Inhibition of rheumatoid arthritis by blocking connective tissue growth factor

Association of Pro-Inflammatory Cytokines with Vitamin D in Hashimoto's Thyroid Autoimmune Disease

Background and objectives: Hashimoto's thyroiditis is an important autoimmune thyroid condition. It is characterized by lymphocytic congestion of the thyroid gland followed by progressive deterioration and fibrous substitution of the thyroid in the parenchymal structure. This study has provided insight into the variations of blood pro-inflammatory cytokine levels in patients with Hashimoto's disease and the key role of vitamin D levels among selected patients. Materials and Methods: A total of 144 participants including healthy controls and patients were studied in the current study in which 118 were female and 26 were male. The thyroid profile was evaluated in patients with Hashimoto's thyroiditis and healthy controls. Results: The mean ± SD Free T4 in the patients was recorded as 14.0 ± 4.9 pg/mL, and TSH was 7.6 ± 2.5 IU/L, whereas the median ± IQR thyroglobulin antibodies (anti-TG) were 285 ± 142. Thyroid peroxidase antibodies (anti-TPO) were 160 ± 63.5, whereas in the healthy controls, the mean ± SD Free T4 was recorded as 17.2 ± 2.1 pg/mL, and TSH was 2.1 ± 1.4 IU/L, whereas the median ± IQR anti-TGs were 56.30 ± 46.06, and anti-TPO was 5.6 ± 5.12. The assessment of pro-inflammatory cytokines (pg/mL) and total Vitamin D levels (nmol/L) in patients with Hashimoto's thyroiditis was recorded with values IL-1B 6.2 ± 0.8, IL-6 9.4 ± 0.4, IL-8 7.5 ± 0.5, IL-10 4.3 ± 0.1, IL-12 3.8 ± 0.5, TNF-α 7.6 ± 1.1, and total vitamin D 21.89 ± 3.5, whereas in healthy controls the mean ± SD IL-1B was 0.6 ± 0.1, IL-6 2.6 ± 0.5, IL-8 3.0 ± 1.2, IL-10 3.3 ± 1.3, IL-12 3.4 ± 0.4, TNF-α 1.4 ± 0.3 and total vitamin D was 42.26 ± 5.5. Conclusions: It was found that individuals with Hashimoto's thyroiditis had raised serum levels of IL-1B, IL-6, IL-8, IL-10, IL-12, and TNF-α as compared to the healthy controls, whereas the total vitamin D levels were remarkably low as compared to health controls. Serum TSH, anti-TG, and anti-TPO levels were typically lower in controls and much higher in individuals with Hashimoto's thyroiditis. The current study's findings might aid in future studies and in the diagnosis and management of autoimmune thyroid disease.

HOTAIR and THRIL Long Non Coding RNAs and Their Target Genes in Rheumatoid Arthritis patients

BACKGROUND

Rheumatoid arthtritis (RA) is a chronic systemic inflammatory autoimmune disease characterized by irreversible joint damage and deformity. The aim of this study is to investigate THRIL and HOTAIR serum expression and their target genes in Egyptian RA patients and to evaluate their relationship to the clinico-pathological data.

METHODS

The present study included fifty-two RA patients and fifty-six healthy controls. RA patients were classified according to DAS28 score. All subjects were subjected to full history taking and clinical examination. Quantitative real time PCR was done to estimate the expression levels of serum THRIL and HOTAIR as well as their target genes tumor necrosis factor alpha (TNF-α) and metalloproteinase 2 (MMP-2) were estimated by ELISA techniques.

RESULTS

Results revealed that both THRIL and HOTAIR were statistically over expressed in RA patients compared to healthy group with p-value< 0.05. Results showed as well that the target genes for those long-non coding RNAs, TNF-α and MMP-2, were also significantly higher in RA patients compared to healthy controls.

CONCLUSION

Both THRIL and HOTAIR associated with their target genes, can be considered as diagnostic markers for RA.

The protein-protein interaction between connective tissue growth factor and annexin A2 is relevant to pannus formation in rheumatoid arthritis

Background

Connective tissue growth factor (CTGF)-induced angiogenesis is a crucial factor in rheumatoid arthritis (RA), but CTGF-interacting protein and related molecular mechanism of their interaction have not been fully elucidated.

Methods

CTGF-interacting proteins were identified through the LC-MS/MS analysis of the Co-IP products from fibroblast-like synoviocyte (FLS) lysates, and the interaction between CTGF and annexin A2 (ANXA2) was further confirmed through Co-IP and BiFC assay. The binding domain, mutant, mechanism, and angiogenesis function were assessed by homology modeling, molecular docking, MTT, cell scratch, tube formation, and chick chorioallantoic membrane (CAM) assays. Additionally, severe combined immunodeficiency (SCID) mouse co-implantation model was constructed to confirm the effect of ANXA2/CTGF-TSP1 in the process of RA in vivo.

Results

ANXA2 was identified and verified as an interaction partner of CTGF for the first time by Co-IP and LC-MS/MS analysis. Co-localization of CTGF and ANXA2 was observed in RA-FLS, and direct interaction of the TSP-1 domain of CTGF and ANXA2 was determined in HEK293T cells. The spatial conformation and stable combination of the ANXA2/CTGF-TSP1 complex were assessed by homology modeling in the biomimetic environment. The function of the ANXA2/CTGF-TSP1 complex was proved on promoting FLS proliferation, migration, and angiogenesis in vitro and deteriorating FLS invasion and joint damage in SCID mice.

Conclusions

TSP-1 is the essential domain in CTGF/ANXA2 interaction and contributes to FLS migration and pannus formation, inducing the process of RA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02656-y.

CCN proteins in the musculoskeletal system: current understanding and challenges in physiology and pathology

The acronym for the CCN family was recently revised to represent “cellular communication network”. These six, small, cysteine-enriched and evolutionarily conserved proteins are secreted matricellular proteins, that convey and modulate intercellular communication by interacting with structural proteins, signalling factors and cell surface receptors. Their role in the development and physiology of musculoskeletal system, constituted by connective tissues where cells are interspersed in the cellular matrix, has been broadly studied. Previous research has highlighted a crucial balance of CCN proteins in mesenchymal stem cell commitment and a pivotal role for CCN1, CCN2 and their alter ego CCN3 in chondrogenesis and osteogenesis; CCN4 plays a minor role and the role of CCN5 and CCN6 is still unclear. CCN proteins also participate in osteoclastogenesis and myogenesis. In adult life, CCN proteins serve as mechanosensory proteins in the musculoskeletal system providing a steady response to environmental stimuli and participating in fracture healing. Substantial evidence also supports the involvement of CCN proteins in inflammatory pathologies, such as osteoarthritis and rheumatoid arthritis, as well as in cancers affecting the musculoskeletal system and bone metastasis. These matricellular proteins indeed show involvement in inflammation and cancer, thus representing intriguing therapeutic targets. This review discusses the current understanding of CCN proteins in the musculoskeletal system as well as the controversies and challenges associated with their multiple and complex roles, and it aims to link the dispersed knowledge in an effort to stimulate and guide readers to an area that the writers consider to have significant impact and relevant potentialities.

Diagnostic value of serum connective tissue growth factor in rheumatoid arthritis

Serum connective tissue growth factor (CTGF) is reported to be a potential biomarker for the diagnosis of rheumatoid arthritis (RA). Our study aimed to investigate the prevalence of serum CTGF and the association with the clinical features in RA patients. Serum samples were obtained from 180 patients with RA, 168 patients with other rheumatic diseases, including 43 systemic lupus erythematosus (SLE), 34 osteoarthritis (OA), 17 primary Sjögren's syndrome (pSS), 20 ankylosing spondylitis (AS), 23 psoriatic arthritis (PsA), 6 reactive arthritis (ReA), 20 systemic sclerosis (SSc), and 5 systemic vasculitis (SV), and 64 healthy individuals. The clinical and laboratory data of patients with RA were collected. Levels of CTGF in serum were measured by enzyme linked immunosorbent assay (ELISA). Associations between CTGF and the clinical features of RA were analyzed. The positivity of serum CTGF among RA patients (33.89%) was significantly higher than those of SLE (9.3%), OA (0%), AS (0%), pSS (0%), PsA (0%), ReA (0%), SSc (5%), SV (0%), and healthy controls (4.69%) (p < 0.0001). The mean concentration of serum CTGF in RA was also significantly higher than those in other rheumatic diseases and healthy controls (p < 0.001). At the cut-off value of 263.30 pg/ml, the sensitivity, specificity, positive predictive value, and negative predictive value of serum CTGF for RA were 33.89%, 96.55%, 88.41%, and 55.45%, respectively. Anti-cyclic citrullinated peptide (anti-CCP) antibody (p < 0.001), rheumatoid factor (RF) (p < 0.001), IgG (p = 0.025), and IgM (p = 0.004) in CTGF-positive patients were higher than those in CTGF-negative patients. Besides, the positive rate of serum CTGF was significantly higher in RA patients with interstitial lung disease (ILD) (53.1%, 26/49) than RA-non-ILD patients (26.7%, 35/131, p = 0.003). Serum CTGF, as a novel biomarker, has certain diagnostic value for RA. Further studies are necessary to get more knowledge for the diagnostic performance of CTGF in RA. KEY POINTS: • Serum CTGF, as a novel biomarker, has certain diagnostic value for RA, the sensitivity, specificity, positive predictive value, and negative predictive value of which were 33.89%, 96.55%, 88.41%, and 55.45%, respectively. • Serum CTGF was more common to be positive in RA-ILD patients (53.1%, 26/49) than RA-non-ILD patients (26.7%, 35/131, p = 0.003).

Vitamin D as a Key Player in Modulating Rheumatoid Arthritis-derived Immune Response

Rheumatoid arthritis (RA) is a systemic inflammatory disease with chronic nature of joints related to autoimmunity. Vitamin D was found to modulate cell growth, function of immune cells and anti-inflammatory action. The aims of that study were to investigate serum level of vitamin D and some cytokines and to identify the correlation between vitamin D and these cytokines in RA. Totally 40 RA patients without vitamin D supplement were involved in this study. Serum level of vitamin D, interleukin-6 (IL-6), IL-10, IL-35, C-reactive protein (CRP) and tumor necrosis factor α (TNF-α), all of them were measure in all patients by enzyme-linked immunosorbent assay (ELISA). Patients were classified according to Vitamin D levels into two groups; RA patients with Vit. D deficiency (n=25) and RA patients with Vit. D sufficiency (n=15). IL-6 was lower significantly (P = 0.03) in RA patients with Vit. D sufficiency than RA patients with Vit. D deficiency. IL-10 and IL-35 were higher significantly (P = 0.0234, P = 0.0356 respectively) in RA patients with Vit. D sufficiency than RA patients with Vit. D deficiency. Vit. D was significantly positively correlated with both IL-10 (r = 0.4516, P = 0.0034) and IL-35 (r = 0.3424, P = 0.0329) and negatively correlated with IL-6 (r = -0.3188, P = 0.0479). Sufficient serum level of Vit. D is correlated with higher level of anti-inflammatory cytokines (IL-10 and IL-35) and lower level of IL-6. This support the immunomodulatory effect of Vit. D in RA.

Clinical significance of CCN2/connective tissue growth factor in Behçet's disease patients

AIM

Behçet's disease (BD) is a chronic autoimmune vasculitic disorder of unclear pathogenesis. CCN2/CTGF (connective tissue growth factor) is one of the CCN family members which carry out pro-angiogenic biological functions and play an important role in inflammatory and autoimmune diseases. The aim of the present study was to assess CCN2 plasma concentrations in BD patients and to analyze their association with clinical features of the disease, activity and laboratory parameters.

METHODS

We included 87 BD patients and 60 healthy control subjects matched for age and gender. Demographic, clinical, disease activity and severity data were recorded. Plasma CCN2 concentrations were measured using enzyme-linked immunosorbent assay.

RESULTS

The plasma concentrations of CCN2 in BD patients were significantly elevated compared to healthy controls. The mean plasma CCN2 levels in patients with major organ involvement were significantly higher than those without. Patients who received steroids or cyclophosphamide showed a significant reduction in CCN2 levels. This was confirmed by the results of multivariate analysis. Patients with active ocular disease had a significant increase in CCN2 compared to the inactive group. On the other hand, CCN2 levels were not significantly correlated with overall disease activity and severity scores.

CONCLUSION

Behçet's disease patients showed a significant increase of CCN2 levels, especially in the group of patients with major organ involvement. A significant reduction of these levels was found in patients who received steroids or cyclophosphamide. Larger studies with further investigations of the precise role of CCN2 in BD pathogenesis might lead to novel therapies for the clinical management of this disease.

CD28 null CD4 T-cell expansions in autoimmune disease suggest a link with cytomegalovirus infection

Immunosenescence is thought to contribute to the increase of autoimmune diseases in older people. Immunosenescence is often associated with the presence of an expanded population of CD4 T cells lacking expression of CD28 (CD28 ^null). These highly cytotoxic CD4 T cells were isolated from disease-affected tissues in patients with rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, or other chronic inflammatory diseases and their numbers appeared to be linked to disease severity. However, we recently demonstrated that the common herpes virus, cytomegalovirus (CMV), not ageing, is the major driver of this subset of cytotoxic T cells. In this review, we discuss how CMV might potentiate and exacerbate autoimmune disease through the expansion of CD28 ^null CD4 T cells.

Role of ADAMTS-12 in Protecting Against Inflammatory Arthritis in Mice By Interacting With and Inactivating Proinflammatory Connective Tissue Growth Factor

OBJECTIVE

It has been reported that ADAMTS-12 is a susceptibility gene for rheumatoid arthritis (RA) development, and its level is significantly increased in RA patients. In addition, ADAMTS-12 is reported to be required for inflammation in otherwise healthy subjects. This study was undertaken to determine the role of ADAMTS-12 and the underlying mechanisms in the pathogenesis of inflammatory arthritis.

METHODS

The collagen-induced arthritis (CIA) model was established in ADAMTS-12-deficient mice and their control littermates to determine the role of ADAMTS-12 in vivo. Micro-computed tomography scanning was used to demonstrate the destruction of the ankle joint; histologic analysis illustrated synovitis, pannus formation, and bone and cartilage destruction; enzyme-linked immunosorbent assay was performed to measure serum levels of inflammatory cytokines; and protein-protein interaction assays were performed to detect the interactions of ADAMTS-12 and its various deletion mutants with connective tissue growth factor (CTGF).

RESULTS

Deficiency of ADAMTS-12 led to accelerated inflammatory arthritis in the CIA mouse model. Loss of ADAMTS-12 caused enhanced osteoclastogenesis. In vitro and in vivo protein-protein interaction assays demonstrated that ADAMTS-12 bound and processed CTGF, a previously unrecognized substrate of ADAMTS-12. In addition, deletion of ADAMTS-12 enhanced, while overexpression of ADMATS-12 reduced, CTGF-mediated inflammation. Furthermore, ADAMTS-12 regulation of inflammation was largely lost in CTGF-deficient macrophages. Importantly, blocking of CTGF attenuated elevated inflammatory arthritis seen in the ADAMTS-12-deficient CIA mouse model.

CONCLUSION

This study provides evidence that ADAMTS-12 is a critical regulator of inflammatory arthritis and that this is mediated, at least in part, through control of CTGF turnover.

Level of inflammatory cytokines in rheumatoid arthritis patients: Correlation with 25-hydroxy vitamin D and reactive oxygen species

Background

Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder. Reactive oxygen species (ROS) and pro-inflammatory cytokines have been believed to be involved in the etiopathogenesis of the disease. The aim of the study was to determine the correlation of inflammatory cytokines with 25-hydroxy vitamin D and ROS.

Methods

100 RA patients and 50 healthy age and sex matched individuals were included in the study. Patients were further divided on the basis of presence or absence of rheumatoid factor and disease severity. Serum 25-hydroxy vitamin D levels were monitored by chemiluminescent immunoassay. 10% hematocrit was used to detect the level of ROS by spectro fluorometer. The levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-10 and IL-17) were determined in plasma by ELISA.

Results

The level of 25-hydroxy vitamin D was found to be decreased in RA patients in comparison to the control group. However the level of ROS and inflammatory cytokines were found to be elevated in RA patients in comparison with the healthy controls, with the increase being more pronounced in seropositive and RA patients having high disease severity. Inflammatory cytokines showed negative correlation with 25-hydroxy vitamin D and positive correlation with ROS.

Conclusion

This study for the first time shows the association of inflammatory cytokines with 25-hydroxy vitamin D and ROS in RA patients. The results suggest that 25-hydroxy vitamin D being an immune modulator is decreased in the serum of RA patients. Further ROS and cytokines play an important role in the pathogenesis of RA and are responsible for increasing the severity of disease.

Inhibition of each module of connective tissue growth factor as a potential therapeutic target for rheumatoid arthritis

We previously reported the importance of connective tissue growth factor (CTGF) in rheumatoid arthritis (RA). CTGF contains four distinct modules connected in tandem, namely insulin-like growth factor-binding protein (IGFBP)-like, von Willebrand factor (vWF) type C repeat, thrombospondin type 1 (TSP-1) repeat, and carboxyl-terminal (CT) modules. The relationships between each of these modules of CTGF and RA remain unknown. Here, we analyzed how inhibition of each CTGF module affects the pathophysiology of RA. We conducted stimulation and suppression experiments on synovial cells (MH7A) obtained from patients with RA. Moreover, we examined angiogenesis by means of a tube-formation assay performed using human umbilical vein endothelial cells (HUVECs), and we used tartrate-resistant acid phosphatase (TRAP) staining to analyze osteoclastogenesis. Our results showed that M-CSF/RANKL-mediated osteoclastogenesis was enhanced when CTGF was added, but the effect of CTGF was neutralized by mAbs against CTGF modules 1-4. Furthermore, CTGF treatment of HUVECs induced formation of tubular networks, which resulted in acceleration of the angiogenesis of RA synoviocytes, and quantification showed that this tubular-network formation was also disrupted by anti-CTGF module 1-4 mAbs. Lastly, TNF-α enhanced the expression of CTGF and matrix metalloproteinase-3 (MMP3) in MH7A cells, and this enhancement was potently neutralized by mAbs against CTGF modules 1, 3 and 4. Thus, our results indicate that not only a mAb against CTGF but also mAbs against each specific module of CTGF might serve as potential therapeutic agents in the treatment of RA.

The role of cytokines in the pathogenesis of rheumatoid arthritis--Practical and potential application of cytokines as biomarkers and targets of personalized therapy

Rheumatoid arthritis (RA), as a common chronic disease leading to severe disability, requires early diagnosis and introduction of proper treatment. Deregulation in the cytokine network plays an undoubtedly crucial role in the pathogenesis of RA. The understanding of the role of cytokines in RA can be used for patients' benefit. Technological advances had already allowed introduction of the tailor-made cytokine-targeted therapies (so far anti-TNF, anti-IL-1 and anti-IL-6) into clinical practice. This type of treatment is currently developing very fast. Moreover, cytokines are considered to be potential powerful biomarkers of RA with roles predicted to grow in the future. Detailed understanding of the cytokine balance in RA may assist both the diagnostic process and therapy.