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Biomedical subjects

V Desmet

Publications and source records attributed to V Desmet.

At least 91 records · Page 5Linked to original sources
PubMed1987

Expression of leukocyte common antigen in lymphoblastic lymphoma and small noncleaved undifferentiated non-Burkitt's lymphoma: an immunohistochemical study.

Nine cases of lymphoblastic lymphoma and eight cases of small, noncleaved undifferentiated non-Burkitt's lymphoma were studied. All cases were stained with monoclonal antibodies, directed to the leukocyte common antigen (LCA), B- and T-cell markers as well as Calla. Small noncleaved, undifferentiated non-Burkitt's lymphomas were LCA positive and expressed one or more B-cell markers. Three cases of lymphoblastic lymphoma were LCA positive and showed reactivity with antibodies OKT4, OKT6 and OKT8. The six remaining cases of lymphoblastic lymphoma were LCA negative, except for only one case that was weakly LCA positive using more sensitive detection methods. Two of the LCA negative cases expressed Calla, and four cases did not show any reactivity with the monoclonal antibodies used. In all LCA negative cases, small residual non-neoplastic nodules representing remnants of lymphoid follicles, could be detected. Since five out of nine cases of lymphoblastic lymphoma were LCA negative, lack of staining for LCA does not preclude the diagnosis of lymphoma.

Adolescent↗
PubMed1987

Immunocytological study of phlyctenular eye disease.

Scrapings from phlyctens and conjunctiva of 12 patients with phlyctenular keratoconjunctivitis were studied using OKT4-Leu3a, OKT8, B1, BA1, S-100 and HLA-DR monoclonal antibodies. T-lymphocytes were present in both conjunctival and phlyctenular scrapings. OKT4-Leu3a positive cells outnumbered the OKT8 positive cells in both conjunctival and phlyctenular scrapings. B1 and BA1 positive cells were absent from the conjunctival scrapings, but were present in the phlyctenular scrapings. S-100 positive cells were present in both conjunctival and phlyctenular scrapings. However, they were very few in the conjunctival scrapings. Most of the cells in both conjunctival and phlyctenular scrapings were HLA-DR positive. These findings support the hypothesis that cell mediated immunity is responsible for the pathogenesis of phlyctenular eye disease.

Adolescent↗
PubMed1987

Immunohistochemical study of epidermal Langerhans cells and dermal dendritic cells in benign and malignant skin lesions characterized by a dermal lymphoid infiltrate consisting either of B-cells or T-cells.

Skin biopsies from 43 patients with a rather dense dermal lymphoid infiltrate of either inflammatory or neoplastic nature have been investigated. We studied the number, distribution and immunophenotype of epidermal Langerhans cells and dermal dendritic cells. As previously reported, differences in epidermal Langerhans cell and dermal dendritic cell numbers between skin biopsies with a B-cell infiltrate and skin biopsies with a T-cell infiltrate were found, dendritic cells being more numerous in the latter. The main finding of this study was an uneven distribution of epidermal Langerhans cells and dermal dendritic cells in skin biopsies with a T-cell infiltrate: in skin lesions with an inflammatory lymphoid infiltrate, small clusters of epidermal and dermal dendritic cells admixed with T-lymphocytes (predominantly T-helper/inducer cells) and small blood vessels were present at areas of exocytosis. In skin lesions with a neoplastic lymphoid infiltrate larger, more loosely arranged aggregates of dendritic cells and T-cells were seen. These cell aggregations composed of activated (inflammatory or neoplastic) T-cells and dendritic cells may represent the cutaneous homologue of the secondary T-nodule in the lymph node. Both types of cell aggregates may correspond to the dendritic cell-T cell clusters observed in in vitro induced immune responses.

B-Lymphocytes↗
PubMed1987

Jejunal mucosa lymphoid cell subsets and the expression of major histocompatibility complex antigens in children.

Using monoclonal antibodies with the immunoperoxidase technique the distribution pattern of class I and class II antigens of the major histocompatibility complex (MHC), and of the lymphocyte subsets have been studied in intestinal biopsies from children without mucosal lesions, from children with coeliac disease (CD) and from infants with cow's milk protein intolerance (CMPI). The staining of the intestinal mucosa for class I antigens is unaltered irrespective of the histological picture or the clinical diagnosis. Class II antigens are only partially or not expressed at all by epithelial cells in untreated coeliac disease and in some cases of cow's milk protein intolerance. The number and the composition of the lamina propria lymphocytes in both CD and CMPI are different from the normal situation. An increase of all lamina propria lymphocyte subsets is observed in untreated CD. A decrease of OKT4+ lymphocytes is observed in the lamina propria of CMPI patients. These changes may be involved in the pathogenesis of these diseases.

Animals↗
PubMed1987

Ulcerative colitis, primary sclerosing cholangitis, bile duct carcinoma, and generalized sarcoidosis. Report of a unique association.

We describe a young man with a hitherto unreported association of chronic ulcerative colitis, primary sclerosing cholangitis (PSC), bile duct carcinoma, and generalized sarcoidosis with features of high-intensity alveolitis. This finding suggests that common immunological mechanisms may be involved in the pathogenesis of these diseases.

Adenocarcinoma, Scirrhous↗
PubMed1987

Epidermal Langerhans' cells and dermal dendritic cells in human fetal and neonatal skin: an immunohistochemical study.

The dendritic cells in skin biopsies from 36 fetuses (from 16 weeks' gestational age on) and neonatal infants of different ages were investigated using a number of markers for various cells of the immune system and immunohistochemistry. Epidermal Langerhans' cells were found in all cases in a predominantly basal localization. The number of OKT6-positive Langerhans' cells and the development of their dendritic processes gradually increased with age. Dermal dendritic cells were present as well. Both HLA-DR-positive and Leu-10-positive dermal dendritic cells were found in the superficial and deep dermis, often in a perivascular distribution. The OKT6-positive dermal dendritic cells were few in number and occurred only in the upper dermis.

Abdomen↗
PubMed1987

Cytological and immunohistochemical study of the limbal form of vernal keratoconjunctivitis by the replica technique.

The cellular composition of the inflammatory infiltrate present in 13 patients with the limbal form of vernal keratoconjunctivitis was examined in the conjunctival scrapings and the limbic replicas by means of Giemsa stain and immunohistochemistry. Conjunctival scrapings showed the presence of mast cells, lymphocytes, plasma cells, polymorphonuclear leucocytes, and very few basophils in all the specimens. Eosinophils were present in only four scrapings. The superficial epithelium of the limbic lesion and the adjacent cornea and conjunctiva was studied by the replica technique. The limbic lesion area showed the presence of necrotic epithelial cells mixed with inflammatory cells, including eosinophils, mast cells, lymphocytes, plasma cells, and polymorphonuclear leucocytes and very few basophils. Most of the inflammatory cells were HLA-DR+. Many OKT6+ cells were present, indicating the presence of Langerhans cells. T-lymphocytes including a few helper/inducer cells and many suppressor/cytotoxic cells, were detected in the infiltrate. In addition many B-lymphocytes were observed. These findings suggest that other immune mechanisms in addition to type 1 reaction are involved in the pathogenesis of the disease.

Adolescent↗
PubMed1986

The cellular composition of granulomas in mesenteric lymph nodes from patients with Crohn's disease.

The immunohistochemical findings in granulomatous lymphadenitis in patients with Crohn's disease are presented and compared with conventional light microscopic findings. The cellular composition of the granulomas in mesenteric lymph nodes was examined with a broad panel of monoclonal and polyclonal antibodies directed to B-cells, T-cells, monocytes/macrophages, dendritic reticulum cells, HLA-DR antigens and the transferrin receptor. The centre of the granulomas contains OKIa+, OKM1+, OKT9+, DRC-, To5- epithelioid cells and giant cells and OKT3+ lymphocytes. In general, the majority of the small lymphocytes within the granulomas expresses the OKT3+, OKT4+ Leu 3a+ phenotype which points toward T-helper cells. Fewer OKT3+ OKT8+ T suppressor/cytotoxic cells are observed. At the periphery of the granulomas a lymphocytic corona composed of BA1+, B1+ B lymphocytes may be present. From these findings it can be concluded that the granulomas in mesenteric lymph nodes from patients with Crohn's disease are composed of centrally located T-lymphocytes and of epithelioid cells which are of monocyte/macrophage origin and have the characteristics of antigen-presenting cells.

Adolescent↗
PubMed1986

Merkel cell tumor of the skin: an immunohistochemical study.

Skin biopsy specimens from 12 elderly patients with Merkel cell tumors were investigated. Conventional light microscopy and immunohistochemical techniques were used. All of the tumors had similar morphologic features. Immunoreactivity for neuronspecific enolase, gastrin, calcitonin, and epithelial membrane-like antigen was demonstrated, and both neurofilaments and keratin filaments were observed. The immunohistochemical findings supported a Merkel cell origin for these Merkel cell tumors. The co-expression of neuroendocrine and epithelial markers in Merkel cell carcinomas is suggestive of neuroendocrine differentiation in a neoplasm of epithelial origin. Merkel cell carcinomas share many characteristics with neuroendocrine tumors of the bronchopulmonary and gastrointestinal tracts. All of these neoplasms may originate from cells of similar types that are present in several organs.

Aged↗
PubMed1986

'Lupus' anticoagulant and thrombosis of the hepatic veins (Budd-Chiari syndrome). Report of three patients and review of the literature.

Three patients with Budd-Chiari syndrome in association with the 'lupus' anticoagulant are described. This anticoagulant was looked for in our patients with an otherwise idiopathic hepatic venous thrombosis because of the presence of a pronounced thrombocytopenia, a prolonged activated partial thromboplastin time or a history of repeated abortions and deep leg vein thrombosis, respectively. An active search for the 'lupus' anticoagulant should be performed to lower the percentage of apparently idiopathic cases of Budd-Chiari syndrome.

Adult↗
PubMed1986

The histological characterization of ALIP in the myelodysplastic syndromes.

Bone marrow biopsies of patients with a myelodysplastic syndrome (MDS) may, in the absence of an increased number of blasts in the bone marrow smears, contain small clusters of immature precursors. The presence of these cell nests, previously described as "abnormal localized immature precursors" or ALIP, bears a strong prognostic value predisposing patients to early death with an increased risk to develop myeloid leukaemia. In order to describe and delineate this histological characteristic more precisely, we compared bone biopsies of patients with MDS, used in these previous studies, with bone marrow biopsies performed for staging procedures in patients with Hodgkin's disease, non-Hodgkin's lymphoma and carcinoma. From this comparison we conclude that immature precursors are readily differentiated from proerythroblasts, myeloblasts and small-sized megakaryocytes, and that they most probably represent precursors of the myelo-monocytic-erythroid series. A clearcut increase in their number, mostly resulting in the formation of small clusters, is only found in biopsies from patients with MDS.

Bone Marrow↗
PubMed1986

Immunoelectron microscopic investigation of HLA-DR-positive dendritic cells at the dermo-epidermal junction in skin disorders associated with the deposition of immune complexes.

HLA-DR-positive dendritic cells present at the dermo-epidermal junction in skin disorders associated with the deposition of immunoglobulins and/or complement factors in the skin biopsy are investigated ultrastructurally. They demonstrate long, slender cytoplasmic processes, an indented nucleus, and strikingly dilated cisternae of the endoplasmic reticulum. HLA-DR antigen is present on the plasma membrane and within some of the dilated cisternae. These findings further support our previously formulated hypothesis that these cells represent a functionally active stage of antigen-presenting cells.

Antigen-Antibody Complex↗
PubMed1986

Expression of HLA-DR and T6 antigens on keratinocytes and dendritic cells. A comparative immunohistochemical study.

The number, morphology, and distribution of cells with dendritic processes in the epidermis and dermis, as well as the expression of HLA-DR and T6 antigen on keratinocytes in 66 skin biopsy specimens have been studied. In the epidermis, OKT6+ cells with slender dendritic processes predominated in the upper layers and outnumbered OKIa1+ cells with dendritic processes, which were only fragmentarily stained and present throughout all layers. In the dermis, OKIa1+ cells with dendritic processes outnumbered OKT6+ cells with dendritic processes. Cases showing keratinocytic positivity for OKIa1 contained very few epidermal OKIa1+ cells with dendritic processes; cases showing surface staining of keratinocytes with OKT6 contained high numbers of epidermal OKT6+ cells with dendritic processes. We suggest that OKT6 and OKIa1 label distinctive subpopulations of epidermal and dermal dendritic cells and, as such provide complementary data.

Antibodies, Monoclonal↗
PubMed1985

Ia+ dendritic cells lining the dermo-epidermal junction in bullous skin disorders, associated with the deposition of immune complexes.

Skin biopsies from 34 patients, presenting with a variety of bullous skin disorders were investigated, using routine light microscopy and immunohistochemistry. In bullous skin diseases characterized by deposition of complement factors (CF) and/or immunoglobulins (Ig), a monolayer of OKIa+1, OKT-6, OKM-1 dendritic cells was found at the dermo-epidermal junction. Retrospectively, these cells were easily recognized on paraffin embedded, H & E stained material. In bullous skin disorders, showing no deposition of CF and/or Ig, this monolayer of dendritic cells was lacking. It is suggested that these OKIa+1, OKT-6, OKM-1 dendritic cells at the dermo-epidermal junction represent some type of antigen presenting cells, not corresponding to Langerhans cells, veiled cells or indeterminate cells.

Antibodies, Monoclonal↗
PubMed1985

Gastric leiomyoblastoma with metastases to the liver. A 36-year follow-up study.

A patient presented with large intrahepatic tumoral masses 36 yr after the initial detection of multiple liver metastases during a gastrectomy. The operation had been performed to remove four ulcerated polypoid gastric lesions. Reexamination of the previous liver and gastric biopsy specimens revealed a gastric leiomyoblastoma with metastases to the liver. The smooth muscle origin of this tumor was confirmed by positive staining for desmin intermediate filaments. This very long survival is extremely unusual in cases of metastatic gastric leiomyoblastoma.

Adolescent↗
PubMed1985

Cimetidine-induced liver injury. Report of three cases.

Cimetidine-induced liver injury has only very rarely been reported. Three patients are described who developed signs of hepatic damage after the institution of cimetidine therapy. Transient signs of acute liver failure were noticed in one patient. Histologically, a cytotoxic type of injury with centrilobular confluent and bridging portal-central necrosis, accompanied by a mixed mono- and polymorphonuclear infiltrate with signs of cholangiolitis in the portal tracts was observed in two patients, whereas a hepatocanalicular type of cholestatic hepatitis was noticed in another patient. It is proposed that the mechanism of cimetidine-induced liver injury may vary in different patients: it may be due either to a 'metabolic idiosyncrasy' because of the production of hitherto unknown toxic metabolites or to a hypersensitivity reaction.

Aged↗
PubMed1985

Expression of MHC Class II antigens by oesophageal epithelium in herpes simplex oesophagitis.

An immunoperoxidase technique with monoclonal antibodies for the identification of lymphocyte subsets and MHC Class II antigens was applied to oesophageal biopsies from two patients with herpetic oesophagitis. Oesophageal epithelial cells were found to express the MHC Class II antigen. The inflammatory infiltrate of the lamina propria was composed of both B lymphocytes and T lymphocytes.

Antigens↗