Mnemonics: Human immunodeficiency virus (HIV)

Author: V. Dimov, M.D., Allergist/Immunologist and Assistant Professor at University of Chicago
Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at LSU (Shreveport) Department of Allergy and Immunology

- HIV (non-syncitia-inducing (NSI) strains) uses the chemokine receptor CCR5 to enter macrophages and monocytes.

Most common type of HIV
Monocytes
Macrophages

- HIV (syncitia-inducing (SI) strains) uses the chemokine receptor CXCR4 to enter CD4 T-cells.

CCR5
CXCR4 (CD4)

F
Five - CCR5
Four - CXCR4 (CD4) - also involved in WHIM syndrome (PIDD)
Foray of HIV into the CD4 T-cells

Evidence for the cure of HIV infection by CCR5 delta 32/delta 32 stem cell transplantation http://j.mp/gwDMH5 and http://j.mp/fQJAlM

A mutation of CXCR4 causes a phagocytic defect called WHIM syndrome (Warts, Hypogammaglobulinemia, Infection, and Myelokathexis). Myelokathexis refers to retention (kathexis) of neutrophils in the bone marrow (myelo). Myelokathexis causes severe chronic leukopenia and neutropenia.


(Click to enlarge the image).

CCL5 or RANTES - HIV-suppressive factor released from CD8+ T cells

F
Five - CCL5
Fights HIV


Chemokine structures. Image source: Wikipedia, GNU Free Documentation License.

CCR5 Mutation

Delta 32
Deletion
Delayed progression in single mutation

Stem cells from a donor who was homozygous for CCR5 delta32 were transplanted in a patient with acute myeloid leukemia and HIV-1 infection. The patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.


HIV Infection. This video describes how HIV infects the host. This video is from: Janeway's Immunobiology, 7th Edition, Murphy, Travers, & Walport. Source: Garland Science.

HIV can attach to dendritic cells through the binding of gp120 to the adhesion molecule DC-SIGN (dendritic cell-specific intercellular adhesion molecule-grabbing nonintegrin).

SNPs associated with atopic diseases

Filaggrin gene
Filaggrin is essential for epidermal barrier function. SNP associated with eczema and asthma.

17q12-21 gene
ORMDL3 protein defects associated with asthma.

5q22-32 gene
CD14 is a lipopolysaccharide (LPS) receptor. SNPs associated with asthma and atopy.

3p21-22 gene
CCR5 is a chemokine receptor. SNP can be protective against asthma.

Xp22 gene
TLR7 and TLR8 are recognition receptors for viral ssRNA. SNPs assciated with asthma, rhinitis, atopic dermatitis.

5q31 gene
IL-13 is a cytokine that induces IgE secretion, mucus production, and collagen synthesis (fibrosis). SNPs associated with asthma.

ADRB2 gene
ADRB2 gene encodes β2-adrenergic receptor. Argenteum (Arg) or Arg/Arg phenotype associated with decreased albuterol response compared to Gly/Gly phenotype at residue 16.

ADAM33 gene
Type 1 transmembrane protein involved in cell-to-cell interactions. SNPs associated with asthma.

References

Long-Term Control of HIV by CCR5 Delta32/Delta32 Stem-Cell Transplantation. NEJM, Volume 360:692-698 February 12, 2009 Number 7.

Published: 05/06/2009
Updated: 06/17/2010

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