Molecular detection and characterization of foot mouth disease virus FMDV and study of cytikine expression in naturally infected local crossbred cattle from Assam

Abstract

Foot and mouth disease (FMD) is a transboundary and the most contagious newlinedisease of cloven-hoofed animals including domestic and wild ruminants and pig, and newlinehas a great potential for causing severe economic loss due to loss of production and newlinedeprivation from international trade of animal products to FMD free countries. FMDV newlinemay occur in all the secretions and excretions of acutely infected animals, including newlineexpired air. Following recovery from the acute stage of infection, infectious virus may newlinepersist in the oropharynx of some ruminants (carriers), where live virus or viral RNA newlinemay continue to be recovered from oropharyngeal fluids and cells for upto 6 months or newlinemore. In this study, besides Sandwich ELISA, molecular detection and typing of FMDV newlinewas done using multiplex Reverse Transcription Polymerase Chain Reaction (mRTPCR), newlineReverse Transcription Loopmediated Isothermal Amplification (RT-LAMP) and newlineSYBR Green real-time PCR targeting 3D gene. Isolation and molecular characterization newlineof FMDV by sequencing was done. Also, study of expression of cytokines like interferon newline(IFN-and#945;, IFN-and#946;, IFN-and#61543;) as well as certain interleukins (IL-1and#945;, IL-1and#946;, IL-2, IL-6, IL-10 and newlineIL-12) and tumour necrosis factor (TNF-and#945;) was estimated at mRNA level by SYBR newlineGreen real-time PCR from whole blood (White Blood cells) samples during the natural newlineinfection and during the period of persistence. newlineThis study was carried out in a total of 129 animals, comprising of 93 crossbred newline(vaccinated) and 36 local (non-vaccinated) cattle and additionally 12 healthy in-contact newlineanimals were taken as control animals. For carrying out this study, Tissue (n=29), whole newlineblood (n=36) and oropharyngeal fluid (n=190) samples were collected as per standard newlineprocedure in 50% glycerol, EDTA and 0.8 M PBS/transport media, respectively. OP newlinefluid was collected from recovered animals until complete recovery (i.e. 1st, 3rd, 6thand newline9thmonth) from FMD infection. All the RNA extractions were done using Qiagen RNA newlineextraction kit. newlineWe found that, out of 29 tissue samples, 20 samples w