Site Search     
Dendritic Cell Based Cancer Vaccines
Genes of Health: Signature of Health and Disease in Humans
Human Dendritic Cell Biology
Humouse: An In Vivo Model of the Human Immune System
Infectious Diseases
Understanding of Systemic Lupus Erythematosus
Current BIIR Grants
Key BIIR Papers


Baylor Institute for Immunology Research
3434 Live Oak St.
Dallas, Texas 75204

Tel: (214) 820-7451
Fax: (214) 820-4813
Human Dendritic Cell Biology
Investigators: A. Karolina Palucka, John Connolly and Jacques Banchereau

A major focus of BIIR is the study of human dendritic cells. While B and T lymphocytes are the mediators of immunity, their function is under the control of dendritic cells. Dendritic cells in the periphery capture and process antigens, express lymphocyte co-stimulatory molecules, migrate to lymphocyte organs and secrete cytokines to initiate immune responses. They not only activate lymphocytes, they also tolerize T cells to antigens that are innate to the body (self-antigens), thereby minimizing autoimmune reactions. Once a neglected cell type, dendritic cells can now be readily obtained in sufficient quantities to allow molecular and cell biological analysis. With knowledge comes the realization that these cells are a powerful tool for manipulating the immune system. Several lines of research are pursued, which are based on the concept that dendritic cells include several subsets with distinct functions. Thus, two major differentiation pathways have been identified: the myeloid DCs and the plasmacytoid DCs.

The myeloid DCs are thought to derive from monocytes, a major cell type in the blood. BIIR scientists are pursuing the hypothesis that distinct subsets of myeloid DCs exist, each of which driving a distinct type of immune response. These distinct subsets of myeloid DCs are, according to BIIR scientist hypothesis, derived from monocytes in response to different cytokines which secretion may be triggered by different microbes.

Plasmacytoid DCs represent another important type of DCs. They are remarkable through their ability to secrete copious amounts of type I Interferon. BIIR scientists have revealed their fundamental role in the reactivation of memory immune responses. In particular, they contribute to the eradication of viral infection through the stimulation of specific humoral and cytotoxic immune responses.

The study of human dendritic cell biology is the fundamental program of BIIR that provides the basis for many other programs including:

 
Dendritic cells as cancer vaccines
The role of dendritic cells in autoimmunity
The Humouse: an in vivo model of the human immune system
 

The myeloid DCs are thought to derive from monocytes, a major cell type in the blood. BIIR scientists are pursuing the hypothesis that distinct subsets of myeloid DCs exist, each of which driving a distinct type of immune response.