Related Experiment Video
Updated: Aug 8, 2026
Analysis of Lymphocyte Extravasation Using an In Vitro Model of the Human Blood-brain Barrier
Published on: April 5, 2017
Analysis of leukocyte extravasation across the blood-brain barrier: conceptual and technical aspects
Melissa K Callahan1, Richard M Ransohoff
1Department of Neurosciences, Cleveland Clinic Foundation, 9500 Euclid Ave, Cleveland, OH 44195, USA.
Insights
The central nervous system (CNS) is immune competent, not privileged. Chemokines guide leukocyte migration into the CNS through distinct steps, interacting with unique CNS features like the blood-brain barrier.
Area of Science:
- Neuroimmunology
- Cellular Biology
Background:
- The central nervous system (CNS) was traditionally viewed as immunologically privileged.
- Emerging evidence suggests the CNS is immune competent, exhibiting atypical immune responses.
Purpose of the Study:
- To review the distinct steps of leukocyte trafficking into the CNS.
- To elucidate the role of chemokines in guiding leukocyte migration across the blood-brain barrier.
Main Methods:
- Review of existing literature on leukocyte trafficking and chemokine function in the CNS.
- Analysis of CNS-specific anatomic and physiologic attributes influencing immune cell migration.
Main Results:
- Leukocyte migration into the CNS involves several discrete steps, similar to peripheral organs.
- Chemokines play a crucial role in governing leukocyte extravasation into the CNS.
- Unique CNS features, including the blood-brain barrier, modulate chemokine interactions.
Conclusions:
- The CNS's immune competence necessitates a detailed understanding of leukocyte migration mechanisms.
- Considering individual stages of extravasation is key to elucidating CNS immune responses.
- Further research into stage-specific mechanisms will advance neuroimmunology.
Abstract:
The central nervous system (CNS) has long been described as an immunologically privileged organ. However, evidence is accumulating that the CNS is more adequately described as immune competent, albeit atypical. Leukocyte trafficking into the CNS in response to inflammation, as in peripheral organs, occurs in several distinct steps. As with all leukocyte trafficking, the overall process is governed in part by chemokines. The CNS has unique anatomic and physiologic attributes, including the blood-brain barrier. These characteristic features of the CNS interact with a distinct array of chemokines, expressed both constitutively and in response to inflammation. In this review, we consider the potential sites of chemokine action in guiding leukocyte migration. The process of extravasation can usefully be regarded as comprising individual steps. This review is focused on the need to consider these stages separately, and the elucidation of mechanisms at each stage is outlined.
Related Concept Videos
00:49The Blood-brain Barrier
01:22Cerebral Edema ll: Pathophysiology