でして is the continuous usage of です, thus, it suggests that the sentence still continues, and the following part is omitted, for instance, うちは気象庁とも連携した極めてまっとうな研究室でして、ほんとはあまり乗り気じゃないんですよ. (I don't know the context, so the omitted part is just my impression.)
The context is the protagonist, who works for an editorial office of an otaku magazine, comes to the research institute to have an interview with the researcher, so that he can get some materials for the article.
So does this でして indicate reason or cause? Is it similar to ので? If so, how is it different from ので?