Through their lens: Yimin Yang learns how to unlock the secrets of HIV

This summer we’re sponsoring high school interns in stem cell labs throughout California. We asked those students to contribute to our Instagram photos and YouTube videos about life in the lab, and write about their experiences. 

Yimin Yang worked in the lab of Drs. Anderson and Sharlie Barclay at the UC Davis Institute for Regenerative Cures. 


Hello, my name is Yimin Yang, and I will be a senior at Davis Senior High School this upcoming fall. For the past two months, I have been interning at the UC Davis Institute for Regenerative Cures under the instruction of my mentors Dr. Anderson and Sharlie Barclay. I am currently working on the HIV Team, which seeks to develop an effective treatment for HIV through stem cell gene therapy. Since all the cells that HIV targets come from hematopoietic stem cells (HSCs), stem cell gene therapy could help treat and possibly cure patients with HIV.

For my project, I am testing the efficacy of a triple combination anti-HIV lentiviral vector. The vector is comprised of four parts: a CCR5 shRNA, a chimeric TRIM5α protein, a TAR decoy, and a CD25 pre-selective marker. The CCR5 shRNA binds to the mRNA of CCR5, a co-receptor that HIV needs to fuse its viral envelope with the plasma membrane, and prevents it from being translated into protein. This down-regulates the expression of CCR5 on the cell surface, thus impeding HIV’s entry into the cell. The chimeric TRIM5α targets the pre-integration and post-entry stages of the HIV life cycle, interfering with the process by which the virus uncoats its capsid. The TAR decoys bind to TAT proteins and inhibit the TAT-TAR interactions which play an integral role in effective transcription of HIV. Finally, the CD25 pre-selective marker helps us select for the cells which been transduced.

To test for the efficacy of this vector, my mentors and I challenged transduced macrophages with HIV-1 and measured the levels of P24 at various time points over a period of four weeks. When we compared these results to the control, we found that the transduced macrophages had successfully developed resistance to HIV. We also tested for CCR5 down-regulation in GHOST cells through flow cytometry; this too yielded encouraging results as CCR5 expression was significantly lower in transduced cells as opposed to nontransduced controls.

In addition to the efficacy experiments, I also spent time in the lab helping to produce more of the vector. I made LB broth for bacteria cultures, extracted plasmids, and transfected HEK-293T cells. From performing these protocols, I gained valuable insight into what it is like to work in a professional research facility. I learned how important it is to have good sterile technique and work efficiently. This internship has also opened my eyes to the fascinating world of stem cell research through the BIO225 class that we had to take as a part of the program. Although I had some basic knowledge regarding stem cells, I was still unaware of the wide range of potential applications they had in the medical field. Outside of tissue repair and regenerative medicine, stem cells could also be utilized in gene therapy to treat for genetic and infectious diseases. Overall, this course has not only helped to reinforce my understanding of the topic from my work in the lab, but also introduced me to a variety of new, exciting concepts.

As I had often considered pursuing a career as a research scientist, this experience has certainly cemented my interest in the field and given me a clearer vision of the path I wish to follow in the future.

I would like to thank Dr. Bauer and my mentors, Dr. Anderson and Sharlie Barclay, for all the help and guidance they have given me. I am also incredibly grateful to CIRM, the UC Davis Stem Cell Program, and everyone else who made the Creativity Program possible, as my internship this summer has been completely amazing and utterly unforgettable.

Yimin Yang

Huffington Post documents the “Dark Age for Science”

Labs are facing closure because of NIH budget cuts 

In the past few months we have written a few times about the impact the federal budget cuts known as the sequestration are having on medical research. Those posts are here.

Today the Huffington Post did a good — and depressing — job of showing the impact of those cuts on research teams around the country and on the potentially life-saving work those team are trying to complete. The reporter interviewed more than two dozen researchers and academic administrators and they told a uniform story of despair caused by years of flat budgets for the National Institutes of Health followed by this year’s $1.7 billion cut from the sequestration.

The piece written by Sam Stein documents our country’s lost investment in researchers, research equipment and promising research projects that are increasingly being idled, frozen in place for now. It raises the specter of many of these teams not being resurrected and a resulting brain drain ending our nation’s dominance in medical research.

Stein quoted Steven Warren, the vice chancellor for research at the University of Kansas, who was talking at a recent meeting of academic officials in Washington:

“It is like a slowly growing cancer. It’s going to do a lot of destruction over time.”

Private groups are stepping up to help bridge promising projects over these current gaps in funding. The American Society of Hematology (ASH) today announced the second round of funding for projects that had been deemed worthy by NIH peer review panels, but had fallen below the cutoff in today’s funding climate. A press release from ASH was widely disseminated by online new portals including Reuters.

The problem is some 700 projects fall into that same worthy-but-unfunded limbo at NIH. ASH funded 12 today and hopes to fund up to 30. The gap is too large for private groups to close. States can potentially have a bigger role and a few have significant research funding streams, but none as robust as California’s through CIRM. You can read about our funding here.

The academic community has turned up its efforts to get the budget cuts reversed. Recently, 165 professors and college presidents wrote to President Obama and members of Congress asking them to take action now. Let’s hope they get a good response soon.

Don Gibbons

Through Their Lens: Maya Varma’s First Laboratory Experience a Life-Changing Experience

This summer we’re sponsoring high school interns in stem cell labs throughout California. We asked those students to contribute to our Instagram photos and YouTube videos about life in the lab, and write about their experiences. 

Maya Varma worked in the lab of Dr. Gerhard Bauer at the UC Davis Institute of Regenerative Cures. Bauer directs UC Davis’ state-of-the-art Good Manufacturing Practice (GMP) facility.

Maya Varma gained experience this summer working with stem cells in
the very sterile conditions of UC Davis’ Good Manufacturing Practice (GMP) facility.

When I first started my internship eight weeks ago, I had never worked in a laboratory before. I did not know much about stem cells either, besides the brief overview presented in my freshman biology class. But, from the very first day that I walked into the lab, I knew that it would be a life-changing experience for me. In less than a few days, I learned how to pipette and centrifuge solutions in a sterile manner. I witnessed a stem cell-based clinical trial taking place. I was taught how to gown and de-gown appropriately for work in the GMP. To the scientists working here, these are routine procedures that occur daily. But to me, it was the first time that I had ever participated in such laboratory work, and I was fascinated.

Over the next few weeks, I eagerly began work on my project, utilizing the sterile technique that I had been taught. My project is focused on the use of lentiviral vectors to create GMP-grade induced pluripotent stem cells from adult fibroblast cells through upregulation of the four reprogramming factors – OCT4, SOX2, KLf4, and C-Myc. Lentiviral vectors are HIV-based gene delivery vehicles that can integrate DNA into cells. Through HEK-293T producer cell culturing, transfection of necessary plasmids, harvesting of vectors, and transduction into human fibroblasts cells, I was able to successfully create induced pluripotent stem cells.

I was also fortunate enough to attend a stem cell presentation by CIRM science officer Dr. Uta Grieshammer and researcher Dr. Jill Helms at a science museum in San Jose. They outlined the importance of stem cells and their potential in the medical industry in the coming years. Perhaps the most important lesson I learned is that research takes time and absolute dedication. The researchers that I work with are completely committed to their work, coming into the office daily and working long hours. The high-quality sterile products created in the GMP reflect their patience and enthusiasm for advancing the frontiers of stem cell research. Every day, their research and new discoveries are paving the way.

I greatly enjoyed my internship, and I am extremely sad that it is almost over. I have learned so much about stem cells, and about the groundbreaking research that is currently taking place in this lab. My experiences have helped me to become proficient at sterile lab technique, include cell culturing, transfection and transduction, and qPCR assays. This was definitely a wonderful opportunity for me, and I look forward to continuing lab work and research in the future. I would like to thank the California Institute for Regenerative Medicine, the UC Davis Institute of Regenerative Cures, Dr. Jan Nolta, the GMP facility researchers, and my mentor, Dr. Gerhard Bauer, for providing me with this wonderful experience that I will always remember as my first stepping stone to becoming a researcher in the future.

Maya submitted two video during her internship. You can watch them here and here

Maya Varma

Maya submitted this video about her experience: