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IgA-associated inhibition of polymorphonuclear leukocyte chemotaxis in neutrophilic dermatoses
Abstract:
The chemotactic activity of normal human polymorphonuclear leukocytes (PMNs) confronted with heat inactivated sera from patients with psoriasis as well as various chronic proliferative diseases was determined using modified Boyden chambers. By the addition of phorbol myristate acetate (PMA) at a concentration of 1 ng/ml the chemoattractant activities of the sera were greatly potentiated. However, the chemotactic migration of normal PMNs was strongly inhibited by sera from patients with long standing and wide spread psoriasis, pyoderma gangrenosum, severe acne conglobata, Sweet syndrome, and some patients with chronic arthritis following rheumatoid fever. In acute guttate psoriasis and atopic dermatitis increased migratory activities were seen. The inhibition of chemotaxis correlated with increased serum IgA levels as determined by radial immuno diffusion. Column chromatography (Sephacryl S-300) revealed serum fractions of strong inhibitory potency at a molecular weight near 200,000 Dalton. These inhibitory fractions were seen in patients with long standing neutrophil related diseases and could not be detected in normal control sera. It appears that inhibition of PMN chemotaxis is a secondary phenomenon and may play an autoregulatory role in PMN related inflammation.
Insights
Sera from patients with severe psoriasis and related inflammatory diseases can inhibit polymorphonuclear leukocyte (PMN) chemotaxis. This inhibition, linked to elevated IgA, may play a role in regulating neutrophil-related inflammation.
Area of Science:
- Immunology
- Dermatology
- Cell Biology
Background:
- Polymorphonuclear leukocytes (PMNs) are crucial for inflammatory responses.
- Chemotaxis, the directed movement of cells, is vital for PMN function.
- Dysregulated PMN activity is implicated in various inflammatory diseases.
Purpose of the Study:
- To investigate the chemotactic activity of normal human PMNs in response to sera from patients with psoriasis and other chronic proliferative diseases.
- To identify factors in patient sera that modulate PMN chemotaxis.
- To explore the potential role of PMN chemotaxis inhibition in inflammatory conditions.
Main Methods:
- Modified Boyden chambers were used to assess PMN chemotaxis.
- Sera from patients with various inflammatory conditions and healthy controls were tested.
- Phorbol myristate acetate (PMA) was used to potentiate chemoattractant activity.
- Radial immunodiffusion was employed to measure serum IgA levels.
- Column chromatography (Sephacryl S-300) was utilized to fractionate sera and identify inhibitory components.
Main Results:
- Sera from patients with long-standing, widespread psoriasis, pyoderma gangrenosum, acne conglobata, Sweet syndrome, and chronic arthritis inhibited normal PMN chemotaxis.
- Acute guttate psoriasis and atopic dermatitis sera showed increased PMN migratory activity.
- Inhibition of chemotaxis correlated with elevated serum IgA levels.
- Chromatography identified inhibitory serum fractions with a molecular weight near 200,000 Daltons, present in patients with chronic neutrophil-related diseases.
Conclusions:
- Serum factors, particularly those associated with elevated IgA, can significantly inhibit PMN chemotaxis in certain chronic inflammatory diseases.
- The identified inhibitory fractions may represent an autoregulatory mechanism in neutrophil-related inflammation.
- Understanding these inhibitory mechanisms could offer insights into managing inflammatory conditions.