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
Neutrophils and other phagocytes migrate to the site of infection, ingest pathogens, and destroy them after releasing granule contents and active oxygen. These activities are closely associated with a rapid reorganization of the cytoskeleton, in which actin polymerizes, cross-links, anchors to the membrane and depolymerizes under the control of various actin-associated proteins.
Defect in actin results in neutrophil cytoskeletal disease where abnormality primarily appears as motility or chemotactic defect of the cells.
The first case of neutrophil actin dysfunction (NAD) was reported in 1974, a male infant with a severe neutrophil motility disorder and poorly polymerizable actin in PMN extracts. NAD is associated with a true defect in PMN actin assembly and is a genetic disorder that is recessively inherited.
Which of the the following conditions is associated with impaired phagocytic uptake:
(A) neutrophil actin dysfunction
(B) cyclic neutropenia
(C) hyper-IgM syndrome
(E) IgA deficiency
(F) Kostmann' syndrome, severe congenital neutropenia (SCN)
Correct answer: A
Neutrophil actin dysfunction is a genetic disorder associated with partial impairment of neutrophil actin assembly in three family members. F S Southwick, G A Dabiri, and T P Stossel. J Clin Invest. 1988 November; 82(5): 1525–1531.
Neutrophil Cytoskeletal Disease. International Journal of Hematology, 2001.