Biomedical subjects
Publications and source records attributed to M Fukuda.
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Local injections of interferon, 30 X 10(4) IU, ten times, were found to reduce masses of neuroblastoma. Histologic findings and nuclear DNA measurements of cells from tumors in which interferon has been injected compared with cells from tumors that did not receive injections demonstrated that the reduction of neuroblastoma masses by interferon did not depend on increased cell differentiation or on interruption of tumor cell production. Although the mechanism of interferon's action on reducing neuroblastoma is unknown, the disappearance of tumor cells may be caused by high levels of interferon in tumor tissues.
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The distribution of substance P (SP)-like immunoreactivity in the rat retina was investigated by immunohistochemistry. SP-positive cells were found throughout the retina. The majority of them were located in the proximal portion of the inner nuclear layer and the processes from these cells directed to the inner plexiform layer where they ramified, suggesting that SP-positive cells located in this region probably are amacrine cells. Few SP-positive cells were seen within the ganglion cell layer. They were considered displaced amacrine cells.
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Although suppressor cells appear to be involved in the normal regulatory mechanism of the lymphoid system, they are also considered to have a role in the immunosuppression of certain malignancies. Suppressor activity of lymphocytes can be reproducibly measured by use of the mixed lymphocyte culture-mitogen interaction (MLC-M) in which the stimulating cell either is in the basal state or has been induced by Concanavalin A. This yields a quantitative measure of resting suppressor cell activity as well as the maximum generation of suppressor activity as induced by Con A. This test was performed, using autologous and allogenic cell combinations in a group of 13 cancer patients and 18 normal controls. Normal lymphocytes activated by Con A in 48-hour lymphocyte cultures significantly decreased the mitogenic response of lymphocytes from healthy, male donors to phytohemagglutinin (PHA), Con A, and Pokeweed mitogen (PWM) in both autologous and homologous systems. In contrast, Con A activated lymphocytes from cancer patients demonstrated diminished suppressor activity compared with controls in autologous (P less than 0.01), and allogenic (P less than 0.005) systems. There was a correlation between the degree of immunosuppression and suppressor cell activation: i.e., the patients most depressed generally had the lowest suppressor cell activation. Untreated lymphocytes from cancer patients also exerted suppressive effects on normal lymphocyte responses, suggesting an increased resting level of suppressor cells. These data suggest that in addition to having depressed cellular immune responses, cancer patients frequently have reduced capability to generate suppressor cell activity, which implies a generalized defect in this aspect of immune regulation.
Gangliosides were isolated from purified preparations of human peripheral blood lymphocytes and neutrophils. Structural analyses and comparisons were performed by direct probe mass spectrometry and by degradation studies with the following enzymes: Escherichia freundii endo-beta-galactosidase; Clostridium perfringens and Arthrobacter ureafaciens neuraminidase; and jack bean beta-N-acetylhexosaminidase and beta-galactosidase. This combination of techniques allowed us to obtain carbohydrate composition and sequence information without the aid of methylation or carbohydrate compositional analyses using only 1-2 mg of purified gangliosides. On the basis of these studies we propose that human lymphocytes and neutrophils have gangliosides with the following structures. NeuAc alpha 2 leads to 3Gal beta 1 leads to 4Glc beta 1 leads to 1Cer Structure A NeuAc alpha 2 leads to ? GlcNAc beta 1 leads to 3Gal beta 1 leads to 4Glc beta 1 leads to 1Cer Structure B NeuAc alpha 2 leads to ? Gal beta 1 leads to 3,4GlcNAc beta 1 leads to 3Gal beta 1 leads to 4Glc beta 1 leads to 1Cer Structure C All three compounds were isolated from both cell types with structure A being the major lymphocyte ganglioside and structure C the major neutrophil ganglioside. Structure B is a novel ganglioside and may represent a leukocyte-specific glycosphingolipid. Neuraminidase degradation studies demonstrated that only one ganglioside species of each cell type contains an internally linked sialic acid residue, and on the basis of thin layer chromatographic analysis this component is the same as the major brain ganglioside, GM1 (II3-N-acetylneuraminosyl-gangliotetraosylceramide). In addition, large gangliosides with the general structure NeuAc alpha 2 leads to ?(Gal beta 1 leads to 3,4GlcNAc beta 1 leads to 3)n Gal beta 1 leads to 4Glc beta 1 leads to 1Cer were isolated. These results are discussed as they relate to blood group antigens and specific cell surface markers in human leukocytes.
Unit activity of 144 lateral hypothalamus (LHA) neurons was analyzed in monkey during bar pressing feeding behavior. Eighteen neurons responded only when the animal saw food, and 23 responded only during ingestion of food. Ten responded at both the sight of food and throughout the bar pressing and ingestion periods, even in high fixed ratio schedules. Three neurons responded, not at the sight of food, but at the sight of non-food. Nineteen out of a total of 54 of the above responding neurons were studied for response to differences between food and non-food. Eight responded similarly at the sight of both food and non-food, while 11 responded differently. Responses during the ingestion period were strong and lasted longer than 5--10 sec. The data indicate that some LHA neurons are involved in the discrimination of food, the drive to obtain it and the perception of reward.
Unit activity and changes during bar press feeding behavior after presentation of food or non-food were analyzed in 198 neurons in the head of the caudate nucleus of monkey. Eight neurons responded uniquely at the sight of food. The degree of the food-specific responses differed depending on the nature of the food and the hunger-satiation state. On the other hand, 17 neurons responded more or less to the sight of food and during bar pressing for food. These two types of neuron seem to be important to bar pressing feeding behavior, which consists of recognition of food and a bar press task to obtain food.
Erythrocyte surface glycoproteins from patients with various types of sickle cell anemia have been analyzed and compared with those from normal individuals. By hemagglutination with various anti-carbohydrate antibodies, sickle cells showed profound increase of i antigens and moderate increase of GlcNAc beta 1 leads to 3Gal beta 1 leads to 3 Glc structure, whereas antigenicity toward globosidic structure was unchanged. In parallel to these findings, erythrocytes of sickle cell patients have additional sialylated lactosaminoglycan in Band 3. Thus, it can be concluded that erythrocytes of sickle cell patients are characterized by an altered cell surface structure which does not appear to be due to topographical changes of cell surface membrane. It is possible that the anemia or the "stress" hematopoiesis in these patients is responsible for these changes.
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A technique for isolation of cells from paraffin embedded tissue is indispensable for the performance of Feulgen-DNA cytofluorometry in parallel with the definition of histological characteristics. Background fluorescence due to nonspecific dye-binding by a "pseudo-plasmal reaction" is usually found to be so intense on cells isolated from formalin-fixed tissues, that we are often forced to abandon quantitative DNA determinations. In the present work, we report the fixation of tissues with Carnoy's fixative for 12 h at 5 degrees C not only reduces nonspecific dye-binding but also facilitates the process of cell isolation. Furthermore, we find that pre-treatment of cells isolated from Carnoy-fixed tissues with acidic azocarmin G solution completely blocks nonspecific dye-binding in subsequent acriflavine Feulgen nuclear staining. This combination of techniques for specimen preparation enables us to carry out Feulgen-DNA cytofluorometry on cells isolated from histological sections with satisfactorily low coefficients of variation (less than 8%). The techniques should be widely applicable for parallel DNA determinations and histology.
A method is described for the production of rabbit anti-Gm sera using normal IgG proteins and fragments thereof as the immunogens. Anti-G3m(16) and anti-G3m(21) were readily producible by immunizations with protein A-purified IgG3 proteins of G3m(13, 15, 16) and G3m(21) type, respectively. Anti-G1m(2), anti-G1m(3), and anti-G3m(5) were obtained by immunizations with type Gm(1, 2, 21) Fc fragments, type Gm(1, 3, 5, 13) IgG1-rich IgG, and type G3m(5, 13, 21) IgG3, respectively. These immune sera can distinguish the 9 Gm phenotypes in the Japanese.
Lateral hypothalamus activity was observed in 23 single units for more than 24 h each in freely moving rats. The activity of 3 neurons was circadian related: low in the day and high at night. Ten neurons responded with inhibition related to individual feeding acts. These two neuron types might be important for long-term feeding rhythm and short-term feeding behavior.
Cell surface glycoprotein structures of human leukemic cell lines blocked at various stages of myeloid (granulocyte--monocyte) differentiation and maturation were characterized. Cell lines representing early stages of differentiation and maturation such as KG1a, KG1 and those representing later stages such as ML-1-3 and HL-60 were found to express discretely different sets of cell surface glycoproteins. The proteins (such as Gp130) present on mature granulocytes appear only in cell lines representing later stages of maturation. The quantity and structure of the carbohydrate chains susceptible to endo-beta-galactosidase ("lactosaminoglycan") are also significantly different among cell lines. A small quantity of essentially unbranched lactosaminoglycan is present on KG1a and KG1 cells, whereas a significant quantity of branched lactosaminoglycan is present on the more mature ML-1-3 and HL-60 cells. The process of myeloid maturation from promyeloblast to granulocyte is accompanied by the disappearance of the 105- and 95-kilodalton glycoproteins, the appearance of Gp130, and a great increase in the quantity and branching structure of lactosaminoglycan. These results are discussed together with our previous findings on erythroid differentiation and maturation.
The initiation site for reconstitution on genome RNA was determined by electron microscopic serology for a watermelon strain of cucumber green mottle mosaic virus (CGMMV-W), which is chemically and serologically related to tobacco mosaic virus (TMV). The initiation site was located at the same position as that of the cowpea strain, a virus that produces short rods of encapsidated subgenomic messenger RNA for the coat protein (a two-component TMV), being about 320 nucleotides away from the 3' terminus, and hence within the coat protein cistron. Although CGMMV-W was until now believed to be a single-component TMV, the location of the initiation site indicated the presence of short rods containing coat protein messenger RNA in CGMMV-W-infected tissue, as in the case for the cowpea strain. We found such short rods in CGMMV-W-infected tissue. The results confirmed our previous hypothesis that the site of the initiation region for reconstitution determines the rod multiplicity of TMV. The finding of the second two-component TMV, CGMMV, indicates that the cowpea strain of TMV is not unique in being a two-component virus and that the location of the assembly initiation site on the genome RNA can be a criterion for grouping of viruses.
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