Bacteria and viruses have ways to avoid these defenses, however. Yersinia pestis, the bacteria that causes bubonic and pneumonic plague, for example, can hide from the immune system, allowing it to replicate in the body unhindered until it can overwhelm the host. This ability allowed Y. pestis to spread bubonic plague across Europe in the 14^th Century, killing a third of the European population.

While plague may not be a serious threat to human health in modern times, researchers at the University of Louisville are studying Y. pestis to better understand its ability to evade the immune system and apply that understanding to control other pathogens.

“If you look at human plague, people don’t show symptoms right away even though they have an active infection because the bacteria is hiding from the immune system. Then all of a sudden there is a lot of bacteria, the immune system is overwhelmed and in the case of pneumonic plague, the individual dies from pneumonia,” said , professor in the UofL Department of Microbiology and Immunology.

Neutrophils are the immune system’s first responders, sending out protein molecules to summon other neutrophils to attack and destroy the invader. Among the first molecules sent out by neutrophils to signal an infection are Leukotriene B4 (LTB4) lipid molecules. Y. pestis interferes with the immune response by suppressing the LTB4 signals. Lawrenz has received a new $2.9 million, four-year grant from the National Institutes of Health to investigate how Y. pestis blocks LTB4. Ultimately, he expects this understanding will lead to ways to prevent Y. pestis from blocking the signals and hopefully, apply that understanding to other types of infections.

“This historic pathogen is really good at manipulating the immune system, so we use it as a tool to better understand how white blood cells like neutrophils and macrophages respond to bacterial infection,” Lawrenz said. “In this project, we are using Yersinia to better understand why LTB4 is so important to controlling plague. This understanding would apply to almost any infection of the lungs or other areas, and it probably could apply to viruses also.”

A member of the , Lawrenz has been studying plague bacteria for nearly two decades. His previous work includes discoveries of how Y. pestis acquires iron and zinc to overcome a host’s defense mechanism known as nutritional immunity and has increased understanding of how Y. pestis to hide from the immune system.

Katelyn Sheneman, a doctoral student in Lawrenz’s lab, also has received a prestigious $100,000 research award for trainees from the NIH. This grant will fund her research to understand how Y. pestis changes the contents of extracellular vesicles, cellular containers produced by immune cells that contain proteins, lipids such as LTB4 and other components. These vesicles are released into the bloodstream to communicate to other cells what is happening in their part of the body, such as an infection.

“My project is looking at how Y. pestis alters the number of vesicles being produced, what is being packaged in them and how other cells are responding to them,” Sheneman said. “We have some good evidence that pestis is able to manipulate the production of these vesicles, so we are going to look at the role the vesicles play in pulmonary infection and how that influence contributes to overall systemic infection.”

Since there is no effective vaccine against infection by Y. pestis and it has the potential to be used as a bioweapon, Lawrenz and Sheneman study Y. pestis in UofL’s Biosafety Level 3 facilities at the Regional Biocontainment Laboratory, part of a network of 12 regional and 2 national biocontainment laboratories for studying infectious agents. Biosafety Level 3 facilities are built to exacting federal safety and security standards in order to protect researchers and the public from exposure to the pathogens being investigated. 

Interim President Lori Gonzalez provided senators with current student enrollment and retention figures. A decline in undergraduate enrollment compared to last year was reported. Gonzalez said that administration anticipated this decrease and despite the current dip in student enrollment, current figures for the fall 2022 term show promise. Figures for the fall 2022 semester include a 6% increase in student applications, 14% increase in admissions and 30% increase in deposits.

Gonzalez further reported an increase in student retention rate of 91% from the fall 2021 to spring 2022 semester, improving upon the 86% student retention rate reported the previous year.

“Our fall to spring retention for first-year students is back to pre-pandemic levels, which is pretty amazing,” Gonzalez said. “Getting back in class and having the right kind of experience, I think, has made a big difference.”

Dan Durbin, executive vice president for finance and administration, and Keith Sherman, executive director and chief operating officer of the , presented information on the university budget and available funding currently offered through the foundation. Durbin provided an overview of the university’s $1.3 billion budget for fiscal year 2022. General or unrestricted funds are used to cover the unrestricted operating expenses incurred by the university; this funding accounts for about 40% of the institution’s total budget.

“Our unrestricted funding is made up of tuition, fees and state appropriations. Tuition and fees are influenced by external and internal factors, so we have very limited latitude when it comes to increasing unrestricted operating funds from tuition and fees,” Durbin said. “Our state appropriation is about $130 million a year; $127 million of that is base, and we have to earn the other $3 million through the Performance Funding model, so that $3 million is always at risk.”

Performance funding is reallocated each year based on each university’s performance relative to other institutions in the state. UofL performed better than the sector average in seven of the 11 performance metrics used to determine state performance funding. Despite a slight increase in 2022, state funding for the university has generally declined over the past decade.

The university’s general fund budget will soon face several significant challenges, including inflation, employee compensation increases and the 2025 demographic cliff projected to impact higher education enrollment and institutional aide nationwide. As neither state allocation nor tuition increases can meet these financial obstacles fully, units have been encouraged to take advantage of the $82 million that is currently available through the University of Louisville Foundation.

Sherman reported the total foundation funding, which includes both endowment and current use funds, is available to each UofL school and college. Senators were also provided with a recommended order of spending for all funding, both restricted and nonrestricted, to reduce general fund spending and maximize UofL’s budgetary efficiency.

“Grant monies typically need to be returned to the grantor if you don’t spend them, so you should spend those funds first. Then go to your restricted endowments and your restricted non-endowed gifts [before spending] your unrestricted money. Your unrestricted money is gold because you can do anything you want with it. We recommend spending unrestricted gifts before your unrestricted endowments because non-endowed gifts don’t grow.” said Sherman.

Committee reports and a of the meeting can be accessed on the . The next Faculty Senate meeting is scheduled for Feb. 8 and will take place remotely via Microsoft Teams.