Te-Yao Hsu and Chia-Yo Ou contributed equally to this article.
l-Arginine modulates neonatal lymphocyte proliferation through an interleukin-2 independent pathway
Version of Record online: 8 SEP 2014
© 2014 John Wiley & Sons Ltd
Volume 143, Issue 2, pages 184–192, October 2014
How to Cite
Yu, H.-R., Kuo, H.-C., Huang, L.-T., Chen, C.-C., Tain, Y.-L., Sheen, J.-M., Tiao, M.-M., Huang, H.-C., Yang, K. D., Ou, C.-Y. and Hsu, T.-Y. (2014), l-Arginine modulates neonatal lymphocyte proliferation through an interleukin-2 independent pathway. Immunology, 143: 184–192. doi: 10.1111/imm.12300
- Issue online: 8 SEP 2014
- Version of Record online: 8 SEP 2014
- Accepted manuscript online: 3 APR 2014 06:59AM EST
- Manuscript Accepted: 1 APR 2014
- Manuscript Revised: 23 MAR 2014
- Manuscript Received: 27 DEC 2013
- National Science Council. Grant Numbers: CMRPG8B0781, 102-2314-B-182A-042-MY3
- lymphocyte proliferation;
In cases of arginine depletion, lymphocyte proliferation, cytokine production and CD3ζ chain expression are all diminished. In addition to myeloid suppressor cells, polymorphonuclear cells (PMN) also exert T-cell immune suppressive effects through arginase-induced l-arginine depletion, especially during pregnancy. In this study, we investigated how arginase/l-arginine modulates neonatal lymphocyte proliferation. Results showed that the neonatal plasma l-arginine level was lower than in adults (48·1 ± 11·3 versus 86·5 ± 14·6 μm; P = 0·003). Neonatal PMN had a greater abundance of arginase I protein than adult PMN. Both transcriptional regulation and post-transcriptional regulation were responsible for the higher arginase I expression of neonatal PMN. Exogenous l-arginine enhanced neonate lymphocyte proliferation but not that of adult cells. The RNA-binding protein HuR was important but was not the only modulation factor in l-arginine-regulated neonatal T-cell proliferation. l-Arginine-mediated neonatal lymphocyte proliferation could not be blocked by interleukin-2 receptor blocking antibodies. These results suggest that the altered arginase/l-arginine cascade may be one of the mechanisms that contribute to altered neonatal immune responses. Exogenous l-arginine could enhance neonate lymphocyte proliferation through an interleukin-2-independent pathway.