Effects of infection of EGFP-expressing Escherichia coli on haemocytes in Ciona intestinalis

• Published in: Journal of experimental marine biology and ecology Vol. 332; no. 2; pp. 121 - 134
• Main Authors: Liu, Liping, Wu, Changgong, Chen, Taoying, Zhang, Xiaojun, Li, Fuhua, Luo, Wen, Xiang, Jianhai
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2006; Elsevier Science
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Apoptosis; Biological and medical sciences; Cellular response; Ciona intestinalis; EGFP-expressing E. coli; Escherichia coli; Fundamental and applied biological sciences. Psychology; Haemocytes; Infection; Marine; Sea water ecosystems; Synecology; Infection; TUNEL; Ciona intestinalis; EGFP-expressing E. coli; Haemocytes; SCGE; EGFP; THC; Apoptosis; Cellular response; Escherichia coli; Prochordata; Urochordata; Marine environment; Aquatic environment; Bacteria; Invertebrata; Enterobacteriaceae
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/j.jembe.2005.11.022

The effects of infection of EGFP-expressing Escherichia coli on the haemocytes of the ascidian Ciona intestinalis were investigated. The results showed that THC of the infected individuals changed significantly. Hyaline amoebocytes phagocytosed E. coli in 5 min and excreted lysosome particles that attached to the surface of the bacteria. Granular amoebocytes released lots of particles for humoral immunity while stem-cell-like haemocytes remained intact. With the increase in THC, the stem-cell-like haemocytes showed division and proliferation. A small portion of hyaline amoebocytes was at early apoptosis stage 1 h after infection and typical apoptosis bodies emerged in granular amoebocytes. A few of the infected haemocytes showed DNA damage using SCGE assay. Flow cytometry analysis revealed an obvious apoptosis peak in infected haemocytes. In conclusion, apoptosis was found to be an important immune response of ascidian haemocytes response to bacterial infection. To our best knowledge, this is the first report of the occurrence of apoptosis of haemocytes in ascidians.