Genome-wide Transcriptional Responses of Leptospira interrogans to Host Innate Immunity (CBX129). unidentified

To study global transcriptional responses of L. interrogans upon interaction with the host innate immune system, we chose two different mammalian cell lines: murine monocyte-macrophage-like cell line J744A.1 and human acute monocytic leukemia cell line THP-1, which represent interaction with macrophage of either natural mammalian reservoir or human host (lethal infection), respectively. Briefly, a clonal strain of L. interrogans Serovar Lai Strain Lai 56601 was first subjected to infect a guinea pig and recovered from the kidney. Isolated infectious spirochetes were then split to two samples. One sample was kept under in vitro cultivation and passage in EMJH medium for five generations (approximately two months). This sample was then subjected to RNA extraction and defined as in vitro cultivation sample (sample E0). The other sample was further divided to three samples and co-cultured with cell lines J744A.1, THP-1, or the mammalian cell culture medium (RMPI 1640) alone. These samples were designated as sample J, T, or M, respectively. After 45 or 90 minutes, spirochetes were harvested and then subjected to RNA extraction and cDNA synthesis.