The genetic profiling of preferentially expressed genes in murine splenic CD8α+ dendritic cells.

In the murine splenocytes, CD8α+ dendritic cells (abbreviated as 8+DC) and CD8α- dendritic cells (abbreviated as 8-DC) are identified with some vague features for each of them. 8+DCs but not 8-DCs cross-prime cytotoxic T cells in vivo. We aim to distinguish the two subtypes of DC based on gene expression profiling. Suppressive subtractive hybridization was undertaken to get differentially expressed genes from such subtracted cDNA library specific to 8+DC. A total of 114 sequences from the subtracted cDNA library specific to 8+DC library were analyzed. Most of them are known proteins, but some of them were novel, either totally novel genes or homologs to known genes, but with novel exon. About 55 probably novel exons were discovered, and 11 exons had longer length than those in gene bank. The clones 12, 44, 79, and 110 have no match with known sequences in gene bank. Then, semi-quantitative PCR was done to compare the expression of the enriched sequences between 8+DC and 8-DC. About 14 genes are differentially expressed in 8+DC. Therefore, SSH is an effective method to clone differentially expressed genes for 8+DC compared to 8-DC.