Kneading dough with long nails; latex gloves?
Long nails will puncture smooth thin latex gloves (the surgical type) very quickly, especially during something like kneading where the gloves slide against your fingers all the time. Thick latex gloves, like the one for washing dishes, will be more durable, but they are also grippy and a lot of dough will stick. Also, they are usually not food safe. 

If you really need something, I guess clear wide plastic gloves, like the ones in hair colorant packs, will work better, but I don't know where you can get them as explicitly food safe. 

Personally, I would just knead barehanded. The underside of long nails can be washed just as easily as the upper side, and nobody finds it unhygienic to have the upper side of nails (short or long) touch dough. The real problem would come if you keep short nails and cannot remove the dirt which sticks between the nailtip and the meat of the finger. Long nails are much easier in that regard.