Mathematical Model of a Virus-neutralizing Immunglobulin Response

✍ Scribed by G.A. Funk; A.D. Barbour; H. Hengartner; U. Kalinke

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 234 KB
• Volume: 195
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.1998.0779

✦ Synopsis

We present a mathematical model to simulate the kinetics of B-cell activation and the virus-neutralizing immunoglobulin response in the spleen of mice after infection with vesicular stomatitis virus (VSV). Our model combines data from in vitro experiments and in vivo kinetic observations. A system of eight nonlinear differential equations was used in the computer experiments and numerically solved. The isotype switch from IgM to IgG in the presence of T-cell help was modelled by a time variable function, used as a parameter.

The model solutions indicate fast kinetics of the generation of VSV-neutralizing IgM antibodies within 2-3 days post immunization peaking on day 5 at a serum concentration of 080 mg ml -1 IgM, which is equivalent to about 10% of the total IgM serum concentration. The frequency of virus-specific B cells increases about 1000-fold within the first 4 days after immunization. Protective levels of VSV-neutralizing IgG antibodies (e10 mg ml -1 ) are reached within 5 to 6 days post immunization. Fitting the model solutions to the experimentally observed neutralizing serum titers suggests an increase in the neutralizing activity of IgGs occuring between days 5 and 8 post-infection. The model indicates that less than 10 VSV-specific B cells have to be triggered daily to maintain protective IgG serum titers during the memory phase.