Premium
Surface expression of HLA‐DM on dendritic cells derived from CD34‐positive bone marrow haematopoietic stem cells
Author(s) -
Min Yoo Hong,
Lee Seung Tae,
Choi Kyung Mi,
Hahn Jee Sook,
Ko Yun Woong
Publication year - 2000
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1046/j.1365-2141.2000.02180.x
Subject(s) - haematopoiesis , bone marrow , cd34 , stem cell , stem cell factor , cd80 , biology , microbiology and biotechnology , cd86 , interleukin 3 , immunology , progenitor cell , antigen presenting cell , t cell , cd40 , cytotoxic t cell , in vitro , immune system , biochemistry
HLA‐DM has been known to be largely absent from the cell surface of antigen‐presenting cells, accumulating instead in the intracellular compartment. In this study, we demonstrated that a population of HLA‐DM‐positive (HLA‐DM + ) dendritic cells (DCs) can be identified in an in vitro culture of CD34 + bone marrow haematopoietic stem cells. CD34 + bone marrow cells of healthy donors were used to generate DCs with the recombinant human cytokines granulocyte–macrophage colony‐stimulating factor (GM‐CSF), tumour necrosis factor α (TNF‐α) and stem cell factor (SCF), both with and without interleukin 4 (IL‐4). Flow cytometric analysis demonstrated that HLA‐DM + cells comprised 2·5 ± 0·9% and 1·8 ± 0·4% of the CD34 + cell‐derived progeny in the presence of GM‐CSF, TNF‐α and SCF after 7 d and 14 d of culture respectively. The number of HLA‐DM molecules expressed per HLA‐DM + cell on d 7 was significantly higher than that on d 14 (1410 ± 47 versus 370 ± 25, P < 0·05). The addition of IL‐4 to the cytokines from the commencement of culture increased the proportion of HLA‐DM + cells and increased the number of HLA‐DM molecules per HLA‐DM + cell significantly ( P < 0·05). Although most of the HLA‐DM + cells expressed CD1a, CD80 or CD86 antigen, only a small proportion of CD1a + , CD80 + or CD86 + cells expressed HLA‐DM. About half the HLA‐DM + cells expressed CD83. The addition of IL‐4 resulted in a decrease in the expression of CD83 on the HLA‐DM + cells on d 7. Microscopic evaluations of sorted HLA‐DM + cells revealed the characteristic morphological features of DCs. Primary mixed lymphocyte cultures demonstrated that the HLA‐DM + cells elicited a vigorous proliferation of allogeneic T cells. The level of antigen‐specific T‐cell activation induced by antigen‐pulsed, chloroquine‐treated HLA‐DM + cells was substantially higher than that induced by HLA‐DM − cells ( P < 0·05). These results show that HLA‐DM can be used as a useful DC lineage‐specific marker, as well as a tool for the characterization of DCs and human immunotherapy.