helAssociate Professor of Pathology

Address: Shelby Bldg., r. 603
Birmingham, AL 35294
Telephone: (205) 975-7079
Email:  zhel@uab.edu

Members of the Laboratory




M.S., (Biochemistry), Suma cum Laude (Dean's list), Department of Biochemistry, School of Natural Sciences, Charles University, Prague, Czech Republic
Ph.D. (Experimental Medicine), Suma cum Laude, Center for the Study of Host Resistance, Research Institute of Montreal General Hospital, McGill University, Montreal, Canada
Postdoctoral Fellow, Laboratory of Animal Models and Retroviral Vaccines, National Cancer Institute, NIH, Bethesda, MD, USA

Research Interests

Research in our laboratory focuses on the following areas: 1) Pathogenesis of HIV-1 infection. The decline of CD4+ T cells, a hallmark of HIV-1 infection and indicator of disease progression, is caused primarily by chronic activation of immune system; however, the underlying causes of this activation remain unclear. We hypothesize that HIV-1 infection is associated with a severe reduction of IgA responses to common microbial and food antigens proportionally to the extent of CD4+ T cell depletion and polyclonal activation of IgA-producing B cells at mucosal tissues. We investigate whether the inability to mount specific IgA responses results in increased absorption of environmental antigens to the systemic compartment contributing to the chronic activation of CD4+ and CD8+ T cells characteristic for HIV-1 infection. 2) HIV-1 vaccine development. SIV infection in macaques closely resembles human AIDS and represents the best model for assessing the protective efficacy of candidate HIV-1 vaccine. Previously, we demonstrated that immunization with an attenuated recombinant poxvirus vector NYVAC-SIV in combination with a DNA-SIV vaccine candidate expressing the structural genes of SIV resulted in high levels of virus-specific CD4+ and CD8+ T-cell responses and in a significant suppression of viremia following an exposure to the highly pathogenic SIV virus. In addition, we showed a significant improvement following an addition of early/auxiliary genes rev, tat, and nef to the vaccine. Currently, we are developing and testing new vaccine strategies. 3) Design of novel strategies for immunotherapy of cancer. Immunization of patients with tumor-associated antigens results in the induction of tumor-specific immune responses that can significantly restrict or eliminate the spreading tumor. We are testing the possibility of transplantation with genetically modified hematopoietic stem cells (HSCs) targeting the expression of antigen to activated dendritic cells as a strategy for long-term cancer immunotherapy. In a second project, we investigate immunization with antigen-presenting genetically modified B cells specifically targeted to secondary lymphoid tissue.