FIG 5.

BoHV-1 infection increases the number and length of TNT connections. KOP cells and bovine fibroblasts were grown for 1 day on gelatin-coated coverslips and infected with BoHV-1-WT at an MOI of 1. Control cells were left uninfected. At 18 h.p.i., cells were fixed and stained with Alexa Fluor 488-phalloidin conjugate to visualize the actin cytoskeleton. The number and length of cell connections were quantified using confocal microscopy. TNT connections between infected and uninfected cells were manually counted and measured in 6 separate experiments. Data were collected using the Lucia program. (A) Comparison of the frequency of nanotubes formation in BoHV-1-infected and in uninfected cells. (B) Comparison of TNT length. (C) Analysis of ratio of short (≤20 μm) to long (>20 μm) TNTs showed a significant shift toward long connections upon BoHV-1 infection. Data collected in 6 separate experiments represent the means, normalized to the value for control (uninfected) cells, arbitrarily set at 100%. *, P < 0.01.