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Chemotaxis of polymorphonuclear neutrophils (PMN) in patients suffering from recurrent infection
H Brenneis1, A Schmidt, P Blaas-Mautner
1Institut für Immunologie, Universität Heidelberg, Germany.
Abstract:
PMN function was tested in patients suffering from recurrent infections. In 65 out of 240 patients lack of oxygen radical production or reduced chemotactic activity was found. In most cases the reduction was transient and associated with clinical impairments of the patients. Only a few patients had primary cellular defects. In one of those patients the expression of beta 2 integrins was reduced, while PMN of the other patients expressed beta 2 integrins normally. Thus, cellular defects other than the reduced expression of beta 2 integrins might also result in impaired chemotactic activity.
Insights
Recurrent infections in patients were linked to impaired neutrophil (PMN) function, specifically reduced oxygen radical production or chemotaxis. While often transient, a few cases revealed primary cellular defects beyond beta-2 integrin expression.
Area of Science:
- Immunology
- Clinical Medicine
- Cell Biology
Background:
- Recurrent infections can indicate underlying immune system deficiencies.
- Neutrophil (PMN) function is critical for combating bacterial and fungal infections.
- Impaired PMN function, including chemotaxis and oxidative burst, compromises host defense.
Purpose of the Study:
- To investigate neutrophil (PMN) function in patients experiencing recurrent infections.
- To identify the prevalence and nature of PMN functional defects in this patient cohort.
- To explore potential cellular defects contributing to impaired PMN chemotaxis.
Main Methods:
- Functional assays were performed on neutrophils isolated from patients with recurrent infections.
- Tests included assessment of oxygen radical production and chemotactic activity.
- Flow cytometry was used to evaluate beta-2 integrin expression in a subset of patients.
Main Results:
- Out of 240 patients, 65 exhibited either lack of oxygen radical production or reduced chemotactic activity.
- These functional impairments were predominantly transient and correlated with clinical symptoms.
- A small number of patients presented with primary cellular defects; one showed reduced beta-2 integrin expression, while others had normal expression despite chemotactic issues.
Conclusions:
- Transient neutrophil dysfunction is a common finding in patients with recurrent infections.
- Primary cellular defects, not solely related to beta-2 integrin expression, can cause impaired neutrophil chemotaxis.
- Further investigation into diverse cellular mechanisms underlying neutrophil dysfunction is warranted.