No, I never worked with him. Physically different building, different department.

Mila Pollock: Ah, so you did physically different– You were apart all the time.

Yes. Different building, different level. I was always at the neurosurgery and he worked in medicine.

Mila Pollock: You still worked in neurosurgery.

Physically, he also worked because he preferred the dendritic cells. I did the RNA. Usually, I did the transfection, analyzed the data. Sometimes he did the ELISA and we looked at the results together. He's a very quiet person. When we looked at the data, we cut each other's words because [gestures].

Which was, how should we do, what would be the next experiment to do? We were very excited.

Mila Pollock: You published in 2005, right? All the data that you received was in 2004?

Between 2002 and 2004. We submitted January 2005 actually the paper. We did all of this experiment between 2002 and 2004.

Mila Pollock: It's a major breakthrough and nobody– Did you submit first to big scientific journals, or not?

It was Nature what we submitted and immediately they sent it back. They didn't send out. It was just said that it is incremental. My English is not that good. I did not know that word, so I translated it into– "Incremental." I said, "No, no. It isn't." [chuckles] We immediately could see that there were two or three receptors, so that still was activated. Then we set it up with detecting double-stranded RNA, so we knew that next responsibility is to purify it. Then we did a lot of time how to purify. I remember New Year's Eve– New Year's Day. I was in the lab because I came to an idea that how we could get rid of the double-stranded RNA. It didn't work. We didn't use that, but that's what–

I went there because I wanted to be there. Because I had this urge, I felt that, "Okay, that's it." Also, we worked with Drew to try to show in animals that also– so we injected to animals and we could see that TNFR4 was not in use, then we did more experiments. The purification, eventually, we did HPLC purification and then we could see a tremendous increase of translation. Nobody cared and we just keep doing, improving. More protein was made from the RNA. Drew is a very preserving guy, but he told me that the telephone will ring in 2005– next day, finally, Immunity published, which is a very good journal. Not next day, not next month, not next year. 2005, up until 2010, nobody cared.

Up until a paper came out from Harvard showing that when they generated induced pluripotent cells, they needed pseudouridine-containing RNA. They referenced our paper and people say, "Oh, what is this all about?"

Mila Pollock: Oh, and where is it? What journal was it published here?

Our paper was in Immunity.

Mila Pollock: Immunity, yes. In 2005.

2005, Immunity. Then the next one, when we demonstrated that it was so small amount is sufficient and so on, and it was in vivo, is still working. All of these studies, we submitted in Nature Biotechnology, but it was not accepted. Actually, I met the person and apologized for that. They immediately sent it back and then it was published in Molecular Therapy. In these days, I don't think that it is so critical because people are going for the-

-topics or something, and then if they want, they can read online.

Yes. In these days, I don't think it is very critical to publish in the top-tier journal because people are looking at the top and then they find something following and they will read in another second-tier paper journals.

Dr. Katalin Kariko is a biochemist and adjunct professor of neurosurgery at the University of Pennsylvania. She won the 2023 Nobel Prize in Physiology or Medicine for her work in developing mRNA vaccines against COVID-19. She completed her schooling at the University of Szeged and carried out her post-doctoral work at the Institute of Biochemistry, Biological Research Centre of Hungary.

Dr. Kariko received her Bachelor of Sciences in Biology in 1978 and her PhD in Biochemistry in 1982 from the University of Szeged. She completed her post-doctoral work at the Institute of Biochemistry, Biological Research Centre of Hungary until 1985, when her lab at the Biological Research Centre lost funding. She then moved to the United States and carried out post-doctoral work at Temple University from 1981 to 1988 and at the Uniformed Services University of the Health Sciences from 1988 to 1989. She then joined the faculty of the University of Pennsylvania in the Perelman School of Medicine’s neurosurgery department in 1989.

At the University of Pennsylvania, she began to collaborate with immunologist Drew Weissman, where the two experimented with modifying mRNA. In the early 2000’s, Kariko and Weissman discovered that swapping uridine with pseudouridine in mRNA created a molecule with favorable attributes such as reduced adverse reactions. This breakthrough led the way for many other modified mRNA molecules to be potentially used in a multitude of future medical applications, including developing effective mRNA vaccines against the COVID-19 virus during the height of the pandemic in 2020. For their development of mRNA biotechnology, Dr. Kariko and Dr. Weissman were awarded the 2023 Nobel Prize in Physiology or Medicine.

Outside of the Nobel Prize, Dr. Kariko has received numerous awards for her contributions to science including the Lasker-DeBakey Clinical Medical Research Award in 2021, the Novo Nordisk Prize in 2022, being inducted into the National Inventors Hall of Fame in 2023, the Harvey Prize in Human Health in 2024, and elected to the National Academy of Sciences in 2025.