Cytotoxic T lymphocyte antigen 4 immunoglobulin modified dendritic cells attenuate allergic airway inflammation and hyperresponsiveness by regulating the development of T helper type 1 (Th1)/Th2 and Th2/regulatory T cell subsets in a murine model of asthma

Analysis of allergen components and identification of bioactivity of HSP70 in pollen of Populus deltoides

Background

Allergies caused by pollen from Populus deltoides are common, but the allergic components are still unclear.

Methods

The total proteins in pollen of P. deltoides were analyzed by proteomics, and the potential allergens were identified via the WHO/IUIS database and the allergenOnline database retrieval. One target protein was screened by bioinformatics and expressed in Escherichia coli. The biological activity of the expressed product was verified by animal experiments.

Results

The total of 3929 proteins in pollen of P. deltoides were identified, and 46 potential allergens belonging to 10 protein families were recognized by database retrieval. B9N9W6 protein of Hsp70 family was screened by bioinformatics analysis and expressed successfully. ELISA showed that B9N9W6 can stimulate the immune system to produce specific IgE and promote the generation of IL-4. Flow cytometry showed that B9N9W6 can significantly stimulate the proliferation of CD4⁺ T cells and promote the polarization of Th2 cells. The pathological sections of mice lung tissues indicated that alveolar destruction was more severe in the B9N9W6 group than that of extract group, and there were more inflammatory cells infiltration, mucus exudation and bleeding.

Conclusion

B9N9W6 is an important antigenic substance in the pollen of P. deltoides. Due to the conserved structure of Hsp70 family, more attention should be paid to the possibility of sensitization when Hsp70 from any pathogenic species is administered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12953-021-00178-8.

Effect of Biological Disease-modifying Anti-rheumatic Drugs on Airway and Interstitial Lung Disease in Patients with Rheumatoid Arthritis

Objective Biological disease-modifying anti-rheumatic drugs (bDMARDs) represent an important advance in alleviating rheumatoid arthritis (RA), but their effect on rheumatic airway disease (AD) and interstitial lung disease (ILD) is still unclear. This study was performed to evaluate the association of the use of different bDMARDs with new-onset or worsening of RA-AD/ILD. Methods We performed a retrospective cohort study of RA patients who received bDMARDs and assessed their AD/ILD before and after drug initiation in our hospital over the past 10 years. We evaluated the serial changes in computed tomography (CT), classified patients according to AD/ILD progression, and analyzed associations between clinical characteristics and outcomes. Results We enrolled 49 patients. Thirty patients received tumor necrosis factor inhibitors (TNFis), 12 received abatacept (ABT), and the remaining 7 received tocilizumab (TCZ). Seventeen patients had ILD, 10 had AD, and 6 had both AD and ILD before the initiation of bDMARDs. New emergence or exacerbation of AD/ILD was observed in 18 patients after drug initiation, while the remaining 31 remained stable or improved. Multiple logistic regression analyses revealed that pre-existing AD was an independent risk factor against the emergence or exacerbation of RA-AD/ILD, and ABT use was a protective factor against it. Conclusion Our study showed that pre-existing RA-AD is associated with future worsening of RA-AD/ILD, and ABT over other bDMARDs was associated with a better prognosis. Future studies to confirm our results are needed.

A meta-analysis of the association between CTLA-4 genetic polymorphism and susceptibility of asthma

BACKGROUND

Numerous studies have reported an association between cytotoxic T-lymphocyte associated antigen 4 gene (CTLA4) polymorphism and susceptibility to asthma, in different populations, but the results have been inconsistent. We performed a meta-analysis of 19 published case-control studies to obtain a reasonably accurate estimation of the relationship between CTLA4 polymorphism and asthma.

METHODS

We searched the Pubmed, EMBASE, Chinese National Knowledge Infrastructure, and Wanfang databases and extracted data from 19 independent, eligible studies. Odds ratios (ORs) with 95% confidence intervals (CIs) and Egger test were separately used to assess the strength of associations and publication bias.

RESULTS

A total of 19 case-control studies involving 4831 cases and 4534 controls were identified. The combined results revealed that there was significant association between the +49A/G polymorphism and asthma (for GG + GA vs. AA: OR = 0.82, 95% CI = 0.70-0.97, P = .02). Stratification by race or age indicated a significant association between the CTLA-4 +49 GA+GG genotype and asthma in Asians (OR = 0.80, 95% CI = 0.68-0.95, P = .01) and children (OR = 0.75, 95% CI = 0.62-0.90, P = .002), but there was no association in whites (OR = 0.94, 95% CI = 0.80-1.10, P = .44) and adults (OR = 0.85, 95% CI = 0.68-1.06, P = .15). Additionally, there was a significant association with atopic asthma under the random-effects model (OR = 0.81, 95% CI = 0.67-0.98, P = .03). In addition, there was no significant association between the -318 C/T polymorphism and asthma risk.

CONCLUSIONS

Our meta-analysis results suggested that the +49A/G polymorphism in CTLA-4 was an important risk factor for asthma susceptibility, especially in Asian individuals, children, and atopic patients.

Lipopolysaccharide Exposure Alleviates Asthma in Mice by Regulating Th1/Th2 and Treg/Th17 Balance

Background

It is generally believed that endotoxin exposure exacerbates risk of developing asthmatic symptoms. However, recent studies have indicated that prior bacterial exposure may prevent future symptoms of asthma. Here, we evaluated the influence of pre-exposure to different concentrations of lipopolysaccharide (LPS) to subsequent ovalbumin (OVA) allergen sensitization and challenge.

Material/Methods

Four-week-old Balb/c mice were treated intranasally with varying concentrations of LPS (1 ug, 10 ug, and 100 ug) or sterile PBS for 10 days, then 2 weeks later they were exposed to OVA. Both the molecular and functional airway responses to OVA administration were assessed following prior exposure to different doses of LPS or controls. Additionally, the Th1/Th2 and Treg/Th17 balance was measured.

Results

Airway responsiveness and immune cell recruitment in the bronchoalveolar lavage (BALF) were decreased in animals exposed to a low dose of LPS (1 ug) treatment compared with the asthma group. Moderate-dose (10 ug) and high-dose (100 ug) LPS administration showed no differences from controls. Further, low-dose LPS (1 ug) exposure was associated with increased Th1 cytokines, T-bet, Treg cytokine (IL-10, TGF-β), and Foxp3 expression, but decreased Th2 cytokines (IL-4,5,13), GATA3, Th17, and ROR-γt expression compared with the asthma group. Finally, higher numbers of CD4+CD25+Foxp3+Treg cells, and CD4+INF-γ+T cells, and lower CD4+IL-4+T cells and CD4+IL-17+T cells were observed in the low-dose LPS-treated groups compared to controls.

Conclusions

Our findings suggest that prior exposure to low doses of LPS may protect from OVA-induced airway hyperresponsiveness (AHR) and histopathologic changes through regulation of the Th1/Th2 and Treg/Th17 balance.

Influences of PON1 on airway inflammation and remodeling in bronchial asthma

This study aims to explore the influences of Paraoxonase-1 (PON1) involved in airway inflammation and remodeling in asthma. Mice were divided into control, asthma, asthma + PON1 and asthma + NC groups, and asthma models were established via aerosol inhalation of ovalbumin (OVA). HE, Masson, and PAS stains were used to observe airway inflammation and remodeling, Giemsa staining to assess inflammatory cells in bronchoalveolar lavage fluid (BALF), qRT-PCR and Western blot to detect PON1 expression, lipid peroxidation and glutathione assays to quantify malondialdehyde (MDA) activity and glutathione peroxidase (GSH) levels, ELISA to determine inflammatory cytokines and immunoglobulin, and colorimetry to detect PON1 activities. Additionally, mice lung macrophages and fibroblasts were transfected with PON1 plasmid in vitro; ELISA and qRT-PCR were performed to understand the effects of PON1 on inflammatory cytokines secreted by lung macrophages, MTT assay for lung fibroblasts proliferation and qRT-PCR and Western blot for the expressions of PON1, COL1A1, and fibronectin. After overexpression of PON1, the asthma mice had decreased inflammatory cell infiltration, fibrosis degree, and airway wall thickness; inflammatory cells and inflammatory cytokines in BALF were also reduced, expressions of OVA-IgE and IgG1, and MDA activity were decreased, but the expressions of OVA-IgG2a and INF-γ and GSH levels were increased. Besides, PON1 significantly inhibited microphage expression of LPS-induced inflammatory cytokines, lung fibroblast proliferation, and COL1A1 and fibronectin expression. Thus, PON1 could relieve airway inflammation and airway remodeling in asthmatic mice and inhibit the secretion of LPS-induced macrophage inflammatory cytokines and the proliferation of lung fibroblasts.

dNP2-ctCTLA-4 inhibits German cockroach extract-induced allergic airway inflammation and hyper-responsiveness via inhibition of Th2 responses

German cockroaches are major household allergens that can trigger allergic airway inflammatory diseases with sensitive T-cell responses. Although the use of immune modulatory biologics, such as antibodies, to mediate allergic responses has recently been examined, only systemic administration is available because of the size limitations on intranasal administration. Here we utilized a cell-permeable peptide, dNP2, to deliver the cytoplasmic domain of cytotoxic T-lymphocyte antigen-4 (ctCTLA-4) through the airway epithelium to modulate Th2 responses in a German cockroach extract (GCE)-induced allergic airway inflammation model. The intranasal delivery efficiency of the dNP2-dTomato protein to the lungs was higher in GCE-induced asthmatic lung parenchymal cells compared to the sham cells. Intranasal administration of the dNP2-ctCTLA-4 protein inhibited airway hyper-responsiveness and reduced airway inflammation and remodeling, including goblet cell metaplasia and collagen deposition around the bronchi. The number of infiltrated cells, including eosinophils, and the levels of IL-4, IL-5, IL-13 and IFN-γ in the lungs were significantly reduced, presumably owing to inhibition of Th2 differentiation. However, intranasal administration of CTLA4-Ig did not inhibit airway inflammation. These results collectively suggest that dNP2-ctCTLA-4 is an efficient intranasally applicable candidate biologic for treating allergic asthma.

Thermoneutral housing temperature regulates T-regulatory cell function and inhibits ovabumin-induced asthma development in mice

The change in ambient temperature is one of the risk factors for the aggravation of bronchial asthma (BA). Yet, whether the ambient temperature influences the immune functions associated with allergic asthma remains unknown. In this study, we treated asthmatic mice with standard temperature (ST, 20 °C) or thermoneutral temperature (TT, 30 °C). The results showed that the airway inflammatory cell counts in bronchoalveolar lavage fluid (BALF) and airway hyperresponsiveness (AHR) were significantly reduced in the mice treated with TT as compared with the mice treated with ST. The imbalance of Th1/Th2 response in the lung was improved following housing the mice at TT. In addition, the pulmonary Treg cells were increased in asthmatic mice after TT treatment. The temperature stress (29 °C and 41 °C) drove naïve CD4T cells towards Th2 cells. Our data demonstrate that the change of ambient temperature was a risk factor to aggravate experimental asthma.

Improvement in allergic and nonallergic rhinitis: A secondary benefit of adenoidectomy in children

Chronic rhinitis (CR) is a common disorder in children. Allergic rhinitis (AR) is a risk factor for CR, and children with AR tend to suffer more from hypertrophic adenoids than do patients with nonallergic rhinitis (NAR). Few studies have addressed the issue of alleviating symptoms of pediatric CR or AR following adenoidectomy alone. We conducted a retrospective chart review to determine whether CR in children improves after adenoidectomy and whether children with AR will benefit more than those with NAR. Charts of 47 children who had undergone adenoidectomy for nasal obstruction and chronic middle ear effusion were reviewed. AR and NAR subgroups were classified based on symptoms, signs, blood IgE, and nasal smear (allergic criteria). Hypertrophic adenoids were graded using the adenoid-to-nasopharyngeal ratio (ANr >0.8). A questionnaire was used to assess the change in chronic rhinitis postoperatively. Improvement in CR was reported in 37 of 47 (79%) children. Patients with AR improved to a higher extent than those with NAR (12 of 14 [86%] vs. 25 of 33 [76%], respectively), but the difference was not statistically significant. A total of 41 lateral postoperative nasopharyngeal x-rays were obtained. The x-rays revealed that 20 of 26 (77%) of patients with ANr >0.8 had complete and 4 of 26 (15%) had partial resolution of symptoms of CR for a total resolution rate of 92%, compared to only a 53% resolution in the ANr <0.8 subgroup (6 of 15 and 2 of 15 patients, respectively [p <0.05]). The correlation between adenoid size and resolution of CR was not related to any of the AR/NAR subgroups. We conclude that symptoms of CR may improve after adenoidectomy in children who are experiencing nasal obstruction and chronic otitis media with effusion. Clinical improvement did not differ between AR and NAR patients, and was more prominent in children with hypertrophic adenoids (ANr >0.8).

Ligustrazine attenuates inflammation and the associated chemokines and receptors in ovalbumine-induced mouse asthma model

Ligustrazine which is isolated from Chinese herb ligusticum chuanxiong hort, has been widely used in traditional Chinese medicine (TCM) for asthma treatment. In this study, we aim to observe the effect of ligustrazine on inflammation and the associated chemokines and receptors in ovalbumin (OVA)-induced mouse asthma model. Our data demonstrates that ligustrazine suppresses airway hyperresponsiveness to methacholine and lung inflammation in OVA-induced mouse asthma model. Ligustrazine also induces inhibition of inflammatory cells including neutrophils, lymphocytes and eosinophils. In addition, ligustrazine significantly reduces IL-4, IL-5, IL-17A, CCL3, CCL19 and CCL21 level in BALF of asthma mice. Furthermore, ligustrazine induces down-regulation of CCL19 receptor CCR7, STAT3 and p38 MAPK protein expression. Collectively, these results suggest that ligustrazine is effective in attenuation of allergic airway inflammatory changes and related chemokines and receptors in OVA-induced asthma model, and this action might be associated with inhibition of STAT3 and p38 MAPK pathway, which indicates that ligustrazine may be used as a potential therapeutic method to treat asthma.

Bronchial lesions of mouse model of asthma are preceded by immune complex vasculitis and induced bronchial associated lymphoid tissue (iBALT)

We systematically examined by immune histology the lungs of some widely used mouse models of asthma. These models include sensitization by multiple intraperitoneal injections of soluble ovalbumin (OVA) or of OVA with alum, followed by three intranasal or aerosol challenges 3 days apart. Within 24 h after a single challenge there is fibrinoid necrosis of arterial walls with deposition of immunoglobulin (Ig) and OVA and infiltration of eosinophilic polymorphonuclear cells that lasts for about 3 days followed by peribronchial B-cell infiltration and slight reversible goblet cell hypertrophy (GCHT). After two challenges, severe eosinophilic vasculitis is present at 6 h, increases by 72 h, and then declines; B-cell proliferation and significant GCHT and hyperplasia (GCHTH) and bronchial smooth muscle hypertrophy recur more prominently. After three challenges, there is significantly increased induced bronchus-associated lymphoid tissue (iBALT) formation, GCHTH, and smooth muscle hypertrophy. Elevated levels of Th2 cytokines, IL-4, IL-5, and IL-13, are present in bronchial lavage fluids. Sensitized mice have precipitating antibody and positive Arthus skin reactions but also develop significant levels of IgE antibody to OVA but only 1 week after challenge. We conclude that the asthma like lung lesions induced in these models is preceded by immune complex-mediated eosinophilic vasculitis and iBALT formation. There are elevations of Th2 cytokines that most likely produce bronchial lesions that resemble human asthma. However, it is unlikely that mast cell-activated atopic mechanisms are responsible as we found only a few presumed mast cells by toluidine blue and metachromatic staining limited to the most proximal part of the main stem bronchus, and none in the remaining main stem bronchus or in the lung periphery.

Immunosuppression in early postnatal days induces persistent and allergen-specific immune tolerance to asthma in adult mice

Bronchial asthma is a chronic airway inflammatory condition with high morbidity, and effective treatments for asthma are limited. Allergen-specific immunotherapy can only induce peripheral immune tolerance and is not sustainable. Exploring new therapeutic strategies is of great clinical importance. Recombinant adenovirus (rAdV) was used as a vector to make cells expressing cytotoxic T lymphocyte-associated antigen-4-immunoglobulin (CTLA4Ig) a soluble CTLA4 immunoglobulin fusion protein. Dendritic cells (DCs) were modified using the rAdVs together with allergens. Then these modified DCs were transplanted to mice before allergen sensitization. The persistence and specificity of immune tolerance were evaluated in mice challenged with asthma allergens at 3 and 7 months. DCs modified by CTLA4Ig showed increased IL-10 secretion, decreased IL-12 secretion, and T cell stimulation in vitro. Mice treated with these DCs in the early neonatal period developed tolerance against the allergens that were used to induce asthma in the adult stage. Asthma symptoms, lung damage, airway reactivity, and inflammatory response all improved. Humoral immunity indices showed that this therapeutic strategy strongly suppressed mice immune responses and was maintained for as long as 7 months. Furthermore, allergen cross-sensitization and challenge experiments demonstrated that this immune tolerance was allergen-specific. Treatment with CTLA4Ig modified DCs in the early neonatal period, inducing persistent and allergen-specific immune tolerance to asthma in adult mice. Our results suggest that it may be possible to develop a vaccine for asthma.

Effect of xinfeng capsule on pulmonary function in a adjuvant arthritis rat model

OBJECTIVE

To observe the relationship between reduced pulmonary function and regulatory T cells (Tregs) and helper T cells (Th)1/Th2 drift in a rat model of adjuvant arthritis (AA), and to study the impact of Xinfeng capsule (XFC) on pulmonary function and investigate the mechanism of action.

METHODS

Forty rats were randomly divided into normal control group (NC), model control group (MC), Tripterygium glycosides tablet group (TPT), and XFC group, with 10 in each. Except for the NC group, AA was induced in all rats by intracutaneous injection of 0.1 mL Freund's complete adjuvant in the right paw. On the 19th day after modeling, the NC and MC groups were given physiological saline (0.9%), while the TPT and XFC groups were given TPT (10 mg/kg) and XFC (2.4 g/kg), once daily, respectively. Thirty days after administration, changes in paw swelling, arthritis index (AI), pulmonary function, levels of serum gamma-interferon (IFN-gamma) and interleukin (IL)-4, Tregs in peripheral blood, and IFN-gamma, IL-4, Forkhead box transcription factor 3 (FoxP3) in lung tissue were observed by enzyme-linked immunosorbent assay, flow cytometry, polymerase chain reaction, and western blot.

RESULTS

Compared with the NC group, paw swelling, AI, IFN-gamma, and Th1/Th2 were increased, and pulmonary function parameters, IL-4, FoxP3 were decreased significantly in the MC group (P < 0.05 or P < 0.01). Pulmonary function parameters, Treg, IL-4, FoxP3 (and mRNA) were higher, and paw swelling, AI, and IFN-gamma (and mRNA) were lower in the XFC group than those in the MC group. The XFC group was also much better than the TPT group in improving pulmonary function, FoxP3 mRNA, IFN-gamma, IL-4, Th1/Th2, and IL-10 (P < 0.05 or P < 0.01).

CONCLUSION

Xinfeng capsule can improve pulmonary function by regulating the levels of Tregs, inhibiting the activation of Th1 to Th2 cells, inducing drift, maintaining cell immune suppression, correcting the imbalance of Th1/Th2, and reducing inflammatory mediators.

T lymphocyte antigen 4-modified dendritic cell therapy for asthmatic mice guided by the CCR7 chemokine receptor

The CD80/CD86-CD28 axis is a critical pathway for immuno-corrective therapy, and the cytotoxic T lymphocyte antigen 4 (CTLA4) is a promising immunosuppressor targeting the CD80/CD86-CD28 axis; however, its use for asthma therapy needs further optimization. A human CTLA4 fused with the IgCγ Fc (CTLA4Ig) and mouse CC chemokine receptor type7 (CCR7) coding sequences were inserted into a recombinant adenovirus (rAdV) vector to generate rAdV-CTLA4Ig and rAdV-CCR7. The naive dendritic cells (DCs) were infected with these rAdVs to ensure CCR7 and CTLA4Ig expression. The therapeutic effects of modified DCs were evaluated. rAdV-CTLA4Ig and rAdV-CCR7 infected DCs improved all asthma symptoms. Inflammatory cell infiltration and cytokine analysis showed that rAdV-CTLA4Ig and rAdV-CCR7-modified DC therapy reduced the number of eosinophils and lymphocyte and neutrophil infiltration in the lung. Interestingly, assessment of the humoral immunity showed that the IL-4 and IFNγ levels of the rAdV-CTLA4Ig and rAdV-CCR7-modified DC-treated mice decreased significantly and did not reverse the Th1/Th2 balance. DCs expressing CCR7 displayed guidance ability for DC migration, primarily for DCs in the inflammatory lung. Additionally, the rAdVs caused an inflammatory response by inducing DC differentiation, inflammatory cell infiltration and changes in cytokines; however, mice transplanted with rAdV-green fluorescent protein (GFP)-infected DCs displayed no asthma manifestations. In conclusion, CTLA4Ig-modified DCs exhibited a therapeutic effect on asthma, and CCR7 may guide DC homing. The combination of these two molecules may be a model for precision-guided immunotherapy.

A DNA vaccine encoding a chimeric allergen derived from major group 1 allergens of dust mite can be used for specific immunotherapy

Immunization with DNA-based constructs has been shown to be against the antigen and the response is skewed in such a way as to ameliorate the symptoms of allergic disease. This approach is particularly useful in the treatment of allergic inflammatory diseases, such as asthma. The major group 1 allergen from house dust mites is one of the triggers of allergic asthma. This study explores whether a chimeric gene R8, derived from the major group 1 allergen of house dust mite species (Dermatophagoides farinae and Dermatophagoides pteronyssinus), can be expressed in Human Embryonic Kidney 293 cells (HEK 293 T) and whether such a construct can be used as a DNA vaccine in asthma therapy. The eukaryotic expression vector pcDNA3.1 was used to express the R8 molecule in HEK 293 T cells and successful expression of R8 was confirmed using a fluorescence microscope and western blot analysis. The efficacy of R8 as DNA vaccine was also assessed in a mouse asthma model. The in vivo data showed that R8 rectified the TH1/TH2 imbalance typical of allergic inflammation and stimulated the proliferation of regulatory T (Treg) cells. Immunization with the R8 construct also decreased serum allergen-specific IgE production in this mouse asthma model. Our findings suggest that R8 may be a feasible potential DNA vaccine for specific immunotherapy (SIT) in the treatment of allergic asthma.

Infant 7-valent pneumococcal conjugate vaccine immunization alters young adulthood CD4(+)T cell subsets in allergic airway disease mouse model

7-Valent pneumococcal conjugate vaccine (PCV7) immunization in adulthood can inhibit allergic asthma in mouse model. The aim of this study is to investigate the effects of infant PCV7 immunization on young adulthood CD4(+)T cell subsets in a murine allergic airway disease (AAD) model. Our study indicated that infant PCV7 immunization can inhibit young adulthood airway inflammation and airway hyperresponsiveness (AHR) by inducing the production of Foxp3(+)Treg, Th1 cells and their cytokines IL-10 and IFN-γ, inhibiting the production of Th2, Th17 cells and their cytokines IL-13 and IL-17A in BALB/c mice model. These results suggested that infant PCV7 immunization may serve as an effective measure to prevent young adulthood mice AAD.

Psychological stress in children may alter the immune response

Psychological stress is a public health issue even in children and has been associated with a number of immunological diseases. The aim of this study was to examine the relationship between psychological stress and immune response in healthy children, with special focus on autoimmunity. In this study, psychological stress was based on a composite measure of stress in the family across the domains: 1) serious life events, 2) parenting stress, 3) lack of social support, and 4) parental worries. PBMCs, collected from 5-y-old high-stressed children (n = 26) and from 5-y-old children without high stress within the family (n = 52), from the All Babies In Southeast Sweden cohort, were stimulated with Ags (tetanus toxoid and β-lactoglobulin) and diabetes-related autoantigens (glutamic acid decarboxylase 65, insulin, heat shock protein 60, and tyrosine phosphatase). Immune markers (cytokines and chemokines), clinical parameters (C-peptide, proinsulin, glucose), and cortisol, as an indicator of stress, were analyzed. Children from families with high psychological stress showed a low spontaneous immune activity (IL-5, IL-10, IL-13, IL-17, CCL2, CCL3, and CXCL10; p < 0.01) but an increased immune response to tetanus toxoid, β-lactoglobulin, and the autoantigens glutamic acid decarboxylase 65, heat shock protein 60, and tyrosine phosphatase (IL-5, IL-6, IL-10, IL-13, IL-17, IFN-γ, TNF-α, CCL2, CCL3, and CXCL10; p < 0.05). Children within the high-stress group showed high level of cortisol, but low level of C-peptide, compared with the control group (p < 0.05). This supports the hypothesis that psychological stress may contribute to an imbalance in the immune response but also to a pathological effect on the insulin-producing β cells.