Navigation Links
What composes the human heart? U of T researchers crunch the numbers

A foundational study published in top biomedical journal PNAS (Proceedings of the National Academy of Sciences) this week by researchers at the University of Toronto's Institute of Biomaterials & Biomedical Engineering (IBBME) and the McEwen Centre for Regenerative Medicine have identified the optimal structure and cell ratio associated with heart function and the discovery has already led the team to another research first: the engineering of the first-ever living, three-dimensional human arrhythmic tissue.

The study marks the first time that researchers have tried to define and formulate the precise type and ratio of cell types that produce highly functional cardiac tissue.

"Hearts are not just composed of one type of cell," explained fourth-year IBBME PhD Student Nimalan Thavandiran and first author of the PNAS study. But until now, scientists have not known how to mix different cell types in engineered heart tissue in such a way that the tissue achieves the composition and maturity level of the native human heart.

Thavandiran solved this mystery by methodically separating out different cell types derived from human pluripotent stem cells and precisely mixing them back together. Using scoring metrics associated with functional hearts - contraction, electrical activity and cell alignment Thavandiran was able to develop a formula for engineering highly functional heart tissue.

The composition of the cells is vital," stated Thavandiran. "We discovered that a mixture of 25% cardiac fibroblasts (skin-like cells) to 75% cardiomyoctes (heart cells) worked best." The carefully composed cell ratios were then grown in three-dimensional "wires" that mimic the structure of human heart tissue.

"An exciting result of our study is our ability to miniaturize the tissues into human heart micro-tissues that can be used to measure normal and diseased human heart responses to drugs," emphasized Professor Peter Zandstra, corresponding author of the study and Canada Research Chair in Stem Cell Bioengineering at IBBME and the McEwen Centre for Regenerative Medicine.

From discovering the right composition of heart cells, the researchers next designed the first-ever three-dimensional arrhythmia tissue model.

Millions of people experience arrhythmia each year, a condition in which the feedback of electrical pulses of the heart is interrupted, leaving the heart unable to contract and pump blood effectively.

With the right cellular composition, though, the researchers were able to engineer the circular tissue model associated with arrhythmia. The team then applied electrical pulses to the arrhythmic tissues, 'zapping' the irregularly beating tissue into a state of regular contractions.

Since human heart cells aren't easily grown, being able to engineer highly functional heart tissue from human stem cells is a vital concern for cardiac researchers.

"We can now combine this compositional knowledge with electrical stimulation and mechanical stimulation to obtain a truly biomimetic system necessary for cardiac research," cited corresponding author Associate Professor Milica Radisic, core faculty at IBBME and the Department of Chemical Engineering and Applied Science, and Canada Research Chair in Functional Cardiovascular Tissue Engineering.

Stressing the urgent need for highly functional heart tissue to perform important drug screening research, Thavandiran added, "We're making a really big push to bring this model to the marketplace."

The team has been working with the Centre for the Commercialization of Regenerative Medicine (CCRM) to commercialize their tissue modeling platform.


Contact: Erin Vollick
University of Toronto

Related medicine news :

1. Predicting human body height from DNA
2. The human health costs of losing natural systems: Quantifying Earths worth to public health
3. China Human Vaccine Industry Report, 2012-2015
4. Mahendra Trivedi Announces the New Master During the Historical Event “Transforming Humanity”
5. NHS Human Services Foundation to Host 10th Annual Leading the Way Awards Gala
6. Geranylgeraniol suppresses the viability of human prostate cancer cells and HMG CoA reductase
7. Tel Aviv University part of team launching global Human Brain Project
8. Western University of Health Sciences’ Gala Fundraiser Emphasizes Humanism and Caring
9. Animal, human health benefits anticipated from universitys premier biomedical instrument
10. ENT and Allergy Associates, LLP® Adds Resources to Its Human Resources Department, Welcomes Eric M. Saidel, JD as Its New HR Director
11. Human Circuit Completes Town of Vienna’s Council Chambers and Live Cable TV Broadcasting Project
Post Your Comments:
(Date:11/30/2015)... ... November 30, 2015 , ... Holcomb ... the leading plastic surgery practices in Florida, is proud to announce that Dr. ... surgical innovations giant Ethicon Inc., a Johnson & Johnson Company. , Ethicon is ...
(Date:11/30/2015)... ... November 30, 2015 , ... The successful filing of an Investigational New Drug ... so important to this key industry segment, Regis Technologies has decided to sponsor and ... 4th at 11am EST. , Federal law does not allow new drugs to cross ...
(Date:11/30/2015)... ... November 30, 2015 , ... Healthjump, Inc. ... Inc., a Healthcare IT consulting, development and support company. The purchase will expand ... available within DataTrade to extend the services currently provided by Healthjump. ...
(Date:11/30/2015)... ... November 30, 2015 , ... GKhair & Tibolli team members and artists were ... held on November 8th and 9th at the Puerto Rico Convention Center, San Juan ... beauticians and top of the line fashion journalists. The San Juan Beauty Show carries ...
(Date:11/30/2015)... ... 2015 , ... Innovaacom, a leading provider of medical education ... of educational needs for pharmacists worldwide. The poll of pharmacists in Europe, Asia, ... online and face-to-face education for pharmacists who are fast becoming the new “gatekeepers” ...
Breaking Medicine News(10 mins):
(Date:11/30/2015)... HANOVER, N.J. , Nov. 30, 2015  Novartis ... portfolio at the 57 th American Society of ... leukemias, lymphomas and myelomas as well as supportive care, ... in addition to personalized cell therapies. The ASH Annual ... Orlando, Florida . Novartis Oncology . ...
(Date:11/30/2015)... and BOSTON , November 30, 2015 ... develop potential new medicines directed at up to 10 ... --> PFE ) to research and develop ... protein-coupled receptor (GPCR) targets across multiple therapeutic areas. ... drug discovery and development company and wholly-owned subsidiary of ...
(Date:11/30/2015)... 2015 Elbit Imaging Ltd. (TASE, ... today that it was informed by InSightec Ltd. ("InSightec"), that ... has approved its Exablate Neuro system to treat movement, ... --> Insightec,s Exablate Neuro platform is transforming ... two technologies: Focused Ultrasound, which is used to lesion ...
Breaking Medicine Technology: