Visualizing the pathological intricacies of hearing loss

Always ready to learn, inside and outside the lab 

Ivan Lopez, PhD, Director and Adjunct Professor 

Ivan Lopez, PhD became enamored with the hair cells in the ear four decades ago and remains dedicated to advancing the understanding of hearing loss. After growing up and completing his undergraduate and graduate education in Mexico, he relocated his growing family to Los Angeles and began his academic career at the University of California, Los Angeles (UCLA). As an Adjunct Professor and Director of the Cellular and Molecular Biology of the Inner Ear Laboratory, he specializes in hearing science. 

Why did you decide to go into science? 

When I was six years old in Mexico, my father, a physician, gave me a microscope. He took me to a park with a small fountain to grab a water sample, and when I looked at it under the microscope, I saw paramecia moving around. It was then that I decided I wanted to be a scientist. Of course, I always saw all my dad’s books about biochemistry and medicine in my house. When I was in middle school and high school, I was fascinated with chemistry, which became my educational focus. My aunt was a researcher at what is now the biggest university in Latin America—the National Autonomous University of Mexico (UNAM)—with 300,000 students. In the 1980s, they had a small research institute. There I found a doctor who asked me to do research in his lab when I was 22 years old, and I immediately said yes. That was where I first saw and fell in love with the hair cell of the ear.  

How did you decide to leave Mexico and come to UCLA? 

I was at the same university (UNAM) earning my BS (Chemistry), MS (Biochemistry), specialty training (electron microscopy; EM), and my PhD (Biochemistry). In 1986, my master’s degree mentor, who was very savvy at getting foreign professors to visit her lab, invited someone who would change my life. This man, who was in Mexico to see the World soccer games, was impressed by my hand skills, and invited me to come to UCLA after I finished my doctorate. I said, “No, no, no, I don’t want to go LA—I will be going to Germany to do my postdoc.” He came back every year to ask again. Although I had been accepted by a postdoctoral fellowship program in Germany, I was married and had a son by then. My wife convinced me that moving to Germany for a short time to then returning with no guaranteed job was risky, so I accepted the long-term offer at UCLA. I started as a postdoc, transitioned to a researcher, and then ultimately became a professor. This year, I’m proud to say I’ve been an employee of UCLA for 30 years, where I’m well recognized for my experience and dedication. 

Did you know English before you moved here? 

I knew what I heard in the movies. But my father always encouraged my brother and me to take classes instead of wasting time. So, we took some English classes when we were 12 or 13, and I think that helped me a lot. Then, at the undergraduate science level, most of the books were in English, including the very thick and famous Principles of Biochemistry by Lehninger. But even today, when I have a conversation in English outside of my field of work, I have difficulties.  

What do you think is a good formula for making progress in science? 

Our department has a tradition of having PhDs working with medical doctors. That means I’ve always had the opportunity to interact with physicians and be able to integrate the concepts of molecular pathology, chemistry, and biochemistry that I learned from basic research into the disease. It’s mind-blowing for me because early in my career things were not as intermingled: medicine was kept in one arena and science was kept in another. Now we know they cannot live or progress without the other.  

What’s the most stunning change in the sciences you’ve seen?  

Most recently, with the pandemic, we saw the development of the mRNA vaccine. I never thought this would be possible with the science we were doing in the 80s and 90s. But, because of the necessity and the funding that became available, we had vaccines and therapeutics available in months rather than years. That’s a big jump. Many other amazing things are happening right now. For example, integrating artificial intelligence into the picture and seeing what we can learn from the “connectomics” Brain Research Through Advancing Innovative Neurotechnologies® (BRAIN) Initiative to study the brain’s structural and functional connections between cells. With all the changes and multidisciplinary aspects, I know that I must reinvent myself to keep up. I’m not scared—I’m excited because I always go for the challenge. But the electron microscopy techniques that I learned early in my career are still relevant. Sample preparation is still essential. Some distinguished professors tell me that I have specific skills to handle tissue samples so well that it makes me unique. I’m like the French chef or sushi master who brings something special to the table.  

How would you describe what you do in 30 seconds or less if someone met you on the elevator? 

Briefly, I am a scientist. I do research in hearing to help people hear better. And then, if they have the time to listen, I will tell them more about my current research. I study the histopathology of the human ear, trying to discern the molecular basis of disease. We teach residents, medical doctors, medical students, and undergrads how the ear is organized. The ear is one of the more marvelous architectures in your body and it affects hearing and balance. Our ears suffer damage as we are exposed to noise, chemicals, antibiotics, and more. I focus on understanding how hearing is affected. For that, we rely on a temporal bone bank (National Temporal Bone, Hearing, and Balance Resource Registry) established in 1960 by the National Institute of Deafness and other Communication Diseases (NIDCD), with access to an archive of 12,000 temporal bones from human donors with different diseases. We can do different types of analysis from DNA to proteomics, immunocytochemistry, or electron microscopy to better understand how different situations affect the ear. For example, we have a collection of samples from people with noise-induced hearing loss and from people who received a cochlear implant. We are trying to create a three-dimensional model from hundreds of thousands of slices so that you can see the normal ear compared with the pathological ear under different conditions and think that we can do that in 5 years.  

What are the primary causes of hearing loss?  

The problem with hearing loss is that almost everything causes damage. The 30,000 cells we are born with are tiny and begin to decay around age 20. Continuous noise exposure is one unavoidable reason you will lose hearing. Loss can also occur if you have an infection that requires the use of antibiotics effective against gram-negative bacteria. Even a common drug like aspirin (salicylate) can affect the inner or outer hair cells. Genetics is also a factor: people can be completely deaf at birth or express the defect with time. Deafness severely affects the ability to communicate, propagates brain shrinkage, and can lead to neurodegenerative diseases. There’s so much more to learn.  

What do you see yourself doing in another 5 to 10 years? 

Science develops at such a fast pace, and I am expanding my horizon outside of balance and hearing. I’m beginning to study the retina and the sensory olfactory system. In 2020, I worked on a review on the loss of smell (anosmia) associated with COVID-19 that ended up being one of my most popular papers with about 16,000 downloads and 60 citations. Recently, I was invited to participate in the BRAIN Initiative because of my EM skills (transmission and scanning electron microscopy). I also want to learn about artificial intelligence. I believe I should continue diversifying my portfolio. I will be happy to continue my research and teaching for 10 or 15 years more while I’m still in good shape. 

What is the most rewarding or challenging facet of your research? 

Among the rewarding things, people are extremely supportive of you, your discoveries, and what you are contributing to science. On a personal level, I enjoy finding new details in the cells using the electron microscope and mentoring students. I like teaching and motivating students to do more. One of my MD-PhD students tells me that his interest and accomplishments are because of me. That’s the kind of thing that is the best food for a scientist. It helps offset the main challenge we must face as a public university that is reliant on grant funding. But if you are in this game, you learn to be prepared for rejection, to be persistent, and to provide new ideas. This is everybody’s challenge, not only mine. 

What do you enjoy doing outside of the lab?  

Here at UCLA, we have one of the best programs in martial arts. I began taking classes when I was 50 after I was mugged and needed to learn how to defend myself. I earned my Black Belt in karate after 7 years. I also took classes in Muay Thai, which is boxing from Thailand that uses all your limbs. But my passion now is dancing the Argentine tango. This is one of the most beautiful dances in the world but also one of the most difficult. If you come to my lab, you will hear the tango. It also helps me with personal development because these dancers are professional high achievers. You must be very elegant; you must learn the steps; you must maintain your posture. Sometimes I get new ideas for my research while I’m dancing. I do what I can to come back fresh every day to the same room I’ve been coming to for 30 years. I am fortunate: I enjoy my life, my job, and my work, and I still love what I do. I’ve found ways to release all my stress in healthy ways. 

What message do you live by? 

Bruce Lee, the martial artist said, “Absorb what is useful. Reject what is useless. Add what is essentially your own.” And it applies to a science career. You will have bad experiences and good experiences. Always keep the best for you. Learn from your mistakes and the mistakes of others. 30 years in, coming from Mexico, and already old, I am surviving this environment. Competition is hard, but it’s the same for everybody. Having mentors helped me. And now I have students who are so smart, with MD-PhDs, and I try to learn from them. I think that my best advantages exist because almost everyone that I asked for help has provided it. 

Figure 1: Synaptic ribbon identification (green) in vestibular sensory hair cells located in the human utricle (balance organ) and nerve terminals (magenta). Laser confocal image generated with a Leica Stellaris microscope (Lopez Laboratory at UCLA).