BACKGROUNDThe SLAM family recently has been reported to show an important biological role in lymphocyte development and immunological function, and it is efficient to highly purify hematopoietic stem cells using a simple combination of SLAM family members. To elucidate the presence of this family on acute lymphoblastic leukemia (ALL), as well as its relationship with the leukemia-initiating potential, we analyzed the expression pattern of this family members on human ALL progenitor cells, combined with serial xenotransplantation assay.

METHODSExpression analysis was carried out by flow cytometry. We combined the expression pattern of human CD(150), CD(244) and CD(48) with serial xenotransplantation of B-ALL progenitor cells to indicate their relationship.

RESULTSCD(48) and CD(244) were expressed on most B-ALL progenitor cells, the percentage being (93.08 ± 6.46)% and (63.37 ± 29.31)%, respectively. Interestingly, the proportion of CD(150)(+) cells declined obviously in engrafted cases ((24.94 ± 7.32)%) compared with non-engrafted cases ((77.54 ± 5.93)%, P < 0.01), which indicated that only blast cells with low percentage of CD(150)(+) population were able to reconstitute leukemia into primary, secondary and tertiary NOD/SCID mice.

CONCLUSIONSSLAM family members are present on B-ALL progenitor cells and the leukemia-initiating potential of leukemic blasts is correlated negatively with the proportion of CD(150)(+) cells, the percentage of which can serve as a useful predictor for engraftment success of B-ALL to immune deficient mice.

Adolescent ; Adult ; Aged ; Animals ; Antigens, CD ; analysis ; CD48 Antigen ; Child, Preschool ; Female ; Flow Cytometry ; Humans ; Infant ; Male ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; blood ; Receptors, Cell Surface ; analysis ; Receptors, Immunologic ; analysis ; Signaling Lymphocytic Activation Molecule Family ; Signaling Lymphocytic Activation Molecule Family Member 1 ; Transplantation, Heterologous

Measles virus is an enveloped virus with a non-segmented negative-sense RNA genome. Two envelope glycoproteins on the viral surface, namely hemagglutinin (H) and membrane fusion protein (F), are responsible for the virus entry into susceptible host cells. The specific interaction between H and its cellular receptors is a key step in successful virus infection, determining the infectivity and tissue tropism of the measles virus. Thus far, three H receptors have been identified, including the complement regulatory molecule CD46, the signaling lymphocyte activation molecule (SLAM) and the cell adhesion molecule Nectin-4. Here, we reviewed our molecular understanding on the recognition mechanism of these receptors by the viral H protein, aiming to promote future studies on antiviral drug design and measles virus-based oncolytic therapy.
Animals ; Antigens, CD ; metabolism ; Cell Adhesion Molecules ; metabolism ; Hemagglutinins, Viral ; metabolism ; Humans ; Measles virus ; pathogenicity ; physiology ; Membrane Cofactor Protein ; metabolism ; Membrane Fusion ; Membrane Fusion Proteins ; metabolism ; Receptors, Cell Surface ; metabolism ; Receptors, Virus ; metabolism ; Signaling Lymphocytic Activation Molecule Family Member 1