Date of Award


Document Type

Doctoral Thesis

Degree Name

Doctor of Philosophy


Department of Biological Sciences

First Advisor

Dr. Helen O'Shea


The subject of viral entry into, and subsequent progeny virus egress, from cultured cells, has been extensively studied using numerous scientific techniques in fields ranging from cell culture to biochemistry to microscopy. The atomic force microscope (AFM) is a novel, developing instrument with unprecedented capabilities and this study was undertaken to observe enveloped Semliki Forest virus (SFV) and non-enveloped Theiler's Murine Encephalomyelitis virus (TMEV) entry into and egress from cultured cells using the AFM. Virus particle structure of both enveloped and non-enveloped viruses was also directly examined.

Cytopathic effect studies revealed that TMEV's are unable to produce progeny viruses in AT3Neo cells. AFM analysis of TMEV entry into AT3Neo cells revealed that the viruses are capable of infecting AT3Neo cells. These results indicate a post-entry block in the TMEV replication cycle in AT3Neo cells. AFM analysis of the egress of progeny viruses from cultured cells demonstrated that virally induced cytopathic effects can be visualised with the AFM. No consistent effects on cell viscoelasticity were observed during viral entry into and progeny virus egress from cultured cells. AFM analysis of virus particles demonstrated that antibody-coated (anti-capsid antibody and anti-envelope antibody) wafers are an effective means for the immobilisation of both enveloped and non-enveloped virus particles. Virus particles were successfully imaged and in all cases the virus particles appeared to collapse when they were immobilised.

Access Level


Included in

Virology Commons