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E Martín-Orozco

Publications and source records attributed to E Martín-Orozco.

5 recordsLinked to original sources

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.

Anilides↗

Ole e I: epitope mapping, cross-reactivity with other Oleaceae pollens and ultrastructural localization.

Ole e I is the major allergen derived from olive tree pollen (Olea europaea) and it is composed of two polypeptides with molecular weights (MWs) of 18 and 20 kD. A panel of six monoclonal antibodies (mAbs) has been prepared and used to map antigenic determinants on this molecule. Four epitope determinants have been identified on Ole e I. Using the purified mAbs produced against Ole e I, we have analyzed the common epitope determinants in olive (O. europaea) and different Oleaceae pollens: ash (Fraxinus excelsior); privet (Ligustrum vulgare); lilac (Syringa vulgaris), and forsythia (Forsythia suspensa). ELISA showed three reactivity groups depending on the recognition of monoclonal antibodies: (1) olive and ash; (2) olive, ash, privet and lilac; and (3) olive, ash, privet, lilac and forsythia. Immunoblotting studies on Oleaceae pollen extracts with these mAbs showed a very similar cross-reactivity pattern. The 18- and 20-kD MW proteins were present in each pollen, except in the case of forsythia. In this case the reactivity pattern was associated with 50- to 55-kD protein bands. This band was recognized by a pool of sera from olive-allergic patients. Finally, ultrastructural localization of Ole e I antigen was performed on the mature olive pollen grain. Ole e I was located in association with dilated endoplasmic reticulum cisternae. Pollen grain walls, nuclei and cytoplasmic organelles were totally devoid of the allergen.

Allergens↗

Modulation of the Fc gamma RII and Fc gamma RIII induced by GM-CSF, IFN-gamma and IL-4 on murine eosinophils.

Murine eosinophils express the low-affinity Fc gamma receptors recognized by the monoclonal antibody (mAb) 2.4G2, which are involved in the activation of these cells. We have studied the membrane and RNA expression of the low-affinity Fc gamma receptors on murine eosinophils stimulated by granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon-gamma (IFN-gamma), and interleukin-4 (IL-4). Flow cytometric analysis (FACS) of eosinophils incubated with GM-CSF and IFN-gamma showed an up-regulation on the expression of these receptors with a maximal effect at 24 hr. IL-4 failed to induce any positive or negative effect in these cells. To assess the pattern of expression of the low-affinity Fc gamma receptors on eosinophils, Northern blot analyses were carried out using specific cDNA probes encoding for the Fc gamma RII and Fc gamma RIII. Murine eosinophils constitutively express transcripts for Fc gamma RII and RIII. Incubation with GM-CSF from 3 to 12 hr produced a potent induction of the two transcripts studied (Fc gamma RII and RIII). IFN-gamma did not induce any important up-regulation of the two transcripts from 3 to 12 hr of incubation. By contrast, IL-4 produced a marked inhibition of both transcripts at 24 hr of incubation. Expression of the gamma-chain transcript which is associated with Fc gamma RIII has been detected on freshly isolated eosinophils. This study demonstrates a different regulation pattern of these receptors depending on the cytokine or growth factor used to stimulate murine eosinophils.

Animals↗

Isolation of three allergenic fractions of the major allergen from Olea europea pollen and N-terminal amino acid sequence.

A method to isolate the major allergen from olive pollen (Ole e I) in high yield is described. The allergenic fraction has been separated into 3 subfractions by reverse-phase HPLC. All these fractions were reactive to allergic sera from olive-sensitized patients, giving similar responses. No significant differences were observed between the amino acid compositions of these three proteins. The amino acid sequence of the first 27 amino acid residues from the N-terminal end is given. No homologies have been detected between Ole e I and other known allergens obtained from pollen.

Allergens↗