J. Pharm. Pharmacogn. Res., vol. 10, no. 3, pp. 429-444, May-June 2022.
DOI: https://doi.org/10.56499/jppres21.1262_10.3.429
Original Article
Molecular characterization and prediction of B-cell epitopes for the development of SARS-CoV-2 vaccine through bioinformatics approach
[Caracterización molecular y predicción de epítopos de células B para el desarrollo de una vacuna contra el SARS-CoV-2 mediante un enfoque bioinformático]
Aamir Shehzad1, Martia Rani Tacharina1, Suryo Kuncorojakti2 , Hafiz Ishfaq Ahmad3, Rofiqul A’la1, Andi Yasmin Wijaya4, Wiwiek Tyasningsih5, Fedik Abdul Rantam1,4*
1Virology and Immunology Laboratory, Department of Microbiology, Faculty of Veterinary Medicine, Airlangga University, Surabaya, East Java, 60115, Indonesia.
2Division of Veterinary Anatomy, Department of Veterinary Science, Faculty of Veterinary Medicine Airlangga University, Surabaya, East Java, 60115, Indonesia.
3Department of Animal Breeding and Genetics, University of Veterinary and Animal Sciences, Lahore, Pakistan.
4Research Center for Vaccine Technology and Development, Institute of Tropical Disease, Universitas Airlangga, Surabaya, East Java, 60115 Indonesia.
5Bacteriology and Mycology Laboratory, Department of Microbiology, Faculty of Veterinary Medicine, Airlangga University, Surabaya, East Java, 60132, Indonesia.
*E-mail: fedik-a-r@fkh.unair.ac.id
Abstract
Context: The SARS-CoV-2 virus is the cause of the COVID-19 pandemic, which is a severe public health crisis worldwide.Aims: To analyze the SARS-CoV-2 isolates of Surabaya and predict ORF1ab polyprotein epitopes through the bioinformatics approach for vaccine candidate development.
Methods: Three genomic sequences of Surabaya isolates were obtained from the GISAID, NCBI and PDB Gen-bank databases and MEGA-11 software were used to understand the transformations in the isolates. The IEDB and VaxiJen, AllerTop, and ToxinPred web servers were used to predict B-cell epitopes and analyze their antigenicity, non-allergenicity, non-toxicity, respectively. Moreover, these epitopes were linked by EAAAK for 3D modeling, refinement, and validation through Swiss-Model, Galaxy Refine, and RAMPAGE web tools.
Results: The Surabaya isolates, RSDS-RCVTD-UNAIR-49-A, 54-A, and 42-A, had 10, 20, and 16 mutations in nucleotides and depicted a phylogenetically close relationship to isolates of Egypt, Pakistan, and Bangladesh, respectively. A total of 71 sequential Orf1ab B-cell epitopes were predicted, and only three peptides were found to be antigenic, non-allergenic, and non-toxic. These epitopes were linked with the EAAAK linker to develop a 3D refined and validated structure. This construct was docked with TLR-3 receptor by the Cluspro webserver and found a high affinity of ORF1ab+TLR3 due to 15 hydrogen bonds. The construct demonstrated good humoral and cellular immune responses in the C-ImmSim server, and cloning in the expression vector pET28a (+) yielded a colon of 846bp.
Conclusions: ORF1ab B-cell epitopes could be useful for developing effective vaccines to combat SARS-CoV-2 infection.
Keywords: bioinformatics; epitopes; ORF1ab polyproteins; public health; Indonesia; SARS-CoV-2.

Resumen
Contexto: El virus SARS-CoV-2 es la causa de la pandemia de COVID-19, que es una grave crisis de salud pública a nivel mundial.Objetivos: Analizar los aislamientos de SARS-CoV-2 de Surabaya y predecir los epítopos de poliproteína ORF1ab mediante el enfoque bioinformático para el desarrollo de candidatos vacunales.
Métodos: Se obtuvieron tres secuencias genómicas de aislamientos de Surabaya de las bases de datos GISAID, NCBI and PDB Gen-bank y el software MEGA-11 para comprender las transformaciones en los aislamientos. Se utilizaron los servidores web IEDB y VaxiJen, AllerTop y ToxinPred para predecir epítopos de células B y analizar su antigenicidad, no alergenicidad y no toxicidad, respectivamente. Además, EAAAK vinculó estos epítopos para el modelado, el refinamiento y la validación en 3D a través de las herramientas web Swiss-Model, Galaxy Refine y RAMPAGE.
Resultados: Los aislamientos de Surabaya, RSDS-RCVTD-UNAIR-49-A, 54-A y 42-A, tenían 10, 20 y 16 mutaciones en nucleótidos y mostraban una relación filogenéticamente cercana con los aislamientos de Egipto, Pakistán y Bangladesh, respectivamente. Se predijeron un total de 71 epítopos de células B Orf1ab secuenciales, y solo tres péptidos resultaron ser antigénicos, no alergénicos y no tóxicos. Estos epítopos se vincularon con el enlazador EAAAK para desarrollar una estructura 3D refinada y validada. Esta construcción fue acoplada con el receptor TLR-3 por el servidor web Cluspro y encontró una alta afinidad de ORF1ab+TLR3 debido a 15 enlaces de hidrógeno. La construcción demostró buenas respuestas inmunitarias celulares y humorales en el servidor C-ImmSim, y la clonación en el vector de expresión pET28a (+) produjo un colon de 846 pb.
Conclusiones: Los epítopos de células B ORF1ab podrían ser útiles para desarrollar vacunas efectivas para combatir la infección por SARS-CoV-2.
Palabras Clave: bioinformática; epítopos; poliproteínas ORF1ab; Indonesia; salud pública; SARS-CoV-2.

Citation Format: Shehzad A, Kuncorojakti S, Tacharina MR, Ahmad HI, A'la R, Wijaya AY, Tyasningsih W, Rantam FA (2022) Molecular characterization and prediction of B-cell epitopes for the development of SARS-CoV-2 vaccine through bioinformatics approach. J Pharm Pharmacogn Res 10(3): 429–444. https://doi.org/10.56499/jppres21.1262_10.3.429
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