University of Wisconsin
School of Medicine and Public Health

Caldera/Hayney Research

Freddy Caldera, DO, MS, and Mary S. Hayney, PharmD, MPH | Immune Response to Vaccines in Immunosuppressed Patients

Mary Haynay, PharmD, MPH
Freddy Caldera, DO, MS

Freddy Caldera, DO, MS, is a formally trained clinical investigator, gastroenterologist, and physician scientist who specializes in inflammatory bowel disease (IBD). Mary S. Hayney, PharmD, MPH, is a professor at the University of Wisconsin School of Pharmacy.

The major focus of the Caldera/Hayney lab is to evaluate the immune response to vaccines in patients with inflammatory bowel disease or who have undergone solid organ transplantation.

Dr. Caldera's Faculty Biography

Dr. Hayney's Faculty Biography

Dr. Mary Hayney pointing to lab item that researcher holds while Dr. Caldera observes

Evaluating Immune Response to Vaccines

In a randomized clinical trial, Drs. Caldera and Hayney found that the high-dose influenza vaccine induces higher antibodies compared to the standard dose influenza vaccine in immunosuppressed patients with IBD. Their results suggest patients with IBD may benefit from receiving a high-dose influenza vaccine.

During the COVID-19 pandemic, Drs. Caldera and Hayney launched HumoRal and CellULar initial and Sustained immunogenicity in patients with IBD (HERCULES), a prospective study that evaluatea the humoral and cellular immune response to COVID-19 vaccines in patients with IBD.

Their initial results have shown that most patients with IBD are able to mount a humoral immune response to the vaccine and that all participants who received three COVID-19 vaccines had a humoral immune response. They also found that the cellular immune response to the vaccines were not impacted by the immunosuppressive therapies used to treat IBD after the initial two doses. They will continue to evaluate different aspects of the immune response to COVID-19 vaccines.

photo of equipment in Caldera lab

Laboratory Capabilities

Located on the 4th floor of Rennebohm Hall, the Caldera/Hayney lab is is well-equipped for vaccine-induced immune response studies. It has biologic safety cabinets, centrifuges, ultracold freezers, plate readers, and other standard lab equipment. Routine assays for the lab include ELISA, ELISPOT, hemagglutination inhibition assay, cell culture, and microneutralization.

Active Projects


This clinical study looks at the immune response to COVID-19 vaccines in patients with inflammatory bowel disease (IBD). 

Patients with IBD are often treated with immunosuppressant drugs. Certain immunosuppressants, such as steroids, may increase the risk of a severe outcome from COVID-19. Studies have also shown that certain medications may blunt the immune response to certain vaccines. This study involves blood draws from patients to examine the immune system response after vaccination by evaluating antibodies and T cells.

Related news story

Immunogenicity of Herpes Zoster Subunit Vaccine in Inflammatory Bowel Disease Patients Treated With Vedolizumab

The purpose of this study is to determine the immunogenicity of the herpes zoster subunit vaccine in inflammatory bowel disease patients on vedolizumab compared to those on anti-tumor necrosis factor (TNF) monotherapy.

More details

Dr. Caldera talking to Dr. Hayney in the lab


View Dr. Freddy Caldera’s publications on NCBI My Bibliography

View Dr. Mary Hayney’s publications on NCBI My Bibliography

Funding Support

Dr. Caldera's research is funded by medical society and pharmaceutical industry grants.

Make a Gift

Help support our research by making a gift to the Department of Medicine's UW Liver and Digestive Disease Center Fund.