Cytochemical and ultrastructural studies of aberrant granules in the neutrophils of two patients with myeloperoxidase deficiency during a preleukemic state: relationship to abnormal bactericidal activity

Lactoferrin-deficient neutrophil polymorphonuclear leucocytes in leukaemias: a semiquantitative and ultrastructural cytochemical study

Semiquantitative analysis of lactoferrin deficiency in neutrophil polymorphonuclear leucocytes in various haematological and non-haematological disease was carried out by scoring polymorphonuclear leucocytes stained for lactoferrin by the immunoperoxidase method. The staining patterns for lactoferrin were classified into four types (0-III) based on the intensity of reaction, and the sum of the ratings of 100 polymorphonuclear leucocytes was considered as "lactoferrin score" with a possible range of 0-300. As a result, significantly low lactoferrin-scores were frequently observed in acute leukaemias and the acute phase of chronic leukaemias. Of 35 cases with leukaemias, lactoferrin-negative polymorphonuclear leucocytes (type 0) were observed in the following cases: eight cases of acute myelogenous leukaemia (8/14), a case of chronic myelogenous leukaemia (1/10) in blast crisis, one of acute promyelocytic leukaemia (1/1), one of acute monocytic leukaemia (1/2), and a case of chronic myelomonocytic leukaemia (1/2) in a transitional phase to an acute myelomonocytic leukaemia. In two cases of acute myelogenous leukaemia, in which the majority of polymorphonuclear leucocytes were negative for lactoferrin, ultrastructural cytochemical study revealed total lack of specific granules in these polymorphonuclear leucocytes. This suggests that lactoferrin is localised in the specific granules of neutrophils as has been postulated previously by others.

Defective neutrophil function and microbicidal mechanisms in the myelodysplastic disorders

Neutrophil function studies have been carried out in a series of 44 patients with primary myelodysplastic syndromes (MDS). In vitro tests of phagocytosis and killing of Candida guilliermondii and Staphylococcus aureus identified 13 patients with abnormal neutrophil function at presentation and a further 10 who developed abnormalities during the course of their disease. The incidence of defective function in the five disease categories in this series was: refractory cytopenia (RC) 8/17; refractory cytopenia with sideroblastic change (RC + SC) 5/8; acquired idiopathic sideroblastic anaemia (AISA) 2/4; refractory anaemia with excess blasts (RAEB) 7/11; chronic myelomonocytic leukaemia (CMML) 1/4. Eleven of 23 patients with defective neutrophil function experienced severe infective complications; in only three of these patients were neutrophil counts less than 1 X 10(9)/l and susceptibility to infection was considered to reflect, at least partially, qualitative neutrophil abnormalities. There was no correlation between absolute neutrophil count and defective function. Abnormal overall neutrophil microbicidal activity was equally associated with impaired and normal phagocytosis. Some patients with intracellular killing defects had reduced myeloperoxidase (MPO) activities and one had reduced hexose monophosphate shunt (HMPS) activity. In two patients, whose neutrophils showed markedly impaired candidacidal activity, levamisole corrected function when added in vitro at 10(-7) M and also when administered in therapeutic dosage. It is suggested that deranged function, probably reflecting abnormalities in maturation of the granulocyte series, occurs across the myelodysplastic spectrum and that several microbicidal mechanisms may be defective.

Partial myeloperoxidase deficiency in preleukemia

In seven subjects with partial and apparently acquired form of myeloperoxidase (MPO) deficiency, some functional properties of neutrophils (PMNs) were studied. Five patients suffered from preleukemia, one from diabetes mellitus and one from carcinoma of the breast with bone marrow metastases. Intracellular bactericidal activity, oxygen consumption and superoxide radical production were within normal limits. In three patients with preleukemia, the serum opsonic activity was markedly reduced (less than m-3SD) in an autologous system, but normal in the presence of pooled normal serum. Decreased opsonic activity was also found when these patient's sera were assayed in the presence of normal PMNs. Since the levels of IgG and C3 were comparable in the patients' sera and the pooled serum, a deficiency of another unknown opsonin or the presence of an opsonization inhibitor has to be postulated. The partial MPO defect apparently doesn't decrease the intracellular killing of Staphylococcus aureus by PMNs. The known susceptibility to bacterial infections in preleukemia may be explained by the reduction of serum opsonization conducing to a secondary decrease of the ingestion and killing of bacteria by the PMNs.

Ultrastructure of blastic crisis in osteomyelofibrosis. A report of 2 cases with some unusual features

The clinical and morphological findings are presented in two patients suffering from myelofibrosis and osteomyelosclerosis which terminated in an acute blastic crisis. Clinical follow-up data and light microscopy of the bone marrow however, revealed a chronic megakaryocytic-granulocytic myelosis (CMGM) with progression into myelofibrosis during the course of disease. In one patient the blastic transformation involved predominantly basophils, and in the other, neutrophils, with an accompanying abnormal proliferation of megakaryocytes in both cases. Electron microscopy of this cell population demonstrated remarkable atypicalities of the neutrophilic, basophilic and megakaryocytic cell lines. These abnormalities consisted of a nuclear-cytoplasmic asynchrony and a partial arrest of maturation, sometimes resulting in bizarre cell forms. Our investigations support the hypothesis of a mixed cellularity type of myelosis with a gradual and insiduous progression into osteomyelofibrosis/-sclerosis and a potential blastic crisis. In the evolution of blastic crisis all cell lines may be transformed, but with predominance of one population - basophils and neutrophils in our two cases - in addition to atypicalities of megakaryocytes.

The ultrastructure of guinea pig heterophil granulocytes and the heterogeneity of the granules

The development of the heterophil granulocytes in the bone marrow of the guinea pig is described. During the maturation of these cells, three types of granule are formed, not only the azurophil and specific granules already described in other mammals but also a third type of granule referred to here as the nucleated granule. During the process of maturation of the cells, these three types of granule are formed successively. On this basis, two steps can be distinguished in the promyelocyte phase in which primary (nucleated and azurophil) granules are formed, i.e. an early and late stage, nucleated granules being formed in early and azurophil granules in late promyelocytes. Secondary (specific) granules occur first in myelocytes. In mature heterophils of the guinea pig the granule population is composed of about 85% secondary granules, about 10% azurophil granules, and about 5% nucleated granules. The changes in the granule population during the maturation process were quantified. The observations and calculations point to the occurrence of three mitoses: one in the early and one in the late promyelocyte and the third in the myelocyte.