Advances in the Study of Neuroinflammation

Dear Colleagues,

For some time, it has been known that neuroinflammation is a complex multicellular process that plays a central role in a variety of neurological diseases, including acute inflammation, such as bacterial meningitis, as well as chronic inflammation in the form of neurodegenerative diseases or psychiatric and immune-mediated disorders. Numerous findings indicate that neuroinflammation can promote the progression of these disorders. In particular, the function of glial cells (astrocytes and microglial cells) and their activation, as well as the connection with immigrated immune cells in disease, are of great interest. The blood–brain barrier and the lymphatic pathways, as important sites of communication between the periphery and the CNS, have also become the focus of scientific investigations. As a result, there has been an explosion of interest in neuroinflammation and the tools available to study these processes in the brain.

This Special Issue seeks papers covering a wide range of topics related to studies of acute or chronic neuroinflammation, which show the developments of new models or therapeutic approaches and new objects, as well as the roles of interesting factors and glial cells in various disorders.

The article, which can focus on a topic of your choice, can be written in the form of a comprehensive review, an original article, or another type of article.

Prof. Dr. Lars Ove Brandenburg
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Cells is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• neuroinflammation
• neurodegenerative disease
• bacterial meningitis
• glia cell
• microglial cell
• macrophage
• astrocyte
• blood–brain barrier
• meninges
• meningeal immunity
• meningeal lymphatic vessels

• Study around Neuroinflammation—Series 3 in Cells (3 articles)

Title: The Formyl Peptid Receptor ligand Ac2-26 improves the integrity of the blood brain barrier in the course of pneumococcal meninigitis
Authors: Johannes Deutloff1, Irina Pöhner1, Simone C. Tauber2 and Lars-Ove Brandenburg1,#
Affiliation: 1 Institute of Anatomy, Rostock University Medical Center, Rostock, Germany 2 Department of Neurology, RWTH University Hospital Aachen, Aachen, Germany
Abstract: The brain is protected from invading pathogens by the blood-brain barrier (BBB) and the innate immune system. However, the bacteria have found and developed ways of overcoming the BBB and penetrating into the cerebrospinal fluid space and the brain to cause bacterial meningitis, which is serious for the person affected. The pattern recognition receptors are of particular importance for the detection of bacteria and the induction of the innate immune response. This included the G-protein-coupled formyl peptide receptors (FPR), which are expressed by immune cells of the central nervous system. FPR have a broad spectrum of ligands, including anti- and pro-inflammatory ligands. In this study we investigate the influence of the ligand on the integrity of the BBB in the course of penumococcal meningitis. Wildtype (WT) and Fpr1- and Fpr2-deficient mice were intrathecally infected with Streptococcus pneumoniae D39 (type 2). Subsequently, the different mice groups were treated by intraperitoneal injections of Ac2-26 (1 mg/kg body weight) 2, 8, and 24 h post-infection. The integrity of the BBB was analyzed by means of different markers using immunohistochemistry and immunofluorescence 30 h post-infection. The results showed the reduced integrity of the BBB over the course of bacterial meningitis. Ac2-26 treatment of WT mice results in a significantly longer maintenance of the BBB integrity. In the FPR1 and FPR2 deficient mice, this effect could not be detected. In conclusion, this study extends the previous findings on the anti-inflammatory properties of Ac2-26 by demonstrating that Ac2-26 positively affects the components and integrity of the BBB via the FPR in the course of pneumococcal meningitis. This may encourage further investigation of Ac2-26 and other FPR modulators as novel therapies against Streptococcus pneumoniae-induced meningitis.