Joshua Mayoral

Mayoral Welcome 230

Mucin expression in intestinal epithelial cells infected with Toxoplasma gondii

Greetings, and welcome to my URM page!


I am currently a junior at NAU working in Dr. Fernando Monroy’s laboratory and majoring in biomedical science.

I plan on pursuing an M.D/Ph.D or D.O/Ph.D degree by attending medical school after obtaining my undergraduate degree at NAU. I would say my preferred interest in any scientific field is Immunology. Perhaps someday I can devote more time to my scheme of creating a personified, cutting edge video game involving Immunology…although Dr. Monroy would probably disagree. 

About my research

I am currently investigating the role mucin proteins play during infection with the parasite Toxoplasma gondii.

Read more

A future project will involve investigating the relationship between Toll-Like Receptor (TLR) activation and subsequent mucin expression.  Below is a brief abstract of my current research:

Intestinal epithelial cells are among the first cells in the gastrointestinal tract exposed to numerous microorganisms. These cells are not without defense, being shielded from the external environment by varying layers of mucus fundamentally composed of mucin proteins. The ubiquitous parasite Toxoplasma gondii is known to infect intestinal cells during the initial interaction with a host. However, the role of mucin proteins during infection with this parasite has not been previously investigated. To determine mucin gene expression during infection, RNA was extracted from both human and mouse intestinal epithelial cells and analyzed using PCR methodology. Results have demonstrated increases in several mucin genes in mouse intestinal epithelial cells, but no significant changes in several mucin genes in human cells. These results suggest differentiated immune responses by these two species, and a further understanding of these immune responses may lead to potential preventative therapies against a highly successful parasite.

Mayoral Research 1 470

Above is the life cycle of the parasite T. gondii, which utilizes a complex life cycle in order to ensure survival. A typical host for this parasite is the mouse, which I am currently studying by investigating mouse intestinal cells during infection.

The mucosal barrier and pathogen invasion

Mayoral Research 2 470

(Linden et. al., 2008)

Mayoral Research 3 470

Pictured above are examples of pathogenic invasion of the mucosal barrier and normal mucosal homeostasis. Pathogens exhibit a wide variety of strategies to penetrate the mucus in an effort to colonize the epithelial cell layer. Who knows what sort of strategies T. gondii implements, if any?

Since I am impatient in thinking of my future work (not that I loathe my current project), below are several images of Toll-Like Receptors; key immune structures which recognize foreign microbial signatures:

Mayoral Research 4 470
(Left: TLR1/TLR2 Complex, which recognizes various bacterial and fungal structures. Right: TLR3, which recognizes single-stranded RNA internally within a cell.)

About myself

I grew up in Murrieta, California until the age of 12, where I lived out a typical carefree childhood. Back in these days, my main hobby was video games. This hobby slowly faded; unfortunately, as time progressed, there didn’t seem to be enough time to enjoy a spiky-haired blue hedgehog racing through various metropolises. In 2005, my family moved to Ash Fork, Arizona; a small town about 50 miles west of Flagstaff. Had we not moved to such a rural town, I’d imagine my hobbies being much different. Experiencing the countryside, taking care of farm animals (including the extensive care of goats), and living on a 40-acre ranch certainly changed my lifestyle, most probably for the better.  Since childhood, I’d say I had a heavy interest in medicine; a career as a doctor seemed the most direct way of helping people, and I was mainly inspired by the care my mother and grandmother would provide whenever I was sick. Eventually, I convinced myself to pursue a career in medicine, and attended Northern Arizona University in the fall of 2010. I began undergraduate research in the fall of 2011 under the mentorship of Dr. Fernando Monroy through the URM program.

These days my hobbies include chess, soccer (F.C. Barcelona …and maybe F.C. Liverpool being my favorite teams), and listening to the scientific podcasts TWIVTWIP, and TWIM.

I would like to send a special thank you to my family, who continue to show their support despite my moody nature (!). I thank my research mentor, Dr. Monroy, who accepted me into his laboratory and continues to facilitate my research experience. I thank the URM program, for giving me the opportunity to obtain a better sense of research and its responsibilities. Lastly, I would like to thank all of my friends who have shaped me into who I am today.

Links to my research mentor’s, Dr. Fernando Monroy, homepage.

View other URM stories.