Hematologic and Immunophenotypic Characterization of Human Umbilical Cord Blood

Abstract

In this work, cord blood cells from 30 healthy term newborns were analyzed for complete blood counts with an automated cytometer and, in part of the sample, for surface molecules in cord blood monocytes, lymphocytes and CD34+ cells by two-color flow cytometry. Hematological parameters were as follows: WBC = 12.85 (5.24–15.10) ×10⁹/l; platelets = 304.33 (156.00–469.00) × 10⁹/l; Hb = 14.45 (11.90–17.82) g/dl; RBC = 3.99 (3.14–5.12) × 10¹²/l; MCV 107.25 (99.60–115.00) fl; reticulocytes = 157.80 (101.00–124.00) × 10⁹/l or 3.99 (2.45–6.01)%; erythroblasts = 0.88 (0.15–2.58) per 100 WBC or 6.63 (2.86–16.80) × 10⁹/l. The mononuclear population, as evaluated by flow cytometry, was composed of 22.9 ± 7.2% monocytes and 77.05 ± 7.24% lymphocytes, among which 46.59 ± 15.62% were T lymphocytes (43.94 ± 16.94% CD3+/CD4+ and 13.45 ± 7.46% CD3+/CD8+). CD34+ cells were on average 0.54 ± 0.24% of the mononuclear fraction. CD11c, CD49e and HLA-DR were found mainly on monocytes, and CD31 and CD62L occurred in similar levels on monocytes and lymphocytes. CD117+ cells were less than 5% of these populations. Among CD34+ cells, CD31 and HLA-DR were the molecules with higher frequencies (79.7 ± 19.9 and 65.7 ± 23.0%, respectively), followed by CD62L (41.8 ± 31.9%) and CD117 (20.1 ± 15.8%). The presence of CD11c and CD49e on CD34+ cells was low (below 10%). The results stress the phenotypic heterogeneity of cord blood CD34+ cells, and the different behavior of the cells when manipulated in vitro in different degrees of isolation.

Erythrocyte indices and serum ferritin in newborns

“…Some of them classified newborns according to their weight-for-gestationalage-categories (3,5,9) while others did not. (6)(7)(8)10) Our results regarding RBC parameters were similar to those reported in some studies (3,8,10) and lower than those observed in others. (5,6,9) We also observed that our results were lower than those usually used as reference standards in neonatology.…”

“…(7) In published studies, information on hematological values in cord blood is limited and inconsistent. The studies that we found (3)(4)(5)(6)(8)(9)(10) evaluated different subgroups of neonates and different hematological parameters. In particular, little data regarding hematological parameters of SGA newborns was found.…”

Immunophenotype of hematopoietic stem cells from placental/umbilical cord blood after culture

“…This frequency is similar to that in harvested pelvic bone marrow (1.0 ± 0.3 vs 0.8 ± 0.4%) (14). About 1% of bone marrow cells express CD34, and generally less than 1% of these cells are CD38-negative (6,11,15). In other studies, Campagnoli et al (16) showed that the concentration of CD34 + cells in whole blood samples in term fetal blood was 0.4 ± 0.03% of total CD45 + cells, and Hao et al (3) showed that the frequency of CD34 + cells among total MNCs in cord blood was 0.36 ± 0.33% with a large variation among samples (range 0.02 to 1.43%; N = 30).…”

“…After transplantation of HSCs, adhesion molecules play a major role in the multistep process of engraftment in which L-selectin is suggested to be of relevance. There is evidence that cord blood, bone marrow and peripheral blood-derived HSCs are highly heterogeneous for a number of antigens useful for HSC enumeration by flow cytometry (6). HLA-DR is expressed in the majority of HUCB (4,13) and peripheral blood (13,19) CD34 + cells.…”

“…Hence, the frequency of the CD34 + CD38 -population is about 1 in 10,000, or even lower. Phenotypic analyses of several cell surface markers reveal that even this rare population is heterogeneous (6). Ex vivo culture is a crucial component of several clinical applications of stem/progenitor cells.…”