Asymmetric T Lymphocyte Division in the initiation of Adaptive Immune Responses

Speaker: Yi Wang                                                                    Place: 601

Commentator: Yee-Shin Lin                                                   Time: 3:10-4:10 pm

Abstract:

A feature of mammalian immunity is heterogeneity of cell fate existing among lymphocytes activated by pathogen. In their experiment, the authors discovered that during first division of naïve T cells, asymmetric segregation of signaling, adhesion and polarity proteins dependent on prolonged contact between T cells and dendritic cells (DCs) contributed to asymmetric cell division. They hypothesized that unequal inheritance of determinants of cell fate leaded to effector or memory T cell lineage development in the first two daughter cells. They analyzed polarity of immune receptors, adhesive molecules, and signaling proteins in the first two daughter cells. They found that one of them expressed more effector markers and the other expressed more memory cell markers and they provided distinct adaptive immune protection. Therefore, it seems that by a previous unclear mechanism a single lymphocyte can differentiate to diverse cell fates essential for adaptive immunity.

References:

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2.          Dare to Be Different: Asymmetric Cell Division in Drosophila, C. elegans and Vertebrates. Current Biology, Vol.14, R674, 2004.

3.          Arrested Differentiation, the Self-Renewing Memory Lymphocyte, and Vaccination. Science, Vol.293, 248, 2001.