Last time when I visited Korea, one of my sunbaes (college seniors) told me that even startups need practice (she is a CEO of Biotech CRO) and practice with any kind of business. I thought about what I could do. That was making books, since I already had personal notes. However, I did not know how to get ISBNs, how to calculate cover thicknesses, how to choose papers, or where to print and sell books.
In Korea, I used Indipub for distribution. Actually, I arranged for the printed book to be delivered directly to the Indipub’s office. In the US, I used Amazon KDP to publish a poem book, both as an eBook and in print. Printing price is cheaper in the US than in Korea, but the quality and variety are limited in the US.
This year, I tried creating children’s picture books using Pages and JPEG images by exporting as ePub. While I worked on them, I realized that JPEG (file size) is smaller than PNG, and iBooks does not support any more ePub previews, so I used Cradle instead of iBooks. I just published two books through Amazon KDP and Barnes & Noble. One book was by my first daughter, and the other by my second daughter. I hope to continue supporting other kids to publish their own books. Writing and publishing seem to help them grow and become more thoughtful about the world around them.
Furthermore, working together with my kids makes me happy and helps me learn more and allows me to better understand how the world works and how the world changes quickly. Today, I discovered how to make eBooks available for free. At Amazon KDP, authors can not offer their books for free all the time, but through KDP, we can make them free 5 days within a 90-day period.
When my most recent biotech workplace shut down, I found myself at a crossroads. I still had the energy to dream of building a biotech startup, but after watching two companies I worked for shut down, I couldn’t even convince myself it would succeed.
So, instead, I took a different path. I enrolled in a free nursing course, a CNA program near my home, because I wanted to learn how I could continue helping others. That choice took me back in time to 1997–1998, when I worked with my college seniors in the psychology therapy club Torch Band and visited juvenile detention centers and psychiatric hospitals. Later, in 2008, I also learned about sandplay therapy. Those memories resurfaced as I began my new journey in nursing. After receiving my CNA certification, I worked at a nearby memory center while also preparing for pre-nursing courses. Since my previous college studies hadn’t included all the required U.S. nursing prerequisites. For example, I had taken animal physiology but not human physiology, so I needed to fill such gaps. At the memory care where I worked for a while, I noticed that quite a few seniors struggling with memory loss also had glaucoma. I can’t say that’s scientifically proven. I just noticed that some studies failed to show significant statistics on the connection. Someday, if I have the time, I’d love to dig into Korea’s public medical insurance datasets and explore the common mechanisms behind these conditions in more detail. What made me truly happy was seeing positive changes in the seniors with memory problems I cared for.
Maybe my interest in nursing was also influenced by my first daughter. In high school, she joined a medical club, and before college, she even took part in a high school internship program at Scripps Hospital. Later, even after choosing computer science as her major at UC Davis, she pursued EMT training. But in the summer of 2025, both of us stepped away. I quit my role as a care manager, and she stopped EMT training. That early summer, she was struck by a virus and diagnosed with meningitis. For nearly a month, her life was at risk, and I stayed by her side, helping her fight to survive. It brought back memories of my own hospitalization, when I spent a month with a high fever and no diagnosis. I still remember that near-death moment. Even in that split second, the experience remains etched vividly in my mind.
Even now, I still want to learn more about clinical care, but at the age of 50, it feels too late, less enjoyable, and not quite aligned with my current situation. While taking some pre-nursing courses, I also began exploring computer-related courses online and still hope to keep learning new things. My dream of starting a biotech company inspired me to explore publishing ventures, try self-publishing, and eventually start a nonprofit with my younger daughter. She is actually the founder and guiding force behind the BunnyPals Foundation. BunnyPals started as a small club for kids who had bunnies, but now it has grown to include writing and craft clubs, as well as Korean language learning. I hope to help children nurture creativity, compassion, and environmental awareness through artistic expression, storytelling, and community engagement. I also dream of helping them become authors of their own creative works.
Part of me still dreams of returning to research or building a research-focused nonprofit or startup. I wait for that dream.
Looking back, my life has been a journey of choices. Some I treasure, some I wonder about. For example, I once had the chance to pursue medical school or clinical psychology, but I didn’t. Do I regret it a little? Yes. But deep down, I know that even if I could go back, I might still choose this same path.
As an undergraduate in Korea, I never knew clinicians could also be researchers. I simply wanted to discover something new and contribute to patients’ well-being as a scientist. Also, I know if I chose a different path, I would have never researched. Now, though, I believe that for most people, education and lifestyle changes should come before medication.
To my juniors, including my daughters, I hope you’ll always find the resources you need for your career paths and that you’ll follow not just ambition but also your heart. May you always be wise enough to find balance between life, work, and money.
I’ve always been fascinated by antibodies. My journey began in 2000, when I first took an undergraduate immunology class. During graduate school in Medical Biotechnology, I dove deeper—advanced immunology in 2001, psychoneuroimmunology in 2002—researching NKT cells and CD1d in autoimmune diseases. Back then, my curiosity was pure: I just wanted to understand how things worked. Papers, grants, and impact factors? I didn’t think about those. Honestly, even now, grant writing still feels like a mountain to climb!
Until 2018, during my third postdoc, I never actively pursued grants. I was fortunate to be in well-funded labs, free to follow my interests, attend meetings, and write papers when inspiration struck. That freedom was exhilarating. I often chose research topics my supervisors weren’t interested in—at least initially—giving me the joy of discovery.
But freedom has a cost. By the time I tried to apply for my own grant, it felt late. I wrote one in 2018, only to have my name removed by my PIs and replaced with a colleague’s. They told me it would increase our chances of funding. I also learned a hard lesson: in both academia and industry, even great data isn’t always shareable due to patents. At the end of the day, the only guaranteed rewards were a paycheck and the sheer pleasure of exploring science.
Sometimes I wonder if I should have pursued a Ph.D. in immunology instead of neurobiology. I missed a lot of immunology along the way. Still, I wouldn’t trade my journey—it shaped the scientist I am today.
Generating Antibodies: My Hands-On Experience
If you’ve worked in biology or medicine, you know antibodies are everywhere. They’re essential for research and diagnostics, from simple antibody staining to generating completely new reagents.
During my Ph.D., I generated antibodies both in-house and through companies. I provided expression constructs, sometimes purified proteins, and worked with animals like mice or ferrets. It took time, patience, and more than a few failed attempts—especially for antibodies against certain domains. For instance, when generating pan-antibodies against protocadherin 7, we eventually produced polyclonal antibodies, but monoclonal antibodies just didn’t cooperate.
Fast forward to 2020–2021: antibody engineering has advanced tremendously. I created numerous AAV constructs, including Fab and scFv, analyzing backbones, VH, VL, CDRs in detail. Companies sometimes tweaked CDRs sequences, either randomly or with AI. Even Fc regions required careful attention, as they could influence adverse effects in the case of Fc-fused proteins and full antibody drugs. To generate AAV constructs, all other parts, such as promoter regions, signal peptides, linkers, polyA, WPRE, etc., should be considered. The next steps are to check whether the antibody-based fragments are secreted and work properly by Western blots and ELISA. Of course, in the case of AAV constructs, we should check AAV property and yields and have AAV first.
Fc and Fab: The Power of Two
Antibodies have two main regions: Fab and Fc.
Fab or variable regions bind to antigens
Fc, often called the “effector arm or tail,” performs critical functions:
Cell-mediated and humoral immune activation: Fc binds Fc receptors on macrophages, neutrophils, NK cells, and dendritic cells and leads to ADCC (antibody-dependent cellular cytotoxicity) and ADCP (antibody-dependent cellular phagocytosis).
Complement system activation: Fc triggers pathogen lysis, opsonization, and inflammation.
Half-life regulation: Fc binds neonatal Fc receptor (FcRn) in endothelial cells, protecting antibodies from degradation.
Maternal-fetal transfer: IgG Fc interacts with FcRn in the placenta, passing immunity to the fetus.
When designing therapeutic antibodies, deciding whether to keep, engineer, or remove Fc is crucial. Fab fragments penetrate tissues better but have shorter half-lives. Fc is often necessary for cancer therapies, whereas autoimmune or blocking therapeutics benefit from Fc engineering to avoid harming self-tissues.
A Look at Therapeutic Antibodies
Here’s an overview of some major monoclonal antibody drugs and their Fc strategies:
Drug
Target
Indication
Fc Strategy
Engineering / Mutations
Rituximab
CD20
B-cell lymphoma, RA
Active Fc → ADCC + CDC
None
Trastuzumab
HER2
HER2+ breast & gastric cancer
Active Fc → ADCC
None
Adalimumab
TNF-α
RA, Crohn’s, psoriasis
Neutralizing
None
Cetuximab
EGFR
Colorectal & head/neck cancer
Active Fc → ADCC
None
Nivolumab
PD-1
Melanoma, NSCLC
Fc-silent → avoids killing T cells
IgG4 backbone + S228P
Pembrolizumab
PD-1
Similar
Fc-silent
IgG4 backbone + S228P
Omalizumab
IgE
Severe asthma, urticaria
Fc engineered to avoid mast cell activation
IgG1 backbone; avoids C1q binding
Bevacizumab
VEGF-A
Colorectal cancer, AMD
Neutralizing; Fc not critical
Wild-type IgG1
Key patterns:
Cancer drugs keep Fc active to kill tumor cells.
Checkpoint inhibitors silence Fc to avoid killing PD-1+ T cells.
Anti-cytokine drugs have no effector function, but increase half-life by FcRn recycling.
Anti-IgE drugs engineer Fc to prevent dangerous immune activation.
Fc-Free Antibodies: A Growing Field
Fc-free antibody fragments are also gaining attention. As of August 27, 2025:
Status
Count
%
FDA-approved
15
27%
Terminated / Withdrawn
10
18%
Under Clinical Development
26
47%
Regulatory review
4
7%
database for Therapeutic Antibodies (db.antibodysociety.org)
Even though Fc can trigger strong immune responses, careful control – through dosing or engineering – can make it highly beneficial. Fc-free fragments face challenges like short half-life or lack of effector function, explaining why some have been terminated.
Antibody research is a perfect blend of biology, engineering, and clinical innovation. It’s a field full of stories – both successes and failures – that teach us how to translate basic science into therapies.
I’ve recently started reading again a book on therapeutic antibody engineering (2012), and I plan to share insights and reflections here from time to time.
Today, I want to talk about Gojoseon, the first kingdom of Korea.
Records about Gojoseon are found in the book Samguk Yusa (written by Buddhist monk Iryeon), which says that it was founded in 2333 BCE by Dangun Wanggeom.
According to the Dangun myth, Hwanung (a heavenly being who descended to earth) had a son named Dangun with Ungnyeo (a bear who transformed into a woman). The country that Dangun established was called Joseon. Later in history, another kingdom called Joseon appeared, as you know, so historians use the name Gojoseon (“Old Joseon”) to refer to the earlier kingdom. Chinese historical texts such as the Shan Hai Jing and Guanzi also mention Joseon.
Gojoseon was based on a Bronze Age culture but broadly seems to cover the late Neolithic and early Iron Age and was said to have the Law of Eight Prohibitions. Among them, three laws are still passed down and known:
A person who commits murder shall be executed.
A person who injures another must compensate with grain.
A person who steals shall become a slave. To redeem themselves, they must pay a fine of 500,000 coins.
It is believed that Gojoseon’s territory may have reached as far south as present-day Seoul.
In Korea, many dolmens (ancient stone tombs, Goindol in the Korean pronunciation) can still be found throughout the Korean Peninsula.
If you want to see a representative example, you can visit LegoLand in Chuncheon, South Korea, where such remains as Neolithic pit houses and Goindols scattered. In fact, it is known that the land beneath LegoLand contained many archaeological things, and the construction of the park was heavily opposed. Despite this, LegoLand was eventually built on the site.
You can check it out on this website! But the information is written in Korean.
There is one Korean drama, Tae Wong Sa Shin Gi based on the Gojoseon legend.
Unfortunately, there are still no officially English-dubbed versions. JustWatch and Netflix only provide non-English versions.
Life and Biology stories with Sooyoung and Others 