Illinois State Universities Retirement System, Champaign, and Illinois Teachers' Retirement System, Springfield, will be among Illinois public funds sending top officials to an Aug. 17 meeting in Chicago, called by Northern Trust to discuss the company's staff departures and other issues. Northern Trust issued a statement saying the meeting will focus on "our global investment strategy, recent staffing changes, our commitment to Illinois, the community, and the public fund marketplace — an important and valued market segment for Northern Trust." Richard Jurek, vice president-corporate communications, said Northern Trust officials would not comment further and could not say whether a meeting had been set up with corporate pension plan clients. "We are concerned with respect to the management of that money and Northern's ability to staff that area," said James M. Hacking, Illinois SURS executive director. The $12.6 billion system, which has $2.6 billion in a Wilshire 5000 index fund run by Northern Trust Global Investments, has not put the firm on watch. The $31 billion lllinois Teachers system put NTGI, which runs $1.6 billion in passive equity and fixed income for the system, on watch for organizational changes.