Dendritic cells (DC) are potent primary antigen presenting cells (APC). Previously we demonstrated that GM-CSF enhances proliferation in an allogeneic MLR of rat pulmonary DC and resting T cells. Since B7 molecules expressed on APC contribute to their capacity to stimulate T cells, we are studying regulation of their expression in pulmonary DC. We cloned and sequenced a partial cDNA of the previously unreported rat B7-2 gene and used semi-quantitative RT-PCR (reverse transcriptase-polymerase chain reaction) to measure changes in mRNA expression of B7-1 and B7-2. Primers for PCR amplification of the rat gene were designed from mouse and human sequences. These were used to amplify cDN A products synthesized from RN A of cultured rat lung DC. The longest clone (449bp) sequenced (GenBank ace. RNU31330) corresponds to 50% of the coding region of mouse B7-2. It shares 89% identity with the mouse nucleic acid sequence and 83% with the coded amino acid sequence. Pulmonary DC (>90% pure; low density, non-phagocytic, MHC class II bright) were cultured in the presence or absence of recombinant mGM-CSF, rGM-CSF, mM- CSF, mTNFa, mIL-1/3 or mIFN7. RNA was isolated and amplified by RT-PCR. Analytical PCR primers and probes were designed from rat B7-1, B7-2, /Jactin and GAPDH sequences. Products were analyzed from hybridized Southern blots. Expression of both B7-1 and B7-2 was enhanced by GM- CSF, TNFα or IL-1β, but not by M-CSF or IFNγ.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology