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Biomedical subjects

L Kater

Publications and source records attributed to L Kater.

At least 127 records · Page 7Linked to original sources
PubMed1979

Presence of thymosin-like factors in human thymic epithelium conditioned medium.

The objective of the present study was to determine whether or not thymosin and conditioned medium from human thymus epithelial cultures (HTECM) contain similar fractions, capable of inducing T-cell differentiation. Therefore we tested the ability of rabbit antisera to different thymosin fractions (thymosin fractions 5, 6 and alpha 1) of both bovine and human origin to block the stimulatory effect of HTECM on Con A and PHA response of mouse thymocytes. We also looked for reactivity of the antisera toward tissues of man, mouse and calf, and to tissue cultures of man and mouse. Anti-thymosin fraction 5 and 6, but not anti-thymosin-alpha 1, were found to inhibit the stimulatory effect of HTECM on both Con A and PHA responses. This cannot be attributed to cytostatic or cytotoxic effects of the antisera on thymocytes. No effect was seen when using antiserum to kidney fraction 5 or normal rabbit serum. In both tissue sections and tissue cultures of the different species tested, anti-thymosin reacts only with thymus epithelial cells. The reactivity is blocked by neutralizing the antisera with thymosin fraction 5 but not by kidney fraction 5. The reactivity is also strongly diminished by neutralizing the antisera with HTECM but not with supernatants of conditioned media from non-thymic tissues. The observations are highly suggestive for the presence of similar fractions in HTECM and thymosin, and that both are secreted by thymus epithelial cells.

Animals↗
PubMed1979

Alcoholic hepatic disease. Specificity of IgA deposits in liver.

The extent to which the immunofluorescent phenomenon of homogeneous deposition of IgA in the hepatic sinusoids (so-called continuous pattern) was specific for alcoholic hepatic disease was investigated. In 66 of 320 liver biopsy specimens a continuous IgA pattern was observed. Alcoholism was mentioned in the cases of 50 of the 66 patients (76%). The biopsy specimens in the remaining 254 cases continued scanty detectable IgA (discontinuous pattern) or none. In the latter group only eight patients (3%) had histories of alcoholism. A direct correlation between a continuous IgA pattern in the hepatic sinusoids and alcohol abuse is thus inferred (P less than 0.001). Additional findings of the concomitant occurrence of IgA in the perisinusoidal linings of the liver, the wall of superficial cutaneous capillaries, capillaries of the gut, and the glomerular mesangium in association with alcoholic hepatic disease further substantiates the concept of the existence of an IgA-associated disease.

Antibody Specificity↗
PubMed1979

Plasma exchange in immune complex disease.

The effect of plasma exchange on CIC, anti-dsDNA and complement levels and clinical activity was studied in eight patients with SLE, one with idiopathic anaphylactoid purpura and one with mixed cryoglobulinaemia. No association existed between different tests for immune complex detection. Plasma exchange as sole therapy was effective in patients with idiopathic anaphylactoid purpura and mixed cryoglobulinaemia, but not in one SLE patient with CIC. Five SLE patients with CIC treated with corticosteroids showed improvement on plasma exchange but in two patients with and two with CIC plasma exchange was not effective.

Adolescent↗
PubMed1978

Production and traffic of B lymphocytes in the extracortical central area of the guinea pig thymus.

Lymphocytes in the stroma and lymphatics of the extra-cortical central area (ECCA) of the guinea pig thymus have been studied with light microscopy, quantitative microscopy, colchicin-induced mitotic arrest, EA (IgG) and EA (IgM) C adherence, surface immunoglobulins (Ig total, IgM, IgG), alkaline phosphatase activity and the effect of cyclophosphamide administration. The results suggest, that AP-positive, SIg-positive EAC-negative lymphocytes in the ECCA proliferate and maturate into AP-negative, SIg-positive, EAC-positive lymphocytes. The latter leave the thymus through the lymphatics. Calculations show that daily 8-9 X 10(6) B lymphocytes are produced in the ECCA and leave this area through the lymphatics. As this number is more than 10% of the number of T cells which daily leave the thymus, we conclude that in the ECCA a considerable number of B lymphocytes is produced.

Alkaline Phosphatase↗
PubMed1978

Experiences with thymosin in primary immunodeficiency disease.

Thymosin has no effect in vitro on cyclic AMP levels in thymocytes. However, when thymosin was injected into patients lacking "serum factor" (SF) activity, it induced the appearance of SF or SF-like activity and the disappearance of target cells for SF among the peripheral blood lymphocytes of the treated patients. On the other hand, when thymosin was injected into one patient with normal SF activity, it induced a marked decrease of SF activity and the appearance of target cells for SF among the peripheral blood lymphocytes of this particular patient.

Animals↗
PubMed1976

Occurrence of vascular IgA deposits in clinically normal skin of patients with renal disease.

Skin and kidney biopsies were performed on 262 patients with various nephropathies. In 45 skin biopsy specimens finely granular deposits of predominantly IgA and late-acting complement factors were detected in the walls of superficial capillaries, sometimes concomitantly with IgM, IgG, C4 or a combination of these proteins. Twelve of the 45 patients presented with anaphylactoid purpura and the majority of the other 33 patients had either recurrent macroscopic or microscopic hematuria. The renal lesions in 32 of these 45 patients consisted of focal segmental intracapillary proliferation. In 35 the kidney biopsy specimen showed mesangial deposits of IgA; in one case IgA was deposited along the glomerular basement membrane. In only three of the remaining 217 patients without cutaneous IgA deposits were typical mesangial IgA deposits found. The close correlation between IgA deposits in cutaneous vessels and focal segmental intracapillary proliferation with mesangial IgA deposits suggests that immunofluorescence examination of skin biopsy specimens could prove of diagnostic value. The results provide additional evidence for a close pathogenic relationship between IgA-associated glomerulonephritis and anaphylactoid purpura.

Adult↗
PubMed1976

Significance of anti-HBc in patients with hepatic disease. A comparative immunohistochemical study of blood and hepatic tissue.

Use of the immunofluorescent technic to examine liver sections disclosed different staining patterns for HBsAg and anti-HBc. In reverse, anti-HBc in serum can be detected by immunofluorescence using HBc-positive liver sections as substrate. In 57 of 89 sera tested, anti-HBc could be observed using immunofluorescence. Of these 57 sera, 31 contained HBsAg (54.5%), 15 contained anti-HBs (26.3%), and one contained both HBsAg and anti-HBs (1.7%). Ten patients (17.5%) had anti-HBc without HBsAg or anti-HBs; nine of these patients had disturbed hepatic functions. In eight cases biopsies of liver tissue showed lesions varying from steatosis to cirrhosis. In 32 anti-HBc-negative sera no HBsAg was found; transient anti-HBs was found in one case and persistent anti-HBs was also seen in one case. Biopsies of the livers of 27 anti-HBc-positive patients disclosed the whole spectrum of histologic lesions. There appear to be correlations between HBsAg in blood and in liver, and also between nuclear IgG, the HBsAg pattern in hepatic tissue, and active hepatic disease.

Antibodies, Viral↗
PubMed1976

B lymphocytes in the guinea pig thymus are specifically localized in the central area.

Since the central area is an integral part of the guinea pig thymus, the cells in this area were compared with those in the thymic cortex and medulla in cryostat-sections by using methods for demonstration of E-, EA-, EAC-adherence and surface membrane immunoglobulins. In the extra cortical central area (ECCA) 15 to 25% of the lymphocytes showed EAC-adherence and 5 to 10% appeared to bear surface membrane immunoglobulins (SIg). In the lymph sinuses up to 70% of the lymphocytes were EAC- and SIg-positive. A small amount of EAC-adhering cells was present in the medulla of the central area. Cortical lymphocytes were EAC- and SIg-negative. From these results we conclude that in the guinea pig thymus B lymphocytes are specifically localized in the central area.

Animals↗
PubMed1976

Immunofluorescent localization of factor VIII-related antigen, fibrinogen, and several other plasma proteins in hemostatic plugs in humans.

Factor VIII-related antigen and its low ionic strength subunits were demonstrated in endothelium and hemostatic plugs obtained from punch biopsies of bleeding time wounds according to Mielke. No IgG, IgA, IgM, C4-C3, albumin, or prothrombin was demonstrated in the cryostat sections of hemostatic plugs. Antifibrinogen stained the hemostatic plug and fibrin fibers along the edges of the skin wound. Antiplatelet actomyosin stained the hemostatic plug and the endothelium and pericytes of blood vessels. These results suggest that factor VIII is present in the hemostatic plug not by trapping of plasma but by close association with or presence within the blood platelets. The positive staining of a hemostatic plug in which most platelets have undergone the release reaction indicates that antifactor VIII may be useful for the detection of platelet thrombi in tissue of patients with suspected diffuse intravascular coagulation.

Albumins↗