As far as I can understand this shows the events by which a white blood cell 'walks' along the wall of a blood vessel, spots an infection, and then squeezes itself out of the blood vessel to attack the infection. It's extraordinarily complex. Here is a much simpler animation (about half a minute) showing the same process as it looks from outside the cell.
The bit that impressed me most was a vesicle carrying a big sack of information protein 'walking' along a track towards the cell surface. It's like a motorway in an alien city. It is remarkable that we are so complex at all levels simultaneously. No wonder it took three billion years for monocellular life to develop.
Interestingly I was reading a book yesterday called 'Rituals of Healing' which is about using mental imagery to stimulate or otherwise regulate the immune system. This is written by some nurses and it was American Journal of Nursing book of the year, so it is rooted in clinical practice. This is approaching exactly the same physical process, from the other end.
We can't will the walking vesicles to walk a bit faster, or the rheticuloproteins to squeeze through the membranes more efficiently. But somehow by altering our mental visualisation of our bodies we can harm or help the process. I think an understanding of the complexity helps me to accept that the controls are very high level, and then you have to trust the body to interpret those control signals at all fractal levels.