Subclassification in acute lymphoblastic leukaemia: acid phosphatase reaction and immunological markers in relation to clinical features. A comparative study of 44 patients

Lineage ambiguity in acute leukemia

Two cases of acute nonlymphocytic leukemia that showed surface phenotypes characteristic of lymphoid cells are reported. The cases, both involving female patients were studied by a variety of methods including flow cytometry and karyotyping. In Case 1, the patient, a 10-year-old girl, had poorly differentiated myeloblasts (FAB M1), which were weakly positive for Sudan black B (SBB), but negative for alpha naphthyl acetate esterase (NAE) and naphthol ASD chloroacetate esterase (CAE). Myeloperoxidase was demonstrated ultrastructurally in some of the blasts. In Case 2, the 30-year-old patient had typical myelomonocytic leukemia (FAB M4), with SBB-, NAE-, and CAE-positive blasts. Both cases were negative for terminal deoxynucleotidyl transferase. Case 1 was negative for myeloid membrane markers, whereas Case 2 was strongly positive for My7 and My9. Surprisingly, both cases showed significant positivity for B-cell restricted antigens B1, B2, and B4. These findings suggest ambiguous or dual lineage, supporting the concepts that some leukemias could arise from a pluripotent hematopoietic progenitor cell (Case 1) or from cells that though differentiated in some respects, could still preserve some early antigens (Case 2).

Activity of acid phosphatase in resting and mitogen-stimulated human peripheral blood lymphocytes

Activity of acid phosphatase was found to be higher in T than in non-T cells of human peripheral blood lymphocytes. The T cell mitogen PHA induced an increase in the magnitude of acid phosphatase activity, while the B cell mitogen LPS was not able to produce any effect on acid phosphatase activity. Acid phosphatase activity in lymphocytes correlated with their spontaneous proliferative activity.

beta-D-N-acetylglucosaminidase, a new cytochemical marker of human lymphocyte subpopulations

beta-D-N-acetylglucosaminidase staining characteristics of rosetted or non-rosetted normal and malignant lymphoid cells were compared with those observed after nonspecific esterase and acid phosphatase staining. With the three cytochemical techniques a similar staining pattern was observed in T cells (E-rosettes), their subpopulations T mu and T gamma, B cells and the non-T, non-B cells, as well as in the T cell populations defined with the monoclonal antibodies OKT3,4 and 8. T mu cells mostly displayed a "dot-like" reaction, T gamma and the non-T, non-B cells a "fine to heavy granular" reaction, while most B cells were negative. OKT4 and OKT8 positive lymphocytes showed for the larger part a dot-like staining pattern, however, the frequency of cells with a granular pattern was distinctly higher in the OKT8, than in the OKT4 positive cells. E(+)mIg(-) and E(-)mIg(-) A.L.L. blasts stained either with a dot-like or granular pattern or failed to react when stained cytochemically for beta-D-N-acetylglucosaminidase, nonspecific esterase and acid phosphatase activity. Only in a few instances a discrepancy was observed between the types of staining for esterase and acid phosphatase on one hand and those for beta-D-N-acetylglucosaminidase on the other.

Immunological markers in acute leukaemia

61 acute leukaemias were classified by both immunological and morphological criteria. In 58 (95%) of the cases correlation was found between the immunological and morphological diagnosis. In 3 (5%) cases, no correlation was found between the immunological subclasses and the FAB-subgroups in ALL. Neither was a correlation found between FAB-subclasses in AML and reaction with myeloid antibodies other than MY-7 which did preferentially react with M4 and M5 leukaemia.

Acid phosphatase and acid esterase activity in neoplastic and non-neoplastic lymphoid cells. A semiquantitative evaluation related to immunological markers in 112 cases

Acid phosphatase (AcP) and acid alpha-naphthylacetate esterase (ANAE) were examined in lymphoid cells from 104 patients suffering from various lymphoproliferative disorders and from 8 healthy controls. Enzyme activities were evaluated by means of a scoring system. Scores of AcP and ANAE were higher in normal T cells than non-T cells. In comparison, the activated T cells in infectious mononucleosis showed increased AcP and decreased ANAE reaction. Malignant T lymphoblasts had a distinct granular AcP positivity in contrast to the faint reactivity observed in cALL blasts, whereas ANAE showed negative or weak reaction in both subsets. High scores and distinct staining patterns for both enzymes were found in T CLL and T prolymphocytic leukaemia, clearly different from the weak activities seen in B CLL, B PLL and some B cell lymphomas. The latter, too, could be distinguished by mutual differences in enzyme reactions. High AcP and ANAE scores were also found in hairy cell leukaemia, and the staining patterns together with the tartrate resistance firmly established the diagnosis. Thus, simultaneous determinations of AcP and ANAE can be of great value in the diagnosis of lymphoid malignancies.

Stereologic analysis of the ultrastructure in isolated human T and non-T lymphoid cells. II. Data on blasts in ALL; correlation with immunologic studies and FAB-morphology

Leukemic cells from 20 cases of acute lymphoblastic leukemia (ALL), examined for T and B markers and classified according to FAB guidelines, were analyzed by electron microscopy. Using stereologic methods a quantitative morphologic characterization of the average blast, assumed to be of clonal origin and thus representative of the whole population, was obtained within each subset. Comparative studies of the ultrastructure of the T, B and non-T, non-B blast on one hand and of the FAB category L1 and L2 on the other were performed. No differences of cell volumes, total cell surface areas, nuclear volumes and surface areas or volumes of nuclear compartments were observed between the immunologically defined subsets. Minor variations were seen in the cellular surface contour, the B blast tending to be more irregular than the T blast. Features most predictive of the immunologic cell type were abundant rough ER in B-derived ALL, increasing with plasmacytoid differentiation, and an increase in dense granules which were often clustered in the vicinity of a well-developed Golgi complex in T ALL. The light microscopic criteria of the FAB classification were nearly all confirmed at the EM-level except that nuclear irregularity was observed to the same degree in both categories. Other differences not related to the FAB scheme were encountered in the volumes of the Golgi complex and of the mitochondrial compartment. Objective criteria as quantitative estimates of cellular structures may contribute to an improved subclassification in ALL.

Differential diagnostic value of acid phosphatase and beta-glucuronidase in acute leukaemia

Differential diagnostic importance of acid phosphatase and beta-glucuronidase reactions was studied in bone marrow smears of 52 patients with acute leukaemias. Both reactions showed either diffuse or simultaneously diffuse and granular positivity in the medullary blast cells of 34 patients suffering from ANLL. A strong diffuse positivity of acid phosphatase suggested the possibility of AMOL. Beta-glucuronidase and acid phosphatase reactions were exclusively granular in every positive case of ALL. Increased acid phosphatase activity was found in T-ALL while beta-glucuronidase showed increased activity also in (non-T, non-B)-ALL on several occasions.