This is a Phase I, single institution, open-label, within-dosing-cohort-schedule randomized, dose escalation study of TXA127 in HIV-infected subjects with CD4+ T-lymphocyte counts less than 250 per mm3 who have responded to highly active retroviral therapy (HAART). The study has been designed to determine the maximum tolerated dose (MTD) of TXA127 in this subject population. This study will also obtain safety and biologic activity information about the subcutaneous injection of TXA127.