Presence and localization of human leukocyte populations in human fetal bronchial tissue during gestation and after implantation in the SCID host
| Leukocyte populations . | Bronchial tissues during gestation . | Bronchial grafts . | ||
|---|---|---|---|---|
| Early stage (1st appearance) . | Medium stage . | Mature stage . | Mature stage . | |
| CD3+ | IE, ME (10 wk) | IE, SB, ME | IE, SB, ME | (IE), (SB) |
| CD15+ | — | — | — | — |
| CD20+ | — | — | — | — |
| CD38+ | — | — | — | — |
| CD56+ | — | — | — | — |
| CD68+ | ME (7 wk) | (IE), SB, ME | (IE), SB, ME | (IE), SB, ME |
| Tryptase+ | (ME) (13 wk) | SB, ME | SB, ME | SB, ME |
| Leukocyte populations . | Bronchial tissues during gestation . | Bronchial grafts . | ||
|---|---|---|---|---|
| Early stage (1st appearance) . | Medium stage . | Mature stage . | Mature stage . | |
| CD3+ | IE, ME (10 wk) | IE, SB, ME | IE, SB, ME | (IE), (SB) |
| CD15+ | — | — | — | — |
| CD20+ | — | — | — | — |
| CD38+ | — | — | — | — |
| CD56+ | — | — | — | — |
| CD68+ | ME (7 wk) | (IE), SB, ME | (IE), SB, ME | (IE), SB, ME |
| Tryptase+ | (ME) (13 wk) | SB, ME | SB, ME | SB, ME |
Leukocyte populations expressing CD3 (T lymphocytes), CD15 (granulocytes), CD20 (B cells), CD38 (plasma cells), CD56 (NK cells), CD68 (macrophages), and tryptase (mast cells) were localized in the intraepithelial (IE), subepithelial (SB), and mesenchymal (ME) compartments of human fetal tracheas and stem bronchi at early (6-15 wk), medium (15-23 wk), and mature (23-38 wk) stages of epithelial differentiation27 and in the bronchial grafts, having attained full maturation of surface epithelium and submucosal glands (GA, 16-25 wks; DE, 8-36 wks) as previously described.13 14 Parentheses indicate scarce presence in a compartment.