Englert, Alexandra, authorPodell, Brendan K., advisorHenao-Tamayo, Marcela, committee memberMaristela, Lea, authorHunstad, Lauren, authorAckart, David F., authorLanni, Faye, author2025-05-092025-05-092025https://hdl.handle.net/10217/240590- Zip file contains: HTML data and poster. To view interactive HTML files displaying inflammation induration response data and HTML poster file, download the files to the computer and open them in a web browser.Alexandra Englert - Statement of Personal Involvement: For this project, I was responsible for performing the IFN-γ ELISpots to test for systemic inflammation in response to M. bovis using PBMCs. By completing these tests, I compared the IFN-γ production of strong and weak responders to the BCG vaccine as well as those mock-vaccinated with saline. Additionally, I completed the overall data analysis, which allowed me to draw conclusions about the efficacy (or lack thereof) of the BCG vaccine in guinea pigs. After drawing these conclusions, I completed a poster describing them and presented it at CSU's Undergraduate Research Symposium. Finally, I wrote a final paper delving into the trends found in the data and connected them to the aforementioned conclusions drawn.- BCG Response Induration Data: Interactive document displaying inflammatory induration at the BCG vaccination site. Completed by David F. Ackart.- PPD Response Induration Data: Interactive document displaying inflammatory induration at the skin test site. Completed by David F. Ackart.- Poster: Corresponding poster presented at CURC (Celebrate Undergraduate Research and Creativity Showcase) at CSU on April 17th, 2025. Completed by Alexandra Englert.- Honors thesis: Paper describing the outline, methods, and results of the experiment. Completed by Alexandra Englert.Guinea pigs, while having been used as a model animal for tuberculosis infections for over a century, modern literature about their response to the commonly used BCG vaccination is limited. In this study, we investigated whether immune responses to the BCG vaccine are variable and if these differences could predict protection after exposure to Mycobacterium tuberculosis. Using the guinea pig model, the only rodent species that reliably develops delayed-type hypersensitivity responses similar to humans, we evaluated inflammation in response to BCG vaccination, tuberculin skin test (TST) response, and capacity for antigen-specific secretion of IFN-γ by ELISpot in response to M. bovis purified protein derivative (PPD). We hypothesized that the degree of inflammation incited by BCG vaccination would correlate with TST size and frequency of antigen-specific IFN-γ production. Most of the animals developed an inflammatory response to TST within 24-72 hours, indicating a Th1 response was developed post-vaccination. However, 4 out of 18 individuals lacked an inflammatory response that lasted over 24 hours. To confirm this, IFN-γ production was assessed in PBMCs isolated from BCG-vaccinated and unvaccinated guinea pigs, finding little correspondence between IFN-γ production and increased skin inflammation. We hypothesized that IFN-γ secretion would be highest in guinea pigs with the largest TST response. The results of this study demonstrate the development of a delayed-type hypersensitivity response to BCG vaccination, albeit inconsistent in its systemic effects. Collectively, our results a highly differential response to BCG vaccination. If vaccination confers variable protection against M. tuberculosis infection, this variable vaccine response may offer insight into correlates of immune protection.born digitalStudent worksZIPHTML DATAHTML POSTERengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.guinea pigBCGtuberculosisimmunologyinterferon gammaELISpotM. tuberculosisM. bovisvaccinationvaccinetuberculin skin testTSTMycobacterium tuberculosisMycobacterium tuberculosis bovisMtbIFN-γIFNγIFN-yIFNyMicrobiologyMycobacteriaBCG vaccineText