After the immunizing infection, the key experimental immunized-ch

After the immunizing infection, the key experimental immunized-challenged group was rested for 4 weeks to enable the mucosa to recover, before being challenged with a low-dose secondary infection. Our hypothesis is that challenged animals should respond with a considerably more vigorous intestinal inflammatory response than that evident during primary exposure, and to enable this

to be quantified accurately against baseline values of each of the parameters that we measured, we included four carefully chosen control groups. The strain of A. ceylanicum used was that maintained at the University of Nottingham since 1984, originally acquired from Dr. Rajasekariah of Hindustan CIBA-Geigy Ltd., Bombay, India. It is believed to be of dog origin. The methods employed for maintenance of the parasite, for worm recovery and faecal egg counts have all been described previously in full (16,19). Worms were Dabrafenib chemical structure removed from infected animals by treatment with ivermectin (‘Ivomec super’ MSD AGVET, Division of Merk Sharp and Dohme Limited, Holland). A stock concentration of 200 μg/mL drug was made by a 1 in 50 dilution using distilled water and this was used to treat at 200 μg/kg body weight. The Golden hamsters (DSN strain) used in this study were originally obtained from Harlan Olac in 1983 and since then maintained

in the animal house of the School of Biology as a closed colony. Only female hamsters were used

in this experiment. Animals were kept under conventional animal house conditions. Pelleted food and tap water were supplied learn more ad libitum. Cages were cleaned twice a week to prevent re-infection. Animals were first weighed 1 or 2 weeks before infection and thereafter twice a week until the completion of each experiment. As the colony was maintained under conventional animal house conditions, the animals were exposed to various micro-organisms present in the environment. To prepare hamsters for infection and reduce other competing intestinal micro-organisms, all animals were pre-treated for 1 week with Emtryl (May & Baker, Dimetridazole at a concentration of 1 g/L in drinking water), then for another week with Terramycin (Pfizer, oxytetracycline hydrochloride, 3 g/L in drinking Carbohydrate water) and were returned to normal drinking water for 1 week prior to infection. Animals were used at approximately 8–12 weeks of age. The methods used to measure the height of villi, the depth of the Crypts of Lieberkühn and mitotic activity were described comprehensively by Alkazmi et al. (20). Methods for assessing the mast cell, goblet cell, eosinophil and Paneth cell responses were reported earlier in full (18). In all the histological observations reported here, we counted cells/mm2 of mucosal tissue on appropriately stained sections, using the Weible 2 graticule as described by Kermanizadeh et al. (29).

First, unlike mHFE+ skin grafts

onto DBA/2 mHfe KO mice (

First, unlike mHFE+ skin grafts

onto DBA/2 mHfe KO mice (whether TCR-transgenic or not), with local and coinciding antigenic charge and inflammatory reaction, the anti-mHFE TCR-transgenic CD8+ T cells were i.v. injected into Rag 2 KO DBA/2 mHFE+ mice in a noninflammatory context (LPS was administered on day 12, at which time the CFSE experiment established that the injected cells had already disappeared). Second, albeit HFE is broadly expressed, its expression in antigen-presenting cells in particular dendritic cells is relatively limited [[4]] and HFE is expressed in a variety of nonantigen-presenting cells including cells of the liver, an organ endowed with strong tolerogenic properties [[35]]. It should however be stressed that the absence of GVHD

when HFE is the sole molecule targeted by a monoclonal CD8+ T-cell population does not exclude that in other situations (additional minor histocompatibility mismatches, polyclonality of the injected cells, etc.) an HFE mismatch would not contribute to GVH reactions, as documented for HY mismatches in human clinic [[36]]. Whereas most anti-mHFE TCR-transgenic T lymphocytes are blocked in the thymus at the CD4+ CD8+ double positive stage in DBA/2 mHFE+ mice, some cells escape deletion and are found in the periphery. These cells express a low level of the transgenic TCR, are CD4−, CD8−, CD25− and approximately 50% of them express NK-cell markers, NKp46, and DX5. These cells differ from Treg cells phenotypically (CD4−, FoxP3−) and functionally (no suppressive activity) but share similarities (co-expression of NK-cell markers, reduced amounts of TCR) with conventional NKT cells [[37]]. However, Selleckchem BMS-777607 unlike NKT cells, they do not express the PLZF transcription factor [[38]] and produce neither IL-4, nor IFN-γ but produce IL-6, IL-10, and hepcidin. They must therefore have been differently reprogrammed. Whether these cells are a residual and not a functional population of lymphocytes simply “parked” in the periphery or, as their production of IL-6 and hepcidin (two key regulators of iron metabolism) may suggest, contribute to iron homeostasis is an open question. From that point of view it has to be stressed that similar cytokine productions

were not observed with H-2 Db-restricted anti-HY TCR transgenic T lymphocytes from male mice that similarly downregulate their TCRs O-methylated flavonoid [[34]]. Several other observations support the notion that the immune system plays a regulatory role in iron metabolism. Iron overload in Rag/β2m double KO is more accentuated than in β2m single KO mice [[39]] and, in hemochromatosis patients, an inverse correlation has been observed between CD8+ T-cell numbers and disease severity [[40]], a possible consequence of the recently documented production of hepcidin by T lymphocytes [[41]]. Having established that mHFE is an autonomous histocompatibility antigen for mHfe KO and mHfe-C282Y mutated mice, it remains to be seen whether the same is true for hereditary hemochromatosis patients.

enterica serovar Typhimurium expressing swIL-18 and swIFN-α showe

enterica serovar Typhimurium expressing swIL-18 and swIFN-α showed the lowest severity of clinical signs. In particular, LEE011 ic50 the clinical score of piglets co-administered Salmonella vaccine expressing swIL-18 and swIFN-α was lower than that of piglets administered Salmonella vaccine expressing either swIL-18 or swIFN-α, with apparent differences at seven days post-challenge

(Table 1). Cumulative daily weight gain was measured to more precisely quantify the alleviation of clinical signs. Consistently, piglets co-administered S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α displayed a significantly increased weight gain, compared to groups that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α (Fig. 4a). However, when changes in body temperature of PrV-infected piglets were monitored, there were no significant differences between the group co-administered with S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α, and the PFT�� datasheet group that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α (Fig. 4b). Taken together, these results indicate that co-administration

of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α results in the enhanced alleviation of clinical severity caused by PrV infection, compared to individual administration of S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α. To evaluate the effect of orally co-administered S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α on virus shedding from PrV-infected piglets, the amount of PrV in nasal swabs was determined Masitinib (AB1010) daily in all groups by the use of a

conventional plaque assay from 3 to 14 days post-challenge. PrV shedding was detected from 3 days after PrV infection and peaked at 6 days (Fig. 5). Piglets that received S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α had lower peak levels of PrV shedding at 6 days post-inoculation, when compared to piglets that received no treatment and S. enterica serovar Typhimurium harboring pYA3560. Furthermore, piglets orally co-administered with S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α showed significantly reduced PrV shedding at 6 days post-challenge compared to those administered S. enterica serovar Typhimurium expressing either swIL-18 or swIFN-α. In addition, the co-administration of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α provided a shortened duration of virus shedding. These results indicate that co-administration of S. enterica serovar Typhimurium expressing swIL-18 and swIFN-α produced enhanced inhibition of virus shedding from PrV-infected piglets. The present study demonstrates that the co-administration of S.

This may delay the development of protective immunity and consequ

This may delay the development of protective immunity and consequently lead to reinfection with low number of parasites. This study

was supported by grants from Fundação de Amparo à Pesquisa do Estado de JQ1 chemical structure Minas Gerais (FAPEMIG) and CNPq. Acknowledgement is also due to Juliana Froeseler, Remo de Castro Russo, Cristiana Couto Garcia, Rodrigo Guabiraba Brito, Florence Mara Rosa, José Carlos dos Reis and Selma Fernandes for the technical support rendered during the experiments. “
“Investigation was made of changes in immune system parameters during the course of neonatal infection. The study population consisted of 95 full-term neonates matched for chronological age and sex, divided into three groups: suspected infection (n = 20), sepsis (n = 25), infection-free control subjects (n = 50). Serial measurements were made of the cytokines interleukin-6 (IL-6), interleukin-1b (IL-1b) and tumour necrosis factor-α (TNF-α), lymphocyte subsets [CD3+, CD4+, CD8+, natural killer (NK) cells and B cells], the immunoglobulins (Ig) (IgG, IgM and IgA), C-reactive protein

(CRP), and the total blood count, before, 2 days after initiation of treatment and after stopping treatment (time periods first, second and third, respectively). IL6, TNF-α, IL1-b and CRP were higher at the first time period in the sepsis group, and IL6 and TNF-α continued to be higher in this group at the second period. IL-6 and TNF-α were precise sepsis predictors with sensitivity and specificity of 0.92, 0.98 and 0.91, 0.92, respectively. NK cells, B cells, CD3+, CD4+, CD8+ NVP-AUY922 concentration were higher in the sepsis and suspected infection groups, but the ratios CD3+/CD4+, CD3+/CD8+, CD4+/CD8+ showed no difference from the controls. IgG was lower and IgM higher in the sepsis group. In the control subjects CD3+, CD4+, CD8+ lymphocytes increased with increasing age. It is concluded that IL-6 and TNF are good diagnostic markers of sepsis in full-term neonates. Lymphocyte subsets were affected by both the clinical condition and the chronological age. NK and B cells may be

elevated in suspected and documented sepsis, and further studies are needed to determine their clinical significance. Neonates are vulnerable click here to bacterial infections, and sepsis is one of the major causes of neonatal morbidity and mortality. It is important to identify neonatal infection as early as possible, but clinical signs are usually unreliable in neonates, while the routine diagnostic tests lack precision [1]. The immune system of the neonate, although immature, reacts to infection in several ways. It produces acute phase reactants, such as C-reactive protein (CRP), cytokines, such as interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α), and reacts with changes in the white blood cell (WBC) populations.

Real-time reverse transcription–polymerase chain reaction (RT–PCR

Real-time reverse transcription–polymerase chain reaction (RT–PCR) was performed with the ABI 7900 HT (Applied

Biosystems) and PCR parameters were analysed according to the manufacturer’s protocol. Relative gene expression was calculated with the ΔΔCt method. PCR reactions for target genes and control were performed in triplicate for all samples. All statistical analyses were performed using spss software package version18. Comparisons between two independent groups were performed using the Mann–Whitney U-test or Student’s t-test. For cell culture experiments, statistical analyses were performed with one-way analysis of variance (anova) with Dunnett’s T3 or Tukey’s post-hoc click here tests. Data are presented as mean ± standard error of the mean (s.e.m.) and P < 0·05 was considered statistically significant. As a model for diabetes, we compared db/db mice with their lean controls. At 10 weeks of age, the db/db mice (on a C57BL/6 background) had increased

body weight, elevated plasma glucose and insulin levels, moderately increased levels of cholesterol and similar levels of triglycerides compared with control mice (Fig. 1a–d). In order to investigate if diabetes influenced immune cell distributions, PECs and splenocytes were collected and analysed with FACS. In the peritoneal cavity, the absolute numbers of B cells, T cells, macrophages, B-1a, B-1b and B-2 were significantly higher in the db/db mice than in control mice (Table 1), which Cyclin-dependent kinase 3 might reflect an increased

body weight and surface area in the peritoneal cavity of the db/db mice. Strikingly, the proportion of B-1a cells, expressed as percentages of total B cells, was lower in the db/db mice compared with the controls. The fraction of B-1b cells was similar in db/db mice and controls and, consequently, peritoneal B-2 cells expressed as a percentage of total B cells were higher in the db/db mice than in controls (Fig. 2). There were no differences in percentages of follicular B cells, MZB or B-1 cells in the spleen (Table 1). In conclusion, these results show that at steady state, db/db mice have a lower proportion of B-1a cells in the peritoneal cavity. In accordance with the overall increased absolute number of B cells in the db/db mice, the basal levels of total IgM and IgM against MDA-LDL were higher in db/db mice than control mice at 10 weeks of age (Table 1). In order to investigate if the decreased proportion of B-1a cells in diabetic mice is reflected by a blunted innate humoral response, db/db mice and controls (on a C57BL/6 background) were injected intraperitoneally with the TLR-4 agonist Kdo2-Lipid A. As expected, injection of Kdo2-Lipid A induced an increase in IgM against CuOx-LDL and MDA-LDL in plasma in both diabetic and control mice. The IgM response was lower in the db/db mice than in control mice, both at 3 and 7 days post-injection (Fig. 3a and b).

Retinoic acid also plays a key role in the balance of inflammator

Retinoic acid also plays a key role in the balance of inflammatory Th17 cells and suppressive Treg by inhibiting the formation of Th17 cells and enhancing the expression of FOXP3 through a STAT3/STAT5-independent signaling pathway 70. Several studies in humans have demonstrated that in healthy individuals, if an immune response to common environmental allergens is detectable, TR1 cells specific for such allergens represent the dominant subset 3, 6–8. Both healthy and allergic individuals Forskolin datasheet display allergen-specific Th1, Th2 and TR1 cells that recognize the same T-cell epitopes. Accordingly, depending on the predominant

subset and the balance between Th2 and TR1 cells, the individuals may develop allergy (Th2 predominance) or recovery (TR1 predominance). Two human models

have demonstrated that high-dose exposure to the offending allergens lead to tolerance induction 7, 71. Beekeepers are naturally highly exposed to bee venom allergens during the beekeeping season due to an increased number of bee stings. Kinase Inhibitor Library A reduction in T-cell-related cutaneous late-phase reactions and impaired capacity of allergen-specific T cells to proliferate and produce Th1 and Th2 cytokines is observed throughout the beekeeping season, reaching initial levels within 2 to 3 months after initial venom exposure. This regulation correlates with a clonal switch of venom antigen-specific Th1 and Th2 cells toward IL-10-secreting TR1 cells. In this model, histamine receptor 2 is upregulated on specific Th2 cells and plays a dual role in the suppression of allergen-stimulated T cells and contributes to increased IL-10 production 7. In another model of high-dose exposure to cat allergens, IgG4 Ab responses and IL-10-producing TR1 cells are either induced without subsequent

development of new sensitizations or asthma development 71. Supporting the protective role of Treg in allergy development, a recent study in mice has demonstrated that breast milk-mediated transfer of antigens to the neonate results in oral tolerance induction in an antigen-specific manner preventing allergic airway inflammation 72. This effect is mediated by Treg and depends on TGF-β signaling. Similarly, it was previously shown in humans that children who outgrew their milk allergy present a higher frequency of Treg and decrease in vitro proliferative responses to specific allergens than children who did not tolerate milk and displayed clinical symptoms of allergy after consumption 73. Allergen-SIT represents the single curative treatment in allergic diseases. It has been used for almost a century as a desensitization strategy by the repeated administration of increased doses of the causative allergen to induce a state of tolerance.

There are differences in the adaptations of tubular function in t

There are differences in the adaptations of tubular function in the early phase compared with the chronic phase following reduced renal mass. In several experimental models of reduced renal mass, fractional reabsorption of sodium is reduced acutely following nephrectomy but is rapidly restored to levels observed before nephrectomy.[37, 38] There are scant data available on compensatory adaptations in the acute phase in the human.

In one study, total sodium excretion was found to be similar to that observed before nephrectomy, by day 5 after uninephrectomy in kidney donors.[39] This adaptation was associated with a significant increase in lithium clearance (a semi-quantitative indicator of sodium PF-02341066 concentration reabsorption in the proximal tubules).[39] Similarly in the rat, it was demonstrated that at 2–5 hours after uninephrectomy, absolute reabsorption of sodium was similar to that of the sham controls but fractional proximal reabsorption of sodium had decreased significantly.[38]

By day 30 after nephrectomy in the rat, fractional proximal reabsorption had been restored to levels observed in sham animals.[38] Total reabsorption of sodium is maintained immediately after nephrectomy, while fractional proximal reabsorption is reduced. Thus, the distal tubules, where reabsorption of sodium has been shown to increase almost 90%,[10] are suggested to make a critical contribution to maintenance of sodium homeostasis during this period.[37] Restoration of proximal reabsorption of sodium after the aforementioned initial decrease is associated with a significant increase in activity of apical antiporters and the basolateral pump.[40] Glomerular hyperfiltration occurs in response to a reduction in renal mass and is associated with significant glomerular hypertrophy. In the adult human, within a few weeks after donation of a kidney, GFR reaches 70% of its value before nephrectomy[41, 42] and remains stable for up to

15–20 years.[8, 43] Similar observations were made in the rat where GFR stabilized at 80% of the pre-nephrectomy value by day 32 after nephrectomy.[38, 44] The hyperfiltration following a reduction in renal mass is associated with increased effective renal plasma flow,[41] likely due to decreased afferent during arteriolar resistance. Furthermore, following uninephrectomy in the rat, an increase in NO production has also been observed[45] which may promote the increase in renal blood flow and SNGFR following nephrectomy. Alterations in the TGF function likely contribute to the decrease in pre-glomerular resistance. Muller-Suur et al. showed that at 20 minutes after uninephrectomy in the adult rat, TGF sensitivity was reduced (rightward shift), but TGF reactivity was increased (downward shift) and the authors concluded that the decrease in TGF sensitivity may facilitate the rise in SNGFR following nephrectomy.[46] In contrast, Blantz et al.

Thus, it is possible that MZ B-cell differentiation is specifical

Thus, it is possible that MZ B-cell differentiation is specifically driven by BAFF. In support hereof, we observed a positive correlation between BAFF levels in WT and TCRβ/δ−/− mice, although due to the

small differences in BAFF levels the analysis failed to reach statistical significance (Pearson test: R2 = 0.29, p = 0.22, n = 7, data not shown). Due to the function of Act1 on BAFF responsiveness rather than BAFF production, we were unable to extend this analysis to Act1-deficient mice. Given the many known roles of Act1, Act1-deficient mice develop a complex phenotype involving many cell subsets. Even in B cells, Act1 appears to play multiple roles (i.e. control of CD40 and BAFF-R-signaling and responsiveness to IL-17A). Interestingly, it has been shown that IL-17A functions to increase B-cell survival, proliferation, and differentiation and hence supports the generation and persistence of autoreactive B cells [37]. As Act1 is a positive regulator of IL-17A signaling and a negative regulator of BAFF, it follows ALK inhibitor that the balance of Act1 binding to either IL-17R or BAFF-R is crucial for maintaining B-cell tolerance (Fig. 8). T-cell-deficient Act1-sufficient mice express very little IL-17A (data not shown), increased BAFF, and accelerated B cell

maturation (increased T2/T3, MZ, and FM), slightly elevated levels of anti-nuclear IgM antibodies and elevated deposition of IgM-IC in the kidney glomeruli (Fig. 8, bottom left panel). As expected all IgG and IgA production is abolished in the absence of T-cell help, that is, CD40 ligation (Fig. 8, bottom panels). Act1-deficiency on the other Amrubicin hand results in increased BAFF-mediated signaling driving T1 to T2/T3 B-cell maturation and elevated levels of MZ and FM B cells (Fig. 8, top right panel). We suggest that more self-reactive B cells (low BCR-antigen-binding affinity), which would normally have been deleted due to negative selection, survive, and differentiate as a result of BAFF hyperresponsiveness.

In addition, Act1-deficiency increases CD40L-mediated Ig class switching and the differentiation of IgG-secreting plasma cells hence elevated levels of IgG autoantibodies (Fig. 8, top right panel). Whether lack of IL-17-mediated signaling in the absence of Act1 is counteracting this effect by diminishing B-cell survival is currently unknown. Finally, when combining TCR deficiency with Act1 deficiency (TKO mice) it follows that BAFF-mediated signaling is increased leading to increased levels of T2/T3 immature B cells, MZ and FM B cells including cells with self-reactivity. CD40L-dependent class switching is eliminated by the lack of T cells resulting in elevated levels of IgM-secreting anti-nuclear-specific plasma cells (Fig. 8, bottom right panel). In conclusion, T-cell-deficient B6.

The authors declare no financial or commercial conflict of intere

The authors declare no financial or commercial conflict of interest. “
“Systemic lupus erythematosus (SLE) is an

autoimmune disease characterized by the presence of pathogenic IgG antinuclear antibodies. Pathogenic IgG autoantibody production requires B-cell activation, leading to the production of activation-induced deaminase (AID) and class switching of IgM genes to IgG. To understand how and when B cells are activated to produce these IgG autoantibodies, we studied cells from 564Igi, a mouse model of SLE. 564Igi mice develop a disease profile closely resembling that found in human SLE patients, including the presence of IgG antinucleic acid Abs. We have generated 564Igi mice that conditionally express an activation-induced cytidine deaminase transgene (Aicdatg), either in all B cells or only in mature B cells. Here, we show that class-switched pathogenic IgG autoantibodies were produced only in 564Igi mice in which AID was functional in early-developing B cells, resulting in loss of tolerance. Furthermore, we show that the absence of AID in early-developing B cells also results in increased production of self-reactive IgM, indicating Nutlin-3a cell line that AID, through somatic hypermutation, contributes to tolerance. Our results suggest that the pathophysiology of clinical SLE might also be dependent

on AID expression in early-developing B cells. “
“The novel immunosuppressant sotrastaurin is a selective inhibitor of protein kinase C isoforms that are critical in signalling pathways downstream of the T cell receptor. Sotrastaurin inhibits nuclear factor (NF)-κB, which directly promotes the transcription of forkhead box protein 3 (FoxP3), the key regulator for the development and function of regulatory T cells (Tregs). Our center participated in a randomized trial comparing sotrastaurin (n = 14) and the calcineurin inhibitor Neoral (n = 7) in renal transplant recipients. We conducted ex vivo mixed lymphocyte reaction (MLR) and flow cytometry HAS1 studies on these patient samples, as well as in vitro studies on samples

of blood bank volunteers (n = 38). Treg numbers remained stable after transplantation and correlated with higher trough levels of sotrastaurin (r = 0·68, P = 0·03). A dose-dependent effect of sotrastaurin on alloresponsiveness was observed: the half maximal inhibitory concentration (IC50) to inhibit alloactivated T cell proliferation was 45 ng/ml (90 nM). In contrast, Treg function was not affected by sotrastaurin: in the presence of in vitro-added sotrastaurin (50 ng/ml) Tregs suppressed the proliferation of alloactivated T effector cells at a 1:5 ratio by 35 versus 47% in the absence of the drug (P = 0·33). Signal transducer and activator of transcription 5 (STAT)-5 phosphorylation in Tregs remained intact after incubation with sotrastaurin.

3A) In conclusion, the humoral anti-peptide response of RA patie

3A). In conclusion, the humoral anti-peptide response of RA patients appeared more complex and less specific than the cellular anti-peptide response. In the present study, we found that a proportion of RA patients (21%) developed autoimmune T-cell responses specific for a major determinant contained in the sequence 117–133, which

is located in the second RNA-binding domain of hnRNP-A2. This proportion appears low at first sight but it should be considered that these patients had established disease and were treated with various immunomodulatory agents. Although some patients (11%) with osteoarthritis also reacted to the major T-cell epitope LBH589 nmr 120–133, it should be noted that these patients did not receive immunosuppressive medication. Therefore, the proportion of positive RA patients may be underestimated. The difficulty of identifying autoimmune T-cell epitopes is highlighted by a study on celiac disease, in which the patients had to be challenged Nutlin-3a order with gliadin to detect the dominant epitope 17.

The two peptides 117–133 and 120–133 preferentially recognized by PBMC from RA patients both contain the 9-mer core sequence 123–131 binding to various RA-associated HLA molecules, as determined by TEPITOPE analysis (Table 1 and Fig. 4). Nevertheless, only two patients reacted to both peptides (Table 2 and Supporting Information Table 2). This result may be linked to a differential presentation by various HLA molecules and recognition by various T-cell repertoires. Indeed, DR10 may present, and/or the selected T cell may recognize, 117–133 but not 120–133, and it would be the opposite for DR7,

whereas DR1-restricted T cells would recognize both peptides (Table 2). Since the sequence 117/120–133 binds to various RA-associated HLA alleles, it might be linked to pathogenicity in different ethnic populations. Indeed, DR*0101 and *0401 are present in Caucasians 1, whereas DR*1001 is often found in populations originating from the Mediterranean area, such as Spain, Greece, and Saudi Arabia 18–20. Moreover, HAS1 peptide 117/120–133 binds well to DR*0405 (Fig. 4), the major HLA-allele associated with severe and erosive RA in Japan 14. Although patients with SLE may also be reactive to the hnRNP-A2 antigen 21, it is unlikely that they recognize the RA dominant epitope 117/120–133, since susceptibility to lupus is associated to HLA-DR2 (DR15) and DR3 22 and peptides 117/120–133 are predicted extremely bad binders to these alleles (Fig. 4). The TEPITOPE program is best designed to accurately identify promiscuous epitopes, i.e. epitopes binding to many HLA class II molecules.