Peripheral blood dendritic cells(PBDC) are potent antigen presenting cells(APC) and believed to play an important role in AIDS progression. DC are highly susceptible to HIV-1 infection, and produce over 50 times more progeny virus than HIV-1
infected
primary CD4+ T cells, suggesting that some DC-specific cellular factors may be involved in the higher susceptibility of DC to HIV-1. Primary T cells, B cells, monocytes and DC were purified from the PBL through sequential cell isolation
procedures.
cDNAs were synthesized from the purified cells respectively, and were used as target DNAs for quantitative PCR and random amplified polymorphic DNA(RAPD) experiments. The relative amounts of mRNA expression for NF-kB50, NF-kB65, SP-1, TFIIDa, and
USF in
each cell type were investigated with each pair of PCR primers. In this experiment, we could not find any differences in the amounts of expression for those HIV-1-related cellular transcription factors between T-cells and DC, suggesting that some
other
cellular factors might exist for the higher sensitivity of DC to HIV-1 infection, Thirtytwo DC-specific PCR framents were identified through the RAPD experiment. cDNA fragments were sequenced and applied for the homology search to the GenBank
database.
Among the 32 clones, five of them showed no homology to any GenBank database, 4 showed weak homology with several reported clones, and 3 showed perfect match t HLA-related DM molecules whose specificity to DC was perviously reported (Bae et. al.
Mol
Cells 5: 569-578,1995). One of the clone, 652-b, were sequenced further to identify its open reading frame. A plausible single open reading frame is deduced, but still shows no homology to any functional proteins in its amino acid sequence even
in
a
small portion. These clones are remained to study further for their characteristics in association with HIV-1 replication in DC.
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