The North Karelia Youth Programs

Two family-based and two community- and school-based studies have been done in the province of North Karelia in eastern Finland. In the two family-based studies it was possible to decrease serum cholesterol level among children by 15%, showing that to a great extent the extremely high blood cholesterol level among Finnish children can be explained mainly by the typical Finnish diet high in saturated fat. In the first North Karelia Youth Project it was possible to affect the onset of smoking among adolescents. Two years after the program, smoking was about 30% less common in the intervention school than in the reference schools. In the eighth-year follow up survey the effect of the teacher-delivered program was still seen. In the second North Karelia Youth Project it was possible to delay the onset of smoking during the seventh grade but no permanent effect was seen. Diet was changed more among the program school students than in the reference school. These studies, done during the last 10 years, show the cardiovascular risk factors can be reduced among children and adolescents. The next main question is how to use these findings in the normal school and health care system. We have started the National Healthy School Program in Finland to assess the extent to which these programs can be implemented on the national level.

Recombinant human erythroid potentiating activity enhances the effect of erythropoietin in mice

Endotoxin-free purified recombinant human erythroid potentiating activity (EPA) was administered to mice either alone or concomitantly with recombinant human erythropoietin (Epo). Epo treatment alone caused an increased hematocrit and reticulocyte count in the peripheral blood. In the spleen, the number of morphologically recognizable erythroid cells, CFU-E and BFU-E was also increased. Concomitant administration of EPA with Epo further enhanced erythropoiesis as judged by the same parameters. No significant effect on granulopoiesis was observed in association with Epo or combined Epo and EPA treatment. Our data indicates that EPA is active in vivo in augmenting the erythropoietic response to Epo.

Relationship between cells forming colonies in diffusion chambers in vivo (CFU-D) and cells with high proliferative potential in vitro (HPP-CFC-1 and -2)

In vivo diffusion chambers implanted in normal mice after 5 days of bone marrow cell culture contained precursor cells that in the presence of recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF), interleukin 3 (IL-3), or colony-stimulating factor 1 (CSF-1), alone or in combination, formed both small and large (high proliferative potential colony-forming cells, HPP-CFC) macrophage-containing colonies in vitro. Synergistic factor from serum-free 5637 cell-conditioned medium (SF5637) enhanced HPP-CFC colony growth only in cultures containing CSF-1. Higher numbers of CSF-1- plus IL-3-responsive colony-forming cells (HPP-CFC-2) were detected in diffusion chamber colony-forming unit (CFU-D) colonies than in intercolony areas, suggesting that they were derived from cells that give rise to the diffusion chamber colony. Further study demonstrated that CFU-D colonies contained cells that formed large macrophage-containing colonies (HPP-CFC-1) in CSF-1- plus SF5637-containing cultures. These findings suggest that single cells (CFU-D) forming colonies in diffusion chambers in mice can give rise to both HPP-CFC-1 and to cells probably representing their progeny, HPP-CFC-2.

Diffusion chamber colony-forming unit (CFU-d): a primitive stem cell

Assay of hematopoietic precursor cells in diffusion chambers (DCs) implanted intraperitoneally in experimental animals provides a powerful tool for studying stem cell kinetics in vivo. In this system, the effect of cell migration (which complicates whole animal studies) is eliminated because the membranes utilized in the construction of the chambers are impermeable for cells, while permitting free passage of molecules present in the humoral phase of the host. As judged by light microscopy, conditions in the DC cultures primarily favor macrophage and granulocyte growth. However, the use of in vitro and in vivo subculture to further analyze chamber contents has demonstrated that the system supports proliferation of early hematopoietic progenitors. Additionally, cells capable of rescuing lethally irradiated mice proliferate in DC cultures. Development of the plasma clot DC technique has revealed that most of the growth occurs in colonies which are derived from single cells (CFU-d). Characterization of these cells indicates that they are at least as primitive as other colony-forming cells and, also based on subculture studies, can differentiate along several hematopoietic lineages. In addition to normal CFU-d, both embryonal and leukemic cells can give rise to granulocytes, macrophages, megakaryocytes and erythroid cells in the DC cultures. Evaluation of the effects of humoral factors on hematopoietic cell proliferation and differentiation in the system has led to the identification of both stimulators and inhibitors that may be different from the well-characterized cytokines. Thus, the system seems to be useful for detecting molecules controlling the most primitive stages of hematopoiesis. We believe that the DC culture technique holds enormous potential in the study of stem cell proliferation and differentiation in vivo.

Progenitor cell numbers (CFU-GM, CFU-D, and CFU-Mix) and hemopoietic recovery following autologous marrow transplantation

Forty-one consecutive patients were treated with high-dose chemotherapy with or without total body irradiation followed by autologous marrow transplantation. Four treatment regimens of varying intensity were used. Every patient's harvested marrow was evaluable for nucleated cell and progenitor cell loss during the cell separation and cryopreservation process. Of the 41 patients, 38 were evaluable for peripheral blood count recovery. Multivariate analysis of colony-forming cell assays and recovery of neutrophils and platelets showed a significant association with absolute numbers of post-thaw mixed colony-forming units (CFU-Mix) infused (p less than 0.002). Prefreeze CFU-Mix also correlated with recovery to a lesser degree, as did absolute numbers of nucleated cells. The number of diffusion chamber colony-forming units (CFU-D) prefreeze, but not post-thaw infused into the patient, was associated with recovery of neutrophils (p = 0.0001), but not platelets. When the precursor cell numbers were adjusted for body weight, post-thaw CFU-Mix showed the best correlation with recovery of both platelets and neutrophils. Prefreeze CFU-D per kg was also associated with recovery of neutrophils (p = 0.02). To some extent nucleated cells per kg predicted for recovery with neutrophils and platelets (p less than 0.05). When analyzed according to treatment regimen, cyclophosphamide-BCNU-VP16 (CBV) or cyclophosphamide-total body irradiation (CY/TBI) was associated with prolonged recovery compared to cyclophosphamide-adriamycin-vinblastine (CAV) or etoposide-cyclophosphamide (EC). In this setting only CFU-D number predicted neutrophil recovery (p less than 0.002). We conclude that determination of the number of total nucleated cells, CFU-D, and CFU-Mix, before cryopreservation of the sample is important in predicting hemopoietic reconstitution in autologous bone marrow transplantation.

In vivo effect of human erythroid-potentiating activity on hematopoiesis in mice

Endotoxin-free purified recombinant human erythroid-potentiating activity (EPA) was administered to normal and bled mice. In anemic ICR mice EPA treatment led to a significant increase in the number of reticulocytes in the peripheral blood and erythroid precursors in the spleen. Stimulation of CFU-E and BFU-E in the spleen was also observed in C3H/HEJ mice, which excluded the possibility of endotoxin effect. Unchanged, 51Cr-tagged red cell survival and lack of radioactivity in the stool or urine suggests that the EPA stimulation of erythropoiesis was not due to hemolysis or bleeding. Thus, EPA has an effect on erythropoiesis in anemic mice in vivo.

Hematopoetic precursors respond to a unique B lymphocyte-derived factor in vivo

In this study we detected a factor that stimulates the proliferation of bone marrow-derived hematopoietic precursors in diffusion chambers implanted in mice. This factor, called diffusible colony-stimulating factor (D-CSF), was found in medium conditioned in the presence of spleen and peripheral blood cells from mice with B cell leukemia (BCL1). After the administration of D-CSF, the number of colonies formed in the plasma clot inside the chamber (CFU-DG) was increased, as were the number of hematopoietic precursors (CFU-MIX, CFU-S, CFU-C, and BFU-E) as judged by a subculture of diffusion chamber contents. Depletion of macrophages and T cells from the spleen cell suspension did not decrease the production of D-CSF, thereby indicating that it was derived from B cells. Neoplastic BCL1 cells appear to be the source because D-CSF could not be detected in medium conditioned with normal B cells. BCL1-conditioned medium (CM) did not enhance CFU-MIX, BFU-E, and CFU-C colony formation in vitro, which suggested that D-CSF is different from multi-CSF, EPA, or CSF. The addition of BCL1 CM to multi-CSF-, erythroid potentiating activity (EPA), and CSF (EL-4CM)-containing cultures had no effect on CFU-MIX, BFU-E, and CFU-C colony formation, thus indicating the absence of a synergistic or inhibitory activity. On the other hand, EL-4 CM, which stimulates CFU-MIX, BFU-E, and CFU-C in vitro, had no effect on CFU-DG in vivo. Biochemical characterization of BCL1 CM revealed that D-CSF is relatively heat stable and loses its bioactivity with protease treatments. It binds to lentil-lectin, according to gel-filtration chromatography has a relative molecular weight of approximately 43,000, and on reverse-phase high-performance liquid chromatography elutes with acetonitrile. These data also indicate that transformed B cells may serve as a source for hematopoietic regulators that act on hematopoietic precursors in vivo.

Diamine oxidase is important in assessment of polyamine effects on hemopoietic cell proliferation in vitro

A difference was observed in the effect of difluoromethlyornithine (DFMO), a specific inhibitor of ornithine decarboxylase, on human and murine granulocyte-macrophage precursor cell (CFU-C) proliferation in vitro, in the presence of fetal bovine serum (FBS) and horse serum (HS). A dose of DFMO which almost totally abolished CFU-C colonies in cultures containing FBS had no effect or very little effect on CFU-C in cultures supplemented with HS. This effect could be reversed by aminoguanidine reacting with diamine oxidase (DAO), which is present in FBS but not in HS. The importance of DAO in the assessment of polyamine effects is also suggested by decreased colony formation in cultures containing HS and DFMO only after the addition of this enzyme. Additionally, Mo T cell line cultures containing DFMO demonstrated a substantially lower intracellular concentration of putrescine in the presence of FBS rather than HS.

Haematological cell proliferation and differentiation responses to perturbations of polyamine biosynthesis

Combined administration of methylglyoxal-bis-guanylhydrazone (MGBG) (25 mg/kg) with difluoromethylornithine (DFMO), or MGBG alone at a higher dose (50 mg/kg), to mice resulted in a decreased white cell count (WBC) in the peripheral blood while DFMO or MGBG alone at a lower dose (25 mg/kg) had no effect. As expected, DFMO alone increased the number of colony forming units spleen (CFU-s), colony forming units diffusion chamber granulocyte (CFU-dg) and colony forming units culture (CFU-c) in the bone marrow. MGBG treatment led to an increase in CFU-dg alone. Combined treatment seemingly had no effect on marrow stem cells. Total tibial and differential counts were not affected by any of the treatments. Cell proliferation in diffusion chamber cultures, as judged by CFU-dg colony formation, was impaired by MGBG alone or in combination with DFMO, at dose levels which had no effect or increased the precursor cell number in the bone marrow. This effect was partially reversed with either putrescine or spermidine. Determination of intracellular polyamine concentrations, demonstrated decreased putrescine and spermidine levels after DFMO administration. As expected, MGBG treatment resulted in decreased spermidine and spermine levels, concomitant with an increase in putrescine. In mice which received both agents, rather than only MGBG, after 3 days higher intracellular polyamine concentrations were observed. After 11 days, however, there was no significant difference between the two groups.

Effect of lithium on stem cell and stromal cell proliferation in vitro

Lithium is recognized as a potent stimulator of hematopoiesis both in vivo and in vitro. Previous work has suggested that this stimulation is mediated as an indirect, humoral effect by the action of lithium upon the stromal cell population. In the present study, the effects of lithium on the stromal population were investigated using a long-term liquid marrow culture model. These findings indicate that exposure of in vitro cultures to lithium results in an increase in the total cellularity and in the number of various hematopoietic progenitor cells residing within the stromal layer. A distinct morphologically recognizable cell has not been identified as the target cell responsible for the indirect stimulation of hematopoiesis by lithium. However, two candidate radioresistant stromal cells believed to be active in the production of humoral mediators of hematopoiesis did proliferate in response to lithium exposure.

Potentiality of the murine colony-forming cells detected by an in vivo diffusion chamber culture system

Culture of a mixture of bone marrow cells with and without T6 chromosome marker in diffusion chambers in mice yielded colonies (CFU-DG) containing cells of a single karyotype, suggesting clonality. Injection of individual CFU-DG colonies into lethally irradiated mice resulted in increased spleen colony formation on day 12 (CFU-S). The possibility of endogenous origin was excluded by demonstrating the presence of T6 marker in both CFU-DG and CFU-S colonies in karyotypically normal hosts. These findings suggest that the cells giving rise to granulocytic colonies in diffusion chambers also can give rise to multipotential hemopoietic cells.

Distinction of human T-cell line (HUT-102)-derived activity stimulating granulocytic colony formation in diffusion chambers in vivo from activities stimulating erythroid and mixed-colony formation in vitro

Medium conditioned in the presence of human HUT-102 T-cell line cells contains activities stimulating human mixed (colony-forming unit, erythroid, granulocyte, macrophage, megakaryocyte) and erythroid (burst-forming unit, erythroid) colony formation in methylcellulose in vitro and granulocyte colony formation in diffusion chambers in mice. The stimulatory effect of HUT-102-conditioned medium on colony-forming unit, granulocyte diffusion chamber was also observed in diffusion chambers implanted in nude mice. The hemopoietic activities were heat stable and could be detected from serum-free conditioned medium. Chromatographically, it was possible to separate colony-forming unit, granulocyte diffusion chamber-stimulating activity from activities stimulating burst-forming unit, erythroid and colony-forming unit, erythroid, granulocyte, macrophage, megakaryocyte. On the other hand, the latter two activities were indistinguishable by the methodology used in this study. Failure to abolish the hemopoietic activities by boiling or by human T-lymphotropic retrovirus type 1 antibody indicates that human T-lymphotropic retrovirus type 1 or its components potentially present in the conditioned medium were not responsible for the stimulatory effects.

Separation by velocity sedimentation of human haemopoietic precursors forming colonies in vivo and in vitro cultures

Cells which give rise to granulocyte-macrophage colonies under the influence of peripheral blood white cells (CFU-c (WBC] and Mo T cell conditioned medium (CFU-c (Mo] sedimented at a faster rate than the cells which form mixed erythroid-granulocytic colonies in methylcellulose in vitro (CFU-mix) and granulocytic (CFU-dg) and megakaryocytic (CFU-dm) colonies in diffusion chambers in mice. Despite identical peak sedimentation rate for the two CFU-c populations, sedimentation profiles suggest that they are heterogeneous with respect to size. A proportion of CFU-c (Mo) may be identical with CFU-dg and CFU-mix. Sedimentation profiles for cells which give rise to mixed colonies in vitro (CFU-mix) and to granulocytic colonies in diffusion chambers in cyclophosphamide pretreated mice (CFU-dg (CY] and in Mo conditioned medium treated mice (CFU-dg (Mo] were similar. On the average CFU-dm sedimented somewhat slower than CFU-dg. These and other observations suggesting a close relationship between CFU-dg and multipotential haemopoietic precursors are discussed.

Treatment of advanced esthesioneuroblastoma with high-dose chemotherapy and autologous bone marrow transplantation. A case report

A 46-year-old woman presented with an advanced unresectable esthesioneuroblastoma which failed to respond to radiation therapy and one course of chemotherapy. She underwent treatment with high-dose chemotherapy (cyclophosphamide, doxorubicin, and vinblastine) followed by autologous bone marrow transplantation. The major toxicity from the regimen was severe oropharyngeal mucositis. A complete remission was achieved and the patient is free of disease and asymptomatic 3.5 years after treatment.

Granulopoietic precursors in chronic neutropenia

11 patients with chronic neutropenia were evaluated. In 6 patients low numbers of CFU-DG were observed. Only 3 of these patients also had low CFU-C numbers, suggesting that these two precursors are not identical. Bone marrow samples from 2 patients were restudied a year later. The number of CFU-DG remained low while CFU-C numbers increased to control range in 1 patient. Studies for serum inhibitors were negative. No cytogenetic abnormalities were observed. This study suggests that abnormalities at different levels in the haemopoietic precursor cell hierarchy can be detected either simultaneously or independently in patients with chronic neutropenia.

Effect of cooling rate on human and murine hemopoietic precursor cell recovery

The effect of cooling rate on recovery of human and murine hemopoietic precursor cells was studied. In the presence of 10% Me2SO, a cooling rate of 7 degrees C/min from -4 to -30 degrees C was optimal for recovery of both human and murine precursor cells which give rise to colonies in diffusion chambers implanted in mice (CFU-DG). Cooling of human marrow at a rate between 3 and 7 degrees C/min resulted in the best CFU-C recovery, although no good correlation between the cooling rate and murine CFU-C recovery was demonstrated. These data suggest that recovery of the primitive hemopoietic precursor cells can be improved by changing the standard cryopreservation programs used presently. However, improved recovery of CFU-DG does not necessarily translate into faster reconstitution of hemopoiesis. No significant difference was observed in overall recovery of bone marrow cellularity in lethally irradiated mice following injection of untreated marrow and marrow cooled at a rate of 1 and 7 degrees C/min.

The role of polyamine biosynthesis in hematopoietic precursor cell proliferation in mice

Under the influence of a selective irreversible inhibitor of ornithine decarboxylase (ODC), DL-alpha-difluoromethylornithine (DFMO), early hematopoiesis was enhanced. In the bone marrow, the absolute number of cells that give rise to spleen colonies in lethally irradiated mice (CFU-S), granulocytic colonies in diffusion chambers in mice (CFU-DG), and granulocyte-monocyte colonies in agar in vitro (CFU-C) was increased 2-4 fold. This could be abrogated by administration of putrescine, confirming the association of the stimulatory effect with polyamine biosynthesis most likely via depression of ornithine decarboxylase activity and subsequent synthesis of putrescine. Analysis of cell cycle characteristics by 3H-TdR suicide technique demonstrated that the proportion of CFU-S, CFU-DG, and CFU-C in S-phase was significantly increased. Additionally, the stimulatory effect was reflected by enhanced colony formation in diffusion chambers implanted intraperitoneally in mice receiving DFMO. This could also be eliminated by treatment of the host animal with putrescine, again suggesting that polyamine biosynthesis plays an important role at the early stages of hematopoiesis in vivo. Effect of DFMO on colony formation in vitro (CFU-C) was inhibitory and not reversible with putrescine. It could be partially eliminated by aminoguanidine, which neutralizes diamine oxidase present in fetal calf serum used in the CFU-C assay. These data suggest that the effect of DFMO in vitro was nonspecific.

Human T-lymphocyte products stimulate human hemopoietic progenitor cell proliferation in diffusion chambers in vivo

Human myeloid colony formation in diffusion chambers in mice (CFU-DG) was enhanced following administration of a human T-cell-line-derived conditioned medium (Mo). The Mo cell line also elaborates activities stimulating human myeloid colony formation in vitro in agar (CSF) and potentiating erythroid colony formation in vitro in methylcellulose (EPA). Depletion of CSF from Mo conditioned medium by heat inactivation or gel exclusion chromatography did not affect CFU-DG formation. EPA and CFU-DG stimulating activities are heat stable and have approximately the same molecular weight. Culture of human bone marrow cells in diffusion chambers in mice for 4 days under the influence of Mo conditioned medium resulted in significant increment of BFU-E and CFU-DG as judged by subculture of diffusion chamber contents. No effect on CFU-C could be detected.

Corticosteroid effect on murine hemopoietic precursor cells in vivo

The effect of methylprednisolone on murine hemopoietic colony formation in diffusion chambers implanted in mice was evaluated. A dose-dependent increase in granulocytic colony (CFU-DG) formation from murine marrow was observed. This effect could be abrogated by administration of progesterone. These studies suggest that the murine early granulocytic precursors (CFU-DG) have receptors that mediate proliferation-promoting signals triggered by glucocorticoids. Erythroid colony formation (CFU-DE) was not effected by methylprednisolone administration.

Enhancement of murine erythroid colony formation in the presence of activated T lymphocytes

Erythroid colony formation was enhanced by treatment of mouse bone marrow cells with PHA prior to culture in diffusion chambers implanted into intact mice. Addition of PHA-pretreated thymocytes, lymph node lymphocytes, and spleen cells to untreated bone marrow cells also resulted in increased numbers of erythroid colonies in diffusion chambers but had no effect on myeloid colonies. PHA did not augment erythroid colony formation when bone marrow was depleted of Thy 1-bearing cells, although cells capable of erythroid differentiation were still present as judged by the response to erythropoietin. Furthermore, mixing of bone marrow depleted of Thy 1 + cells with PHA-treated thymocytes restored augmented erythroid colony formation. Lack of responsiveness of bone marrow cells to concanavalin A and pokeweed mitogen may indicate that a specific T cell subpopulation reacting with PHA is able to stimulate erythropoiesis. Note that addition of untreated thymocytes, lymph node lymphocytes, and spleen cells into cultures had no effect.

Differentiation of subpopulations of human and murine hemopoietic stem cells by hypotonic lysis

Both human and mouse bone marrow contain subpopulations of hemopoietic stem cells that greatly vary in their resistance to water exposure: The cells forming erythroid colonies or bursts in methyl cellulose in vitro are most sensitive to hypotonic conditions and are destroyed within 60 s in the hypotonic milieu. The murine pluripotent stem cells assayed by the spleen colony technique, as well as both murine and human myeloid stem cells assayed by the plasma clot diffusion chamber technique, displayed intermediate sensitivity and were nearly completely eliminated by 120 s of exposure to water. Both human and mouse bone marrow stem cells producing myeloid colonies in agar are most resistant to hypotonic conditions. The addition of monocyte-macrophages and lymphoid cells to water-exposed mouse bone marrow cell populations to compensate for losses did not restore either erythroid or myeloid colony formation.

Hemopoietic precursor cells in human peripheral blood

Human peripheral blood contains two types of stem cells that differentiate along the granulocytic pathway. They are separable by their ability to form colonies in agar in vitro (CFU-C) and in plasma clots in diffusion chambers in vivo (CFU-DG). Kinetic studies suggest that CFU-DG represents an intermediate between the still hypothetical human pluripotent stem cell and CFU-C.