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M M Wilders

Publications and source records attributed to M M Wilders.

10 recordsLinked to original sources
PubMed1985

Veiled cells in the gastrointestinal tract.

Lately it has become known that for the initiation of an immune response an antigen presenting cell is needed. In the skin the antigen presenting cell system has been studied and is extensively supposed to consist of Langerhans' cells in the epidermis and dermis, veiled cells in the skin lymph, and interdigitating cells in the skin lymph nodes. These cells are considered to belong to the mononuclear phagocyte system which is in principle composed of cells stemming from the promonocyte/monocyte. To detect whether an antigen presenting cell system is present in the gut, we studied cell suspensions of gut tissues. Monoclonal cells with long actively moving cytoplasmic veils were found in cell suspensions from small intestinal villi of guinea pig and pig, but not of rat. These veiled cells appeared to be strongly Ia positive, as are the cells from the skin antigen presenting system. They share several ultrastructural and enzyme cytochemical characteristics with these skin cells. Gut veiled cells localize within the lympho-epithelium of Peyer's patches of the rat, just underneath this lympho-epithelium and in the T-dependent interfollicular area, according to Ia stainings on frozen tissue sections and to ultrastructural observations. From stainings with anti-IgA, -IgE, -IgG, -IgM and anti-T lymphocyte sera it is concluded that these cells do not belong to the lymphocyte series. It is suggested that these gut veiled cells belong to the monocyte/macrophage family and form an antigen presenting cell system in mucosa-associated lymphoid tissue, similar to the antigen presenting cell system in the skin.

Animals↗
PubMed1984

Peripolesis followed by cytotoxicity in chronic idiopathic inflammatory bowel disease.

Antigen presenting veiled cells have recently been described in cell suspensions prepared from the gut wall of patients with chronic idiopathic inflammatory bowel disease (CIBD). The normal gut wall is virtually devoid of these cells. In this report we describe a phenomenon known as peripolesis studied by phase contrast cinematography. This is a process in which lymphocytes are seen to wander around larger target cells. These could be identified ultrastructurally as Ia positive veiled cells. In most cases peripolesis was followed by lysis of the target cell. Peripolesis was recorded in cell suspensions of three out of seven patients with ulcerative colitis and in three out of nine patients with Crohn's disease; furthermore peripolesis was observed in one out of two patients with non-classifiable CIBD. In four cell suspensions showing peripolesis, cell lysis could be recorded and was especially striking in ulcerative colitis. Peripolesis involving veiled cells was previously described in delayed hypersensitivity reactions. This study lends support to the concept that delayed allergic reactivity plays a part in chronic inflammatory bowel disease. The antigens involved are, however, completely unknown.

Adolescent↗
PubMed1984

Veiled cells in chronic idiopathic inflammatory bowel disease.

The mononuclear cell system in the human gut wall of patients with Crohn's disease (CD), ulcerative colitis (UC) and normal controls was studied, with special reference to the so called antigen presenting veiled cells. These cells have already extensively been studied in the skin and are known as Langerhans' cells in the epidermis and dermis, veiled cells in the skin lymph and interdigitating cells in lymph nodes. Recently they were also found in gut associated lymphoid tissue, i.e. Peyer's patches of the rat. Here we describe the presence of similar cells in chronic idiopathic inflammatory bowel disease (CIBD). They resemble veiled cells in moving pattern, strong Ia positivity, no or only weak acid phosphatase activity, and ultrastructure. However, many of the described cells combine these characteristics with those of phagocytic macrophages. In the gut wall of controls veiled cells were virtually absent and phagocytic macrophages were almost exclusively recognized. These findings suggest that more intensive antigen handling takes place in the gut wall of CIBD patients than in normal gut. Clear cut associations with sex, age, duration or activity of disease were not observed in this limited study, and the exact significance of the presence of such cells needs further clarification.

Acid Phosphatase↗
PubMed1983

Characterization of non-lymphoid cells in Peyer's patches of the rat.

The aim of the present study was to correlate in vitro and in situ observations on nonlymphoid cells in Peyer's patches (PP) of the rat. By carrying out enzyme cytochemical reactions (acid phosphatase, APh, and non-specific esterase, NSE) and immunocytochemistry (Ia antigen staining) on cell suspensions and cryostat sections of PP, two classes of nonlymphoid cells could be distinguished. These were (1) strongly APh- and NSE-positive cells without or with a slight Ia membrane staining and (2) strongly Ia-positive cells with a weak APh and NSE activity. The first cell class comprised the classical macrophages which, except for tingible body macrophages, were glass-adherent. The second cell class was non-adherent and comprised dendritic (interdigitating) cells. The role of this Ia-positive non-adherent cell population was discussed, and a hypothesis was presented on the relation between mononuclear blood cells, veiled cells, and interdigitating cells in PP.

Acid Phosphatase↗
PubMed1983

Large mononuclear Ia-positive veiled cells in Peyer's patches. II. Localization in rat Peyer's patches.

Dendritic Ia-positive veiled cells were seen in frozen sections of rat Peyer's patches within the lymphoepithelium, in the reticular area just underneath and in the T-dependent interfollicular area. From immunohistochemical stainings with anti-IgA, IgE, IgG, IgM and monoclonal anti T lymphocyte sera it is concluded that these Ia-positive cells do not belong to lymphocyte series. The ultrastructure of these Ia-positive veiled cells resembled the morphology of the veiled cells found in Peyer's patch cell suspensions and in skin lymph. It is suggested that these cells form an antigen presenting cell system in mucosa-associated lymphoid tissue, similar to the antigen presenting cell system in the skin.

Animals↗
PubMed1983

Large mononuclear Ia-positive veiled cells in Peyer's patches. I. Isolation and characterization in rat, guinea-pig and pig.

The antigen presenting cell system in the skin is extensively studied, and is supposed to consist of Langerhans cells in epidermis and dermis, veiled cells in skin lymph and interdigitating cells in skin lymph nodes. In order to detect whether a similar cell system is present in the gut, we studied Peyer's patch cell suspensions. Mononuclear cells with long actively moving cytoplasmic veils were found in cell suspensions from Peyer's patches of rat, guinea-pig, and pig, and in cell suspensions from small intestinal villi of guinea-pig and pig, but not of rat. These veiled cells are strongly Ia-positive. Because of their Ia positivity, their enzyme cytochemical staining pattern, and their ultrastructure, these cells resemble the antigen presenting cells of the skin, skin lymph and lymph node.

Animals↗
PubMed1983

Ontogeny of non-lymphoid and lymphoid cells in the rat gut with special reference to large mononuclear Ia-positive dendritic cells.

The ontogeny of rat Peyer's patches was studied with special reference to Ia-positive dendritic cells. The 16-day-old foetus contained large Ia-positive dendritic cells randomly distributed throughout the gut wall and mesentery. In cell suspensions prepared from the foetal gut, these cells showed the typical movement pattern of veiled cells, and they shared ultrastructural features with these and other antigen-presenting cells. The gut was found to be the first organ in which large numbers of these Ia-positive dendritic cells were found. At 16 days gestation, the Ia-positive dendritic cells were randomly distributed throughout the primitive gut wall, but at later stages accumulated in structures which were clearly recognizable as Peyer's patches from 20 days gestation onwards. T and B lymphocytes could be seen on the day of birth at the earliest, at first randomly distributed throughout the Peyer's patch, but afterwards concentrating in separate T- and B-cell regions. Two weeks after birth Peyer's patches consisted of densely populated B-cell nodules, mainly comprising surface IgM (sIgM) positive cells, and internodular T-cell regions. Ia-positive dendritic cells were situated between the epithelial cells of the dome area, just underneath this epithelium in a loose reticular area and in the internodular T-cell regions. These Ia-positive dendritic cells were acid phosphatase negative or only weakly positive. Some Ia-positive dendritic cells were also present in small intestinal villi at all ages studied. However, these cells started to express an increasing acid phosphatase activity in the 2 weeks following birth. Thus they resemble macrophages, while Peyer's patch dendritic cells show characteristics of antigen-presenting cells.

Animals↗
PubMed1982

Antigen-trapping cells in Peyer's patches of the rat.

Peyer's patches (PP) of rats were studied with immunocytochemical, enzyme cytochemical, and electron microscopic techniques. Special attention was paid to the non-lymphoid antigen-trapping cells. Follicular dendritic cells, morphologically comparable to those present in spleen and lymph nodes, were found in the germinal centers of PP. Ia-positive cells with the morphological characteristics of interdigitating cells were seen in the interfollicular area. Thus, both types of antigen-presenting cells, characteristic for B- and T-cell areas, respectively, were present in PP.

Animals↗