Effects of psoriatic scale extracts on oxidative metabolic responses in granulocytes assessed by chemiluminescence.
The peptide fractions containing C5a des arg and anionic neutrophil activating peptide (ANAP) and the low-molecular-weight fractions containing LTB4 in psoriatic scale extracts exert a potent polymorphonuclear leukocyte (PMN) chemotactic activity. To evaluate whether any of these components in the psoriatic scale extracts stimulate a respiratory burst in PMNs, we studied luminol-dependent chemiluminescence (CL) in PMNs under their direct stimulation. After fractionation by molecular sieve chromatography, pooled peptide fractions eluting near the cytochrome c marker from eight samples induced high CL in PMNs, whereas those eluted in low-molecular-weight fractions after vitamin B12 marker were very weak in this response. Moreover, in six samples such low-molecular-weight fractions eluting near the vitamin B12 marker were found to have a suppressive effect on the oxidative metabolism of neutrophils induced by other stimulators. These findings suggest that the fraction of chemotactic peptides in psoriatic scales plays a major role in the activation of PMNs, inducing tissue damage in the psoriatic lesional epidermis. On the other hand, at least some low-molecular-weight components in psoriatic scales seem to exert an inhibitory effect on the respiratory burst induced by other activators.
Kato
T
T
Department of Dermatology, Tohoku University School of Medicine, Sendai, Japan.
Terui
T
T
Takematsu
H
H
Tagami
H
H
D002630:Chemotactic Factors / Q000302:isolation & purification* / Q000494:pharmacology; D004817:Epidermis / Q000378:metabolism; D005609:Free Radicals; D006098:Granulocytes / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008163:Luminescent Measurements; D008970:Molecular Weight; D010100:Oxygen / Q000378:metabolism; D011565:Psoriasis / Q000378:metabolism*
D002630:Chemotactic Factors; D005609:Free Radicals; D010100:Oxygen