The main objective of this contract project is to provide clinical grade retrovirus vector supernatant that will be used for targeting somatic human cells ex vivo in trials of gene therapy. This will involve the production of a master cell banks of the retrovirus producer lines, cryopreservation storage of such banks, in some cases production of working cell banks and cryopreservation storage of such banks, production of multi-liter quantities of clinical grade retrovirus supernatant and its storage by cryopreservation. An integral part of this objective is performance of a variety of safety testing on the cell lines which produce the retrovirus vector supernatant, the retrovirus supernatant itself, and on the human cells that are transduced with this retrovirus vector in culture. Such safety testing would include, but is not restricted to verification of the source of producer lines, detection of many types of contaminating pathogenic organisms, and detection of replication competent retrovirus. Such safety testing will be performed in a manner which will verify that the retrovirus supernatant and transduced cell products to be used in the clinical trial conform to the safety standards set by regulatory requirements of the United States Food and Drug Administration. One of the target diseases for such gene therapy trials is the inherited immune system deficiency known as chronic granulomatous disease (CGD). In the clinical trial for CGD the blood stem cells derived from patients with CGD will be exposed in culture to the clinical grade retrovirus provided by this contract. The actual culture and transduction of stem cells is not part of this contract project, but the safety testing of the transduced stem cell product is an objective of the contract project.