IL-1 is required for allergen-specific Th2 cell activation and the development of airway hypersensitivity response

IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR.     

Immunohistochemical study on tissue transglutaminase and copper-zinc superoxide dismutase in human myocardium: Its relevance to apoptosis detected by the nick end labelling method

The influence of free radicals on apoptosis was studied in the human heart; 45 autopsy cases were examined by the nick end labelling method (NELM) that detects DNA fragmentation. Immunostaining for copper-zinc superoxide dismutase (CuZn-SOD) and tissue transglutaminase (tTG) induced frequently during apoptosis were also studied. Positive immunoreaction for tTG was detected in mucinous degeneration of myocardial cells; these same cells were also positive for CuZn-SOD but negative for NELM. Myocardial cells showing basophilic alterations after haematoxylin and eosin staining were also positive for CuZn-SOD but negative for the other markers examined. Positive nuclear reaction by NELM was only observed in myocardial cells showing contraction band necrosis or irregularly shaped nuclei surrounding recent or long-standing infarcted foci. In these the other two markers were negative. Since mucinous degeneration lacks the distinguishing morphological features of apoptosis, immunoreactive tTG in this lesion may not imply that the cells are undergoing apoptosis. tTG can be induced in non-apoptotic conditions and may not be involved in apoptosis induced by infarction. Histological disassociation between CuZn-SOD expression and apoptosis suggests the possibility of a cytoprotective role played by endogenous CuZn-SOD against free radical generation in the human heart.     

Endocytosis of human thyroglobulin (TG) in adenomatous goiter studied by an immuno-electron microscopic procedure

Five cases of adenomatous goiter have been studied by an electron microscope using an immuno-reaction for thyroglobulin (TG) and focusing on the mechanism of endocytosis. Positive stain for TG was demonstrated in follicular lumina, large reabsorbed colloid droplets and small subapical vesicles. Endocytotic vesicles ranging from 320 nm to 1600 nm in diameter were observed in the cytoplasm as pits in the apical plasma membrane. Some of them showed direct connection with the positive stain for TG in the follicular lumen and the others were completely ingested in the cytoplasm. With statistic analysis, a majority of the vesicles showing the positive stain for TG in the cytoplasm distributed in the range of 200 nm to 1200 nm in diameter with the peak in 300 nm to 399 nm and was situated within an extent of the diameter measured from the endocytotic vesicles. Engulfment of colloid by pseudopods and fusion of the reabsorbed colloid droplets were encountered as extremely rare findings and appeared to play no major role for formation of large colloid droplets in adenomatous goiter.     

Telomerase activity in the human endometrium throughout the menstrual cycle

In a total of 41 endometrial tissue samples, the relationship between telomerase activity and proliferating cell nuclear antigen (PCNA) labelling index was studied. In samples of endometrium from the proliferative phase of the menstrual cycle, telomerase activity was found in 15 out of 17 cases (88%). Two samples from the early proliferative phase showed negative telomerase activity and a low PCNA labelling index. However, three out of 16 samples of early secretory phase endometrium showed telomerase activity and a PCNA labelling index. In mid- to late secretory phase endometrium, in menopausal endometrium and in decidualized endometrium induced by progesterone neither telomerase activity nor PCNA labelling was found. These results suggest that telomerase activity of the endometrium may be correlated with the proliferative potential of the epithelial cells and that its activity may be regulated by oestrogen.      

Further development of a recombinant feline herpesvirus type 1 expressing the Gag protein of feline immunodeficiency virus

Summary.  We have previously reported the construction of a recombinant feline herpesvirus type 1 (FHV-1), designated C7301ddlTK-gag, expressing the Gag precursor protein of feline immunodeficiency virus (FIV). In this study, we report the construction of a further recombinant FHV-1 (ddlTK(gBp)-gag) which carries an FHV-1 gB promoter sequence upstream of the FIV gag gene of C7301ddlTK-gag. Strong expression of the FIV Gag protein by ddlTK(gBp)-gag was confirmed by immunoblot analyses and enzyme-linked immunosorbent assays. Although C7301ddlTK-gag and ddlTK(gBp)-gag failed to induce anti-FIV Gag antibodies in cats, we confirmed the infectivity and stability of these recombinants in cats. Received January 14, 2000 Accepted August 4, 2000