Because of the timing of serum EMA and NFR antibodies, circulating ANA were evaluated at three time-points: during EMA-positive results, under EMA disappearance/NFR-positive results and after NFR disappearance. At all time-points, serum ANA were positive in two of 20 CD see more patients in group 1. In both cases, an ANA-S antibody pattern (subpattern: fine speckled) was visible. None of the 15 subjects in group

3 presented serum EMA-positive results, while two showed an NFR-like pattern on monkey oesophagus sections. The latter two subjects were put on a GFD for 12 months. Serum EMA and NFR antibodies were evaluated each month, showing no changes in the NFR-like pattern. The characterization of this NFR-like pattern showed that it belonged simultaneously to IgA1 and IgA2 subclasses, and that it was localized in the nucleus. The results of the present study demonstrate that serum IgA from CD patients are able to react with two nuclear antigens determining the appearance of a nuclear fluorescence selleck inhibitor reactivity (NFR) antibody pattern on monkey oesophagus sections used routinely for EMA detection. Moreover, as NFR antibodies are detectable

in serum as long as the CD patients consume gluten and disappear after gluten withdrawal from the diet, they are gluten-dependent and related strictly to CD. The autoimmune nature of CD is understood clearly [5–7], and the main autoantigen is well known to be tTG [11]. However, tTG is not the only CD-related autoantigen, as other tissue components have been shown to be a target of coeliac autoimmunity [12–15]. In serum of active CD patients, antibodies against thyroid and pancreas structures, cytoskeleton molecules and central nervous

Dimethyl sulfoxide system-related antigens have been found previously [14]. The present study adds a new antigen type to the list, as we found that serum IgA from untreated CD patients react with two NFR-related nuclear antigens of 65 and 49 kDa. The identity of NFR-related autoantigens is as yet unknown, but based on the different distribution of EMA and NFR reaction sites on monkey oesophagus sections it is reasonable to hypothesize that these reactivities are due to distinct antigenic specificity. Indeed, EMA and NFR antibody patterns are never observable simultaneously during total IgA EMA detection but, using secondary mAbs against IgA subclasses (IgA1 and IgA2) coupled with different fluorochromes (FITC and TRITC), the presence of two different and not overlapping fluorescence signals becomes evident. That the main endomysial antigen, known to be tTG [11], has a different molecular weight with respect to the newly identified autoantigens (85 versus 65 and 49 kDa), further confirms the hypothesis that EMA and NFR are two distinct antibodies.