The lymphocyte production pathway in bone marrow: possible significance of the size spectrum of lymphocytes and their precursors

Radioautographic studies on the formation and maturation of bone marrow lymphocytes in mice

DNA labelling by [3H]thymidine and the sandwich radioimmunolabelling method were used to characterize marrow lymphoid cells and to study the kinetics of production and maturation of small lymphocytes in the bone marrow of adult mice. Marrow lymphoid cells consisted of non-proliferating small lymphocytes, 30-40% of which had detectable surface immunoglobulin (SmIg), and proliferating large lymphoid cells lacking SmIg. Double-labelling experiments employing [3H]thymidine in vivo followed by sandwich radioimmunolabelling in vitro indicated that marrow small lymphocytes lack detectable SmIg when they are formed but develop SmIg within the first few days after production. Marrow lymphocytopoiesis includes; (1) proliferation of large lymphoid cells, which are presumptive small lymphocyte progenitors, which have a cell cycle time of 14-15 hr, and (2) a 3-5 day intramyeloid stage when many newly formed small lymphocytes undergo maturational changes towards the B cell lineage.

Assessment of bone marrow histology in the malignant lymphomas (non-Hodgkin's): correlation with clinical factors for diagnosis, prognosis, classification and staging

Bone marrow biopsies of 678 untreated patients with established malignant non-Hodgkin's lymphomas (ML) were investigated. The bone marrow was involved in 468 cases, an overall frequency of 69%. The Kiel classification of the ML (based on lymph node histology) was applied and the biopsies were classified: ML lymphocytic 36%, ML 'hairy cell' 24%, ML lymphoplasmacytic/cytoid 24%, ML centrocytic 6%, ML centroblastic/centrocytic 4%, ML lymphoblastic (without ALL) 3%, ML centroblastic 2% and ML immunoblastic 1%. The life tables of the patients were similar whether classified according to the histology of the lymph node or the bone marrow. A multivariate computer based analysis of both clinical and histological data was performed to test their prognostic relevance. The cell type, the proliferation pattern and the extent of infiltration in the bone marrow all proved to be factors of prognostic significance. The results indicate that classification of the ML based on lymph node histology is applicable to the bone marrow, is reproducible and has prognostic significance. Consequently, a bone marrow biopsy is a useful clinical tool for staging and for histological classification of patients with ML.