ISOLATION, CHARACTERIZATION, AND DISTRIBUTION OF ACID MUCOPOLYSACCHARIDES IN RABBIT LEUCOCYTES

Proteoglycans in haemopoietic cells

Proteoglycans are produced by all types of haemopoietic cells including mature cells and the undifferentiated stem cells. The proteinase-resistant secretory granule proteoglycan (serglycin; Ref. 14), is the most prevalent and best characterised of these proteoglycans. Although its complete pattern of distribution in the haemopoietic system is unknown, serglycin has been identified in the mast cells, basophils and NK cells, in which secretion is regulated, and in HL-60 cells and a monocytoid cell line (Kolset, S.O., unpublished data) in which secretion is constitutive. Proteinase-resistant proteoglycans have been detected in human T-lymphocytes and murine stem cells (FDCP-mix) and the core proteins may be closely related to serglycin. A variety of glycosaminoglycan chains are assembled on the serglycin protein and it is likely that this class of proteoglycan can carry out a wide variety of functions in haemopoietic cells including the regulation of immune responses, inflammatory reactions and blood coagulation. There is strong evidence that in mast cells, NK cells and platelets, the proteoglycans are complexed to basic proteins (including enzymes and cytolytic agents) and amines in secretory granules and such complexes may dissociate following secretion from the cell. The stability of the complexes may be regulated by the ambient pH which may be acidic in the granules and neutral or above in the external medium. However, proteinase-proteoglycan complexes in mast cell granules seem to remain stable after secretion and it has been proposed that the proteoglycan regulates activity of proteinases released into the pericellular domain. The functions of proteoglycans which are constitutively secreted from cells are less clear. If cells have no requirement for storage of basic proteins why do they utilise the same design of proteoglycan as cells which accumulate secretory material prior to regulated release? We should stress that the so-called constitutive secretory pathway has been identified in haemopoietic cells in culture, which are usually maintained and grown in the presence of mitogenic factors (e.g., IL-2, IL-3). the cells are therefore activated and it has not been established that continuous proteoglycan secretion occurs in quiescent cells circulating in the peripheral blood. It is possible that lymphocytes, monocytes and macrophages, in which the constitutive secretion pathway operates in vitro, may store proteoglycan in vivo unless stimulated by mitogens or other activating agents.(ABSTRACT TRUNCATED AT 400 WORDS)

Microwave-stimulated staining of plastic embedded bone marrow sections with the Romanowsky-Giemsa stain: improved staining patterns

Staining plastic sections with the Romanowsky-Giemsa method is both time-consuming and difficult. This paper reports how the staining time can be reduced to 25 min using microwave irradiation of the staining solution. It is shown that staining results depend on the fixative used, staining temperature, dye concentration and pH of the staining solution as well as on several parameters of the microwave irradiation technique. The staining patterns are improved when compared with those obtained by conventional staining of plastic sections. The colors are more brilliant and greater contrasts are observed. Basophilia, polychromasia, and orthochromasia accompanying red cell maturation are more pronounced. For white cell maturation the initial appearance of specific granules (neutrophil, basophil, and eosinophil) is more evident. Thus, cell classification is easily accomplished using the described technique. It is suggested that microwave-stimulated staining be considered for routine use.

Glycosaminoglycans in human salivary-duct stones

These were demonstrated using histochemical and biochemical techniques. The presence of hyaluronic acid and chondroitin sulphate was confirmed by enzymic digestion. These substances may arise from inflammation in peri-ductal tissue.

Understanding Romanowsky staining. I: The Romanowsky-Giemsa effect in blood smears

Normal blood smears were stained by the standardised azure B-eosin Y Romanowsky procedure recently introduced by the ICSH, and the classical picture resulted. The effects of varying the times and temperature of staining, the composition of the solvent (buffer concentration, methanol content, & pH), the concentration of the dyes, and the mode of fixation were studied. The results are best understood in terms of the following staining mechanism. Initial colouration involves simple acid and basic dyeing. Eosin yields red erythrocytes and eosinophil granules. Azure B very rapidly gives rise to blue stained chromatin, neutrophil specific granules, platelets and ribosome-rich cytoplasms; also to violet basophil granules. Subsequently the azure B in certain structures combines with eosin to give purple azure B-eosin complexes, leaving other structures with their initial colours. The selectivity of complex formation is controlled by rate of entry of eosin into azure B stained structures. Only faster staining structures (i.e. chromatin, neutrophil specific granules, and platelets) permit formation of the purple complex in the standard method. This staining mechanism illuminates scientific problems (e.g. the nature of 'toxic' granules) and assists technical trouble-shooting (e.g. why nuclei sometimes stain blue, not purple).

On the nature of Romanowsky--Giemsa staining and its significance for cytochemistry and histochemistry: an overall view

The chances of Romanowsky---Giemsa (RG) staining becoming a reliable and useful histochemical procedure are reviewed, based on the now proven fact that RG staining requires two dyes only, namely, cationic Azure B and anionic Eosin Y. These two dyes differ from otherwise similar dye combinations in that they give, on distinct biological substrates, one additional colour, purple, which cannot be obtained by the use of either dye alone. The purple colour characterizes the Romanowsky--Giemsa effect (RGE), which is the essential feature of RG staining. Consideration is given to the physico-chemical and morphological implications of RGE. Of primary importance is the nature of the biological substrates where RGE occurs, and also of those where it has never been observed. The way substrates react to RG stains largely depends on the kind of pretreatment they have received; for instance, alcoholic fixation preserves RGE but formaldehyde may inhibit it. Physico-chemical factors are considered which, by altering either the biological substrates or the composition of the staining solutions, may modify the RG staining pattern. This review also serves as an introduction for a series of experimental papers that will follow and which are intended to consolidate the basis of RG staining, a method which holds much promise as a useful histochemical tool.

Ultrastructural visualization of complex carbohydrates in eosinophilic leukocytes

Complex carbohydrates in eosinophils from human, rabbit, and rat marrow were identified and localized by cytochemical and radioautographic methods. The high iron diamine-thiocarbohydrazide-silver proteinate (HID-TCH-SP), low iron diamine (LID)-TCH-SP, and periodate (PA)-TCH-SP methods were used for the localization of sulfate, sulfate and carboxyl, and vicinal glycol- containing complex carbohydrates, respectively. Golgi vesicles and small precursor granules (0.2-0.4 micrometer in diameter) demonstrated strong HID-TCH-SP staining and labeled intensely after a 10-minute pulse with 35SO4(2). Crystalloid-free or immature specific granules (0.5-0.9 micrometers in diameter) labeled heavily after a 60-minute incubation and 60-minute chase with 35SO4(2). Immature granules were graded according to their HID-TCH-SP staining. Type I granules demonstrated strong rim staining and similar or somewhat less central staining, whereas type 2 granules only demonstrated rim staining, and type 3 granules lacked staining. Fully mature crystalloid-containing granules lacked staining. LID-TCH-SP similarly stained the HID-positive sulfated material in cytoplasmic granules. PA-TCH-SP stained some Golgi vesicles and diffusely stained all precursor granules and type 1 granules. Weaker staining was observed in type 2 granules and staining was very weak or absent in type 3 and crystalloid-containing granules. In early eosinophils, tubulovesicular structures (TVS) were observed rosetting and contacting precursor and type 1 granules. These TVS contained material with strong PA-TCH-SP staining but lacked HID-TCH-SP or LID-TCH-SP-reactive acidic glycoconjugates. Flattened Golgi saccules or early eosinophils stained weakly or not at all with the PA-TCH-SP method. Small granules and TVS in late (bilobed) eosinophils displayed PA-TCH-SP reactivity and lacked HID-TCH-SP staining but differed from TVS in early eosinophils in that they were not associated as rosettes with specific granules. These results indicate that sulfated and vicinal glycol-containing complex carbohydrates are differently disturbed in immature specific granules of eosinophils and presumably become masked to staining as the granule matures.

Cytochemical investigation of neutral proteases in polymorphonuclear (PMN) neutrophils in acute inflammatory diseases

Neutral proteases can be released from PMN neutrophils in blood smears from healthy subjects by incubation with NaCl-borate buffer. The activity of the PMN proteases can be revealed by the degradation of erythrocytes and plasma within ring-shaped areas centered around each neutrophil (halo effect). During the acute stage of various inflammatory diseases (pneumonia, meningitis, cholecystitis, etc.) the activity of neutral PMN proteases is substantially reduced, as reflected by reduced halo formation. After recovery, halo formation returns to normal. Temporary lowering of neutral PMN proteases is thus one of a series of functional defects of PMN neutrophils which are detectable in the course of acute infectious diseases. These include reduced phagocytosis, altered chemotaxis and reduced bactericidal function. The cytochemical test for neutrophilic granulocyte function used in the present investigation is especially practical by comparison with the other techniques: it saves time and is simple to perform.

Lysosomal composition in cultured vascular smooth muscle cells: electron probe analysis

Spherical electron-dense organelles in the perinuclear region of cultured guinea pig aortic smooth muscle cells were identified as lysosomes by their ability to accumulate acridine orange and by cytochemical demonstration of their acid phosphatase content. The number and size of lysosomes increased in subcultured cells. The elemental composition of the lysosomes was quantitated by electron probe analysis of whole freeze-dried cells and of cryosections. In lysosomes at this stage in their development, the sulfur concentration was higher than that in the cytoplasm and the K/Na concentration ratio was similar to that in the cytoplasm.

Mucosubstances of rabbit granulocytes studied by means of electron-microscopic radioautography and X-ray microanalysis

Rabbit bone marrow cells have been studied by means of light- and electron-microscopic radioautography and X-ray microanalysis. Carrier free sulfuric acid was used as the radioactive precursor in this experiment. Immature granulocytes showed more active incorporation than mature ones. Silver grains were observed in the Golgi apparatus and granules in three kinds of granulocytes. Electron-microscopically, immature granules showed the incorporation of inorganic sulfate, while mature ones did not. Sulfur was detected in all kinds of granules of the three granulocyte types by X-ray microanalysis. It is concluded that incorporated inorganic sulfur may be utilized for the synthesis of acid glycosaminoglycans and the sulfur detected by X-ray microanalysis may be that contained in the acid glycosaminoglycan. The sulfur detected in the specific granules of the heterophil probably derives from proteins or polypeptides incorporating sulfur containing amino acids.

[Demonstration of neutrophil leukocytes on blood smears by a modified colloidal iron reaction (author's transl)]

Using a modified colloidal iron reaction two positively reacting components in neutrophil leukocytes are discernible: 1. In neutrophils of unfixed smears the outer membrane or surface coat is stained. 2. After fixation with buffered formalin, formalin-sublimate or Helly's fluid a strongly reacting cytoplasmic component is demonstrable. After fixation with formalin-sublimate or Helly's fluid the latter has been proven to be sensitive against treatment with sialidase thus indicating the presence of sialic acid residues in neutrophil granulocytes.

Urinary excretion of glycosaminoglycans in disseminated neoplasm

Urinary glycosaminoglycan excretion was studied in 24 cases of disseminated neoplasm, 12 of which had unequivocal evidence of skeletal involvement. Urinary hydroxyproline, cetylpyridinium chloride (CPC)-precipitable uronic acid, and CPC-precipitable hexosamine were expressed as a ratio to urinary creatinine. Glycosaminoglycans contained in urine concentrated x 1000 by vacuum-dialysis were separated by electrophoresis on cellulose acetate and stained with alcian blue. Of the 12 cases with clear evidence of skeletal involvement, eight (66%) showed elevation of serum alkaline phosphatase, five (42%) showed elevation of urinary hydroxyproline, and three (25%) showed elevation of urinary uronic acid. It is concluded that urinary uronic acid is not a sensitive index of skeletal involvement in disseminated neoplasm. The most striking feature of the study was the identification of a well-defined fraction indist inguishable from hyaluronic acid in seven (58%) of the cases with evidence of skeletal involvement. Hyaluronic acid is not normally identifiable in adult human urine. The hyaluronic acid excretors showed more consistent biochemical evidence of bone disease (elevation of serum alkaline phosphatase and urinary hydroxyproline) than the non-excretors. The possibility that the urinary hyaluronic acid is derived from degradation of skeletal hyaluronic acid is discussed. An alternative explanation is that the hyaluronic acid is derived from neoplastic cells as part of a reversion of glycosaminoglycan synthesis to a more ;fetal' state, a glycosaminoglycan counterpart of the production of oncofetal antigens by neoplastic cells.

Hyaluronic acid in supragingival dental calculus

A method is described for the isolation of heteropolysaccharides from human supragingival calculus. One component was identified as hyaluronic acid, by electrophoretic mobility, testicular hyaluronidase digestion and cetylpyridinium chloride profiles. No sulphated glycosaminoglycans were detected.

Inhibition of leucocytic lysosomal enzymes by glycosaminoglycans in vitro

1. A lysosomal fraction was separated by density-gradient centrifugation from a highly purified human polymorphonuclear leucocyte suspension. 2. Some 23 different lysosomal enzymes were assayed for activity in the presence of various concentrations of glycosaminoglycans. 3. The 21 acid hydrolases assayed were strongly inhibited to different degrees by low (0-12 mmol/l) concentrations of glycosaminoglycans in a pH-dependent manner. Thus inhibitions were stronger below pH4.5, with activity returning to control values at about pH5.0. 4. On a molar basis, the inhibitory activity for the several glycosaminoglycans studied was: heparin greater than chondroitin sulphate greater than hyaluronic acid. 5. Once the glycosaminoglycan-acid hydrolase complex was formed, it was partially dissociated by slight elevations in the pH of the incubation medium, by increasing the ionic strength of the incubation medium, or by adding several cationic proteins (e.g. histone, protamine). 6. As leucocytic lysosomes contain large amounts of chondroitin sulphate, and have a strongly acid intragranular pH, we suggest that glycosaminoglycans may modify lysosomal function through the formation of complexes with lysosomal enzymes, by inhibiting the digestive activity of the acid hydrolases when the intralysosomal pH is below their pI.

Activation of lysosomal enzymes in polymorphonuclear leukocytic granules: the role of phospholipid-protein interaction

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Characterization of a neutral protease from lysosomes of rabbit polymorphonuclear leucocytes

1. The subcellular distribution has been investigated of a protease from rabbit polymorphonuclear leucocytes, obtained from peritoneal exudates. The enzyme, optimally active between pH7.0 and 7.5, hydrolyses histone but not haemoglobin, sediments almost exclusively with a granule fraction rich in other lysosomal enzymes, and is latent until the granules are disrupted by various means. 2. Enzymic analysis of specific and azurophilic granules separated by zonal centrifugation showed that neutral protease activity was confined to fractions rich in enzymes characteristic of azurophile granules. 3. Recovery of neutral protease activity from subcellular fractions was several times greater than that found in whole cells. This finding was explained by the presence of a potent inhibitor of the enzyme activity in the cytoplasm. 4. The effect of the inhibitor was reversed by increasing ionic strength (up to 2.5m-potassium chloride) and by polyanions such as heparin and dextran sulphate, but not by an uncharged polymer, dextran. 5. The enzyme was also inhibited, to a lesser extent, by 1-chloro-4-phenyl-3-l-toluene-p-sulphonamidobutan-2-one, soya-bean trypsin inhibitor and in-aminohexanoate (in-aminocaproate). 6. The granule fractions failed to hydrolyse artificial substrates for trypsin and chymotrypsin. 7. Partial separation of the enzyme was achieved by Sephadex gel filtration at high ionic strength and by isoelectric focusing. The partially separated, activated enzyme showed an approximately 300-fold increase in specific activity over that in whole cells.

Ultrastructural localization of dialyzed iron-reactive mucosubstance in rabbit heterophils, basophils, and eosinophils

For ultrastructural localization of acid mucosubstances in rabbit granulocytes, bone marrow and buffy coat specimens were fixed with formalin, glutaraldehyde, or osmium tetroxide, sectioned at 40 micro, and stained with the Rinehart and Abul-Haj solution of dialyzed iron (DI). Heterophils revealed DI staining on the outer surface of the plasma membrane, in the Golgi complex involved in primary granulogenesis, and in primary granules. The intragranular distribution of DI-stained material varied at different stages in the maturation of primary granules. Immature granules of heterophils fixed by any of the three methods contained a peripheral concentric band of DI-positive material; however, fully mature primary granules possessed a core of DI-reactive material in heterophils fixed with osmium tetroxide, but they contained little or no staining in heterophils fixed with formalin or glutaraldehyde. Secondary granules of rabbit heterophils failed to stain with DI. Tertiary granules, observed only in late heterophils, contained distinct DI-positive particles. Basophil granules exhibited intensely DI-stained material distributed in an orderly pattern throughout the granule. In eosinophils, DI staining was localized in the Golgi complex and in the rims of a few immature cytoplasmic granules.

Origin of granules in polymorphonuclear leukocytes. Two types derived from opposite faces of the Golgi complex in developing granulocytes

The origin, nature, and distribution of polymorphonuclear leukocyte (PMN) granules were investigated by examining developing granulocytes from normal rabbit bone marrow which had been fixed in glutaraldehyde and postfixed in OsO(4). Two distinct types of granules, azurophil and specific, were distinguished on the basis of their differences in size, density, and time and mode of origin. Both types are produced by the Golgi complex, but they are formed at different stages of maturation and originate from different faces of the Golgi complex. Azurophil granules are larger ( approximately 800 mmicro) and more dense. They are formed only during the progranulocyte stage and arise from the proximal or concave face of the Golgi complex by budding and subsequent aggregation of vacuoles with a dense core. Smaller ( approximately 500 mmicro), less dense specific granules are formed during the myelocyte stage; they arise from the distal or convex face of the Golgi complex by pinching-off and confluence of vesicles which have a finely granular content. Only azurophil granules are found in progranulocytes, but in mature PMN relatively few (10 to 20%) azurophils are seen and most (80 to 90%) of the granules present are of the specific type. The results indicate that inversion of the azurophil/specific granule ratio occurs during the myelocyte stage and is due to: (a) reduction of azurophil granules by multiple mitoses; (b) lack of new azurophil granule formation after the progranulocyte stage; and (c) continuing specific granule production. The findings demonstrate the existence of two distinct granule types in normal rabbit PMN and their separate origins from the Golgi complex. The implications of the observations are discussed in relationship to previous morphological and cytochemical studies on PMN granules and to such questions as the source of primary lysosomes and the concept of polarity within the Golgi complex.