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South Texas Center for Emerging Infectious Diseases

Floyd Wormley, Ph.D.

Assistant Professor of Microbiology & Immunology
Department of Biology
Office Phone: 210-458-7020
Lab Phone/fax: 210-458-7021


The research in our laboratory utilizes the human fungal pathogen Cryptococcus neoformans asCryptococcus neoformans a model organism to study host-fungal interactions for the purpose of developing novel immune therapies and/or vaccines to treat or prevent invasive fungal infections. C. neoformans, the causative agent of cryptococcosis, is an opportunistic fungal pathogen that has the propensity to cause respiratory tract infections in severely immune compromised individuals and possesses a unique predilection to invade the central nervous system causing life-threatening meningoencephalitis.

We focus our research in three main areas:

  1. To define protective host immune responses against C. neoformans infections.

    Our laboratory has developed a genetically modified strain of C. neoformans in order to study protective immunity to cryptococcosis. This strain, designated H99γ, is engineered to secrete murine interferon-γ. Mouse models of infection with H99γ demonstrate sterilizing immunity against subsequent infections with the highly virulent wild type strain H99. Ongoing projects in the lab utilize this strain to investigate protective host immunity to cryptococcosis, proteomically identify immunodominant C. neoformans proteins, and evaluate potential vaccine strategies utilizing genetically modified strains of C. neoformans.

  2. To identify targets for anti-fungal drug development.

    We utilize high throughput screening techniques to identify potential fungicides and inhibitors of fungal biofilm development in a small molecule library composed of natural and synthetic bioactive chemicals.

  3. To characterize C. neoformans biofilm-forming conditions.

    We are interested in characterizing conditions favorable to biofilm formation in vitro and to investigate the role of in vivo biofilms during C. neoformans infection.

    Our laboratory uses a variety of immunological and molecular biology techniques together with animal model systems to accomplish our research goals. The ultimate hope is that these studies will lead to a greater understanding of host-fungal interactions and the development of protective immune based therapies against invasive fungal infections.


  • S. Hardison, S. Ravi, M. Young, K. Wozniak, F. L. Wormley Jr., (2010). Induction of classical macrophage activation during experimental pulmonary cryptococcosis. American Journal of Pathology. 176(2).
  • K. Wozniak, S. Macias, S. Ravi, M. Young, C. Steele, and F. L. Wormley Jr., (2009). Insights into the mechanisms of protective immunity against Cryptococcus neoformans infection using a mouse model of pulmonary cryptococcosis. PLOS One. 4(9): e6854.
  • M. Young, S. Macias, D. Thomas, F. L. Wormley, Jr. (2009). A proteomic-based approach for the identification of immunodominant Cryptococcus neoformans proteins. Proteomics. 9(9):2578-88.
  • S. Ravi, C. Pierce, C. Witt, and F. L. Wormley Jr. (2009). Biofilm formation by Cryptococcus neoformans under distinct environmental conditions. Mycopathologia. (6): 307-14.
  • Pierce, C.G., P. Uppuluri, A.R. Tristan, F. L. Wormley Jr., E. Mowat, G. Ramage, J.L. López-Ribot. (2008). A simple and reproducible 96 well plate-based method for the formation of fungal biofilms and its application to antifungal susceptibility testing. Nature Protocols. 3:1494-1500.
  • K. Wozniak and S. Levitz. (2008) Cryptococcus neoformans enters the endolysosomal pathway of dendritic cells and is killed by lysosomal components. Infect Immun. Oct; 76(10):4764-71.
  • F.L. Wormley, Jr., J. R. Perfect, C. Steele, and G.M. Cox. (2007) Protection against cryptococcosis using a murine Interferon-gamma-producing Cryptococcus neoformans strain. Infection and Immunity. 75(3): 1453-62.


Dr. Karen L. Wozniak, PhD

Dr. Karen Wozniak

I am a Research Assistant Professor, and am interested in the innate immune response of dendritic cells (DCs) to Cryptococcus neoformans. DCs are cells of the innate immune system that act as sentinels and are critical for protection against C. neoformans infections. DCs recognize C. neoformans upon infection in the lung, internalize it, and then activate T cells, thus initiating the protective immune response. Following ingestion by DCs, C. neoformans moves rapidly into intracellular compartments called lysosomes, where killing and degradation occur. I am currently examining the mechanisms of cryptococcal killing by components of the DC lysosome.

SEM of C. neoformans phagocytosis by DCs

(Wozniak et al, Infection & Immunity 2008)
SEM of C. neoformans phagocytosis by DCs

TEM of intracellular C. neoformans in DCs

(Wozniak et al, Infection & Immunity 2008)
TEM of intracellular C. neoformans in DCs

Killing of C. neoformans by DC lysosome extract

Wozniak et al, Infection & Immunity 2008)
Killing of C. neoformans by DC lysosome extract


Mattie L. Young, Research Assistant

Mattie L. Young

I am a Research Assistant that has been with the Wormley Lab since 2007. My project focuses on the proteomic identification of immunodominant C. neoformans proteins. I use 2D gel electrophoresis and Western blotting to identify C. neoformans proteins that react to antiserum from mice immunized against C. neoformans. I hope to use these proteins as potential adjuvants and/or vaccines against cryptococcosis.

electrophoresis blots

(Young et al, Proteomics 2009)
2D electrophoresis blots demonstrating proteins that react to antiserum from immunized mice.


Sarah Hardison, Graduate Student

Sarah Hardison

I am a second year PhD student in the Cell and Molecular Biology Program at UTSA. My current project investigates the role of innate immunity in protection against C. neoformans infections, specifically looking at the activity of macrophages. Macrophages are phagocytic cells that, when activated, are responsible for the uptake and dissolution of C. neoformans cells during infection. I use immunohistochemistry and real time PCR techniques to determine the differential phenotypes of macrophages that respond during protective and non-protective cryptococcosis.

Immunohistochemical staining of pulmonary macrophages

Immunohistochemical staining of pulmonary macrophages
In green, alternative macrophage marker CD206. In blue, cell nuclei.


Gina Herrera, MARC-U*STAR Undergraduate Student

Gina Herrera, MARC U STAR Undergrad Student

I am an undergraduate pursuing my BS degree in Biology. I have been a part of the Wormley Lab since summer 2009 and am a member of the in the MARC U*STAR program. Since working in the lab I have learned several techniques in molecular biology and have presented data at both local and national conferences. I am currently working to create a mutant strain of C. neoformans that is deficient in an important virulence factor.