Heterogeneity of human peripheral blood eosinophil-type colonies: evidence for a common basophil-eosinophil progenitor

Abstract

We have recently shown that a proportion of previously designated human eosinophil “(Eo)-type” colonies in methylcellulose contain basophils and histamine (Denburg et al Blood 61:775, 1983). In the present studies, individual Eo-type colonies have been analyzed by cell morphology as well as by biochemical assays for histamine, Charcot- Leyden crystal protein (CLC), and eosinophil granule major basic protein (MBP). Clonal origin of single Eo-type colonies was confirmed by G6PD isoenzyme analysis. Morphological observations of such colonies revealed the existence of two distinct colony types: (1) Eo type containing 100% basophils and (2) Eo type containing mixtures of basophils and eosinophils, including cells with mixed basophil- eosinophil granulation. Histamine was not detected in pure, mature peripheral blood eosinophils. Immunofluorescent studies demonstrated bright staining for CLC and MBP in 95% +/- 3% of cells in Eo-type colonies but only in 5% +/- 4% of cells in GM-type colonies. Radioimmunoassay for MBP was positive in 5/9 Eo-type and 0/10 neutrophil-macrophage (“GM-type”) colonies, with a mean level (nanogram/colony) of 11.6 +/- 4.2 per Eo-type colony; four of the latter colonies were doubly positive for both histamine and MBP. These and previous findings point out the morphological and biochemical heterogeneity of peripheral blood Eo-type colonies and provide direct evidence for the existence of a common, circulating basophil-eosinophil progenitor.

Eosinophils and atopic dermatitis

“…Eosinophils are derived from a CD34 + hematopoietic progenitor cell in the bone marrow. Eosinophils share this progenitor with basophils, defined as the eosinophil/basophil‐colony forming unit (Eo/B‐CFU) (29). In the peripheral blood of atopic individuals, the Eo/B‐CFU is elevated and correlates with the severity of the atopic disease.…”

Human mast cell progenitors in peripheral blood from atopic subjects with high IgE levels.

“…Mast cells and basophils are the unique cells that can evoke immediate allergic reaction through surface high affinity IgE receptors [1]. Mast cells and basophils develop from distinct progenitors and basophils often share common progenitors with eosinophils [2–4]. Basophils and eosinophils require IL‐3, GM‐CSF and IL‐5 for their development [5], whereas the development of human mast cells is often independent from IL‐3 [6–8] and always dependent on the presence of a factor called a stem cell factor (SCF) or c‐kit ligand [9–12].…”

Interleukin‐5 in growth and differentiation of blood eosinophil progenitors in asthma: effect of glucocorticoids

“…Our results demonstrate that circulating CD34 + progenitor cells express both intracellular IL‐5 and its receptor, IL‐5Rα with a greater expression in cells from patients with asthma. IL‐5 is uniquely able to promote the terminal differentiation and maturation of progenitors committed to the eosinophil/basophil lineage (Denburg et al ., 1985b; Clutterbuck et al ., 1989), and acts through the IL‐5 receptor which is made of heterodimeric structures consisting of a low‐affinity α – subunit, and a common shared β‐subunit which forms high‐affinity cytokine binding sites in association with the α‐subunit (Tavernier et al ., 1991). The cytoplasmic domain of the α‐subunit is essential for signal transduction, mediating growth signals stimulated by (Takaki et al ., 1994).…”