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L Kater

Publications and source records attributed to L Kater.

At least 73 records · Page 4Linked to original sources
PubMed1986

Characteristics of IgA deposits in liver and skin of patients with liver disease.

The presence of IgA deposits in a continuous pattern along hepatic sinusoids is a specific entity for alcoholic liver disease. In superficial skin blood vessels of patients with liver disease, IgA deposits can occur. The authors characterized the deposits for IgA-subclass epitope expression and for macromolecular configuration (assessment of [hidden] J-chain determinants and of secretory component-binding capacity). A variety of monoclonal anti-IgA-subclass reagents were applied, which proved to be specific in control experiments on blastoid cells generated by pokeweed mitogen stimulation of blood mononuclear cells and frozen tissue sections of normal jejunum. IgA1 is the major component in IgA deposits in liver (n = 83) and skin (n = 31) of patients with liver disease. Macromolecular IgA is detectable in only one-fifth of the cases. The authors' data do not indicate that hepatic IgA deposits in liver disease are of gastrointestinal origin. Out of the circulating IgA pool, IgA1 appears to be most capable of being deposited in tissue.

Histocytochemistry↗
PubMed1986

Familial Cushing's syndrome due to nodular adrenocortical dysplasia. A putative receptor-antibody disease?

Two sisters aged 13 and 19 years suffering from familial Cushing's syndrome due to nodular adrenocortical dysplasia are described. Pituitary adrenocortical function tests indicated the presence of adrenal autonomy. Adrenal scintigraphy showed bilateral symmetrical uptake indicating the bilateral character of the autonomous process. Complete adrenalectomy was performed in both girls. The adrenals were of about normal weight showing numerous dark brown pigmented nodules and small perivascular lymphocytic infiltrates. Serum immunoglobulin preparations obtained from both girls stimulated adrenocortical cell growth in a cytochemical bioassay system. It is proposed that circulating growth factors may be involved in the pathogenesis of the disease.

Adolescent↗
PubMed1986

Morphometric study of histological changes in sublabial salivary glands due to aging process.

The sublabial salivary glands were studied by morphometric methods in 68 healthy volunteers to establish possible changes related to age in those tissue components that are affected in Sjögren's syndrome and connective tissue diseases (and which might stimulate Sjögren's syndrome). There was an increase in the amount of connective tissue and intralobular ducts with age and a corresponding decrease in acinar tissue. During the aging process changes in the intralobular ducts occurred: the outer and inner diameters of these ducts and the thickness of the epithelium decreased, but the ratio of the outer and inner diameters of the ducts remained constant. The amount of diffuse lymphoplasmacytic infiltrate and the vascularity of the tissue remains constant with age. In 15 of the subjects, however, discrete lymphocytic foci were seen and in six of these more than one focus/4 mm2 of salivary tissue was found, which has been described as suggestive of Sjögren's syndrome. The volume percentage of lymphocytic foci is constant during the aging process. The histological features commonly used to diagnose Sjögren's syndrome may occur in normal people, and false positive diagnoses will occur if these criteria are rigidly adhered to. Morphometry may provide more reliable criteria for distinguishing changes induced by inflammation and related to age which occur in salivary tissue.

Adolescent↗
PubMed1986

Presence of oestrogen receptors in human blood mononuclear cells and thymocytes.

We studied oestrogen binding sites in blood mononuclear cells from healthy blood donors, patients with leukaemia or systemic lupus erythematosus, and in thymocytes, using the dextran-coated charcoal assay and Scatchard analysis of binding data. Using 3H-labelled oestradiol as ligand, inaccurate results were obtained which could be related to the low amounts of binding sites. Using 125I-labelled ligand, saturable oestradiol binding sites could be demonstrated in low amount (mean value 2.1 fmol/mg of cytosolic protein) and high affinity (mean Kd value 0.26 nM; mean Ka value 3.85 X 10(9) M-1). The binding could be inhibited by unlabelled oestradiol but not with oestrone, dihydrotestosterone, cortisol and the progestin-receptor ligand Org 2058. We conclude that blood mononuclear cells and thymocytes contain true oestrogen receptors. This conclusion supports current hypotheses on the involvement of such receptors in oestrogen-mediated modulation of the immune system.

Adult↗
PubMed1986

The association between the lupus anticoagulant and cerebral infarction in systemic lupus erythematosus.

The lupus anticoagulant (LAC) is associated with the occurrence of thromboembolic complications. Assuming that thrombosis may underlie manifestations of the central nervous system (CNS) in patients with systemic lupus erythematosus (SLE), we studied 20 patients with SLE and CNS manifestations for the presence of LAC. In 8 patients (40%) including 4 with overt cerebral infarction, LAC was demonstrated. The 4 patients with LAC and cerebral infarction all had thrombocytopenia, 2 had a history of peripheral thrombosis, and one recurrent abortion. In the 4 LAC-positive patients without overt cerebral infarction, thrombocytopenia was present in 3, a history of thrombosis in 2, and fetal wastage in one. We conclude that LAC identifies within the CNS-SLE group a subpopulation of patients in whom CNS manifestations are caused by cerebral infarction. This subpopulation is further characterized by increased prevalence of thrombocytopenia, peripheral thrombosis and fetal wastage. A possible pathogenetic role of LAC may be related to a hypercoagulable state occurring in this subgroup of SLE patients.

Adolescent↗
PubMed1986

Implantation of cultured thymic fragments in patients with acquired immunodeficiency syndrome.

Cultured thymic fragments were implanted in one patient with acquired immunodeficiency syndrome (AIDS)-related complex (ARC) and in eight AIDS patients with opportunistic infections (OIs, four patients), Kaposi's sarcoma (KS, two patients), or both (two patients). Thereafter, objective clinical improvement was noted in one patient with OI, and a stable symptom-free condition was observed in the ARC patient and in two other patients with OIs. However, the ARC patient and two of the three patients with OIs developed infections three to six months after implantation. A fourth case of OI and the patients with KS showed progression of the disease. Peripheral blood investigations for counts of total leukocytes, lymphocytes, and T-lymphocyte subsets as well as for lymphocyte stimulation with mitogens showed no changes interpretable as an improvement of the cellular immune deficiency status. We conclude that cultured thymic fragments have no distinct in vivo effect on the course of AIDS, except for a temporary clinical improvement or a period of stable condition in some patients with OIs.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Cultured human thymus epithelial monolayer cells induce CD4 expression on mononuclear cells of AIDS patients in vitro.

We investigated the in vitro effect of cultured human thymic epithelial monolayer cells on mononuclear cells (MNC) from patients with Acquired Immune Deficiency Syndrome (AIDS) and AIDS-related complex (ARC). Patients having undergone bone-marrow transplantation (BMT), who showed a similar deficiency of T-lymphocytes expressing CD4 (Leu-3, T4), and healthy blood donors served as controls. Most epithelial monolayer cells were of thymic medulla origin, as documented using a panel of monoclonal antibodies to thymic epithelial cells. In AIDS/ARC patients the CD4-positive cells (ranging between 4 and 30% of MNC) increased by a factor of 1.56 (s.e.m. 0.15, n = 12) during a 2 h incubation on the monolayer. Human fetal lung fibroblasts were inactive in this respect. There was no consistent change in cells expressing CD3 (Leu-4, T3), CD5 (Leu-1) or CD8 (Leu-2, T8). In BMT patients and healthy controls, neither thymus epithelium nor fibroblasts had any effect on T cell marker expression. Incorporation of tritiated thymidine by stimulated or unstimulated lymphocytes was increased after incubation for 3 days on either epithelium or fibroblasts. We conclude that CD4 expression is induced on MNC from AIDS/ARC patients during a 2 h incubation on epithelial monolayers.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Morphometry in the diagnosis of Sjögren's syndrome.

Sublabial salivary gland biopsies of 20 patients with Sjögren's syndrome and 58 controls were analyzed morphometrically to determine which histologic changes in the tissue are specific enough to justify a diagnosis of Sjögren's syndrome and which changes are due to physiologic aging. The acinar atrophy, fibrosis, ductal hyperplasia and ductal dilatation mentioned in the literature as features of Sjögren's syndrome are also observed in the tissue of aging individuals, and the lymphocytic focus score cited as the most important diagnostic parameter gives rise to about 9% of false-positive diagnoses. When using single quantitative histologic parameters, the volume percentages (Vol%) of lymphocytic foci, diffuse lymphoplasmacytic infiltrate (DLPI), acini and the inner diameter of intralobular ducts (ILD) were able to discern between the patients and the controls at a significant level, regardless of age, although considerable overlap was still present. This overlap could be reduced by consideration of at least two histologic parameters. The inhomogeneity within the tissue constituents was also used in discriminating between the patients and the control subjects. The best bivariate discriminating combination of histologic parameters was Vol% of lymphocytic foci and DLPI. Compared with qualitative subjective evaluation, this morphometric decision rule in the present material gave a 5 X reduction in the number of false-positive diagnoses of Sjögren's syndrome, with only 1 of the 58 control subjects erroneously classified as having the syndrome. We conclude that quantitative investigation of sublabial salivary gland tissue will improve the diagnostic criteria needed for the definition of Sjögren's syndrome.

Adult↗
PubMed1986

Large vessel occlusion and gangrene in systemic lupus erythematosus and "lupus-like" disease. A report of six cases.

Six patients are presented, all of whom had systemic lupus erythematosus or a "lupus-like" disease and who developed major thromboses with gangrene of the extremities. Four of the 6 patients had circulating antiphospholipid antibodies at some point during the course of their illness. These serological markers, which have been associated with a tendency to thrombosis, may have contributed to the development of gangrene in these patients. Histological examination of affected arteries in 4 patients did not show any evidence of vasculitis. One patient in whom antiphospholipid antibodies were negative showed healing vasculitis on histology.

Adult↗
PubMed1985

Lymphocyte status of lymph node and blood in acquired immunodeficiency syndrome (AIDS) and AIDS-related complex disease.

Blood lymphocytes and lymph nodes from three patients with acquired immunodeficiency syndrome (AIDS) and two cases with AIDS-related complex (ARC) were studied during the course of the disease. The lymph node histomorphology could be grossly categorized into three stages: follicle hyperplasia, follicle degeneration and the depleted stage. In the first stage, follicles show large and sometimes irregular-sized germinal centres and narrow B-cell mantles. Dendritic reticulum cells in the germinal centres reveal disruption of their fine dendritic processes; often indentations are visible, filled with small B- and T-lymphocytes of follicle mantle and paracortical origin. These lesions may be the first signs of follicle degeneration, in which only hyalinized remnants of follicle centres are found. The changes in the paracortex are less prominent than those in the follicles. The disturbance in the numerical balance of T-cell subsets of helper-induced and suppressor-cytotoxic phenotypes is less than that found in the blood. In some cases the paracortex reveals a high density of T6-positive elements resembling interdigitating cells, suggestive of continuous antigen exposure. We found follicle hyperplasia in ARC, follicle degeneration in one case of ARC and in full-blown AIDS, while the depleted stage was found in lymph nodes at autopsy of AIDS patients. Lymph node changes do not completely correlate with the changes in the blood lymphocyte pool. Investigations on lymph nodes may be of value in the assessment of the prognosis of the disease.

Acquired Immunodeficiency Syndrome↗
PubMed1985

The thymus in "bare lymphocyte" syndrome: significance of expression of major histocompatibility complex antigens on thymic epithelial cells in intrathymic T-cell maturation.

Thymic biopsies from two patients with combined immunodeficiency and defective expression of HLA class I and class II antigens on blood mononuclear cells ("bare lymphocyte" syndrome) were investigated. This made possible an evaluation of the significance of HLA antigen expression in a detailed (immuno)histologic study. Both thymuses showed a normal lobular architecture with distinct cortex-medulla areas, well-differentiated epithelium, including ultrastructurally defined subtypes, and Hassall's corpuscles. Normal numbers of lymphoid cells were present and normal T-cell phenotype was found. Using anti-HLA-A,B,C antisera, confluent staining of the medulla (stroma and lymphocytes) was observed. One of the thymuses was found to be negative for HLA class II antigen expression: the other revealed only HLA-DR positivity of nonlymphoid cells in the medulla. These cells were not of epithelial nature as judged from double staining with anti-keratin antibody. There was no expression of HLA-DC/DS. These observations differ from findings in the normal thymus, wherein epithelial cells in the cortex carry HLA class I and class II antigens, and epithelial cells in the medulla express HLA class I, and for a minor part class II antigens. The results indicate a normal sequential acquisition of T-cell differentiation antigens in the thymus of both cases. It is suggested that the expression of HLA class I and class II antigens on epithelial cells in the normal thymus cortex does not play a significant role in the sequential acquisition of differentiation antigens on T lymphocytes.

Antigens, Surface↗
PubMed1985

HNK-1+ cells in non-Hodgkin's lymphoma: lack of relation with transferrin receptor expression on malignant cells.

It has been proposed that Natural Killer (NK) cell activity is involved in host defence against neoplasia, and that NK cells react with or recognize the transferrin receptor (TrR) on target cells. HNK-1 expression has been related to NK cell function. Therefore, in 118 cases of non-Hodgkin's lymphoma (NHL) we studied the occurrence and distribution of HNK-1+ cells by immunohistochemistry, and simultaneously assessed the expression of TrR on malignant cells. In NHL of intermediate or high grade malignancy there was uniform expression of TrR on malignant cells. In low grade malignancy NHL, only lymphocytic and lymphoplasmacytoid lymphomas were TrR negative, except for faint staining of proliferation centres. In 23 cases of follicular lymphoma, 9 showed the absence of HNK-1+ cells in neoplastic follicles. In 16/23 cases HNK-1+ cells were present around follicles or in interfollicular areas: 8 of these cases revealed a higher density of HNK-1+ cells at this site than inside the follicles. In 22/26 cases with high grade malignancy NHL, HNK-1+ cells were absent or present in small density, which is different from the presence in higher density in low grade malignancy NHL. We conclude that (i) TrR expression on NHL cells is not obligatory related with histological class or malignancy grade of the tumour, and that (ii) HNK-1+ cells are not universally present in areas of malignant cells, in particular in follicular lymphoma and in NHL of high grade malignancy.

Antibodies, Monoclonal↗