Inflammatory Macrophages in ALS Spinal Cord

In my many conversation with Neuro-disease researchers, I often learn of discoveries that beg to be shared. I have been collaborating with Dr. Milan Fiala to explore how our hN2 Primary Human Neurons could be best used to study the role of inflammatory cytokines in amyotrophic lateral sclerosis (ALS). This would build on the excellent research he and his team are conducting at UCLA.

He shared with me that these inflammatory cytokines could be the bad actors in ALS. Specifically, in vitro, superoxide dismutase-1 (SOD-1) stimulates expression of inflammatory cytokines, including IL-1β, IL-6, and TNF-α, through activation of cyclooxygenase-2 (COX-2) and caspase-1. Further, they have discovered The lipid mediator resolvin D1 (RvD1) inhibited IL-6 and TNF-α production in ALS macrophages with 1,100 times greater potency than its parent molecule docosahexaenoic acid. ALS peripheral blood mononuclear cells (PBMCs) showed increased transcription of inflammatory cytokines and chemokines at baseline and after stimulation by aggregated wild-type SOD-1, and these cytokines were down regulated by RvD1. Thus the neurons are impacted by macrophages expressing inflammatory cytokines. RvD1 strongly inhibits in ALS macrophages and PBMCs cytokine transcription and production. Resolvins offer a new approach to suppression of inflammatory activation in ALS. To learn more see: Guanghao Liu, Milan Fiala, Mathew T. Mizwicki, James Sayre, Larry Magpantay, Avi Siani, Michelle Mahanian, Madhuri Chattopadhyay, Antonio La Cava, and Martina Wiedau-Pazos. Neuronal phagocytosis by inflammatory macrophages in ALS spinal cord: inhibition of inflammation by resolvin D1.
Am J Neurodegener Dis. 2012;1(1):60-74.

Images: Co localization of TNF-a- and IL-6- expressing macrophages with caspase-3-and the chemokine RANTES (CCL5) – stained neurons in ALS and control spinal cords. Frozen sections of ALS and control lumbar spinal cord were stained with anti-NeuN (red), anti-CD68 (green), anti-caspase-3 (magenta) or anti-RANTES (magenta), and DAPI (blue) (Immunofluorescence microscopy (20X)). The experiment was repeated with 2 other ALS spinal cords and 2 other control spinal cords and yielded comparable results.
Photomicrographs are shown in 2 patients (A, B, C, D) and 2 controls (E, F). (A) Co
localization (yellow) of TNF-a-positive (magenta) and (CD68-positive, green) macrophages with NeuN–positive (red) neurons; (B) Co localization (yellow) of IL-6-positive (magenta) and CD68-positive (green) macrophages with NeuN–positive (red) neurons; (C) Co localization of macrophages (CD68-positive, green) with apoptotic, caspase-3-positive (magenta) and non-apoptotic (caspase-3-negative (red)) neurons. Eight neurons are impacted by macrophages; 3 neurons are caspase-3-positive (arrows) and 5 neurons are caspase-3- negative (asterisk); (D) Co localization of macrophages (yellow) with RANTES-positive (magenta) and CD 68-positive (green) macrophages with NeuN-positive (red) neurons. (E&F) No macrophages (green) are detected in 3 control spinal cords. (G&H) The table shows that in three ALS spinal cords 19.2 +/−4.8% NeuN-positive (red) neurons co localize with TNF-a -positive (magenta) macrophages (green) and 18.5 +/− 4.9 % NeuN-positive (red) neurons co localize with IL-6-positive (magenta) macrophages (green), whereas in control spinal cords 0% neurons (red) co localize with macrophages (green).

I will keep you posted on progress.

Umbilical-Cord Matrix Stem Cells and Cerebral Ischemia

I am winding down on the stem cell story for now as later in the month I will be featuring my good friends at University of Sherbrooke and their research in the area of chronic pain.

I did want to highlight yet another potential application for stem cells. For this, we send kudos to Dr. Yan Xu and his colleagues at University of Pittburgh for their findings on inflammatory response in Golbal Ischemia. Their work was recently published:

Aaron Hirko, Renee Dallasen, Sachiko Jomura, Yan Xu. Modulation of Inflammatory Responses after Global Ischemia by Transplanted Umbilical-Cord Matrix Stem Cells. Stem Cells First published online August 21, 2008; doi:doi:10.1634/stemcells.2008-0075

Secondary to Cardiac Arrest is Brain Damage do to lack of blood flow. This is marked by a delayed loss of Neurons in CA1 hippocampus region of the brain due to inflammatory response.

The story timeline of this response is good then bad with interesting twists. The delay in neuronal loss is linked to initial inflammation. It involves both reactive astrocytes (astrocytosis) and glia. Delaying the loss is, of course, good.

…But then, the reactive astrocytosis and related glial scarring cause a physical and biochemical barrier to regeneration of neurons…a bad thing. Protecting the microglia is a good thing, because they these cells serve as scavengers for clearing the cellular debris. They can also secrete a variety of cytotoxic and protective chemicals.

The wow factor in this research is that  implanted rat umbilical-cord matrix (RUCM) cells can provide partial protection against neuronal injury in rat brains. Rats treated with RUCM cells three days prior to an 8-min CA had only 25-32% neuronal loss in the hippocampal CA1 region compared to the typical 50-68% neuronal loss observed in the untreated or the vehicle-treated animals. This could be due to to the favaorable modulation of the “good-bad” inflammatory response.

The good news in the search for therapies for stroke and cardiac arrest victims is combined, stem-cell-like RUCM cells offer protection against neuronal injury after global cerebral ischemia by enhancing the survivability of the astroglia in the selectively vulnerable regions.

We are pleased that the research team used our GFAP antibody as an marker for astrotytic in their studies.