Pension fund invests in Blackstone infrastructure fund and Principal separate account. : Teachers’ Retirement System of the State of Illinois (TRS Illinois) is investing $600m (€517m) in real estate and infrastructure strategies. The pension fund said in a meeting document that it has approved $300m into Blackstone Infrastructure Partners, $100m into Principal Real Estate Investors and $200m with into The Fortress Group. TRS Illinois joins Teacher Retirement System of Texas, Pennsylvania Public School Employees Retirement System and New Mexico State Investment Council, all of which have backed the Blackstone fund.