title: Source and route of exposure influence infectivity of a molecular clone of human T cell leukemia virus type I.
abstract: Infection with human T cell leukemia virus type I (HTLV-I) is typically asymptomatic, but does result in diverse diseases ranging from adult T cell leukemia to spastic neuromyelopathy. To date, differences in HTLV-I provirus structure have not been correlated with pathogenic or asymptomatic outcome of infection. Molecular clones of HTLV-I are now available and represent a powerful tool to link virus structure to pathogenesis. Present studies to explore in vivo infectivity and pathogenicity of an HTLV-I molecular clone, K30p, have utilized the rabbit as a model system. This clone was administered to neonatal or adult rabbits by several different routes and infectivity and pathogenicity were examined. Detection of antiviral humoral immune responses, presence of provirus in tissue samples, and isolation of virus in cultures of blood lymphocytes were used to establish systemic HTLV-I infection. Intramuscular, but not nervous system, exposure to K30p HTLV-I naked DNA resulted in infection. Conversely, neural exposure to T cells that had been transfected with the K30p HTLV-I DNA consistently resulted in systemic infection. Despite detection of HTLV-I provirus in brain and spinal cord of some infected rabbits, no clinical or neuropathological changes occurred. Source and route of virus exposure played a role in infectivity, but did not influence the pathogenic outcome of HTLV-I infection.
authors.affiliation: Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, Rockville, Maryland 20852, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Simpson
authors.forename: T M
authors.initials: TM
authors.lastname: Zhao
authors.forename: B
authors.initials: B
authors.lastname: Schmidt Hubbard
authors.forename: W
authors.initials: W
authors.lastname: Said
authors.forename: T J
authors.initials: TJ
authors.lastname: Kindt
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004279:DNA, Viral / Q000032:analysis; D015480:Deltaretrovirus Antibodies / Q000097:blood; D006800:Deltaretrovirus Infections / Q000821:virology*; D015683:Gene Products, gag / Q000097:blood; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D008214:Lymphocytes / Q000821:virology; D009132:Muscles; D009420:Nervous System / Q000821:virology; D011533:Proviruses / Q000302:isolation & purification; D011817:Rabbits; D015682:Retroviridae Proteins, Oncogenic / Q000097:blood; D013601:T-Lymphocytes / Q000821:virology; D014774:Virulence; D054301:gag Gene Products, Human Immunodeficiency Virus
chemical_list: D004279:DNA, Viral; D015480:Deltaretrovirus Antibodies; D015683:Gene Products, gag; D015682:Retroviridae Proteins, Oncogenic; D054301:gag Gene Products, Human Immunodeficiency Virus; C060955:p19 protein, Human T-lymphotropic virus 1