Cytoplasmic granules of polymorphonuclear leukocytes (PMN) from blood resolve during velocity centrifugation into well separated bands I, II, and III (sedimentation increasing in that order). Band I comprises empty vesicles and 85% of the biochemically measured alkaline phosphatase of the whole PMN. Specific granules, which are peroxidase negative and contain 50% of the PMN lysozyme and 77% of the lactoferrin, constitute band II. Their average diameter is 0.13 μm. The azurophil granules, with average diameters of 0.3 μm constitute band III and contain 88% of the immunochemically measured myeloperoxidase, 84% of the neutral protease, and 46% of the lysozyme. Both specific granules and azurophils are bounded by membranes. Band III can be further resolved into 2 narrowly separable bands: IIIs (slow), which contains more myeloperoxidase, neutral protease, and β glucuronidase; and IIIf (fast), which contains lysozyme. Histochemically, both IIIs and IIIf granules contain peroxidase. Measured immunochemically, lactoferrin and myeloperoxidase, respectively, appear to afford unambiguous markers for specific and azurophil granules of PMN. Although various blood cells may contaminate suspensions of PMN, only specific granules of eosinophils created problems.
|Original language||English (US)|
|Number of pages||12|
|State||Published - Dec 1 1974|
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Molecular Biology
- Cell Biology