Distribution Of Acid Phosphatase Research Articles

Growth hormone receptor and insulin-like growth factor-I immunoreactivity in osteoclast-like cells during tooth eruption in the toothless (osteopetrotic) rat following treatment with colony-stimulating factor-1.

In the toothless (tl/tl) osteopetrotic rat, teeth form but fail to erupt. Treatment of tl/tl rats with colony-stimulating factor-1 (CSF-1) activates bone resorption by osteoclasts, permits tooth eruption, and up-regulates the immunoreactivity of bone marrow mononuclear cells to growth hormone receptor (GHr) and insulin-like growth factor (IGF)-I. This study examined the distribution of tartrate-resistant acid phosphatase (TRAP) and immunoreactivity for GHr and IGF-I in osteoclast-like cells located on the alveolar bone margin, adjacent to the lower first molar crown, in 14-day-old normal and tl/tl rats, following treatment with CSF-1. Osteoclast-like cells demonstrated a positive reaction for TRAP, GHr, and IGF-I in all groups. However, in tl/tl tissue, osteoclast-like cells were generally negative for GHr. There was no significant difference in the total number of TRAP-, GHr-, and IGF-I-positive osteoclast-like cells on the adjacent bone margin in normal, normal treated with CSF-1, and tl/tl rats. CSF-1 treatment of the tl/tl rat significantly increased the total number of osteoclast-like cells, which were positive for TRAP (p < 0.001), GHr (p < 0.05) and IGF-I (p < 0.01).

Expression and distribution of tartrate-resistant purple acid phosphatase in the rat nervous system.

Tartrate-resistant purple acid phosphatase (TRAP) of osteoclasts and certain cells of the monocyte-macrophage lineage belongs to the family of purple acid phosphatases (PAPs). We provide here evidence for TRAP/PAP expression in the central and peripheral nervous systems in the rat. TRAP/PAP protein was partially purified and characterized from the trigeminal ganglion, brain, and spinal cord. The TRAP activity (U/mg tissue) in these tissues was about 10-20 times lower than in bone. Reducing agents, e.g. ascorbate and ferric iron, increased the TRAP activity from the neural tissues (nTRAP) and addition of oxidizing agents completely inactivated both bone and nTRAP. The IC(50) for three known oxyanion inhibitors of TRAP/PAP was similar for bone and nTRAP with the same rank order of potency (molybdate > tungstate > phosphate). This indicates that the redox-sensitive binuclear iron center characteristic of mammalian PAPs is present also in nTRAP. Western blots of partially purified nTRAP revealed a band with the expected size of 35 kD. The expression of TRAP in the trigeminal ganglion, brain, and spinal cord was confirmed at the mRNA level by RT-PCR. In situ hybridization histochemistry demonstrated TRAP mRNA expression in small ganglion cells of the trigeminal ganglion, in alpha-motor neurons of the ventral spinal cord, and in Purkinje cells of the cerebellum. TRAP-like immunoreactivity was encountered in the cytoplasm of neuronal cell bodies in specific areas of both the central and the peripheral nervous system. Together, the data demonstrate that active TRAP/PAP is expressed in certain parts of the rat nervous system.

Distribution of acid phosphatases in the hypopharyngeal glands from workers, queens and males of a Brazilian stingless bee Scaptotrigona postica Latreille: an ultrastructural cytochemical study.

The present study reports the localization of acid phosphatase in the hypopharyngeal gland cells from workers (newly-emerged, nurse and forager), queens (newly-emerged and laying) and males (newly-emerged and mature for mating) of the Brazilian stingless bee, Scaptotrigona postica. The phosphatase activity varied in intensity and localization depending on the individual class, physiological age and the substrate used. In newly-emerged workers, the phosphatase-positive sites suggest the involvement of the enzyme with cellular differentiation that occurs in the presecretory phase, in nurse workers with protein synthesis and in forager workers with changes in cellular activity or glandular regression. In males mature for mating and laying queens, the positive sites are related to secretory activity, showing that the gland maintains some activity in spite of the regressive aspect. Of the substrates used, beta-glycerophosphate gave the least specific localization.

Characterization of Acid Phosphatase Activities in the Equine Pathogen Streptococcus equi

Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts. The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis. To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resistant to EDTA. Western blotting with a polyclonal anti-LppC antiserum revealed the presence of a cross-reactive 32 kDa protein in both organisms. The cross-reactive protein in S. equi was shown to be a surface accessible lipoprotein as its processing was inhibited by the antibiotic globomycin and it was released from whole cells by treatment with trypsin. The presence of DNA sequences homologous to the S. equisimilis lppC gene were confirmed by PCR. These data strongly suggest that Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus produce a lipoprotein acid phosphatase homologous to LppC of S. equisimilis.

Distribution of exudates of lupin roots in the rhizosphere under phosphorus deficient conditions

The distribution of secretory acid phosphatase and organic acids enhanced by phosphorus deficiency in lupin rhizosphere was investigated using a rhizobox system which separated the rhizosphere soil into 0.5 mm fractions. In the soil fraction closest to the root surface, the lupin exudates displayed an acid phosphatase activity of 0.73 u g−1 dry soil and citrate concentration of 85.2 μmol g−1 dry soil, respectively. The increase of the acid phosphatase activity-induced an appreciable depletion of organic P in the rhizosphere, indicating that lupin efficiently utilized the organic P from soil through the enzyme activitye The sterile treatments demonstrated that the acid phosphatase in the rhizosphere was mainly derived from lupin root secretions. The secretory organic acids enhanced considerably the solubility of the inorganic P in three types of soil and a sludge. However, the secretory acid phosphatase and organic acids from lupin roots were only detected in a considerable amount in 0-2.5 mm soil fractions from root surface.

The epididymis of the prepubertal swamp buffalo (Bubalus bubalis): histochemistry of phosphatases.

The distribution of phosphatases was examined in the epididymis of swamp buffaloes aged 1.5-2 years, where spermatogenic activity in the testis had reached the early primary spermatocyte stage. A granular distribution of acid phosphatase was present in the luminal region of the epithelium of the efferent ductules. In the ductus epididymidis, four zones were identified and all zones showed varying degrees of acid-phosphatase activity in the epithelium, with the most pronounced activity in the apical region and stereocilia of zone II. Alkaline-phosphatase activity occurred along the basal region of the epithelium in zones I, III and IV of the ductus and in the stereocilia of zones I and II. An intense apical reaction was seen in zone II. The efferent ducts were free of this enzyme. Thus, zone II is considered the most active region, having the function of absorption and possibly steroid metabolism.

Cytochemical study of the germinal membrane of the Echinococcus granulosus cyst

The present cytochemical study was undertaken to provide more information on the localization of enzymatic and glycoconjugates in the germinal membrane of the Echinococcus granulosus cyst. The distinctive distribution of binding sites for two lectins (peanut agglutinin and Dilochos biflorus agglutinin) in the germinal membrane are described. An investigation is made of the distribution and specific activity of adenosine triphhosphate, alkaline phosphatase and acid phosphatase. The results suggest that cells located in the deeper layer of the germinal membrane are intrinsic in the cellular differentiation process. The dissimilares detected in both the enzymatic activity and the lectin-binding receptors could be associated with metacestode development or degeneration.

Acid phosphatase activity in hemolymph of the migratory grasshopper, Melanoplus sanguinipes, during Beauveria bassiana infection

AbstractThe distribution and abundance of acid phosphatase (AP) in hemolymph (HL), plasma (PM) and hemocyte lysate supernatant (HLS) of the migratory grasshopper, Melanoplus sanguinipes infected with Beauveria bassiana (strain GK 2016) has been examined. AP activity was determined at intervals from 30 min to 60 h postinjection of 2 μl of 1 times 108conidia/ml per grasshopper. The enzyme was detected with the substrate β‐glycerophosphate in sodium acetate acetic acid buffer form hemocytes (HC) and with p‐nitrophenol phosphate sodium salt for HL, PM and HLS. In results of experiment 1 proportion of HC showing AP activity increased 1–2 h, then returned to normal after 4 h. However, in B. bassiana‐injected grasshoppers, a second increase was noted 24 h later which was not seen in the Tween‐80‐injected insects. Uninjected controls showed no change with time in the proportion of HC with AP activity.Studies were also made of the distribution of AP activity in the HL, PM, and HLS. AP activity in HL appeared to vary with the sex of the grasshoppers. Females showed increase in AP activity in HL 18–24 h after injection with B. bassiana, whereas males only showed an increase 1 h after injection. Assay of HLS showed that the level of AP activity did not change significantly throughout the experiment. Changes in AP activity in PM, in both B. bassiana – and Tween‐80‐injected insects (both sexes) paralleled those of the HL, indicating that the enzyme is released from the HC. The observations are discussed in terms of the possible role of AP in the immune response of M. sanguinipes.

The relationship between the number of nuclei of an osteoclast and its resorptive capability in vitro.

This study examined the relationship between the number of nuclei in an osteoclast and its resorptive efficiency, as demonstrated by the size of the pit it can make in a mineralized tissue in 24 h in vitro. Osteoclasts released mechanically from prehatch chick long bones were cultured on dentine slices or on plastic dishes for periods of 6 or 24 h. The frequency distribution of the multinucleate tartrate-resistant acid phosphatase (TRAP)-positive cells with different numbers of nuclei was determined: the mean number of nuclei per cell was 6.92, with a mode of 4.47% had 5 or fewer nuclei and only 11% more than 10 nuclei. The pits associated with 292 osteoclasts with known numbers of nuclei were measured using a confocal laser light microscope (Lasertec) and dedicated image analysis system, and depths, plan areas and volumes determined. There was a positive correlation between the number of nuclei per osteoclast and the volume of the pit made, but a trend for the volume resorbed per nucleus to decrease with increase in the number of nuclei per osteoclast.

The Effect of haemolymph extraction on distribution of lysosomal enzymes in Lymnaea stagnalis haemocytes: A cytochemical study

An enzyme cytochemical, light microscopy study was undertaken to evaluate the effect of haemolymph extraction on distribution of acid phosphatase, alkaline phosphatase, alpha-naphthyl acetate esterase, and peroxidase in haemocytes of Lymnaea stagnalis. The study revealed that discrete acid phosphatase, alkaline phosphatase, alpha-naphthyl acetate esterase, and peroxidase-staining subpopulations of haemocytes do exist in L. stagnalis, and that there are differences in distribution. A high percentage, about 96%, of haemocytes showed positive reaction for peroxidase, the percentage of haemocytes showing activity for alpha-naphthyl acetate esterase, acid phosphatase, and alkaline phosphatase, was about 54, 42, and 34, respectively. Haemolymph extraction by foot retraction, significantly affected enzyme distribution. Whereas distribution of acid phosphatase increased significantly from day 1 to 5 after extraction of haemolymph, that of all other enzymes showed significant decrease from day 1 to 7 depending upon the enzyme. The distribution of all enzymes stabilized by day 8 after extraction of haemolymph. Probable reasons for the observed fluctuations in the distribution of enzymes subsequent to haemolymph extraction are discussed.

Structural and histochemical studies of Golgi complex differentiation in salivary gland cells during Drosophila development

Morphological alterations in the Golgi complex (GC) and changes in the distribution of acid phosphatase (AcPase), thiamine pyrophosphatase (TPPase), complex carbohydrates and reduced osmium tetroxide compounds in this organelle were studied in the salivary gland cells of Drosophila during larval and prepupal development. The morphology and the AcPase, TPPase and complex carbohydrates cytochemical patterns of the Golgi complex varied characteristically during cell differentiation. At the early 3rd instar period the Golgi complex consisted mainly of vesiculated cisternae, and AcPase activity was observed in all cisternae but not in the secretory granules. As development proceeded to the late 3rd instar the Golgi complex displayed its typical appearance, consisting of four to six cisternae, and only the two to three cisternae towards the trans-face as well as the trans-Golgi network and some of the immature secretory granules exhibited AcPase reactivity. In the course of a 'wave' of production of the 'glue' secretory granules proceeding proximally through the gland, the number of AcPase positive cisternae changed correspondingly. After secretion of the 'glue' secretory granules, the size of the Golgi complex decreased and almost all cisternae displayed AcPase reactivity. The detection of TPPase activity presented some specificity problems, since staining was observed not only in the GC cisternae but in the endoplasmic reticulum (ER) and microvilli. The reaction products were seen in a few GC vesicles during the early 3rd instar and in the trans side of the organelle at the end of the 3rd instar. During production of the secretory granules, every GC cisterna was intensely stained. These results agree with previous findings suggesting that AcPase and TPPase in secretory cells may be primarily involved in the processing of exportable proteins. The vicinal (vic)-glycol groups of the complex carbohydrates were detected using the periodic acid/thiocarbohydrazide/silver proteinate (PA-TCH-SP) technique. During synthesis of the 'glue' secretory granules, the reaction products were observed over the GC cisternae and the trans-Golgi network, with increasing intensity from the cis to the trans side of the organelle. No PA-TCH-SP staining was observed over the GC cisternae during the early 3rd instar. Following discharge of the 'glue' secretory granules, all GC cisternae displayed uniform PA-TCH-SP staining. After OsO4 impregnation, the reaction products were observed mainly in ER and mitochondria and rarely in the GC. In numerous cells, only the mitochondria were stained, while in many cases the ER of neighboring cells exhibited differential staining.(ABSTRACT TRUNCATED AT 400 WORDS)

Changes in the amount and distribution of neuronal alkaline and acid phosphatase after chronic exposure of cultures of cingulate cortex to antidepressant drugs.

Enzyme histochemistry was used to examine alkaline and acid phosphatases in cultures of embryonic rat cingulate cortex after 14 days exposure in vitro to two tricyclic antidepressants (amitriptyline and desipramine) and two non-tricyclic antidepressants (mianserin and citalopram). An increased amount of acid phosphatase reaction product was observed in lysosomes of neurons in cultures treated chronically with the non-tricyclic antidepressants, mianserin or citalopram. More strikingly, reaction product was also present in the inner lamellae of the Golgi apparatus after this treatment, but never in controls. These observations suggest that non-tricyclic antidepressants significantly increase the rate of degradative processes in cingulate neurons. In cultures, treated chronically with desipramine or amitriptyline, pre- and postsynaptic membranes contained heavy deposits of alkaline phosphatase reaction product, whereas in control cultures not exposed to these drugs the corresponding membranes were entirely devoid of reaction product. An increase in the amount of alkaline phosphatase reaction product was also observed on the plasma membranes of neuronal cell bodies. These observations suggest that chronic exposure to antidepressants may influence transmembrane transport in cingulate neurons.

Developmental alterations in nociceptive threshold, immunoreactive calcitonin gene‐related peptide and substance P, and fluoride‐resistant acid phosphatase in neonatally capsaicin‐treated rats

This study examined the effect of neonatal administration of capsaicin on nociceptive threshold and the distribution of calcitonin gene-related peptide (CGRP), substance P (SP), and fluoride-resistant acid phosphatase (FRAP) in the dorsal horn of the spinal cord during the course of development (10 days to 12 weeks of age) in the rat. As early as 10 days of age, CGRP-like immunoreactivity was reduced in laminae I, II, and V, as well as in the bundles of fibers situated dorsal and ventral to the central canal. However, beginning on or about 6 weeks of age, the density of CGRP-like immunoreactivity in the superficial laminae and in the bundles dorsal and ventral to the central canal increased. Moreover, thick, nonvaricose CGRP-like immunoreactive fibers appeared in laminae III and IV. These recurring fibers were of primary afferent origin as demonstrated by their disappearance after multiple, unilateral rhizotomies. A similar age-dependent alteration in the density of FRAP activity was also observed. Although virtually absent at 10 days of age after neonatal administration of capsaicin, the density of FRAP activity increased in lamina II by 8 weeks of age. This activity disappeared after multiple, unilateral rhizotomies, indicating that the FRAP activity that reappeared was of primary afferent origin. Neonatal administration of capsaicin also reduced the density of SP-like immunoreactivity in the dorsal horn as early as 10 days of age, although the density of SP-like immunoreactivity showed some recovery after 6 weeks of age. However, unlike CGRP-like immunoreactivity or FRAP activity, the density of SP-like immunoreactivity in capsaicin-treated rats was not detectably altered by multiple, unilateral rhizotomies, indicating that it originated principally from intrinsic dorsal horn neurons. Age-dependent alterations in both thermal and mechanical, but not chemical, nociceptive thresholds were also observed in these same animals. Thus, tail flick latency, hot plate latency, and paw withdrawal threshold were maximally increased at 6 weeks of age, after which time thresholds declined to vehicle-treated values. In contrast, capsaicin-treated animals were uniformly insensitive to ophthalmic administration of capsaicin. The correspondence between developmental alterations in CGRP-like immunoreactivity or FRAP activity and in thermal and mechanical nociceptive thresholds is suggestive of a role of CGRP- or FRAP-containing primary afferents in thermal and mechanical nociception.

Ossification in nude mice. 2.

The autopodia of proximal limbs as well as the proximal growth plates of the tibia of newborn nu/ nu including super nu/nu, nu/+ and +/+mice were studied. No differences in the ossification of proximal limb autopodia (regarding the distribution of alkaline phosphatase, acid phosphatase or glycosaminoglycans) were observed in mice of genotypes studied. On the other hand, a thinner proximal tibial growth plate characterizes one‐month‐old nu/nu mice, and also the architecture and alkaline phosphatase pattern were altered. The results suggest a postnatal secondary effect of the nu/ nu genotype on skeletal development.

Acid phosphatase activity during spore differentiation of the red algaeGigartina teedii andChondria tenuissima

The acid phosphatase activity during carposporogenesis inGigartina and tetrasporogenesis inChondria was studied using the Gomori technique. During the first steps of gonimoblast maturation ofGigartina, portions of cytoplasm are ensheathed by ER cisternae with acid phosphatase activity, giving rise to autolysosomal concentric membrane bodies. In a similar way large mucilage sacs are severed. They extrude their contents in a kind of exocytosis. Multivesicular bodies, concentrically arranged cisternae and extracytoplasmic compartments, each with acid phosphatase activity, remain in young carpospores for some time, probably as remnants of the autophagocytotic and exocytotic events. The Golgi apparatus is poorly developed in gonimoblast cells and young carpospores. It becomes a prominent cell component in maturing carpospores and then participates in cell wall formation. Only some of the dictyosomal cisternae contain acid phosphatase; these are irregularly distributed in the dictyosome. — In pre- and postmeiotic tetraspore mother cells ofChondria massive lead deposits are found in the dictyosomes and in adjacent Golgi vesicles. Finer lead precipitates occur in ER cisternae, especially in those which are sequestering starch-grain-containing portions of the cytoplasm to give rise to autolysosomes. During cell cleavage, the dictyosomes aggregate. They become devoid of acid phosphatase activity with the exception of vesicles at the trans face. Later, Golgi stacks associate and have common, Gomori positively reacting, narrow cisternae at the cis face. The Golgi apparatus derived “cored vesicles” do not contain lead precipitates whereas the Golgi cisternae in the final stage of tetrasporogenesis show acid phosphatase activity. Variations in acid phosphatase distribution are explained in the light of current models of membrane flow.

Lysosomal depletion in macrophages from spleen and foot lesions of Leishmania-infected hamster

Analysis of lysosomes through acid phosphatase cytochemistry at the electron microscopy level has been performed in spleen and foot lesions from Leishmania-infected hamsters. The results showed that there is lysosomal depletion in macrophages from Leishmania donovani chagasi-infected hamster spleen and similar findings were obtained from foot lesions of Leishmania mexicana amazonensis-infected hamsters. The distribution of acid phosphatase and thiamine pyrophosphatase was also examined in the Golgi apparatus. It was possible to demonstrate that the activity of ACP is absent in infected macrophages from spleen and foot lesions of Leishmania-infected hamster while the distribution of TPP was very similar in control and infected macrophages from both systems. These results provide evidence that the lysosomal depletion can occur at the ACP synthesis and/or glycosylation level.

Histochemistry and biochemistry of tartrate-resistant acid phosphatase (TRAP) and tartrate-resistant acid adenosine triphosphatase (TrATPase) in bone, bone marrow and spleen: implications for osteoclast ontogeny

In order to evaluate the usefulness of a recently described acid ATPase as a marker for osteoclast differentiation, we have performed histochemical and biochemical analyses of the distribution of tartrate-resistant acid phosphatase (TRAP) and tartrate-resistant acid ATPase (TrATPase) in bone, bone marrow and spleen. Histochemical studies of bone demonstrated that multinucleated osteoclasts stained for both TRAP and TrATPase. However, staining for TRAP covered the entire cytoplasm, whereas TrATPase staining was localized primarily to cytoplasmic areas next to bone and on adjacent mineralized surfaces. Occasionally TrATPase-positive mononuclear cells were observed on excavations in the bone surface. In the spleen, mononuclear TRAP-positive cells were located in the marginal zone between the white and red pulp, whereas no staining for TrATPase was observed. Comparison of the biochemically measured TRAP and TrATPase activities showed that bone had the highest specific activity for both enzymes followed by the bone marrow and spleen. However, enzyme activity in the spleen compared to bone was about 4-fold higher for TRAP compared to TrATPase. Additional evidence for a restricted expression of TrATPase to bone relative to spleen was obtained by in vitro translation studies. These data indicate that TrATPase is a more selective marker than TRAP in histochemical and biochemical studies of osteoclast differentiation and furthermore suggest that development of TrATPase is a late acquisition in osteoclast ontogeny.

In exocrine pancreas, the basolateral endocytic pathway converges with the autophagic pathway immediately after the early endosome.

Intracisternal granules (ICGs) are insoluble aggregates of pancreatic digestive enzymes and proenzymes that develop within the lumen of the rough endoplasmic reticulum of exocrine pancreatic cells, especially in guinea pigs. These ICGs are eliminated by autophagy. By morphological criteria, we identified three distinct and sequential classes of autophagic compartments, which we refer to as phagophores, Type I autophagic vacuoles, and Type II autophagic vacuoles. Lobules of guinea pig pancreas were incubated in media containing HRP for periods of 5-120 min to determine the relationship between the endocytic and autophagic pathways. Incubations with HRP of 15 min or less labeled early endosomes at the cell periphery that were not involved in autophagy of ICGs, but after these short incubations none of the autophagic compartments were HRP positive. After 30-min incubation with HRP, early endosomes at the cell periphery, late endosomes in the pericentriolar region, and, in addition, Type I autophagic vacuoles containing ICGs were all labeled by the tracer. Type II autophagic vacuoles were not labeled after 30-min incubation with HRP but were labeled after incubations of 60-120 min. Phagophores did not receive HRP even after 120 min incubations. We concluded that the autophagic and endocytic pathways converge immediately after the early endosome level and that Type I autophagic vacuoles precede Type II autophagic vacuoles on the endocytic pathway. We studied the distribution of acid phosphatase, lysosomal proteases and cation-independent-mannose-6-phosphate receptor (CI-M6PR) in the three classes of autophagic compartments by histochemical and immunocytochemical methods. Phagophores, the earliest autophagic compartment, contained none of these markers. Type I autophagic vacuoles contained acid phosphatase but, at most, only very low levels of cathepsin D and CI-M6PR. Type II autophagic vacuoles, by contrast, are enriched for acid phosphatase, cathepsin D, and other lysosomal enzymes, and they are also enriched for CI-M6PR. Moreover, soluble fragments of bovine CI-M6PR conjugated to colloidal gold particles heavily labeled Type II but not Type I autophagic vacuoles, and this labeling was specifically blocked by mannose-6-phosphate. This indicates that the lysosomal enzymes present in Type II autophagic vacuoles carry mannose-6-phosphate monoester residues. Using 3-C2, 4-dinitroanilino-3'-amino-N-methyldipropylamine (DAMP), we showed that Type II autophagic vacuoles are acidic. We interpret these findings as indicating that Type II autophagic vacuoles are a prelysosomal compartment in which the already combined endocytic and autophagic pathways meet the delivery pathway of lysosomal enzymes.

Ultrastructural Localization of ATPases in the Gastrodermis of Megalodiscus temperatus with Additional Observations on Schistosoma japonicum (Trematoda: Digenea)

Ultrastructural Localization of ATPases in the Gastrodermis of Megalodiscus temperatus with Additional Observations on Schistosoma japonicum (Trematoda: Digenea)

Distribution pattern of acid phosphatase activity in human peripheral blood leukocytes: a cytochemical scanning electron microscopy study

The distribution patterns of acid phosphatase hydrolytic activity were studied in human peripheral blood cells with enzymocytochemical techniques together with light and scanning electron microscopy in the secondary and backscattered electron imaging modes. The acid phosphatase reaction product was seen in three different patterns of distribution: focal, granular and diffuse. These patterns were correlated with similar findings obtained with light microscopy. Acid phosphatase distribution patterns seen with SEM in the BEI mode were also correlated with the surface morphology of peripheral blood cells seen in the SEI mode. Cells exhibiting the focal pattern were smooth-surfaced with few microvilli; cells showing a granular pattern presented microvilli and microridges; ruffles were characteristic of cells with a diffuse pattern of activity. No reaction product was seen in cells bearing microvilli or ridges. Our findings demonstrate the correlation between acid phosphatase activity patterns and surface features in different subpopulations of peripheral blood cells.