[Two cases of hot tub lung disease: Environmental investigations]. / Deux cas de pneumopathie d'hypersensibilité du jacuzzi : enquête environnementale.

INTRODUCTION: Hot tub lung is a hypersensitivity pneumonitis (HP) due to exposure to inhaled non-tuberculous mycobacteria, the most frequent being Mycobacterium avium complex (MAC). CASE REPORT: A French couple developed typicalHP in the context of a repeated use of hot tubs. The husband had a severe hypoxemic form whereas his wife had a micronodular form with patchy ground glass on the thoracic scan, with less severe functional impairment. MAC was recovered in the hot tub water, but not in broncho-alveolar lavage fluid, and serologies were negative. Samples taken at home showed unusual exposure to Aureobasidium pullulans and Aspergillus flavus, as well as the presence of potentially responsible domestic molds. Blood precipitins for these microorganisms were identified. The evolution was favorable after removal of the hot tub. CONCLUSIONS: These cases represent two of the typical presentations of hot tub lung, with a possible HP to an antigen other than MAC, which may have been enhanced by chronic exposure to multiple microorganisms.

Characterization of arterial antigens using arterial antigen-reactive T cell clones from spontaneously hypertensive rats.

We have previously demonstrated that arterial antigens derived from the aorta of spontaneously hypertensive rats (SHRs) stimulate arterial antigen-reactive T cell clones established from the spleens of SHR to proliferate and release cytokines. To identify immunogenic protein components associated with the arterial wall, arterial antigen-reactive T cell clones were tested against arterial antigens separated by SDS-PAGE and transferred to nitrocellulose. The greatest T cell reactivity was obtained with protein bands of molecular weight 66 kDa, 50 kDa, and 45 kDa. T cell clones reactive against the 50 and 45 kDa antigens from gels failed to respond to proteins of other molecular weight (M(r)) separated under reducing or nonreducing conditions, suggesting that these molecules are not subunits of larger proteins and may represent monomeric antigens polymerized into the arterial wall. These data suggest that certain epitopes of arterial wall antigens are immunogenic. T cells activated with these immunogenic epitopes could initiate or perpetuate vasculitis in the arteries of hypertensive rats.

Isolation and functional characterization of IL-2 responsive T cell clones from NZB x NZW F1 mice.

Autoantigen-reactive T cells might play an important role in the pathogenesis of systemic lupus erythematosus (SLE). Autoantigen-reactive T cell clones were generated from spleens of NZB x NZW F1 (BWF1) and normal control BALB/c mice with interleukin-2 (IL-2), a procedure that selects for in vivo activated antigen-reactive T cells. The antigen-specificity of the T cell clones was tested by using a panel of candidate autoantigens. The T cell clones from BWF1 mice but not those from BALB/c mice proliferated against heparan sulfate, the major glycosaminoglycan of glomerular basement membrane. None of the clones proliferated against dsDNA or cardiolipin. All the heparan sulfate-reactive T cell clones had the ability to selectively augment the production of IgG anti-dsDNA autoantibodies. When cultured with either heparan sulfate or Concanavalin A, the T cell clones produced high levels of IL-4 and IL-5 with no detectable IL-2 or IFN-gamma. In contrast, T cell clones derived from BALB/c mice augmented the production of total polyclonal IgG but not the production of anti-dsDNA antibodies. These studies indicate the existence of heparan sulfate-reactive T cells in BWF1 mice. Characterization of heparan sulfate-reactive T cells that could selectively augment anti-dsDNA production will permit the design of targeted and antigen-specific therapy.

Neutrophil-mediated damage to vascular endothelium in the spontaneously hypertensive rat.

Lysis of aortic endothelial cells (EC) by neutrophils from spontaneously hypertensive rats (SHR) was investigated using a nonradioactive cytotoxicity assay. Interleukin-1-activated EC, but not unstimulated EC, were effective target cells for lysis by SHR neutrophils. Supernatants from activated neutrophil did not exert a cytotoxic effect on EC. Inhibitors of reactive oxygen species did not affect the cytotoxicity of neutrophils on EC. In contrast, inhibitors of serine protease and elastase markedly inhibited the cytotoxicity of neutrophils on EC. Antibodies against the endothelial cell surface ligands ICAM-1 (CD54) and E-selectin (CD62E) inhibited the adhesion and cytotoxicity of activated neutrophils on EC. The cytotoxicity of neutrophils required direct cell-to-cell contact because separating them with a microporous membrane abrogated the neutrophil-mediated cytotoxic activity. These results demonstrate that SHR neutrophils possess potent cytotoxicity against cytokine-activated EC. Neutrophil-mediated damage of EC could contribute to organ damage in hypertension under conditions of local or systemic activation of neutrophils.

Accumulation of malondialdehyde in mouse heart following acute dosing with adriamycin is strain specific and unaffected by cardiac catalase status.

CDF1 and C57BL/6J male mice were acutely dosed with Adriamycin (ADR), and total cardiac malondialdehyde (MDA) quantitated following isolation by modification of previously developed procedures. Cardiac MDA content in CDF1 mice increased significantly 5 days following ADR dosing as reported by others, but was unchanged in C57BL/6J mice. ADR-induced mortality and a significant loss in cardiac weight 2-3 days after treatment was similar in both strains. Cardiac lipid hydroperoxide (LH) content was also unchanged in C57BL/6J mice dosed acutely with ADR. However, hepatic LH content increased rapidly following treatment with ADR, reaching maximal level 1 day following treatment before returning to below untreated levels 24 hours later. Studies with genetically acatalasemic C57BL/6J mice showed that neither cardiac nor hepatic lipid hydroperoxide content in ADR-dosed animals is affected by tissue catalase levels. These results demonstrate that C57BL/6J mouse heart is refractory to ADR-induced lipid peroxidation (LP) although overall mortality from the drug is unaffected, and do not support the hypothesis that ADR-induced mortality in mice is a consequence of cardiac LP.

Induction of systemic lupus erythematosus-like disease in mice by immunization with heparan sulfate.

Experimental systemic lupus erythematosus (SLE)-like disease was induced in BALB/c mice by immunization with heparan sulfate, the major glycosaminoglycan of glomerular basement membrane. Following booster injections with heparan sulfate (HS), high levels of anti-HS, anti-dsDNA, and anti-cardiolipin antibodies were detected in the sera of the immunized mice. An enzyme-linked immunospot (ELISPOT) assay indicted that IgG anti-HS and anti-dsDNA antibody-secreting cells were present in the kidneys and most likely contributed to antibody localization. Antibodies eluted from the kidneys of immunized mice were found to react strongly with HS and dsDNA when tested in vitro. The HS-immunized mice developed moderate to severe levels of proteinuria. Histologic examination of kidneys from HS-immunized mice revealed deposition of immunoglobulin in the kidneys. Our results describe the induction of SLE-like disease in normal mice following immunization with HS. This experimental model may be useful for understanding the immunologic basis for autoimmunity to HS.

Suppression of systemic lupus erythematosus disease in mice by oral administration of kidney extract.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the increased production of antibodies reactive with a variety of self and non-self antigens. A number of immunomodulatory therapies have been investigated for the disease process. Intragastric administration of low dose kidney extract (KE) three times weekly for 5 weeks and then weekly until 6 months of age in SLE mice, showed decreased anti-dsDNA antibody levels, less kidney damage and significantly prolonged survival compared with control phosphate buffered saline (PBS)-fed mice. The KE-fed mice also exhibited reduced T cell proliferative response to KE in comparison with PBS-fed controls. Serum isotype distribution of the anti-dsDNA antibodies revealed a marked reduction of IgG1 and IgG3 responses in the KE-fed mice. While the renal inflammatory cell infiltration and expression of interleukin-4 (IL-4) and IL-10 were markedly suppressed, no local enhancement of transforming growth factor-beta (TGF-beta) was detected. Oral administration of low dose KE, however, upregulated expression of IL-2, IFN-gamma and TNF-alpha in the kidneys and suppressed glomerulonephritis. These findings suggest that oral KE affects the disease process in SLE and raise the possibility that oral administration of KE or other potential autoantigens may provide a new approach for the treatment of SLE.

Autoantibodies against arterial antigens: characterization by ELISA and immunoblot analysis in the spontaneously hypertensive rat.

The presence of autoantibodies directed against arterial antigens in serum samples from spontaneously hypertensive rats and related controls that included Wistar-Kyoto and Sprague-dawley rats were assayed by enzyme-linked immunosorbent assay and immunoblotting technique. Circulating immunoglobulin G antibodies reactive against arterial antigen, as measured by enzyme-linked immunosorbent assay, could be detected in serum samples of 26 of 30 spontaneously hypertensive rats (87%) and 8 of 30 (27%) Wistar kyoto rats. These antibodies (Abs) were not detectable either by enzyme-linked immunosorbent assay or immunoblotting in sera from Sprague-dawley rats. The arterial antigen-reactive antibody was antigen specific, because the binding reactivity was absorbed by arterial antigen but not by fibroblasts or peripheral blood mononuclear cells. Immunoglobulin G arterial antigen-reactive antibody was significantly higher in adult spontaneously hypertensive rats with established hypertension, compared with young prehypertensive rats or normotensive wistar kyoto rats. Immunoblotting of spontaneously hypertensive rats sera revealed reactivity of arterial antigen-reactive antibody against arterial antigen ranging in size from 20 to 97 kDa. Sera from Wistar kyoto rats recognized arterial antigen ranging in size from 40 to 90 kDa. A significant correlation (p < 0.004) was found between adult spontaneously hypertensive rats with established hypertension and the presence of arterial antigen-reactive antibody reactivity against arterial antigen of 20, 69 and 97 kDa. Antibody directed against a 20 kDa arterial antigen was detected in both young prehypertensive rats and adult rats with established hypertension but not in Wistar kyoto or Sprague-dawley rats. Antibodies directed against both 69 and 97 kDa arterial antigens were detected only in spontaneously hypertensive rats sera. These data show that the pattern of arterial antigen-reactive antibody reactivity in sera of hypertensive rats in heterogeneous, and suggest that arterial antigen-reactive antibody directed against few arterial antigens may be involved in the pathogenesis of hypertension in the spontaneously hypertensive rat.

Benzo(a)pyrene enhances atherosclerosis in White Carneau and Show Racer pigeons.

Benzo(a)pyrene (BaP), a major environmental pollutant and component of cigarette smoke, is both carcinogenic and atherogenic in experimental models. We investigated the effect of long-term administration of BaP on atherogenesis in both atherosclerosis-susceptible White Carneau (WC) and atherosclerosis-resistant Show Racer (SR) pigeons. The number and size of arterial lesions in the brachiocephalic arteries in WC and SR females but not males were significantly enhanced after long-term dosing with BaP. Metabolic activation appears to be required for BaP atherogenicity, since benzo(e)pyrene (BeP), a noncarcinogenic analogue of BaP, did not enhance lesion development. Studies with 3H-BaP revealed no significant differences between male and female or between WC and SR pigeons in the arterial distribution of BaP and/or its metabolites. There were no consistent differences in blood pressure or plasma cholesterol levels between breeds or sexes. However, chronic administration of BaP did result in complete infertility in female birds, concomitant with grossly visible changes in ovarian appearance. These results clearly show that long-term dosing with BaP alters ovarian structure and function in treated birds, at the same time aggravating the development of arterial lesions. Thus, BaP-induced atherogenicity in female pigeons may be a consequence of an alteration in estrogen production or of antiestrogenic properties of BaP at the level of the arterial wall and may serve as a highly useful animal model to examine the well-known rapid development of atherosclerosis in postmenopausal women.