John Johnson, PhD Research Interests
My area of interest is to
understand the underlying molecular mechanisms by which viruses overcome
complement pathways. The human complement system a part of the innate immune
system which consists of a group of intricate and concerted group of proteins
is a potent first line of defense against a range of pathogens including
viruses. We have focused on interactions of complement with Paramyxoviruses, a
medically-important group of non-segmented, enveloped, negative strand RNA
viruses of both clinical and veterinary significance.
The complement system is
rightfully considered a ‘double-edged sword’, meaning, besides acting on
pathogens, it can target the host. However this is thwarted by a group of
proteins called as regulators of complement activation, which include CD46,
CD55, factor H etc. We have shown that PIV5 and Mumps virus, two closely
related paramyxoviruses, hijack CD46 and CD55 from the host cells during the
process of virus budding and egress and use it to inactivate complement
proteins thus evading neutralization. Currently my focus is on understanding
the process of regulatory protein recruitment by these viruses. Of key interest
is to identify the specificity of this process and which viral proteins
contribute to this recruitment. Also another area of pursuit is unlocking the
regulation both at the transcriptional and translational level within the host
which is mediated by these viruses both in vitro and in vivo. Unraveling the
molecular mechanisms of complement-paramyxovirus interaction is critical in
developing both efficient and safer vaccines, as well as more potent oncolytic
vectors