Precise separation of rare cells: Lectin method
Cytogenetic test or transplantation treatment by using rare cells circulating in venous blood
Rare cell fractions circulating in the peripheral blood will contribute to clinical examinations or medical treatments.
Rare cell fractions | Use |
Fetal erythroblasts entering maternal circulation. | Non-invasive cytogenetic test concerning congenital anomalies. |
The metastatic cells departing from a tumor tissue. | Indications of drug efficacy or relapse. |
Natural killer cells which attacks cancer cells alone. | The cellular immunotherapy using extracorporeally activated killer cells. |
Hematopoietic stem cells of the bone marrow aspirate or umbilical cord blood. |
Suppression of graft versus host disease based on the depletion of donor lymphocytes. |
- "Development goal of NeTech"
- is the precise isolation of the rare cells which is hard to separate by using antibodies.
Principle of cellular isolation using lectins
- Isolation of cells expressing carbohydrates by using lectins which selectively bind to BIBthe carbohydrates
- Lectins having plural carbohydrate-binding domains attach cells to the solid
- BIBsupport modified with carbohydrates.
- NeTech supplies the solid supports modified with carbohydrates.
- Carbohydrate expression of cells is different according to their types or maturities.
- Choice of lectins enables to perform versatile cell separation, because lectins have BIBselective affinities according to carbohydrate types and its linkage manners.
- TRANSFUSION 2008;48:561-566
Design of cell isolation and enrichment
Negative selection
- Isolation of immature hematopoietic stem cells expressing sparse carbohydrates from leukocytes expressing abundant carbohydrates is achieved by increasing the applied dose of lectin. Thereby, nonadherent stem cells are isolated from adherent leukocytes.
Positive selection
- In the case of collecting erythroydes expressing abundant carbohydrates than leukocytes, adherent erythloides are isolated from nonadherent leukocytes by suppressing the applied dose of lectin.
Schematic illustration of Lectin-Based Erythroblast Isolation
- G-coat by means of glucide-carrying polystyrene enables to easily cover the solid BIBsupports, such as glasses or plastics.
- G-coat according to the carbohydrate-specificity of lectins is available.
- Lectin method promises a practical rare cell isolation.
- The antibody has one binding domain to antigen, but the lectin has plural binding BIBdomains to carbohydrates.
- BIB(The Journal of Biological Chemistry 1976; 253(10):3466-3476)
- Lectins are low-priced than antibodies.
Basic function of lectin
Prenatal test
Efficiency of lectin
practicability
Ripple effect