• UCSBgauchos twitter avatar
    Moreno de Alboran Advances to First ITA Southwest Regionals Singles Championship in Program History https://t.co/gFomRfFLBB
    5 hours 8 min ago
  • UCSBgauchos twitter avatar
    Gauchos Fall 1-0 at Cal State Fullerton https://t.co/PGG96WtNIF
    7 hours 45 min ago
  • ucsantabarbara twitter avatar
    A UCSB biologist examines the benefits & drawbacks of virtual & augmented reality in teaching environmental science. https://t.co/uB40WL1q0O
    8 hours 23 min ago
  • UCSBgauchos twitter avatar
    .@UCSB_Volleyball makes it three wins for the week after sweeping CSUN Saturday night! RECAP >>>… https://t.co/Y0rCoOnBi6
    1 day 5 hours ago
  • UCSBgauchos twitter avatar
    .@UCSBMensSoccer takes on UC Davis in a battle for first tonight at Harder Stadium! Tune in here:… https://t.co/Zn3WPNjEok
    1 day 8 hours ago
  • UCSBgauchos twitter avatar
    UCSB Beats PAC-12's UCLA By 14 Points https://t.co/HGdLRkF1op
    1 day 11 hours ago
  • UCSBLibrary twitter avatar
    RT @Marikhasmanyan: Reppin @UCSBLibrary with @ForestSways and @Stahlmatt at #ArchivesBazaar if you're in the area stop by for a chat and gr…
    1 day 15 hours ago
  • UCSBLibrary twitter avatar
    RT @ForestSways: Come visit @UCSBLibrary archives table at #ArchivesBazaar https://t.co/tYLQmkTjDh
    1 day 16 hours ago
  • ucsantabarbara twitter avatar
    CA Assemblymember visited #UCSB’s food pantry after adopting a $7.5 million budget to combat food insecurity. https://t.co/tlWK9TZVIL
    1 day 17 hours ago
  • UCSBgauchos twitter avatar
    No. 10 UCSB Drops Road Match to No. 8 Long Beach State, 10-6 https://t.co/vGlvB1TN23
    2 days 2 hours ago
  • UCSBgauchos twitter avatar
    Da Silveira and Dubavets Stay Afloat and Advance to Round of 16 https://t.co/ZSxtqldlOq
    2 days 3 hours ago
  • UCSBgauchos twitter avatar
    .@UCSB_Volleyball gets revenge, knocks off LBSU in four behind 26K-17D double-double from Lindsey Ruddins. RECAP >>… https://t.co/MVhhyi4I4J
    2 days 5 hours ago
  • UCSBgauchos twitter avatar
    Moreno de Alboran Shines in Day Two of ITA Southwest Regionals https://t.co/R1amVJQr0B
    2 days 5 hours ago
  • ArtsandLectures twitter avatar
    RT @sbseasons: Rhiannon Giddens Comes to Campbell Hall! 10/26 https://t.co/FyWnr2pSH7 @Sbseasons #seasonsmagazine #sb @artsandlectures @Rh
    2 days 11 hours ago
  • ucsantabarbara twitter avatar
    #GauchoAlum Navjot Brar ’16 is a founder of UCSB Startup Weekends and business analyst at Carpe Data.… https://t.co/TZeKVCz0P3
    2 days 17 hours ago

An Orchestrated Process

UCSB researchers develop a more precise and controlled method of engineering tissues from stem cells
Monday, May 15, 2017 - 11:45
Santa Barbara, CA

Tissue engineering Huang et al.jpg

NIR light for tissue engineering

Near-infrared light is used to precisely engineer stem cells into tissue

Photo Credit: 

Peter Allen illustration

Xiao Huang.jpg

Xiao Huang

Xiao Huang

Photo Credit: 

Courtesy Image

Reich and Morales2.jpg

Reich and Morales

Norbert Reich and Demosthenes Morales

Photo Credit: 

Spencer Bruttig

Nothing beats nature. The diverse and wonderful varieties of cells and tissues that comprise the human body are evidence of that.

Each one of us starts out as a mass of identical, undifferentiated cells, and thanks to a combination of signals and forces, each cell responds by choosing a developmental pathway and multiplying into the tissues that become our hearts, brains, hair, bones or blood. A major promise of studying human embryonic stem cells is to understand these processes and apply the knowledge toward tissue engineering.

Researchers in UC Santa Barbara’s departments of Chemistry and Biochemistry, and of Molecular, Cellular and Developmental Biology have gotten a step closer to unlocking the secrets of tissue morphology with a method of three-dimensional culturing of embryonic stem cells using light.

“The important development with our method is that we have good spatiotemporal control over which cell — or even part of a cell — is being excited to differentiate along a particular gene pathway,” said lead author Xiao Huang, who conducted this study as a doctoral student at UCSB and is now a postdoctoral scholar in the Desai Lab at UC San Francisco. The research, titled “Light-Patterned RNA Interference of 3D-Cultured Human Embryonic Stem Cells,” appears in volume 28, issue 48 of the journal Advanced Materials.

Similar to other work in the field of optogenetics — which largely focuses neurological disorders and activity in living organisms, leading to insights into diseases and conditions such as Parkinson’s and drug addiction — this new method relies on light to control gene expression.

The researchers used a combination of hollow gold nanoshells attached to small molecules of synthetic RNA (siRNA) — a molecule that plays a large role in gene regulation — and thermoreversible hydrogel as 3D scaffolding for the stem cell culture, as well as invisible, near-infrared (NIR) light. NIR light, Huang explained, is ideal when creating a three-dimensional culture in the lab.

“Near-infrared light has better tissue penetration that is useful when the sample becomes thick,” he explained. In addition to enhanced penetration — up to 10 cm deep — the light can be focused tightly to specific areas. Irradiation with the light released the RNA molecules from the nanoshells in the sample and initiated gene-silencing activity, which knocked down green fluorescent protein genes in the cell cluster. The experiment also showed that the irradiated cells grew at the same rate as the untreated control sample; the treated cells showed unchanged viability after irradiation.

Of course, culturing tissues consisting of related but varying cell types is a far more complex process than knocking down a single gene.

“It’s a concert of orchestrated processes,” said co-author and graduate student researcher Demosthenes Morales, describing the process by which human embryonic stem cells become specific tissues and organs. “Things are being turned on and turned off.” Perturbing one aspect of the system, he explained, sets off a series of actions along the cells’ developmental pathways, much of which is still unknown.

“One reason we’re very interested in spatiotemporal control is because these cells, when they’re growing and developing, don’t always communicate the same way,” Morales said, explaining that the resulting processes occur at different speeds, and occasionally overlap. “So being able to control that communication on which cell differentiates into which cell type will help us to be able to control tissue formation,” he added.

The fine control over cell development provided by this method also allows for the three-dimensional culture of tissues and organs from embryonic stem cells for a variety of applications. Engineered tissues can be used for therapeutic purposes, including replacements for organs and tissues that have been destroyed due to injury or disease. They can be used to give insight into the body’s response to toxins and therapeutic agents. 

Research on this study was also conducted also by Qirui Hu, a postdoctoral fellow in Dennis Clegg’s lab at UCSB’s Center for Stem Cell Biology and Engineering in the Department of Molecular, Cellular and Developmental Biology, and Yifan Lai in the lab of Norbert Reich in the Department of Chemistry and Biochemistry.

Contact Info: 

Sonia Fernandez
(805) 893-4765
sonia.fernandez@ucsb.edu

Topics: