Protected, in a way (6)
'protected in a way' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for immune that I've seen before include "Secure against, infection say" , "Exempt from obligation" , "Safe from attack" , "Safe from infection etc" , "Resistant (to infection)" .)
(Other definitions for padded that I've seen before include "Walked on foot; stuffed" , "Kind of cell for violent prisoners" , "Covered with anything soft; stuffed" , "Cushioned; moved silently" , "Filled with wadding" .)