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A High Yield and Cost-efficient Expression System of Human Granzymes in Mammalian Cells
Published on: June 10, 2015
Expression of granulysin mRNA in the human megakaryoblastic leukemia cell line CMK
Noriko Kitamura1, Masahiro Koshiba, Osamu Horie
1Department of Medical Technology, Faculty of Health Sciences, Kobe University School of Medicine, Kobe, Japan.
Abstract:
Granulysin is a newly reported cytolytic molecule and colocalizes with perforin and granzymes in the granules of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. In this study, we found that the megakaryoblastic leukemia cell line CMK, established from a patient with Down's syndrome, expressed granulysin mRNA. CMK was positive for CD13 and CD41 and negative for CD56. CMK also expressed CD2 and CD7. However, no rearrangement of the T-cell receptor beta-chain gene, an early marker of T-cell lineage, was found in CMK cells. Thus, CMK is assumed to originate from the clonal evolution at the immature cell level. The expression of granulysin in CMK cells suggests that granulysin is occasionally present in immature multilineage cells or may be characteristic of leukemic cells obtained from Down's syndrome patients. CMK has been reported to be capable of differentiating to mature megakaryocytes and produce platelets with normal function. It therefore seems to be possible that granulysin is also present in normal platelets. Unfortunately, we were not able to obtain evidence that normal platelets contain granulysin mRNA and its antigen.
Insights
This study found granulysin mRNA in CMK leukemia cells from a Down's syndrome patient. Granulysin expression may occur in immature cells or be characteristic of Down's syndrome leukemia.
Area of Science:
- Immunology
- Hematology
- Molecular Biology
Background:
- Granulysin is a cytolytic molecule found in cytotoxic T lymphocytes (CTL) and natural killer (NK) cells.
- Its presence in other cell types, particularly in leukemic contexts, is not well-established.
Purpose of the Study:
- To investigate granulysin expression in the CMK cell line, derived from a patient with Down's syndrome.
- To explore the potential presence of granulysin in immature multilineage cells or its association with Down's syndrome-related leukemia.
Main Methods:
- Analysis of granulysin mRNA expression in the CMK cell line.
- Immunophenotyping of CMK cells using CD markers (CD13, CD41, CD56, CD2, CD7).
- Assessment of T-cell receptor beta-chain gene rearrangement.
Main Results:
- Granulysin mRNA was detected in the CMK megakaryoblastic leukemia cell line.
- CMK cells expressed myeloid (CD13, CD41) and T-cell (CD2, CD7) markers but lacked T-cell receptor gene rearrangement, suggesting immature cell origin.
- No evidence of granulysin mRNA or antigen was found in normal platelets.
Conclusions:
- Granulysin expression in CMK cells suggests its potential presence in immature multilineage cells or as a characteristic of Down's syndrome leukemia.
- Further research is needed to clarify the role and presence of granulysin in normal platelets.
