Talk:SH Lecture - Lymphatic Structure and Organs

From Embryology

Pubmed Bookshelf

Search PubMed Databases immune system

2011

Start Time/End Time: 10am to 11am Monday 28 February 2011 Clancy Auditorium eMed Link to Learning Activity - Lymphatic organs histology


Bookshelf links

old - http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=mboc4&part=A4419&rendertype=figure&id=A4423 MBoC Figure 24-3 Human lymphoid organs

new - http://www.ncbi.nlm.nih.gov/books/NBK26921/figure/A4423 MBoC Figure 24-3 Human lymphoid organs

Recent Research

Defining the quantitative limits of intravital two-photon lymphocyte tracking

Proc Natl Acad Sci U S A. 2011 Jul 26;108(30):12401-6. Epub 2011 Jul 6.

Textor J, Peixoto A, Henrickson SE, Sinn M, von Andrian UH, Westermann J. Source Institute for Theoretical Computer Science, University of Lübeck, 23562 Lübeck, Germany. textor@tcs.uni-luebeck.de

Abstract

Two-photon microscopy has substantially advanced our understanding of cellular dynamics in the immune system. Cell migration can now be imaged in real time in the living animal. Strikingly, the migration of naive lymphocytes in secondary lymphoid tissue appears predominantly random. It is unclear, however, whether directed migration may escape detection in this random background. Using a combination of mathematical modeling and experimental data, we investigate the extent to which modern two-photon imaging can rule out biologically relevant directed migration. For naive T cells migrating in uninfected lymph nodes (LNs) at average 3D speeds of around 18 μm/min, we rule out uniform directed migration of more than 1.7 μm/min at the 95% confidence level, confirming that T cell migration is indeed mostly random on a timescale of minutes. To investigate whether this finding still holds for longer timescales, we use a 3D simulation of the naive T cell LN transit. A pure random walk predicts a transit time of around 16 h, which is in good agreement with experimental results. A directional bias of only 0.5 μm/min-less than 3% of the cell speed-would already accelerate the transit twofold. These results jointly strengthen the random walk analogy for naive T cell migration in LNs, but they also emphasize that very small deviations from random migration can still be important. Our methods are applicable to cells of any type and can be used to reanalyze existing datasets.

PMID 21734152

http://www.pnas.org/content/108/30/12401.full

Stromal cell contributions to the homeostasis and functionality of the immune system

Nat Rev Immunol. 2009 Sep;9(9):618-29. Epub 2009 Jul 31.

Mueller SN, Germain RN. Source Department of Microbiology and Immunology, The University of Melbourne, Parkville, 3010 Victoria, Australia. smue@unimelb.edu.au Abstract A defining characteristic of the immune system is the constant movement of many of its constituent cells through the secondary lymphoid tissues, mainly the spleen and lymph nodes, where crucial interactions that underlie homeostatic regulation, peripheral tolerance and the effective development of adaptive immune responses take place. What has only recently been recognized is the role that non-haematopoietic stromal elements have in many aspects of immune cell migration, activation and survival. In this Review, we summarize our current understanding of lymphoid compartment stromal cells, examine their possible heterogeneity, discuss how these cells contribute to immune homeostasis and the efficient initiation of adaptive immune responses, and highlight how targeting of these elements by some pathogens can influence the host immune response.

PMID 19644499

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2785037

http://www.nature.com/nri/journal/v9/n9/abs/nri2588.html