H. M. Bligh Cancer Research Laboratories, Department of Microbiology and Immunology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL.
KSHV entry into human dermal microvascular endothelial cells (HMVEC-d), a natural in vivo target cell, via macropinocytosis is initiated through a multistep process involving binding of KSHV envelope glycoproteins with cell surface α3β1, αVβ3 and αVβ5 integrin molecules and tyrosine kinase EphrinA2 receptor followed by the activation of integrin-associated pre-existing signaling molecules such as FAK, Src, c-Cbl, PI3-K and Rho-GTPases. Many viruses, including KSHV, utilize cellular reactive oxygen species (ROS) for viral genomic replication and survival within host cells; however, the role of ROS on early events of viral entry and induction of signaling has not been elucidated. Here we show that KSHV induced ROS production very early during infection of HMVEC-d cells which was sustained over the observed 24 h post-infection. ROS induction was dependent on KSHV binding to the target cells since pretreatment of virus with heparin abolished ROS induction. Pretreatment of HMVEC-d cells with the antioxidant N-Acetyl-Cysteine (NAC) significantly inhibited KSHV entry and consequently gene expression without affecting virus binding. In contrast, H(2)O(2) treatment increased KSHV entry and infection. In addition, NAC inhibited KSHV infection induced translocation of αVβ3 integrin into lipid rafts, actin dependent membrane perturbations such as blebs observed during macropinocytosis and activation of EphrinA2 receptor, FAK, Src and Rac1 signal molecules. In contrast, H(2)O(2) treatment increased the activation of EphrinA2, FAK, Src and Rac1. These studies demonstrate that KSHV infection induces ROS very early during infection to amplify the signaling pathways necessary for its efficient entry via macropinocytosis in HMVEC-d cells.
Am old enough to understand the difference between the Bay of Pigs - and roasting a pig at a epicurian feast. Been thru the hippy, yippie and yuppie years - always remaining who I am.
Very much believe in "Sing your own song - weave your own tapestry"
Am young enough to still know the thrill of new discoveries, the beauty of the evening, to celebrate the joy of another tommorow.
Survived these many decades with a severe medical problems. Sorting out the maze of now having two lymphomas and all their nasty little companions, but I continue.
Besides, being a simple iconoclastic eclectic, have been called many things. An incurable romanticist - with a strong touch of reality. Thinker, intellectual (God, how I hate that term) - been told I am a lion with the heart of the poet.
Know how to wage war and conquer my foes - but would rather be known as one who brings hope and life. To bring hope into anothers life is the ultimate of joys.
Life should be about bringing hope, peace, vision... a sense of purpose beyond yourself.