tailieunhanh - Báo cáo y học: " Population dynamics of an RNA virus and its defective interfering particles in passage cultures"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Population dynamics of an RNA virus and its defective interfering particles in passage cultures | Thompson and Yin Virology Journal 2010 7 257 http content 7 1 257 VIROLOGY JOURNAL RESEARCH Open Access Population dynamics of an RNA virus and its defective interfering particles in passage cultures Kristen A Stauffer Thompson John Yin Abstract Background Viruses can fall prey to their defective interfering DI particles. When viruses are cultured by serial passage on susceptible host cells the presence of virus-like DI particles can cause virus populations to rise and fall reflecting predator-prey interactions between DI and virus particles. The levels of virus and DI particles in each population passage can be determined experimentally by plaque and yield-reduction assays respectively. Results To better understand DI and virus particle interactions we measured vesicular stomatitis virus and DI particle production during serial-passage culture on BHK cells. When the multiplicity of infection MOI or ratio of infectious virus particles to cells was fixed virus yields followed a pattern of progressive decline with higher MOI driving earlier and faster drops in virus level. These patterns of virus decline were consistent with predictions from a mathematical model based on single-passage behavior of cells co-infected with virus and DI particles. By contrast the production of virus during fixed-volume passages exhibited irregular fluctuations that could not be described by either the steady-state or regular oscillatory dynamics of the model. However these irregularities were to a significant degree reproduced when measured host-cell levels were incorporated into the model revealing a high sensitivity of virus and DI particle populations to fluctuations in available cell resources. Conclusions This study shows how the development of mathematical models when guided by quantitative experiments can provide new insight into the dynamic behavior of virus populations. Background Defective interfering DI particles are virus-like byproducts of infections that .