Collagen antibodies in toxic oil disease

Chemical exposure-induced systemic fibrosing disorders: Novel insights into systemic sclerosis etiology and pathogenesis

Numerous drugs and chemical substances are capable of inducing exaggerated tissue fibrotic responses. The vast majority of these agents cause localized fibrotic tissue reactions or fibrosis confined to specific organs. Although much less frequent, chemically-induced systemic fibrotic disorders have been described, sometimes occurring as temporally confined outbreaks. These include the Toxic Oil Syndrome (TOS), the Eosinophilia-Myalgia Syndrome (EMS), and Nephrogenic Systemic Fibrosis (NSF). Although each of these disorders displays some unique characteristics, they all share crucial features with Systemic Sclerosis (SSc), the prototypic idiopathic systemic fibrotic disease, including vasculopathy, chronic inflammatory cell infiltration of affected tissues, and cutaneous and visceral tissue fibrosis. The study of the mechanisms and molecular alterations involved in the development of the chemically-induced systemic fibrotic disorders has provided valuable clues that may allow elucidation of SSc etiology and pathogenesis. Here, we review relevant aspects of the TOS, EMS, and NSF epidemic outbreaks of chemically-induced systemic fibrosing disorders that provide strong support to the hypothesis that SSc is caused by a toxic or biological agent that following its internalization by endothelial cells induces in genetically predisposed individuals a series of molecular alterations that result in the development of SSc clinical and pathological alterations.

Immunotoxic response of oleic acid anilide and its hydrolysis products in female MRL (+/+) mice

An epidemic of a multi-systemic disease, known as the toxic oil syndrome (TOS), was caused by consumption of edible oil denatured with 2% aniline. Oleic acid anilide (OAA) has been suggested as one of the most likely etiologic agents responsible for TOS based upon its presence in high quantities in TOS-related oil samples. The aim of this study was to evaluate the immune response of OAA and contribution of its hydrolysis products (aniline and oleic acid) in the immunotoxic response. Female MRL(+/+) mice were treated with equimolar doses of OAA, aniline or oleic acid (0.8 mmol/kg), i.p., twice a week for 6 weeks. The levels of immunoglobulins IgE, IgG and its isotypes (IgG(1), IgG(2a), IgG(2 b), and IgG(3)), and the appearance of antinuclear antibodies (ANA) were determined in the serum. Exposure to OAA and oleic acid caused significant increases in IgG, IgG(1), IgG(2a), and IgG(2b) levels as compared to aniline and control groups, whereas IgG(3) value increased only in OAA-treated mice. The IgE levels in OAA-, aniline-, and oleic acid-treated groups were higher than the controls. Among the various treatment groups, sera from 50% of the OAA-treated mice gave rise to intense homogenous fluorescence patterns on Hep-2 cells, suggesting the presence of significant levels of antinuclear antibodies (ANA). Furthermore, analysis of serum cytokines showed significant increases in G-CSF levels in OAA- and aniline-treated mice. Among the tissues examined, morphological changes were confined to the spleen, which showed increased lymphocyte population in OAA- and aniline-treated mice. These studies indicate that OAA and its hydrolysis products cause perturbations in the immune response, and could contribute to TOS-related immune derangements.

Investigating the onset of autoimmunity in A.SW mice following treatment with 'toxic oils'

In 1981, over 20,000 people were struck with toxic oil syndrome (TOS). H-2s strains of mice have been shown to develop symptoms of TOS after exposure to toxic oil. We examined the effects of toxic oil on A.SW mice, which are susceptible to chemically-induced autoimmunity, but do not spontaneously develop autoimmune disease. Mice were treated with three types of toxic oil: CO756 (case oil from Spain), RSD99 (rapeseed oil with no 3-(N-phenylamino)-1-2-propanediol (PAP) derivatives) and RSA99 (rapeseed oil supplemented with PAP derivatives). Mercuric chloride treated mice were used as a positive control. After toxic oil treatment, there were no consistent differences in body weight or organ weight (liver, kidney, thymus and spleen) as a percent of body weight at any of these timepoints: 2.5, 5 or 10 weeks. We also found that treatment with toxic oil did not induce autoantibody formation or lead to increased serum levels of IgG1, IgG2a or IgE at these timepoints. Conversely, at all timepoints, there were significant increases in organ weight as a percent of body weight in the mercury treated mice. Additionally, mercuric chloride treated mice had elevated serum levels of IgG1, IgG2a and IgE and developed anti-nuclear and anti-collagen antibodies.

Immunoglobulin and autoantibody responses in MRL/lpr mice treated with 'toxic oils'

The toxic oil syndrome (TOS) occurred in Spain in 1981 as a result of ingestion of oil mixtures containing aniline-denatured rapeseed oil. The disease afflicted almost 20000 people, resulted in more than 400 deaths, and mimicked an autoimmune disease in all patients. Phenilamine-propanediol (PAP) has been implicated as a possible etiologic agent of TOS but absence of an acceptable animal model to evaluate the autoimmune potential of the 'case oil' has hindered identification of the actual etiologic agent(s). The purpose of this study was twofold; (1) to develop an animal model of human disease to investigate the immunological etiology and pathogenesis of TOS and (2) to determine if the 'case oil' responsible for TOS and/or two synthesized oils either induced or exacerbated the systemic autoimmune disease that occurs spontaneously in the MRL/lpr mouse. The oils tested were a denatured rapeseed oil collected from a family (case oil) who were affected by the TOS (CO756), a rapeseed oil denatured with 2% aniline and enriched with a mixture of diesters of PAP (RSD), and a rapeseed oil denatured with 2% aniline but contained no diesters of PAP (RSA). Female MRL/lpr mice, 7 weeks of age, received orally either an undiluted (neat) or a 1:10 diluted dose of each test oil, canola oil (oil control), water (nai;ve control), or 50-ppm mercury (positive control). Half of each group was sacrificed after 5 weeks of exposure and the remaining mice after 10 weeks of exposure. Serum IgG1, IgG2a, IgE isotypes and antinuclear (ANA), collagen type II, histone, single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and Sm autoantibody concentrations were determined after 5 and 10 weeks of exposure. The oils did not significantly affect the concentrations of the serum immunoglobulins, although a shift in the IgG1:IgG2a ratio towards IgG1 was noted from 12 to 17 weeks of age (5-10 weeks of treatment). The oils did however stimulate the systemic autoimmune response. The RSD neat treatment resulted in a nonsignificant but noted increase in autoantibodies to collagen (10 weeks), histone (10 weeks) and dsDNA (5 and 10 weeks). CO756 neat increased the serum levels of ANA (5 weeks), collagen (5 weeks) and dsDNA (5 and 10 weeks). The RSA 1:10 dilution increased ssDNA and dsDNA autoantibodies at 5 weeks. The results suggest that PAP is an active principle of these noted responses. These data, coupled with the toxicology and pathology data from this study (Toxicol. Path. 29 (2001) 630), revealed that the three oils incited induction of the lymphoproliferative syndrome and that the two oils containing PAP induced and enhanced the systemic autoimmune response that develops spontaneously at an early age in the MRL/lpr mouse. There was also a positive correlation noted between serum autoantibody concentrations and progression of the idiopathic autoimmune syndrome in the MRL/lpr mouse.

Strain-dependent cytokine profile and susceptibility to oleic acid anilide in a murine model of the toxic oil syndrome

The toxic oil syndrome (TOS) was caused by the ingestion of an adulterated rapeseed oil containing oleic acid anilide (OAA). It was characterized by lethal symptoms in the acute phase and by symptoms of idiopathic autoimmune diseases in the chronic phase. The pathogenetic mechanisms remain unclear. In a murine model of TOS we demonstrate strain-dependent effects on the immune system after treatment with OAA intraperitoneally. While C57BL/6 (H-2b) mice develop a polyclonal B cell activation without disease symptoms, most A/J (H-2a) mice suffer an acute lethal wasting disease. These differences are reflected in the splenic cytokine gene expression and secretion and in the Ig production. Increased IgE serum levels and reduced TNF-beta mRNA suggest a Th2 cell response in C57BL/6 mice. In A/J mice, splenocytes express IL-1alpha, IL-10, and IFN-gamma mRNA in vivo and secrete high levels of TNF-alpha in vitro. These observations resemble the human condition in TOS with development of either an acute lethal disease or a chronic autoimmune-like disease. As in other chemical-induced reactions genetic susceptibility seems to be important.

The toxic oil syndrome: an example of an exogenously induced autoimmune reaction. Toxic oil syndrome

The toxic oil syndrome (TOS) is a chemically induced autoimmune-like reaction in humans. The etiologic agent(s) have so far not clearly been identified. A short overview is given on this disease which is associated with a unique antibody specificity to cryptic epitopes of C-reactive protein in affected patients. In addition a murine model for TOS is described which suggests that genetic susceptibility might play a role in inducing a similar syndrome in mice. These differences are reflected in the immunological alterations and cytokine production caused by the toxicant.

Immunological basis of toxic oil syndrome (TOS)

The toxic oil syndrome (TOS), a multisystemic disease, that occurred in Spain in 1981, was caused by the ingestion of rapeseed oil denatured with 2% aniline. Due to the clinical course of the disease, immunopathological mechanisms have been suspected but a direct connection was never demonstrated. To analyse this possibility, we determined several immunological parameters in the sera of patients with TOS and without the disease, using a case-control design: total immunoglobulins, IgG and IgE antibodies against different toxic agents (oleylanilide, aniline, linoleyl-anilide, and 3-phenylaminopropane-1-2-diol), autoantibodies, cytokines (IL-4, IL-6, TNF, GM-CSF) and soluble receptors (sCD23 and sIL-2R). We detected high levels of sIL-2R in TOS patients compared to controls (P < 0.0001). A higher levels of sCD23 and IgE were also found. In addition, the response to oleyl-anilide of peripheral blood lymphocytes from TOS patients was studied and a significant proliferative response in 30% of TOS patients versus 5% controls was observed. Our data support the implication of the immune system in the acute phase of TOS, with a possible activation of T-cells and release of cytokines, that could explain some of the clinical findings in this phase of the disease.

Expression of types I, III and IV collagen genes in fibrotic skin and nerve lesions of toxic oil syndrome patients

We have studied the skin and nerve fibrosis in toxic oil syndrome by in situ hybridization using specific cDNA probes for types I, III, and IV collagens. Fibroblasts with high levels of type I and III collagen mRNA were observed in biopsies from fibrotic skin areas. Similarly, type IV collagen mRNA was abundant in cells within the fibrotic process of the nerves. These results suggest that the excessive accumulation of collagen in toxic oil syndrome results from transcriptional activation of collagen genes in a subpopulation of fibroblasts.

Persistence of respiratory abnormalities four years after the onset of toxic oil syndrome

We studied a random sample of 436 subjects with TOS aged 18 to 60 years, to assess the prevalence of respiratory involvement four years after onset of the syndrome. Clinical evaluation together with chest roentgenograms, electrocardiogram and functional respiratory tests were carried out. Respiratory involvement occurred in 390 (89.4 percent) individuals and was the most common abnormality detected, followed by neurological disorders in 289 (66.3 percent), osteoarticular symptoms in 171 (39.2 percent), psychiatric disorders in 96 (22 percent), hepatic involvement in 91 (20.9 percent), and sclerodermatous sequelae in 89 (20.4 percent). Among patients with respiratory involvement, dyspnea and cough were the most common complaints. Decreased VC was observed in 151 (34.6 percent) patients and reduced transfer factor of CO in 95 (21.8 percent) patients. Airway obstruction and alveolar hypoventilation were observed only in nine (2.1 percent) patients. Six (1.4 percent) patients suffered from pulmonary artery hypertension.