Modified mesenchymal stem cells for brain remodeling and motor recovery in a rodent stroke model

2019 Fiscal Year Research-status Report

• Project/Area Number: 18K16577
• Research Institution: University of Tsukuba
• Principal Investigator: プエンテス サンドラ 筑波大学, システム情報系, 助教 (00725765)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: Stroke / Mesenchymal stem cells / Microglial polarization / Ischemic penumbra

Outline of Annual Research Achievements

This fiscal year, we focused on increasing the number of animals per each group. The goal was to acomplish 6 animals per each cell condition (mesenchymal stem cells with and without microvesicles, from baby or adult adipose tissue, endothelial progenitor cells (EPCs)) and the control group (phosphate buffer saline). Additionally we realised than an additional group is required, so we started preparing for injecting a new group using EPCs derived microvesicles only. All mice included in the study underwent transient middle cerebral artery occlusion (reperfusion after 1h) and were evaluared by using the Longa score (behavioral analysis); only animals scoring 3-4-5 were selected (moderate impairment). After ending the experiment, brains were collected and processed for histology and immunohistochemistry. Our microglia polarization stainings has shown that the transplant of baby adipose mesenchymal stem cells induces neuroprotective microglial polarization when compared with control and other cells groups. Vascular and astrocutic staining comparisons has not shown marked differences but the cell counting has not been completed. Also the neuron counting is still undergoing.
Statistical analysis is still pending since animal surgeries and sample collection is not finished yet.

Current Status of Research Progress

3: Progress in research has been slightly delayed.

Reason

In our initial plan, we were planning to run in vitro and in vivo experiments at the same time studying the effect of our groups of cells in oxygen glucose deprivated neurons and nice after infarct induction. However, the interesting finding related to microglia polarization motivated us to change our plan. Initially we want to confirm which cells has the most effect in microglial polarization (almost finished) and then within this year we will prepare for the in-vitro part of our study.

Strategy for Future Research Activity

We will finish histology and immunohistochemistry for the remaining samples. Additionally, we are already undergoing experiments to complete the microvesicles group. Then cell counting will be performed and statistical analysis will bbe done. We are also planning for this year to perform in vitro experiments to support the results we had for the transplanted mice. PCR and ELISA may be the selected tools for running such experiments.

Causes of Carryover

The non-used part is related to in vitro experiments. This budget part was supposed to be invested in culture reagents and culture disposables. Since in vitro experiments will be starting within this fiscal year, the plan is to carry over the budget so it can be used this year as planned before.