Local Attachment Explains Small World-like Properties of Fibroblastic Reticular Cell Networks in Lymph Nodes.

Kasper M W Soekarjo,Johannes Textor,Rob J De Boer

doi:10.4049/jimmunol.1801016

Kasper M W Soekarjo, Johannes Textor + Show 1 more

Open Access

https://doi.org/10.4049/jimmunol.1801016

Copy DOI

Abstract

Fibroblastic reticular cells (FRCs) form a cellular network that serves as the structural backbone of lymph nodes and facilitates lymphocyte migration. In mice, this FRC network has been found to have small-world properties. Using a model based on geographical preferential attachment, we simulated the formation of a variety of cellular networks and show that similar small-world properties robustly emerge under such natural conditions. By estimating the parameters of this model, we generated FRC network representations with realistic topological properties. We found that the topological properties change markedly when the network is expanded from a thin slice to a three-dimensional cube. Typical small-world properties were found to persist as network size was increased. The simulated networks were very similar to two-dimensional and three-dimensional lattice networks. According to the used metrics, these lattice networks also have small-world properties, indicating that lattice likeness is sufficient to become classified as a small-world network. Our results explain why FRC networks have small-world properties and provide a framework for simulating realistic FRC networks.

Highlights

This indicates that results do not depend on the maximal connection length. These results show that geographical preferential attachment is sufficient to generate a topologically realistic fibroblastic reticular cell (FRC) network
As lymphocytes follow the edges of the FRC network to migrate through the lymph node [27], the average shortest path length gives insight into the distance lymphocytes need to travel to traverse the network
We studied topological properties of general cellular networks and compared them to the FRC network, both in thin slices and networks expanded to symmetric 3D cubes

Summary

Introduction

To quantify small worldness in single-size networks, several metrics have been developed based on comparing the clustering coefficient and path length of the observed network with that of a random or lattice network with the same number of nodes and edges [23,24,25]. This parameter incorporates the average shortest path length of the equivalent lattice network to determine whether a network is small world or not.

Results

Conclusion