Welcome to FT and the *A forum,
dellawac!
Your questions is normally better placed in the US forum.
There is something called the Star Alliance Upgrade program where members of Frequent Flyer Program can use miles to upgrade on other *A carriers.
However, not every carrier in Star Alliance participates. AFAIK US is not part of the program so you can not use US Air miles to upgrade LH flights or not use other programs miles to upgrade on US.
Here is a link to the United site which lists participating carriers:
http://www.united.com/page/article/0,6867,52927,00.html