# Assessment of Biological Properties of Recombinant Lumpy Skin Disease Viruses with Deletions of Immunomodulatory Genes

## TL;DR

Scientists tested how deleting specific genes in a virus affects its replication and immune response in mice, aiming to improve vaccine design.

## Contribution

The study demonstrates that deleting certain immunomodulatory genes in Lumpy Skin Disease Virus can enhance vaccine effectiveness without impairing replication.

## Key findings

- Deleting LSDV005 or LSDV008 genes did not reduce virus replication in cell cultures.
- Deleting LSDV066 or combining it with LSDV005/LSDV008 reduced virus replication.
- Knockout of LSDV005 gene in recombinant virus induced antibody production to a foreign antigen in mice.

## Abstract

Rational design of capripoxvirus-based vaccine vectors can be achieved by knockout of immunomodulatory genes. In this study, the effect of knockout of the immunomodulatory genes LSDV005, LSDV008 and LSDV066 on the replication of Lumpy skin disease virus in cell cultures and the immune response to an integrated foreign antigen were assessed. The knockout of genes was performed by homologous recombination under conditions of temporary dominant selection. It was found that single knockout of the LSDV005 gene and the LSDV008 gene did not affect the replicative activity of recombinant viruses in vitro (Atyrau-5 and Atyrau-B). Both single knockout of the LSDV066 gene and in combination with knockout of LSDV005 or LSDV008 led to a decrease in the replicative activity of recombinant LSDVs. The recombinant Atyrau-5J(IL18) with LSDV005 gene knockout induced production of antibodies to the integrated antigen in mice. Prime-boost vaccination with all studied recombinants increased the level of interferon-γ. In addition, during immunization with the recombinant Atyrau-5J(IL18) secretion of interleukin-2 was significantly increased. The study of the functions of immunomodulatory genes and their effect on the expression of inserted sequences of foreign antigens is promising for the creation of highly effective polyvalent vector vaccines for animals.