Personal service and the utmost care for our donors are the top priority at CTLS. Donor questions and feedback are always welcome as they enable us to continually improve our services. Clinical Trials Laboratory Services (CTLS) is a leading provider of human blood products and biological specimens to the research community. CTLS specializes in the collection of whole blood, serum, white cells, red cells and other biofluids from consented donors. Donors are screened according to AABB guidelines and undergo a complete battery of infectious disease state tests. For 26 years, specimens collected at CTLS have supported the development of therapeutics and in vitro diagnostic assays.