Hodgkin's cells express CD83, a dendritic cell lineage associated antigen.

Hodgkin's cells (HC) are considered to be the malignant cells of Hodgkin's disease (HD), but despite extensive studies, no conclusive evidence has emerged regarding their non-malignant counterpart and the ontogeny of these cells remains controversial. The analysis of a possible dendritic cell (DC) origin of HC has been hampered to date by the lack of a DC lineage specific marker. The expression of the two DC-associated antigens CD83 and CMRF-44, the B lymphocyte restricted molecule CD79, and the costimulator molecule CD86, was examined in lymph nodes from 23 HD patients using immunohistological techniques. The majority of HC expressed the CD83 (22/23) and CD86 antigens (20/23), whereas expression of the CMRF-44 antigen was variable (10/23) and usually only a subpopulation of HC stained. In contrast, the CD79 antigen was absent from most HC (17/23). The presence of the CD83 antigen on HC in the absence of the CD79 antigen supports a possible DC lineage origin for some HC. Regardless of its role in lineage assignment, CD83 may become a useful immunohistological marker for HD as the CD83 antigen was present on most HC.

Comparison of histological and biochemical hepatic iron indexes in the diagnosis of genetic haemochromatosis.

AIMS: To compare a histological hepatic iron index with a biochemical hepatic iron index, derived from atomic absorption spectroscopy measurements of hepatic iron content, for the diagnosis of genetic haemochromatosis (GH). METHODS: Histological sections of liver biopsy specimens from 70 subjects, who had previously had their biochemical hepatic iron index measured, were examined. The iron stores were scored to derive a histological hepatic iron index and were also graded from 0 to 4 by a standard grading system. The case history of each patient was then reviewed to establish a definitive clinical diagnosis and patients were classified as GH, non-GH or indeterminate. RESULTS: There were 26 cases of GH, 40 cases of non-GH and four indeterminate cases in whom a definite clinical diagnosis was not established. Using a biochemical hepatic iron index cut off level of 2.0, two cases were misclassified, with one case of GH having a biochemical hepatic iron index of 1.8 and one non-GH case having a biochemical hepatic iron index of 3.1. This could not have been improved by altering the cut off level. Using the recommended cut off level of 0.15, the histological hepatic iron index was raised in all cases of GH, but was also increased in 11 of the 40 non-GH patients. The specificity of this histological index can be improved by increasing the cut off level to 0.30. A histological iron grade of > or = 3 is more specific than the histological index but has a lower sensitivity, which particularly affects the diagnosis of younger patients with GH. CONCLUSIONS: The biochemical hepatic iron index is a reliable method for establishing a diagnosis of homozygous GH. In contrast, the histological hepatic iron index as originally described is non-specific and does not reliably distinguish patients with GH from others with a raised hepatic iron index due to other causes. The specificity of this index can be improved by increasing the cut off level used, but the discrimination provided by the histological index is still inferior to that provided by the biochemical hepatic iron index.

Acute adrenal insufficiency: a new presentation of Castleman's disease.

We report the case of a 35-year-old patient who presented with acute adrenal insufficiency, then developed fever, hypoalbuminuria, anasarca, thrombocytopaenia and anaemia. Lymphadenopathy appeared later with microscopic features typical of Castleman's disease. Clinical remission followed treatment with intravenous immunoglobulin. Circulating interleukin-6 levels were elevated initially but were normal after immunoglobulin therapy. We surmise that high circulating levels of interleukin-6 (and ACTH) may have induced haemorrhagic necrosis of the adrenal glands and accounted for the constitutional symptoms.

Hodgkin's cells express a novel pattern of adhesion molecules.

Adhesion molecules play an important role in the functioning of the immune system, particularly with regard to cell-cell interactions and antigen presentation. Several adhesion molecules are expressed on Hodgkin's disease-derived cell lines and these are important in their molecular interactions as antigen presenting cells (APC). There are no data regarding the expression of many of these adhesion molecules on Reed-Sternberg cells and its mononuclear variant (Hodgkin's cells (HC)) present in pathological material. To obtain this information we undertook an immunohistological study on material from 18 cases of Hodgkin's disease using a panel of MoAbs to examine the expression of adhesion molecules on HC. The HC were shown to express the integrin beta 1 subfamily molecules, LFA-1 (CD11a) and p150,95 (CD11c) in high density but lacked CR3 (CD11b). All of the immunoglobulin gene superfamily adhesion molecules studied were present to some degree on HC, with ICAM-2, in particular, showing moderate to strong expression in most cases. The Hermes antigen CD44 was present in high density but leukosialin (CD43), another molecule present on diverse leucocyte types, was, in general, not detected on HC. These new data showing that ICAM-1, ICAM-2 and LFA-3 are, like LFA-1, expressed on HC emphasize the ability of HC to act as APC. The known adhesion molecule phenotype of the recently defined haematopoietic lineage of human dendritic cells (DC) is broadly similar to that of HC, perhaps supporting the hypothesis that some HC represent a malignancy of an APC (DC) lineage.

Nodular sclerosing, mixed cellularity and lymphocyte-depleted variants of Hodgkin's disease are probable dendritic cell malignancies.

The normal counterpart of the Reed-Sternberg cell and its mononuclear variant, collectively referred to as Hodgkin's cells (HC), remains controversial. The possibility that HC are malignant dendritic cells was tested by using a panel of 38 monoclonal antibodies to phenotype the cells from 16 cases of Hodgkin's disease (HD), excluding lymphocyte-predominant HD, and the Hodgkin's cell line L428. The results were then compared with the known phenotype of human dendritic cells. HC stained strongly for HLA Class I and Class II antigens. The leucocyte common antigen was weakly expressed in most cases. Expression of T and B cell markers was unusual, with the exception of the CD40 antigen which was found on a majority of HC. HC commonly expressed the CD11a, CR4 (CD11c), CD15, CD18 and a number of activation antigens but did not stain with a variety of macrophage-specific antibodies. The antigenic phenotype of L428 and the HC of case material were similar. This immunocytological analysis failed to support a lymphocyte or macrophage origin for HC. Instead the antigenic phenotype of the Reed-Sternberg cell and its mononuclear variant more closely resembles that of dendritic cells than of any other haemopoietic cell normally resident in lymph nodes.

Defenestration of hepatic sinusoids as a cause of hyperlipoproteinaemia in alcoholics.

The hepatic sinusoidal endothelium separates sinusoidal blood from hepatocytes; changes in the porosity of this endothelium may affect the passage of chylomicrons into hepatocytes and influence lipid metabolism. Chronic exposure to ethanol reduces the porosity of the endothelium; this mechanism may underlie the hyperlipoproteinaemia observed in some people who drink heavily.

Intestinal anisakiasis: a new New Zealand disease.

Anisakiasis is not an uncommon disease in countries where raw fish is a delicacy. This example of intestinal obstruction following reaction to a migrating anisakis larva is the first case reported in New Zealand.

Primary sclerosing cholangitis.

Six patients with primary sclerosing cholangitis are described. It is an uncommon disease of uncertain aetiology following an unpredictable course but often progresses to secondary biliary cirrhosis, portal hypertension, and premature death from liver failure. Ulcerative colitis is commonly associated with primary sclerosing cholangitis. Endoscopic retrograde cholangiography is the investigation of choice. Liver biopsy may support the diagnosis but is not pathognomonic. There is no effective treatment but symptoms may be controlled.