4 recordsLinked to original sources

bioRxiv2024

A pipeline for facile cloning of antibody Fv domains and their expression, purification, and characterization as recombinant His-tagged IgGs

We report a functional pipeline for facile conversion of variable Fv domains, typically discovered in antibody discovery programs, into chimeric monoclonal antibodies (mAbs). Often, in initial screenings, a set of candidate mAbs is produced in small volumes and purified from supernatant for testing. Our pipeline also simplifies purification of mAbs by using an extended histidine tag (His-10) fused to the C-terminus of the light chain. Both the length of the His-10 and its location have been shown to affect the efficacy of mAb purification using an inexpensive nickel-based resin at neutral pH. Our antibody cloning and purification pipeline, when followed together with detection and affinity measurements, can be smoothly incorporated into an antibody discovery workflow.

immunology↗

bioRxiv2022

CD4 binding-site antibodies induced by a subtype B HIV-1 envelope trimer

In the last decade considerable advances have been made towards the design of HIV-1 vaccines that induce neutralizing antibodies (NAbs). Despite the progress, no vaccine is able to consistently elicited broadly neutralizing antibodies (bNAbs). Here we present a case study of a rabbit that was immunized with a subtype B native like envelope glycoprotein (Env) trimer, AMC016 SOSIP.v4.2, with a dense and intact glycan shield, followed by a trivalent combination of subtype B trimers. After the priming phase serum from this animal neutralized several heterologous subtype B neutralization resistant (tier 2) viruses. Subsequent immunization with the trivalent combination of subtype B trimers further increased the breadth and potency of the NAb response. EM based polyclonal epitope mapping revealed that a cross reactive CD4 binding-site (CD4bs) antibody response, that was present after priming with the monovalent trimer and boosting with the trivalent combination, was most likely responsible for the broad neutralization. While anecdotal, this study provides proof-of-concept that native-like Env trimers are capable of inducing CD4bs-directed bNAb responses and should guide efforts to improve the consistency with which such responses are generated.

immunology↗

bioRxiv2021

BioCompute Objects to communicate a viral detection pipeline with potential for use in a regulatory environment

The volume of nucleic acid sequence data has exploded in recent years, and with it, the challenge of finding and transforming relevant data into meaningful information. Processing the abundance of data can require a dynamic ecosystem of customized tools. As analysis pipelines become more complex, there is an increased difficulty in communicating analysis details in a way that is understandable yet of sufficient detail to make informed decisions about results or repeat the analysis. This may be of particular interest to institutions and private companies that need to communicate complex computations in a regulatory environment. To meet this need for standard reporting, the open source BioCompute framework was developed as a standardized mechanism for communicating the details of an analysis in a concise and organized way, and other tools and interfaces were subsequently developed according to the standard. The goal of BioCompute is to streamline the process of communicating computational analyses. Reports that conform to the BioCompute standard are called BioCompute Objects (BCOs). Here, a comprehensive suite of BCOs is presented, representing interconnected elements of a computation that is modeled after those that might be found in a regulatory submission, but which can be shared publicly. Because BCOs are human and machine readable, they can be displayed in customized ways to further improve their utility, and an example of a collapsible format is shown. The work presented here serves as a real world implementation that imitates actual submissions, providing concrete examples. As an example, a pipeline designed to identify viral contaminants in biological manufacturing, such as for vaccines, is developed and rigorously tested to establish a rate of false positive detection, and is described in a BCO report. That pipeline relies on a specially curated database for alignment, and a set of synthetic reads for testing, both of which are also descriptively packaged in their own BCOs. All of the sufficiently complex processes associated with this analysis are therefore represented as BCOs that can be cross-referenced, demonstrating the modularity of BCOs, their ability to organize tremendous complexity, and their use in a lifelike regulatory environment.

bioinformatics↗

bioRxiv2018

Baseline human gut microbiota profile in healthy people and standard reporting template

A comprehensive knowledge of the types and ratios of microbes that inhabit the healthy human gut is necessary before any kind of pre-clinical or clinical study can be performed that attempts to alter the microbiome to treat a condition or improve therapy outcome. To address this need we present an innovative scalable comprehensive analysis workflow, a healthy human reference microbiome list and abundance profile (GutFeelingKB), and a novel Fecal Biome Population Report (FecalBiome) with clinical applicability. GutFeelingKB provides a list of 157 organisms (8 phyla, 18 classes, 23 orders, 38 families, 59 genera and 109 species) that forms the baseline biome and therefore can be used as healthy controls for studies related to dysbiosis. The incorporation of microbiome science into routine clinical practice necessitates a standard report for comparison of an individuals microbiome to the growing knowledgebase of \"normal\" microbiome data. The FecalBiome and the underlying technology of GutFeelingKB address this need. The knowledgebase can be useful to regulatory agencies for the assessment of fecal transplant and other microbiome products, as it contains a list of organisms from healthy individuals. In addition to the list of organisms and abundances the study also generated a list of contigs of metagenomics dark matter. In this study, metagenomic dark matter represents sequences that cannot be mapped to any known sequence but can be assembled into contigs of 10,000 nucleotides or higher. These sequences can be used to create primers to study potential novel organisms. All data is freely available from https://hive.biochemistry.gwu.edu/gfkb and NCBIs Short Read Archive.

microbiology↗