Biology Of The Novel C-type Lectin Receptor DCL-1 In Innate And Adaptive Immune Response
Funder
National Health and Medical Research Council
Funding Amount
$439,500.00
Summary
The innate immune system is the first line of defense in protecting the body from infection. Phagocytic (meaning eating) white blood cells, which include dendritic cells and macrophages are equipped with cell surface proteins These bind the many types of microbes that cause infection, allowing the phagocytes to destroy them (innate immune response). Furthermore, dendritic cells and macrophages have mechanisms to activate additional specific responses (adaptive immune response) mediated by lympho ....The innate immune system is the first line of defense in protecting the body from infection. Phagocytic (meaning eating) white blood cells, which include dendritic cells and macrophages are equipped with cell surface proteins These bind the many types of microbes that cause infection, allowing the phagocytes to destroy them (innate immune response). Furthermore, dendritic cells and macrophages have mechanisms to activate additional specific responses (adaptive immune response) mediated by lymphocytes (T and B cells). We have discovered a cell surface protein, termed DCL-1, which may play a role in uptake of microbes by phagocytes and activation of innate and adaptive immune responses. This project will examine the mechanisms whereby DCL-1 mediates these immune responses. Understanding the mechanism may allow us to exploit DCL-1 for tumor immunotherapy.Read moreRead less
Role Of Plasmacytoid Dendritic Cells And Neutrophils In The Generation Of Antiviral Immunity
Funder
National Health and Medical Research Council
Funding Amount
$469,500.00
Summary
Work described in this application is important in understanding how two very different types of white blood cells, namely neutrophils and plasmacytoid dendritic cells (PDC), contribute to the generation of an effective immune response and control of virus growth. Both these cell types are activated in the earliest phase of the host response and are likely to play crucial roles in determining the nature of the later components of the response. We have recently shown that animals depleted of Gr-1 ....Work described in this application is important in understanding how two very different types of white blood cells, namely neutrophils and plasmacytoid dendritic cells (PDC), contribute to the generation of an effective immune response and control of virus growth. Both these cell types are activated in the earliest phase of the host response and are likely to play crucial roles in determining the nature of the later components of the response. We have recently shown that animals depleted of Gr-1+ cells, with monoclonal antibody (mAb) RB6-8C5, rapidly succumb to a poxvirus infection (mousepox) with 100% mortality. In contrast, mice treated with a control mAb clear the infection very effectively. Host responses essential for recovery from mousepox, including antiviral cytotoxic T lymphocyte (CTL) response and gamma interferon production, are severely diminished in mice treated with the Gr-1+ cell depleting mAb. Since the mAb can potentially deplete both neutrophils and PDC, this raises the important question of whether one or both of these cell types may be involved in the generation of cytokine and cell-mediated immune responses to viral infection. Although PDC and neutrophils themselves are not thought to present antigen to T cells, the elucidation of how they may control the generation of this major arm of the immune response will be novel and has important implications for vaccine design. Virtually nothing is known about how neutrophils or PDC influence viral antigen presentation by antigen presenting cells. Several murine models of viral infection, that in many ways mimic the diseases in humans, will be used to map the sequence of events initiated by PDC and neutrophils and which end in the clearance of virus from the host. Understanding these pathways and identifying the essential mediators and their interactions is critical in elucidating the role of the two cell types in the host response to virus infection.Read moreRead less