Metabolic heterogeneity of eosinophils from normal and hypereosinophilic patients

Abstract

Eosinophils, which may be associated with allergic, parasitic, or neoplastic disease, have a potent oxidative burst that may be activated by particulate or soluble stimuli. Eosinophils from normal persons and patients with hypereosinophilia were compared with respect to their ability to produce the active oxygen product, superoxide anion. Normal eosinophils produced large amounts of superoxide anion under resting conditions (0.53 +/- 0.15 nmoles cyto-c/10(5) eos/hr) and when stimulated by preopsonized zymosan (0.85 +/0 1.10 nmoles cyto-c/10(5) eos/hr) or phorbol myristate acetate (PMA) (2.38 +/- 0.46 nmoles cyto- c/10(5) eos/hr). Considerable variation was observed in superoxide production by eosinophils from patients with hypereosinophilia. Eosinophils from a group of four patients with hypereosinophilia associated with neoplastic disease produced less superoxide anion than normal eosinophils when stimulated by preopsonized zymosan or PMA (p less than or equal to 0.05). Eosinophils from a group of 5 patients with other causes of hypereosinophilia produced more superoxide anion than normal eosinophils when stimulated by PMA (p less than or equal to 0.01). These studies demonstrate metabolic heterogeneity of eosinophils from patients with hypereosinophilia, and further emphasize that normal eosinophils and eosinophils from hypereosinophilic patients are not functionally equivalent.

Evaluation of myeloid cells (tumor-associated tissue eosinophils and mast cells) infiltration in different grades of oral squamous cell carcinoma

“…[64] Various causes for tumor-associated eosinophilia have been postulated: been sporadic, and it is likely that several causes are responsible. [65,66] Regardless of the cause of accumulation or the mechanism by which eosinophils traffic to tumors, a salient question remains: What are the consequences of this eosinophil infiltration? Specially, are eosinophils destructive, cytotoxic effector cells limiting tumor growth as part of a host surveillance mechanism, or do the infiltrating eosinophils facilitate tumor growth by remodeling and immunoregulation of the tumor microenvironment?…”

Bactericidal action of eosinophils from normal human blood

“…Few studies have been performed on the bactericidal action of eosinophils. These studies were done with cells from patients with eosinophilia, cells which are different from normal eosinophils (2,16,17). We have now studied the bactericidal capacity of eosinophils and neutrophils from the same healthy donors.…”

“…Few studies have dealt with the possible bactericidal action of eosinophils, comparing the capacity of eosinophils and neutrophils to ingest and kill various microorganisms (1,7,15). However, in these studies, eosinophils which differ from the eosinophils of normal individuals were obtained from patients with eosinophilia (2,16,17). Moreover, the purity of the cell suspensions used was between 40 and 90%.…”

Modulation of eosinophil function in vitro

“…Eosinophils exhibit considerable heterogeneity and ean be separated into distinct populations by density gradient centrifugation. There is evidence that the lower density ceils are activated in terms of metabolic activity and IgG Fc and complement receptor expression [14][15][16], Much of the work characterizing IgG Fc and complement receptors on eosinophils has used the rosette technique [17], which is a relatively imprecise method for determining receptor expression. There are few data on the expression of the leucocyte integrins on eosinophits [18 20].…”