ISSN:
1573-2592
Keywords:
LFA-1
;
moderate phenotype
;
interferon-γ (IFN-γ)
;
tumor necrosis factor-α (TNF-α)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Leukocyte adhesion deficiency (LAD) is a recessive autosomal disease characterized by life-threatening recurrent bacterial infections, associated with defective functions of leukocytes due to deficient membrane expression of leukocyte adhesion glycoproteins. These proteins, LFA-1, Mac-1 (CR3), and p150,95 are α1β1 heterodimers composed of different α chains noncovalently associated with a common β chain. Patients with the severe phenotype of the disease completely lack the three glycoproteins on leukocyte surfaces, while patients with the moderate phenotype can express low levels of leukocyte adhesion proteins (1–10%). We have studied a patient with the moderate phenotype of LAD. Polymorphonuclear functions such as chemotaxis and adherence were altered, natural killer activity was low, and cytotoxic T-lymphocyte activity was abolished. Previous biochemical studies showed a conserved synthesis of both the LFA-1 α-chain precursor and the β-chain precursor with, occasionally, some amount of α-β complexes in the cytosol. β chain-specific mRNA transcripts of normal size were detected at normal levels in patients' cells. Attempts to increase the transcription of the β gene byin vitro treatment with TNF-α or IFN-γ were successful but did not result in increased membrane expression of the α-β complexes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00916815
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