Delvelopment of ELISA for Determining Antimumps IgG and Its Comparison with Virus Neutralization Test

Mumps virus is the cause of a contagious disease mostly seen in children and young adults.Immunoglobulin G protects individuals from reinfection. Because of the broad range of incubation time in various individuals, the presence of the virus in saliva before the appearance of clinical symptoms and infection of many individuals without symptoms makes the control of the transmission of the disease difficult. Therefore, vaccination is the best way to control the disease and spread of the viral agent. In addition, laboratory methods with a high sensitivity are needed to determine vaccine efficiency and to identify susceptible groups and infected individuals.

In this research, we used the viral neutralization test (VNT) and ELISA to determine IgG titers. First, the VNT was performed for 400 cord blood samples from which, 91.7% were detected to be positive. A vero cell line was infected with Hushino strain of mumps virus. By the hemadsorption test, the virus propagation in the infected cell line was confirmed. Later, the cultured virus was concentrated by PEG 6000, then purified by sucrose gradient and the amount of the protein was determined. The purified virus was coated on the micotiter plates and an indirect ELISA was performed. We used the VNT as a golden standard to determine the efficiency of our designed ELISA method.

The results demonstrated that the two methods have a good correlation. The sensitivity and specificity of our ELISA system was 100% and 97% respectively. Thus, our ELISA technique is a reliable method to determine mumps virus antibody titer.