title: Exposure of human CD34+ cells to human immunodeficiency virus type 1 does not influence their expansion and proliferation of hematopoietic progenitors in vitro.
abstract: The susceptibility of highly purified human CD34+ cells to monocytotropic (Ba-L) and lymphotropic (A018-post) strains of human immunodeficiency virus-1 (HIV-1) was examined. Liquid cultures initiated with fresh immunomagnetically purified CD34+ cells using the K6.1 CD34 monoclonal antibody (MoAb) (K6.1/CD34+) were positive for HIV expression 2 weeks after exposure to HIV-1 Ba-L. These cells were initially greater than 90% CD34+ and had undetectable monocyte contamination by flow-cytometric staining and side-scatter analyses, respectively, and undetectable T-cell contamination by CD3 polymerase chain reaction (PCR) analysis. However, secondary CD34+ liquid cultures reselected from the primary liquid cultures 24 hours after HIV exposure by panning with the ICH3 CD34 MoAb (ICH3/CD34+) and maintained for an additional 14 days were negative for HIV expression. The ICH3-unbound cells were positive for both spliced and unspliced HIV RNA when exposed to HIV-1 Ba-L, and were DNA PCR positive when exposed to either monocytotropic or lymphotropic HIV-1. To further test that CD34+ cells were not infectible by HIV-1, we exposed K6.1/CD34+ cells continuously to HIV-1 in a culture system capable of maintaining and expanding primitive CD34+ cells. HIV-exposed K6.1/CD34+ cells proliferated and expanded as efficiently as uninfected cultures. However, when reselected magnetically using the K6.1 CD34 MoAb after expansion for 7 days, bound K6.1/CD34+ cells were again negative for HIV-1 expression, whereas unbound cells were positive for HIV-1 expression. These findings suggest that a sequential CD34+ cell-selection process, in which the two selections are separated by a brief culture period, can yield a population of CD34+ cells that are not infected with HIV-1. This process may be useful in the design of stem or progenitor cell-based transplantation therapies for HIV infection.
authors.affiliation: Department of Hematology and Vascular Biology, Walter Reed Army Institute of Research, Washington, DC; USA.
authors.forename: S
authors.initials: S
authors.lastname: Kaushal
authors.forename: V F
authors.initials: VF
authors.lastname: La Russa
authors.forename: S
authors.initials: S
authors.lastname: Gartner
authors.forename: S
authors.initials: S
authors.lastname: Kessler
authors.forename: S
authors.initials: S
authors.lastname: Perfetto
authors.forename: Z
authors.initials: Z
authors.lastname: Yu
authors.forename: D W
authors.initials: DW
authors.lastname: Ritchey
authors.forename: J
authors.initials: J
authors.lastname: Xu
authors.forename: P
authors.initials: P
authors.lastname: Perera
authors.forename: J
authors.initials: J
authors.lastname: Kim
authors.forename: T
authors.initials: T
authors.lastname: Reid
authors.forename: D L
authors.initials: DL
authors.lastname: Mayers
authors.forename: D
authors.initials: D
authors.lastname: St Louis
authors.forename: J D
authors.initials: JD
authors.lastname: Mosca
mesh_terms: D018952:Antigens, CD34 / Q000032:analysis*; D001483:Base Sequence; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D005434:Flow Cytometry; D015497:HIV-1 / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000821:virology*; D006801:Humans; D018189:Immunomagnetic Separation; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D014779:Virus Replication
chemical_list: D018952:Antigens, CD34