No they don't, sometimes the Eldar work with humans to help their goals and then they don't particually won't to. In their tongue they still call humans 'monkeys' Uriel Ventris of Ulthe once had an age old pack with the Deathwatch to aid him in any way, but he never really used it and now hes pretty much dead now after the eye of terror campaign. The lore says he may come back because he left parts of his soul in soulstones, but time will tell.