ABSTRACT
To explore the possibility of in vitro induction of cord blood cell-derived lymphocytes into cytotoxic T lymphocytes (CTL) with anti-leukemia specificity, umbilical cord blood (UCB)-derived mononuclear cells were cultured with multiple cytokines to generate dendritic cells (DC) in vitro. Leukemia cells were irradiated with (137)Cs and activated by premature cytokines. The characteristics of maturation of DC were evaluated through morphology examination and flow cytometry. DC pulsed with leukemic antigens were co-cultured with lymphocytes. Cytotoxicity of the CTL to corresponding leukemic cells was measured with lactate dehydrogenase-release assay. The results showed that UCB-derived monocytes could be induced into typical DC in all of the 12 samples. Expression of immunological markers such as CD1a(+), HLA-DR(+), CD86(+), CD83(+) on DC were significantly up-regulated (P < 0.05). DC presenting leukemic antigens generated leukemia-specific CTL with a killing rate of (44.76 +/- 17.42)% at the E:T ratio of 50:1 against AML cells and a killing rate of (8.50 +/- 4.25)% at the E:T ratio of 50:1 against ALL cells. Whereas, these CTL present almost no killing effect on the mononuclear cells collected from the same patients in complete remission phase. It is concluded that (1) it is possible to induce UCB-derived monocytes into mature DC with typical morphology. (2) Cord blood derived mature DC presenting leukemia antigen can generate leukemia-specific CTL with vigorous cytotoxic activity against the same leukemia blasts and low killing activity against bone marrow cells of the same patients in complete remission phase.
Subject(s)
Female , Humans , Male , Cells, Cultured , Coculture Techniques , Cytotoxicity, Immunologic , Allergy and Immunology , Dendritic Cells , Cell Biology , Allergy and Immunology , Fetal Blood , Cell Biology , Allergy and Immunology , K562 Cells , Leukemia , Allergy and Immunology , Pathology , Leukocytes, Mononuclear , Cell Biology , Allergy and Immunology , T-Lymphocytes, Cytotoxic , Allergy and ImmunologyABSTRACT
The aim was to study the morphological, histochemical and immunological characteristics of less-differentiated acute myeloid leukemic cells, and their diagnostic significance. Wright-Giemsa and histochemical staining were used to stain bone marrow smears from 2 case of AML-Mo. Immunological phenotypes were determined with flow cytometry. The results showed that myeloperoxidase stainings of both cases were negative, PAS was positive with fine particles, CD33/CD13 were positive, CD2/CD3/CD10/CD19/CD22 were negative. It is concluded that morphology, histochemistry and immunological phenotype on bone marrow smears are the main diagnostic basis for AML-Mo. The use of multiple monoclonal antibodies for staining may improve the accuracy.