Immune Response to HIV Infection

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Immune Response to HIV Infection

• June 28, 2001
• Ms. Jane Coyle-Morris
• Wyeth-Ayerst Research

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Immune Response to HIV Infection

• Immunology
• HIV Biology
• Immune Response to HIV Infection

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Role of Antibodies
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Antibody interaction with Complement Proteins
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Cytotoxic T-Cells
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Central Role of Helper T-Cells
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Macrophage
Large, irregularly-shaped phagocytic cells that
act as the bodys scavengers. Macrophages engulf
and consume foreign material such as bacteria and
viruses.
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T Cells
Arise from stem cells in the bone marrow then
migrate to the thymus gland where they develop
the ability to recognize foreign antigens in a
specific manner.
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Helper T Cells (TH)
Detect infection and initiate both humoral and
cell-mediated responses (CD4 cells)
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Cytotoxic T Cells (TC)
Recruited by TH to lyse infected body cells (CD8
cells)
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Cell Marker Proteins

• CD4 cell marker found on the surface of TH and
  macrophages acts as a receptor for HIV
• CD8 cell marker found on the surface of TC

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B Cells and Plasma Cells

• B Cells precursors of plasma cells, specialized
  to recognize particular foreign antigens
• Plasma Cells derived from B cells, they produce
  antibodies to specific antigens marking them for
  destruction

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Major Histocompatibility Complex (MHC)

• Proteins markers found on the surface of the
  bodys cells to signal self from non-self.
  MHC-I can be found on every cell in the body
  while MHC-II is found only on B cells, T cells
  and macrophages.

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Cytokines

• Soluble proteins secreted by the cells of the
  immune system to signal activation and
  proliferation of the appropriate components of
  the immune response. IL-1 is released from
  macrophages and signals activation of T cells.
  Activated T cells produce IL-2 which signals
  proliferation of T cell clones and also helps B
  cells to start secreting antibodies.

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Cytokines
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The Immune Response
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Central Role of CD4 T Cell
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HIV Biology
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HIV in Action
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Natural Course of HIV Infection
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Overview
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Immune Response to HIV Infection

• Immunology humoral vs. cell-mediated
• HIV biology complex series of events leading to
  viral entry and course of infection evasion of
  immune system
• Immune response to HIV weak humoral response,
  strong cell-mediated response diminished over
  time by depletion of helper T-cells

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AIDS/HIV Internet Sites

• Www.ama-assn.org/special/hiv/hivhome.htm
• www.planetq.com/aidsvl/index.html
• www.thebody.com/cgi-bin/body.cgi
• www.cdc.gov/
• www.pbs.org/wgbh/nova/aids/
• www.roche-hiv.com/default.htm