The theory that various hematologic malignancies, such as acute and chronic
leukemias and lymphomas, are characterized by monoclonal expansion of neoplastic cells
arrested at different levels along the hemo-lymphopoietic differentiation pathway is widly
accepted. It has also been supported by immunoglobulin gene rearrangement and
phenotyping with specific antibodies to surface markers of lymphocytes concerning the
lymphoid malignancies. In cope with these developments, the immunologic classification
of acute lymphocytic leukemia has become more clarified.
The author studied the immunologic classification of 15 Patients with acute
lymphocytic leukemia(ALL) with monoclonal antibodies against surface markers for
lymphoid cells, and tried the in vitro induction of differentiation of progenitor-B cell
ALL and T-cell ALL with TPA(12-0-tetradecanoyl phobol-13-acetate), a well known
tumor promoter and known as a differentiation inducer also. Monoclonal antibodies for
surface markers, used in this study, were Leu-9 for T-cell ALL and anti-la,
anti-CALLA, anti-SIg(surface immunoglobulin), anti-Bl, and anti-B4 for B-cell lineage
ALL. Leu-9 positive cases were classified as T-cell ALL, Ia only positive cases were
classified as progenitor-B cell ALL, Ia and CALLA positive cases were classified as
common ALL, and Ia and SIg positive cases were classified as B-cell ALL. The results
were as followings,
1. In this study, 5 cases were classified as common ALL, 3 each cases were B-cell
and progenitor-B cell ALL, and 4 cases were T-cell ALL.
2. All 3 cases of B-cell ALL were L2 by FAB classification, and this findings was
discordant with the conventional knowledge.
3. Leukocyte count in pheripheral blood of T-cell ALL patients at diagnosis was
higher than that of non-T cell ALL(p<0.05).
4. All 5 cases of common ALL and 3 cases of B-cell ALL, 2 of 3 cases of
progenitor-B cell ALL, and 1 of 4 cases of T-cell ALL achieved complete remission. So,
T-cell ALL showed lower remission rate than that of common ALL and B-cell ALL.
5. One case of progenitor-B cell ALL, which is positive to only Ia, newly expressed
B4, CALLA. Bl and SIg after culture with TPA. This results suggest that TPA induce
the differentiation of progenitor B-cells to more differentiated stage.
6. One case of T-cell ALL, which is positive to only Leu-9, newly expressed T3 after
culture TPA and PHA. This results suggest that TPA and PHA induce the
differentiation of early thymocyte to mature thymocyte.
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