ACTIVATION OF HUMAN NEUTROPHILS BY PHORBOL ESTER DECREASES THE CYTOPLASM COMPACTNESS AND THE LACTOFERRIN CONTENT OF THE GRANULOCYTES

• Type: Article in International Scientific Journal
• Date: 1991

Authors

ESAGUY, N (Author) Other; AGUAS, AP (Author) ICBAS; VILANOVA, M (Author) ICBAS; SILVA, MT (Author) Other

Journal

Title: Journal of Leukocyte Biology

Vol. 50 No. 5

Pages: 444-452

ISSN: 0741-5400

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 20 Citations

Scopus - 20 Citations

Scientific classification

FOS: Medical and Health sciences > Clinical medicine

Other information

Authenticus ID: P-001-QC3

Abstract (EN): Human neutrophils isolated from the blood were incubated in vitro for 30 min with 25 ng/ml of phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, to study its effect on the fine structure of granulocytes and on the subcellular distribution of lactoferrin (Lf). Flow cytometry analysis of the human neutrophils showed that PMA induced a decrease in size and granularity of the cells. By electron microscopy, the PMA-treated cells showed numerous empty vesicles, smoothing of the cell surface, and a marked decrease in the compactness of the cytoplasmic ground substance. High-resolution immunogold ultracytochemistry showed that neutrophils lost most of their content in Lf after the PMA incubation. In thin sections, the cytoplasmic compartment of PMA-treated neutrophils contained an average of 1.03 +/- 0.3 Lf-positive vesicles per-mu-m2, whereas control granulocytes showed an average of 5.72 +/- 1.49 Lf vesicles per-mu-m2 of cytoplasm. Most of PMA-treated neutrophils kept some Lf-positive vesicles; a significant minority (10-15%) of the granulocytes showed cytological features of cell death. We conclude that the PMA-induced neutrophil activation is associated with microanatomical changes that include i) exocytosis of most, but not all, of the Lf-bearing vesicles; ii) rounding up of the cell outline; and iii) decrease in the compactness of the cytoplasmic ground substance.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9