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A Cadoni

Publications and source records attributed to A Cadoni.

At least 37 records · Page 2Linked to original sources
PubMed1984

Granule formation in large granular lymphocytes (LGL). Ultrastructural and cytochemical studies on cells from patients with abnormally expanded lgl populations.

The peripheral blood mononuclear cells from five patients with abnormally expanded populations of large granular lymphocytes (LGL) of possible malignant origin have been studied by electron microscopy. These cells had fewer granules than normal circulating LGL but displayed a variety of organelles possibly involved in the process of granule formation. This process apparently originated from the fusion of vesicles that had a characteristic cup-shape (and appeared to be derived from the Golgi apparatus) with smaller vesicles, mostly of the coated type. This fusion resulted in the formation of multivesicular bodies (MVB) whose limiting membrane was constituted by that of the cup-shaped vesicle. MVB gradually matured into electron-dense granules. A number of cup-shaped vesicles were found positive for the cytochemical localization of thiamine pyrophosphatase (TPP) activity that is a specific marker of the trans aspect of the Golgi apparatus, a finding which confirmed that they were Golgi-derived. The smaller, mostly coated, vesicles were positive for acid phosphatase (AP) and evidence was obtained indicating that they subserved the function of transporting acid hydrolases from the rough endoplasmic reticulum to the cup-shaped vesicles or to the MVB. The plasma membrane did not appear to contribute to MVB or granule formation since endocytic vacuoles induced by reacting the cell surface with the appropriate monoclonal antibodies (followed by peroxidase labelled anti-immunoglobulin) were never seen while fusing with granules or MVB. Rather, these vesicles formed secondary lysosomes after having encountered smooth or, more rarely, coated vesicles. Granulogenesis in LGL, therefore, resembles the process of granule formation observed in secretory cells. The active process of granulogenesis detected in the patient cells and a number of other findings indicate that they were LGL at early stages of maturation. The surface phenotype consistently found in these cells (OKT3+, Leu 1+, OKT8+, Leu 2a+, OKT11+, Leu 5+ and OKM1) is different from that of the majority of the normal LGL and may correspond to that of immature LGL.

Acid Phosphatase↗
PubMed1983

Analysis of human peripheral blood lymphocytes isolated by counterflow centrifugation-elutriation.

Human peripheral blood mononuclear cells isolated by Ficoll-Hypaque density gradient centrifugation have been fractionated by counterflow centrifugal elutriation (CCE). Six CCE fractions were obtained and subsequently analyzed as for their content of monocytes, T cells, NK cells and B cells. The various cell types were identified through the expression of specific surface membrane determinants or by cytochemical staining for alpha-naphthyl acid esterase (ANAE). Monocytes were elutriated at the highest counterflow rates whereas the majority of B cells were collected at the lowest counterflow rates. T cells as well as NK cells were mostly concentrated in the intermediate fractions. No differences in the elutriation profile of T cells with the helper-inducer or with the cytotoxic-suppressor surface phenotype were observed. However, the percentages of T cells as determined by surface marker expression decreased with increasing counterflow rates, whereas the percentage of ANAE-positive T cells increased. Yet, T cells recovered at the high counterflow rates had ANAE-reactive organelles larger than those of T cells collected at low counterflow rates. These findings suggest that T cells at different maturational stages could be separated by CCE.

B-Lymphocytes↗
PubMed1983

Ultrastructural characteristics of human T cell clones with various cytolytic activities.

Fifteen T cell clones with different (specific, antibody-dependent or natural killer-like) cytolytic activity were derived from mixed lymphocyte culture activated T cells and analyzed for their morphological characteristics and, in some instances, for their surface markers. All of the five cytolytic clones analyzed by electron microscopy possessed numerous electron-dense granules and in some instances multivesicular bodies, with or without an electron-dense matrix, that are the putative precursors of the granules. In addition, light microscopy examination of semithin sections of other ten cytolytic clones showed that the large majority of the cells in each clone had numerous toluidine blue-stained cytoplasmic granules. It is of note that nine clones without detectable cytolytic activity analyzed by electron microscopy did not possess granules and presented the features of large agranular blasts. Ten cytolytic clones were analyzed for different surface markers including rosette formation with sheep erythrocytes (E rosettes), receptors for the Fc portion of IgG or IgM ((Fc gamma R and Fc mu R) and a group of antigens recognized by monoclonal antibodies including Ia, 4F2, OKT8 or OKT4. All the clones were E-rosette+, Ia+ and 4F2+. Expression of Fc gamma R was restricted to the clones active in antibody-dependent cell-mediated cytotoxicity. Expression of OKT8 and OKT4 antigens was variable; in particular, five clones were OKT8+/OKT4-, whereas the other five expressed the OKT8-/OKT4+ phenotype. It is noteworthy that the ultrastructural features of cytolytic T cell clones are similar to those of large granular lymphocytes, known to be the only lymphoid cells in normal peripheral blood which possess cytolytic activity. Thus, it is possible that the presence of electron-dense granules may represent a morphological marker for all human cytolytic lymphocytes.

Antigens, Surface↗
PubMed1982

Phenotypic and functional characterization of a Sézary cell.

We have studied the surface antigen pattern, enzymatic phenotype, and functional capacity of peripheral blood lymphocytes from a patient with Sézary syndrome (SS). The majority of these cells formed E rosettes but lacked the Fc(mu) receptor. The neoplastic cells were reactive with pan-T cell (OKT3)- and helper T cell (OKT4)-subset monoclonal antibodies; however, they lacked the 5/9 antigen, which identifies a more restricted subset of helper T cells. Most SS cells also reacted with PTF 29.12, a monoclonal antibody which recognizes DR determinants. Only 35% of the cells expressed single, focal accumulations of alpha-naphthyl-acid esterase activity, which is a characteristic of T.M cells, but 85% of them showed this focal staining pattern with acid phosphatase or beta-glucuronidase. Mononuclear cells from the SS patient showed poor or no proliferative response to phytohemagglutinin, pokeweed mitogen, concanavalin A, purified protein derivative, Candida, and allogeneic cells and lacked both helper and suppressor activity for pokeweed mitogen driven production of IgM and IgG immunoglobulins by normal B cells, but they were able to stimulate a marked proliferative response in mixed-lymphocyte culture. The defective expression of enzymatic and surface membrane characteristics, together with the lack of some T-cell functions, suggests that the patient cells may be immature T.M lymphocytes.

Aged↗
PubMed1982

Immunofluorescent and ultrastructural analysis of plasma cell degeneration in the chicken Harder's gland.

In this study we describe some aspects of plasma cell degeneration in the chicken Harder's gland. The immunofluorescent patterns of cytoplasmic immunoglobulin (cIg) localization have been studied in relation to the ultrastructure of maturing and degenerating B cells. It appears that Russell body formation through the accumulation of Ig within the cisternae of the rough endoplasmic (RER) does not represent the only mechanism for the formation of cytoplasmic vacuoles. Mitochondrial swelling and disruption or dilation of Golgi cisternae, often preceding alterations of the RER, may be the origin of some vacuoles. It also appears that, in the Harder's gland, degeneration may occur not only in mature plasma cells but also in maturing B cells at a stage when only clusters of polyribosomes are found in the cytoplasm and no RER is yet developed. These observations are relevant to some immunofluorescence and ultrastructural patterns observed in human B-cell pathology.

Animals↗
PubMed1982

Receptors for the third complement component on a proportion of large granular lymphocytes from human peripheral blood.

Large granular lymphocytes (LGL) are nonadherent cells with cytoplasmic azurophilic granules, avid receptors for the Fc portion of IgG, and a paranuclear localization of alpha-naphthyl acid esterase or acid phosphatase. LGL constitute the bulk of TG cells (cells with receptors for sheep erythrocytes and for IgG molecules) and null cells (non-T, non-B cells). In the present study we demonstrate that 20-33% of the circulating human LGL express receptors for the third complement component (C3R). When TG cell or null cell fractions from normal individuals or non-T cells from a patient with infantile agammaglobulinaemia (which contained almost exclusively LGL) were rosetted with erythrocytes coated with antibody and complement, a variable number of C3R-bearing cells were detected. Such cells were isolated and analysed further; the great majority of them displayed the cytochemical and ultrastructural features of LGL.

Acid Phosphatase↗
PubMed1982

Acid hydrolases as markers of maturation in B-cell chronic lymphocytic leukemia.

Malignant lymphocytes from 30 B-cell chronic lymphocytic leukemia (B-CLL) patients were studied for the cytochemical localization of two acid hydrolases, alpha-naphthyl acetate esterase (ANAE) and acid phosphatase (AT). The large majority of the cells stained for both ANAE and AP in 7 cases, for AP only in 18 cases, and were negative for both the enzymes in 5 cases. Ultrastructural analysis revealed that the cells that displayed more mature morphological features, such as well developed smooth and rough membrane compartments, were those positive for acid hydrolases. That ANAE and AP are expressed by B cells at late stage of maturation was confirmed by the finding that some lymphocytes and all of the plasmacytoid lymphocytes and plasma cells from Walderström's macroglobulinemia, from mixed cryoglobulinemia, and from multiple myeloma patients stained strongly for both ANAE and AP. Using the expression of acid hydrolases and certain ultrastructural features as markers of cell differentiation, it was possible to demonstrate a process of maturation within the single B-CLL clones with accumulation of the cells at stages that differed in the various cases.

Acid Phosphatase↗
PubMed1982

Large granular lymphocytes in human peripheral blood: ultrastructural and cytochemical characterization of the granules.

Large granular lymphocytes (LGL) are defined as nonadherent mononuclear cells with cytoplasmic azurophilic granules, avid receptors for the Fc portion of IgG, and cytotoxic functions (NK or ADCC activities). In the present study, the granules of LGL isolated from human peripheral blood have been analyzed by enzyme cytochemistry and electron microscopy. It had been found that: (1) in the single cells, granules at different stages of maturation could be detected: in addition, packaging of the granules took place in the proximity of the Golgi apparatus, which is similar to that seen in secretory cell types. (2) Acid phosphatase (AP) was observed within the granules and the vesicles located in the Golgi area: the Golgi apparatus identified through its thiamine pyrophosphatase-positivity was consistently negative for AP. (3) Alpha naphthyl-acetate esterase (ANAE) activity was localized in the granules as well as on the membrane of LGL and monocytes. (4) The ANAE activity of LGL was of the monocytic and not of the lymphocytic type, as shown by NaF inhibition. (5) The LGL granules, although identifiable as primary lysosomes, were not involved in the process of phagocytosis, since LGL failed consistently to ingest latex particles or opsonized red cells.

Acid Phosphatase↗
PubMed1981

Ultrastructural localization of alpha-naphthyl acid esterase in human TM lymphocytes.

The localization of alpha-naphthyl acid esterase (ANAE) activity in T lymphocytes with receptors for IgM (T(M) cells) have been studied at the electron microscope. The electron-opaque product of the cytochemical reaction was detected around, but never inside, single (or groups of) vesicles, which suggested a possible membrane localization of the enzyme activity. These same vesicles were found to contain acid phosphatase by both light- and electron-microscopic examination and were bound by unit membranes; this data indicates that they likely represent primary lysosomes. The presence of such lysosomes in a restricted paranuclear area is a distinctive feature of T(M) cells.

Acid Phosphatase↗
PubMed1980

Ultrastructure and cytochemistry of human peripheral blood lymphocytes. Similarities between the cells of the third population and TG lymphocytes.

The ultrastructural and cytochemical features of human peripheral blood TG cells (T cells with receptors IgG) and of the cells of the so-called third population (non-T, non-B cells with high avidity receptors for IgG) have been investigated and compared. Both TG and third-population cells (TPC) contained acid hydrolases with a paranuclear localization of alpha-naphthyl acid esterase, beta-glucuronidase or acid phosphatase. At the electron microscopy level, TG and TPC were indistinguishable and displayed rough cell surface, indented nuclei, abundant cytoplasm with predominance of the smooth over the rough membranes and peroxidase-negative granules. A large proportion of cells of the TPC could form rosettes with sheep erythrocytes after treatment with neuraminidase. The observed close similarities between TG and TPC may suggest that both cell types belong to a special subset of T cells. However, the alternative hypothesis that both TG and TPC are part of a subset unrelated to T cells, such as a new non-T, non-B cell population, or even of the monocytic-macrophage lineage, is also discussed.

Histocytochemistry↗
PubMed1978

Surface markers on lymphocytes from human cerebrospinal fluid. Predominance of T lymphocytes bearing receptors for the Fc segment of IgG.

Surface markers of cerebrospinal fluid (CSF) cells have been studied in comparison with those of peripheral blood lymphocytes. The great majority (about 95%) of CSF cells bear surface markers of thymus-dependent lymphocytes (E rosettes with uncoated sheep red blood cells), while being devoid of bone-marrow derived cell markers (EAC rosettes with complement-coated red blood cells). In contrast with lymphocytes from peripheral blood, CSF cells form predominantly 'early' and 'sphere'-shaped E rosettes, and bear receptors for the complement-fixing segment of immunoglobulins G. Treatment with concentrated CSF does not affect rosette forming ability of peripheral blood lymphocytes.

Cerebrospinal Fluid↗
PubMed1978

Subpopulations of T lymphocytes in human extravascular fluids.

Surface markers of lymphocytes from various human extravascular fluids (cerebrospinal fluid, aqueous humour, colostrum, breast and ovary cyst fluids, peritoneal and pleural transudates) are compared with those of lymphocytes from peripheral blood. Significantly higher percentages of T cells are found in all extravascular fluids: the great majority of extravascular T lymphocytes show high E rosette-forming ability and bear IgG Fc receptors (T Fc+ cells). Functional implications of the shown high predominance of T Fc+ cells in extravascular fluids are discussed on the basis of presently available information on the immunological role of such cells (cytotoxic? suppressor? amplifier?).

Antigens↗