Vδ2 T‐lymphocyte responses in cord blood samples from Italy and Côte d’Ivoire

Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Immunology (Impact Factor: 3.8). 08/2008; 124(3):380-7. DOI: 10.1111/j.1365-2567.2007.02784.x
Source: PubMed


Cord blood T lymphocytes are immature and their functional defect partially reflects a suboptimal level of costimulatory signals provided by neonatal antigen-presenting cells. Neonatal Vdelta2 T lymphocytes, a small component of cellular immunity involved in the response against bacteria, protozoa, virus-infected cells and tumours, are also considered to be immature. Cord blood Vdelta2 T lymphocytes are mostly naïve, proliferate poorly and do not produce cytokines in response to the model phosphoantigen isopentenyl pyrophosphate. We cultured cord blood mononuclear cells with the aminobisphosphonate Pamidronate or with live bacille Calmette-Guérin, and showed that both elicit a strong cord blood Vdelta2 T-cell proliferative response, inducing the expression of activation markers and promoting the differentiation from naïve to memory cells. Our results suggest that cord blood Vdelta2 T cells are not inherently unresponsive and can mount strong responses to aminobisphosphonates and mycobacteria. Neonatal Vdelta2 T lymphocytes may be important participants in responses to microbial infections early in life.

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Available from: Giulia Cappelli, Oct 27, 2014
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    • "Immune response mechanisms in neonates, especially in preterms, are not well established and they are considered very premature and insufficient to fight infections (Marodi 2006; Schelonka and Infante 1998). However, even during the fetal period immune response to mother’s infection is observed (Zhao et al. 2002), and cord blood mononuclear cells are known to secrete significant amounts of proinflammatory cytokines (Cairo et al. 2008; Chipeta et al. 2000; Koehler et al. 2008). Yet the development of the human immune system during the prenatal and perinatal period is not precisely understood. "
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