Plasma cell tumours of the mastoid are rare malignancies of haematological origin. Two patients are described with a plasma cell tumour in the mastoid bone. In one patient it concerned a solitary ...plasmacytoma of the bone and in the other a focus in the mastoid of a recently diagnosed multiple myeloma. Symptoms in these patients were non-specific. Computed tomography (CT) and magnetic resonance image (MRI) scanning showed a non-specific space-occupying lesion in the mastoid. The diagnosis was made on immunohistological examination, that showed diffuse sheets of monoclonal plasma cells in a clear matrix. When a plasmacytoma lesion is found multiple myeloma should always be excluded. Treatment in case of solitary plasmacytoma of the mastoid bone consists of radiotherapy. In case of localization in the mastoid of multiple myeloma the treatment consists of palliative chemotherapy.
Flounder taken from The Netherlands coast and estuaries had high incidence of lesions of the liver and lymphocystis virus. To elucidate the cause of these conditions, flounder were exposed oral doses ...of TCDD or extract of harbor sludge, followed by histopathological examination of several tissues. Cytochrome P4501A (CYP1A) induction, visualization of proliferation of hepatocytes, and thymus size were also monitored. After eight weeks of exposure to either substance increased CYP1A immunoreactivity in hepatocytes. Exposure to high doses of TCDD was associated with increases of endothelial CYP1A immunoreactivity in almost all organs and tissues. Mitotic activity was increased by exposure to 20 mu g/kg TCDD. Thymus size was reduced in fish exposed to the highest doses, but no obvious pathology was found in fish exposed to concentrations as high as 500 mu g/kg. Under laboratory conditions, flounder was not very sensitive to TCDD, but exposure to environmental levels may result in tumor promotion.promoter.
Sub-types of HLA-B27 were detected by cytotoxic T lymphocytes (CTL) generated between HLA-A, -B- and -C-identical B27-positive individuals. We now report the specificity of six independent CTL's ...generated by mixed lymphocyte culture (MLC) of HLA-A, -B and -C serologically identical B27-positive responder and stimulator cells. Three CTL's recognize one sub-type, and three the other. The combined reactivity of all CTL's allows unequivocal "typing" of B27-positive cells for the two different sub-types B27K and B27W. The specificity of two CTL's was analysed by cold-target inhibition. The results indicate that (1) no further sub-types of HLA-B27 can be detected by the CTL's raised in these combinations; (2) the majority of the CTL's is directed against the B27 antigens; and (3) "extra reactions" on B27-negative cells are caused by a subset(s) of CTL's recognizing unknown antigens shared between stimulator and target cells. CTL's raised by stimulation of HLA-B27-negative responder cells with B27-positive cells of either sub-type lysed all B27-positive target cells indiscriminately. In cold-target inhibition, however, B27-positive cells, carrying the sub-type of B27 different from that of the stimulator, could not inhibit the lysis of cells bearing the stimulator sub-type of B27. This indicates the activation, in B27-negative responders, of at least two different groups of CTL clones, one directed against shared determinants of HLA-B27, and one against the HLA-B27 sub-type. Heterogeneity of the HLA-B27 antigen may have implications for studies on the well-known association between this antigen and various diseases.
Interleukin-1beta (IL-1beta) is a central component in innate immunity and the inflammatory response of mammals. Only recently, the first non-mammalian IL-1beta sequences were published. In this ...study, we describe a second IL-1beta sequence (IL-1beta2) in carp with 74% amino acid identity to the carp IL-1beta1 sequence. The existence of two IL-1beta copies in the carp genome probably originates from the tetraploid nature of the species. In contrast to the first carp IL-1beta sequence, IL-1beta2 is represented by multiple genes with 95-99% identity. Detection of several IL-1beta2 sequences within individual homozygous fish suggests the presence of multiple copies of the IL-1beta2 gene in the carp genome, possibly as a result of subsequent gene duplication of IL-1beta2. In vivo, constitutive mRNA expression of both IL-1beta genes was found in healthy carp. IL-1beta2 mRNA expression could be up-regulated in head kidney cells similar to carp IL-1beta1, in vivo by infection with Trypanoplasma borreli and in vitro by stimulation with lipopolysaccharide (LPS). Cortisol, the major glucocorticoid in fish, is an endocrine-derived fator mediating IL-1beta expression. Although constitutive IL-1beta expression was inhibited by a physiological dose of cortisol, cortisol synergistically enhanced LPS-induced IL-1beta expression in carp. Involvement of the transcription factor nuclear factor (NF)-kappaB in expression of IL-1beta1 and IL-1beta2 was demonstrated. Ratio of IL-1beta expression was determined and this showed IL-1beta1 mRNA expression to be at least tenfold higher compared with IL-1beta2. The possibilities of IL-1beta2 being a functional gene or approaching pseudogene status are discussed.
Cytotoxic T lymphocytes were activated in primary one-way mixed lymphocyte cultures of cells matched for serologically defined HLA-A, -B and -C antigens. In 16 out of the 29 combinations mismatched ...for the HLA-D/DR antigens, cell-mediated lympholysis of the stimulator cells occurred. The specificity of 5 selected cytotoxic T lymphocytes was studied in detail. Three of these cytotoxic T lymphocytes recognize antigenic determinants associated with HLA-Bw35 (Breuning et al. 1984, II). The 2 other cytotoxic T lymphocytes failed to lyse T-target cells enriched by rosetting with sheep red blood cells, whereas target cells from the 'non-T' fraction were strongly lysed, indicating that antigenic determinants associated with Class-II HLA molecules were the targets recognized by these cytotoxic T lymphocytes. This notion was supported by a study of a panel of HLA-typed third-party target cells. One cytotoxic T-lymphocyte population preferentially lysed HLA-DR2-positive target cells. Family studies, including a family with a recombination between HLA-B and -D, showed that the target antigen recognized by the latter cytotoxic T lymphocyte segregated with DR2. The second cytotoxic T-lymphocyte population recognized a determinant associated with DRw8. However, in 13 of the 29 HLA-A-, -B- and -C-identical, D/DR-different combinations, cell-mediated lympholysis of stimulator target cells could not be detected, not even on enriched 'non-T' target cells. Thus, after primary mixed lymphocyte culture of HLA-A-, -B- and C-identical, HLA-D/DR-non-identical cells, cytotoxic T lymphocytes directed against sensitizing Class-II molecules can be detected in some combinations, but not in others.
We compared five cytotoxic T lymphocytes raised by primary mixed lymphocyte cultures of HLA-A, -B and -C serologically identical Bw35-positive responder-stimulator combinations. When tested on a ...panel of third-party target cells, the reactivity pattern of these cytotoxic T lymphocytes allowed the distinction of three subtypes of HLA-Bw35. Cold-target inhibition experiments and analysis of CTL activity at the clonal level showed the existence of subsets of CTLs directed against distinct antigenic determinants associated with HLA-Bw35.
