  We study the solutions of the two-dimensional Keller-Segel system describing
chemotaxis. The Keller-Segel system as well as the properties of the blow-up
set has been extensively studied. In this paper we obtain generalized solutions
for the Keller-Segel system in the sense of measures as the limit of
two-different regularizations of it. We will show that the resulting limit
measures, that are in some suitable sense global weak solutions of the
Keller-Segel system, depend in the regularization.
