The anti-inflammatory action of methotrexate is not mediated by lymphocyte apoptosis, but by the suppression of activation and adhesion molecules

[Low-dose methotrexate: Indications and side effects, particularly in cases of diffuse interstitial pneumonia]

INTRODUCTION

Methotrexate (MTX) is a folate antagonist used as an immunosuppressant in a number of conditions, including rheumatoid arthritis (RA). Low-dose MTX (MTX-LD) is associated with a risk of haematological, hepatic, gastrointestinal and pulmonary toxicity, which may up until now have limited its use.

STATE OF THE ART

In RA, data from retrospective cohorts have reported a possible excess risk of methotrexate toxicity in cases of underlying interstitial lung disease (ILD). However, recent prospective and retrospective multicentre studies have found no such increased risk, and have reassuringly concluded that MTX-LD can be prescribed in cases of RA-associated ILD (RA-ILD).

PERSPECTIVES AND CONCLUSIONS

Current recommendations are not to delay the introduction of MTX in patients with RA at risk of developing ILD or in the presence of RA-ILD with mild to moderate respiratory impairment.

Unlocking the role of the B7-H4 polymorphism in psoriasis: Insights into methotrexate treatment outcomes: A prospective cohort study

B7-H4 is a recently discovered member of B7 family that negatively regulates T-cell immunity, specifically Th1 and Th17 cell responses. However, its role in the pathogenesis of psoriasis has yet to be determined. This study aims to investigate the effect of B7-H4 polymorphism on the efficacy of methotrexate (MTX) and its mechanism in psoriasis. Four single nucleotide polymorphisms of B7-H4 were genotyped in 310 psoriatic patients who received 12-week MTX. The protein expression of B7-H4 in platelets was characterized using immunofluorescence staining, confocal laser scanning microscopy, and flow cytometry techniques. We found that GG genotype carriers of B7-H4 rs1935780 had a lower Psoriasis Area and Severity Index (PASI) 75 response rate and higher weight (p = 0.0245) and body mass index (p = 0.0185) than AA and AG genotype carriers. Multiple regression analysis showed that the PASI score at baseline (p = 0.01) and age at disease onset (p = 0.003) were positively correlated with PASI 75 response rate, while weight (p = 0.005) and the rs1935780 genotype (p = 0.003) were negatively associated with PASI 75 response rate. B7-H4 was expressed in the platelet plasma membrane and cytoplasm. Furthermore, the expression of B7-H4 protein in platelets was lower in good responders than in non-responders and was upregulated considerably after 12-week MTX or in vitro MTX stimulation in good responders. Collectively, these results demonstrate that psoriatic patients with GG genotype of B7-H4 rs1935780 had a poorer response to MTX. Low expression of B7-H4 protein in platelets correlated with better clinical outcomes of MTX in psoriasis.

Mini-dose methotrexate combined with methylprednisolone as a first-line treatment for acute graft-versus-host disease: A phase 2 trial

Background and Objectives

Acute graft-versus-host disease (aGvHD) remains a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methylprednisolone (MP; 1-2 mg/kg/day) remains the standard first-line therapy for aGvHD, although no response is detected in nearly one-half of the patients with aGvHD. This study aimed to investigate the feasibility of mini-dose methotrexate (MTX) combined with standard-dose MP as a front-line therapy for aGvHD.

Materials and Methods

A prospective Phase 2 clinical trial was performed to evaluate the safety and efficacy of 5 mg/m2 MTX combined with 1 mg/kg/day MP as the initial therapy in 31 patients with aGvHD. Moreover, the effects of MTX combined with MP were explored in a humanized xenogeneic murine model of aGvHD.

Results

The overall response and complete response rate at 7 days after the initial treatment were 100% and 83%, respectively. The overall response rate on day 28 was 87%. The complete response rates for aGvHD grades I, II, and III were 100% (6/6), 82% (18/22), and 66% (2/3), respectively. Grade 3 toxicities occurred in only three patients presenting with cytopenia. Importantly, MTX and MP demonstrated synergistic effects on ameliorating aGvHD in humanized xenogeneic murine model.

Conclusion

The current study suggests that mini-dose MTX combined with standard-dose MP could potentially become a novel first-line therapy for patients with aGvHD.

Impact of methotrexate treatment on vaccines immunogenicity in adult rheumatological patients - Lessons learned from the COVID-19 pandemic

Despite the development of new biological and synthetic targeted therapies, methotrexate remains one of the most commonly used immunomodulatory drugs in rheumatology. However, its effect on the immunogenicity of vaccines has been studied only to a limited extent until recently, resulting in the lack of clear guidelines on the use of methotrexate during vaccination. Significant progress was made during the COVID-19 pandemic due to the dynamic development of research on vaccines, including patients with autoimmune inflammatory rheumatic diseases. In the following literature review, we present a summary of what we know so far on the impact of methotrexate on post-vaccination response in adult rheumatology patients, taking into account the lessons learned from the COVID-19 pandemic. Studies on the effect of methotrexate on the immunogenicity of influenza, pneumococcal, herpes zoster, tetanus/diphtheria/pertussis, hepatitis A, yellow fever, and COVID-19 vaccines are described in detail, including the effect of methotrexate on the humoral and cellular response of individual vaccines. The available evidence for recommendations for withholding methotrexate in the post-vaccination period is presented. Lastly, an overview of potential immunological mechanisms through which MTX modulates the immunogenicity of vaccinations is also provided.

Magnetic resonance imaging of methotrexate-related lymphoproliferative disorder with a chief complaint of oral symptoms

OBJECTIVES

To determine the magnetic resonance imaging (MRI) features of methotrexate-related lymphoproliferative disorder (MTX-LPD) in the oral cavity of a patient with a chief complaint of oral symptoms.

METHODS

We included six patients who visited our hospital between November 2014 and November 2019, histopathologically diagnosed with MTX-LPD. All images were examined using 3 T MRI and reviewed by two radiologists.

RESULTS

Masses were detected in five cases; all masses demonstrated signal hypointensity and homogeneous signal hyperintensity on T1- and T2-weighted images with fat suppression. Homogeneous enhancement with fat suppression was evident on post-contrast T1-weighted imaging. We performed dynamic contrast-enhanced MRI in three cases and observed early enhancement with a low washout ratio pattern in all cases. Four patients underwent diffusion-weighted MRI and revealed low mean apparent diffusion coefficient (ADC) of 0.57 (range 0.5-0.65) × 10^-3 mm²/s.

CONCLUSIONS

We reported on the imaging characteristics of six rare cases of MTX-LPD in the oral cavity. Homogeneous hyperintensity on fat-suppressed T2-weighted images and low ADC values are possible features of MTX-LPD. Moreover, MTX-LPD can be differentiated from other carcinomas in the oral cavity.

Fatal low-dose methotrexate toxicity: A case report and literature review

Methotrexate (MTX) is a chemotherapeutic agent that acts primarily by inhibiting the folic acid cycle. In addition to its application for treating malignancies, MTX is also used to treat chronic inflammatory diseases including psoriasis. Adverse effects have been reported even at low doses (up to 25 mg/week), and there is risk of toxicity in the form of myelosuppression, hepatotoxicity, or pulmonary fibrosis. Here, we report a case of a 67-year-old male with a past medical history of end stage renal disease on peritoneal dialysis and moderate-to-severe psoriasis with psoriatic arthritis presented with abdominal pain, diarrhea, rash, mucositis, and mucocutaneous ulcers and erosions. The patient was taking methotrexate 10 mg weekly without folic acid supplementation and was found to be pancytopenic. Despite treatment, the patient developed multiorgan failure and passed away after 16 days of hospitalization. Myelosuppression is considered the most serious side effect with the highest risk of mortality. Risk factors for toxicity include renal insufficiency, advanced age, lack of folate supplementation, drug interactions, and medication errors. Importantly, serum levels of MTX do not correlate with toxicity; therefore, folinic acid rescue therapy should be started as soon as MTX toxicity is suspected. MTX toxicity is rare with low dose, proper dose scheduling, and adherence to the recommended guidelines. It is imperative that physicians considering therapy with low dose MTX for dermatologic indications take into consideration a patient's risk factors for toxicity and monitor appropriately.

Methotrexate Inhibits T Cell Proliferation but Not Inflammatory Cytokine Expression to Modulate Immunity in People Living With HIV

Inflammation associated with increased risk of comorbidities persists in people living with HIV (PWH) on combination antiretroviral therapy (ART). A recent placebo-controlled trial of low-dose methotrexate (MTX) in PWH found that numbers of total CD4 and CD8 T cells decreased in the low-dose MTX arm. In this report we analyzed T cell phenotypes and additional plasma inflammatory indices in samples from the trial. We found that cycling (Ki67+) T cells lacking Bcl-2 were reduced by MTX but plasma inflammatory cytokines were largely unaffected. In a series of in vitro experiments to further investigate the mechanisms of MTX activity, we found that MTX did not inhibit effector cytokine production but inhibited T cell proliferation downstream of mTOR activation, mitochondrial function, and cell cycle entry. This inhibitory effect was reversible with folinic acid, suggesting low-dose MTX exerts anti-inflammatory effects in vivo in PWH largely by blocking T cell proliferation via dihydrofolate reductase inhibition, yet daily administration of folic acid did not rescue this effect in trial participants. Our findings identify the main mechanism of action of this widely used anti-inflammatory medicine in PWH and may provide insight into how MTX works in the setting of other inflammatory conditions.

Drug delivery to the intestinal lymph by oral formulations

Oral drug delivery systems (DDS) targeting lymphocytes in intestinal lymphatic vessels, ducts, and nodes are useful for treating diverse diseases. The intestinal lymph harbors numerous lymphocyte subsets, and DDS containing lipids such as triglycerides and fatty acids can deliver drugs to the lymph through the chylomicron pathway. DDS are efficient, thus allowing the administration of reduced drug doses, which mitigate systemic adverse effects. Here we review orally administered lipid formulations comprising oil solutions, suspensions, micro/nanoemulsions, self-micro/nano emulsifying DDS, liposomes, micelles, solid lipid nanoparticles, and nanostructured lipid carriers for targeting drugs to the lymph. We first describe the structures of lymphatic vessels and lymph nodes and the oral absorption of lipids and drugs into the intestinal lymph. We next summarize the effects of the properties and amounts of lipids and drugs delivered into the lymph and lymphocytes, as well as their effects on drug delivery ratios of lymph to blood. Finally, we describe lymphatic DDS containing saquinavir, tacrolimus, and methotrexate, and their potency that reduce drug concentrations in blood, which are associated with systemic adverse effects.

Methotrexate as a safe immunosuppressive agent during the COVID-19 pandemic

Background

During the ongoing COVID-19 pandemic, immunocompromised patients are at a higher risk of severe infection, since the immune system has an important role in defeating this disease. This study compares the severity of COVID-19 in patients taking methotrexate with the severity of their family members’ illness as patients with normal immune system function.

Methods

A total of 35 participants, including 14 patients taking methotrexate and 21 patients with normal immune function, entered this study, and the indicators of COVID-19 severity were compared between these two groups.

Results

The case group, who were on methotrexate therapy, had significantly less severe COVID-19 based on their symptoms, including fever (p = 0.000) and cough and dyspnea (p = 0.01) as well as in terms of COVID-19 severity indicators such as pulmonary involvement (p = 0.001), ferritin level (p = 0.001), white blood cell count (p = 0.008) and CRP level (p = 0.006), compared to the control group. There was a significant correlation between taking methotrexate and lower severity in COVID-19 disease.

Conclusion

The present findings demonstrated that methotrexate does not predispose patients to severe COVID-19; on the contrary, patients taking methotrexate may experience a milder disease, possibly due to their reduced severe inflammatory reactions as a result of inhibited TNFα, lowered IL6, and increased T regulatory cells. According to these findings, methotrexate appears to be a suitable treatment option for patients who need immunosuppressive medications during the COVID-19 pandemic.

T-Cell Adhesion in Healthy and Inflamed Skin

The diverse populations of tissue-resident and transitory T cells present in the skin share a common functional need to enter, traverse, and interact with their environment. These processes are largely dependent on the regulated expression of adhesion molecules, such as selectins and integrins, which mediate bidirectional interactions between immune cells and skin stroma. Dysregulation and engagement of adhesion pathways contribute to ectopic T-cell activity in tissues, leading to the initiation and/or exacerbation of chronic inflammation. In this paper, we review how the molecular interactions supported by adhesion pathways contribute to T-cell dynamics and function in the skin. A comprehensive understanding of the molecular mechanisms underpinning T-cell adhesion in inflammatory skin disorders will facilitate the development of novel tissue-specific therapeutic strategies.

Cardiovascular effects of approved drugs for rheumatoid arthritis

The risk of cardiovascular disease is increased in patients with rheumatoid arthritis compared with the general population owing to the influence of traditional and non-traditional risk factors. Inflammation has a pivotal contribution and can accelerate the atherosclerotic process. Although dampening inflammation with DMARDs should theoretically abrogate this process, evidence suggests that these drugs can also promote atherosclerosis directly and indirectly, hence adding to an increased cardiovascular burden. However, the extent and direction of the effects largely differ across drugs. Understanding how these drugs influence endothelial damage and vascular repair mechanisms is key to understanding these outcomes. NSAIDs and glucocorticoids can increase the cardiovascular risk. Conversely, conventional, biologic and targeted DMARDs control inflammation and reduce this risk, although some of these drugs can also aggravate traditional factors or thrombotic events. Given these data, the fundamental objective for clinicians should be disease control, in an individualized approach that considers the most appropriate drug for each patient, taking into account joint and cardiovascular outcomes. This Review provides a comprehensive analysis of the effects of DMARDs and other approved drugs on cardiovascular involvement in rheumatoid arthritis, from a clinical and mechanistic perspective, with a roadmap to inform the research agenda.

[Recommendations when switching therapy from immunosuppressive drugs to dupilumab in patients with atopic dermatitis]

Based on new insights into the molecular pathogenesis of atopic dermatitis, a targeted anti-inflammatory therapy-dupilumab-has recently been approved as treatment alongside glucocorticoids and ciclosporin. Due to their pharmacology, neither glucocorticoids nor ciclosporin nor the off label used substances methotrexate, azathioprine and mycophenolic acid derivatives are suitable for long-term therapy. When switching therapy from small molecular substances to dupilumab, various factors should be considered. Both the specific cause of the change (ineffectiveness, adverse effects or contraindications) as well as the pharmacological conditions should be taken into account. Since there have been no specific clinical studies on this subject so far, the authors relied mainly on a literature search to draw up recommendations for practical everyday use.

Vascular endothelial growth factor-A as a promising therapeutic target for the management of psoriasis

Vascular endothelial growth factor-A (VEGF-A), the main angiogenic mediator, plays a critical role in the pathogenesis of several inflammatory immune-mediated diseases, including psoriasis. Even though anti-angiogenic therapies, such as VEGF inhibitors, are licensed for the treatment of various cancers and eye disease, VEGF-targeting interventions are not part of current psoriasis therapy. In this viewpoint essay, we argue that the existing preclinical research evidence on the role of VEGF-A in the pathogenesis of psoriasis as well as clinical observations in patients who have experienced psoriasis remission during oncological anti-VEGF-A therapy strongly suggests to systematically explore angiogenesis targeting also in the management of psoriasis. We also point out that some psoriasis therapies decrease circulating levels of VEGF-A and normalise the psoriasis-associated vascular pathology in the papillary dermis of plaques of psoriasis and that a subset of patients with constitutionally high levels of VEGF-A may benefit most from the anti-angiogenic therapy we advocate here. Given that novel, well-targeted personalised medicine therapies for the development of psoriasis need to be developed, we explore the hypothesis that VEGF-A and signalling through its receptors constitute a promising target for therapeutic intervention in the future management of psoriasis.

A Rationally Designed Micellar Nanocarrier for the Delivery of Hydrophilic Methotrexate in Psoriasis Treatment

Methotrexate (MTX) is broadly applied in the clinic for the treatments of cancers and autoimmune diseases. Targeted delivery of MTX is attractive to improve its efficacy and reduce off-target toxicity. However, MTX encapsulation in nanoparticle is challenging due to its high water solubility. We rationally designed a well-defined telodendrimer (TD) nanocarrier based on MTX structure to sequester it in nanoparticles. Riboflavin (Rf) and positive charges groups were precisely conjugated on TD to form multivalent hydrogen bonds, π-π stacking and electrostatic interactions with MTX. A reverse micelle approach was developed to preset MTX and TD interactions in the core of micelles, which ensures the effective MTX loading upon dispersion into aqueous solution. As results, MTX loading capacity reaches over 20% (w/w) in the optimized nanocarrier with the particle size of 20-30 nm. The nanoformulations sustain the release of MTX in a controlled manner and exhibit excellent hemocompatibility. The in vitro cellular uptake of MTX was significantly improved by the nanoformulations. The potency of MTX nanoformulations is comparable to the free MTX in cytotoxicity. A psoriasis-like skin inflammation model was induced in mouse by imiquimod (IMQ) stimulation. MTX nanoformulations improved the psoriasis targeting and exhibited a superior long-lasting efficacy in reducing skin inflammation compared with the free MTX in psoriasis treatment.

Cutaneous lupus erythematosus: The impact of self-amplifying innate and adaptive immune responses and future prospects of targeted therapies

Cutaneous lupus erythematosus (CLE) is a heterogeneous autoimmune disease encompassing a broad spectrum of skin conditions including localized plaques or widespread lesions, which may be accompanied by systemic involvement (systemic lupus erythematosus (SLE)). The disease is characterized by necroptotic keratinocytes and a cytotoxic immune cell infiltrate at the dermo-epidermal junction (DEJ), orchestrated by interferon (IFN)-regulated proinflammatory cytokines. Molecular analyses revealed a strong upregulation of innate and adaptive immune pathways in lesional skin including DNA-recognition pathways, chemokine signalling, antigen presentation and B- and T-cell activation, which are believed to interact in a complex self-amplifying network. Concerning adaptive immune signalling, particularly B cells are currently being studied as there is growing evidence for additional abilities besides autoantibody expression in skin autoimmunity. These detailed insights have paved the way for the development of drugs targeting crucial molecules of pathogenic immune cells and pathways. Moreover, they forwarded the understanding of distinct molecular mechanisms within CLE subtypes, which might enable a more mechanism-directed, stratified pharmacotherapy of LE skin lesions in the future.

Immune response in LPD during methotrexate administration (MTX-LPD) in rheumatoid arthritis patients

Methotrexate (MTX) is known as a first-line synthetic disease-modifying anti-rheumatic drug (DMARD) for the treatment of rheumatoid arthritis (RA). Although the risk of LPD development increases by RA inflammation itself, observation of spontaneous regression of LPD after MTX discontinuation lead to the theory of lymphomagenic role of MTX. In this review, we focused on the several immune response involved in LPD that developed under MTX administration in RA patients.

Treatment Modalities of Psoriasis: A Focus on Requisite for Topical Nanocarrier

BACKGROUND AND OBJECTIVE

Psoriasis is an autoimmune skin disease involving cascading release of cytokines activated by the innate and acquired immune system. The increasing prevalence rate of psoriasis demands for more appropriate therapy. The existing chemical moiety is promising for better therapeutic outcome, but the selection of a proper channel for administration has to be reviewed. Hence there is a need to select the most appropriate dosage form and route of administration for improving the curative rate of psoriasis.

RESULTS

A total of 108 systematic reviews of research and review articles were conducted to make the manuscript comprehensible. The role of inflammatory mediators in the pathogenesis of the disease is discussed for a better understanding of the selection of pharmacotherapy. The older and newer therapeutic moiety with its mode of administration for psoriasis treatment has been discussed. With a comparative review on topical and oral administration of first-line drugs such as methotrexate (MTX), cyclosporine (CsA), and betamethasone, its benefits-liabilities in the selected routes were accounted for. Emphasis has also been paid on advanced nanocarriers for dermatologic applications.

CONCLUSION

For a better therapeutic outcome, proper selection of drug moiety with its appropriate administration is the major requisite. With the advent of nanotechnology, the development of nanocarrier for dermatologic application has been successfully demonstrated in positioning the systemically administrated drug into topical targeted delivery. In a nutshell, to achieve successful treatment strategies towards psoriasis, there is a need to focus on the development of stable, non-toxic nanocarrier for topical delivery. Inclusion of the existing orally administered drug moiety into nanocarriers for topical delivery is proposed in order to enhance therapeutics payload with reduced side effects which serves as a better treatment approach for relief of the psoriasis condition.

Declining levels of serum chemokine (C-X-C motif) ligand 10 over time are associated with new onset of psoriatic arthritis in patients with psoriasis: a new biomarker?

BACKGROUND

We previously found that serum levels of chemokine (C-X-C motif) ligand 10 (CXCL10) decreased after the onset of psoriatic arthritis (PsA).

OBJECTIVES

We measured CXCL10 levels over time in patients with psoriasis who developed PsA to determine whether the drop in CXCL10 was specific to these patients and further assess its association with PsA development.

METHODS

Prospectively followed patients with psoriasis without arthritis [cutaneous psoriasis (PsC)] were assessed yearly by rheumatologists for the presence of PsA. Patients with PsC who developed PsA (converters) were matched to those that did not develop PsA (nonconverters) based on psoriasis duration and the interval between follow-up visits. The duration between baseline and the first visit postconversion in converters was used to assign a pseudoconversion date in nonconverters. Linear mixed-effects models were used to model the expression of CXCL10 over time.

RESULTS

CXCL10 significantly declined over time in converters prior to PsA development with a significant difference in the trend over time between converters (n = 29) and nonconverters (n = 52; P < 0·001). CXCL10 continued to decline after PsA onset in a subset of converters. There was a significant difference in the trend of CXCL10 levels between converters (n = 24) and nonconverters (n = 16; P = 0·01) preconversion/pseudoconversion. This difference remained postconversion (P = 0·006) and was not different from the preconversion period (P = 0·75).

CONCLUSIONS

A large difference in CXCL10 was identified in patients with PsC that are destined to develop PsA over time. This exploratory analysis supports the association of CXCL10 with PsA development in patients with PsC and warrants further study of the predictive ability of this chemokine. What is already known about this topic? Chemokine (C-X-C motif) ligand 10 (CXCL10) is elevated in psoriatic affected tissues and serum and/or plasma. Patients with psoriasis that develop psoriatic arthritis (PsA) have elevated CXCL10 levels at baseline and these levels drop after arthritis onset. What does this study add? By monitoring levels of CXCL10 in serum over multiple visits in patients with psoriasis that develop PsA as well as those that do not develop PsA, an association was identified between CXCL10 and PsA development. What is the translational message? CXCL10 is a strong candidate for use by physicians for the detection of patients with psoriasis that are at risk of developing PsA. Linked Comment: Kirby and Fitzgerald. Br J Dermatol 2020; 183:805-806.

Haploidentical stem cell transplant with post-transplantation cyclophosphamide and mini-dose methotrexate in children

BACKGROUND

Haploidentical stem cell transplantation (haplo-SCT) is an option for patients without human leukocyte antigen-matched related or unrelated donor. Post-transplantation cyclophosphamide (PTCy) is an effective method of graft versus host disease (GVHD) prophylaxis and permits the use of T-cell replete grafts in settings were ex vivo manipulation is not feasible.

METHODS

A retrospective study among patients younger than 18 years, with a history of hematologic malignancies who underwent haplo-SCT between 2012 and 2016. All patients received a preparative regimen of fludarabine, busulfan, and 400 cGy total body irradiation or melphalan. Post-transplant GvHD prophylaxis consisted either of PTCy (50 mg/kg on Days + 3 and + 4) and cyclosporine (CSA) plus mycophenolate (MMF) (15 mg/kg/dose, thrice daily, per os), or mini-dose methotrexate (MTX; 5 mg/m² dose) on Days + 5, +7, +10, and + 15.

RESULTS

A total of 52 children were included, whose median age was 9 years (interquartile range, 4.9-14; range, 1.2-17 years), and 63% were males. The most common complications were cytomegalovirus reactivation (57%) and hemorrhagic cystitis (36%). The acute GVHD prophylaxis was PTCy, CSA, and mini-dose MTX in 42 (81%) patients, and 10 (19%) patients received PTCy, CSA, and MMF. The cumulative incidence of acute GvHD II-IV, acute GvHD III-IV, and chronic GvHD were 42%, 8.5%, and 19%, respectively. Grades I-IV acute GvHD occurred in 100% of the patients who received prophylaxis with CSA and MMF, and 62% who received CSA and mini-dose MTX (p = .055). The transplant-related mortality at 100 days was 18%. The 5-year overall and event-free survival were 59% and 57%, respectively.

CONCLUSIONS

Haplo-SCT with PT/Cy can be an available, safe, and feasible option for children with hematologic malignancies; meanwhile, the use of mini-dose of MTX was associated with lower rates of acute GVHD. However, our results require further support from prospective randomized studies to improve the efficacy of this prophylactic strategy.

Mécanisme d'action du méthotrexate dans le traitement de la polyarthrite rhumatoïde

Le méthotrexate est utilisé dans le traitement de la polyarthrite rhumatoïde (PR) depuis les années 1980 et est souvent à ce jour le médicament de première intention pour le traitement de la PR. Dans cette revue, nous examinons plusieurs hypothèses pour expliquer le mécanisme à l'origine de l'efficacité du méthotrexate dans la PR. Celles-ci comprennent l'antagonisme du folate, la signalisation par l'adénosine, la génération d'espèces réactives de l'oxygène (ROS), la diminution des molécules d'adhérence, la modification des profils cytokiniques et l'inhibition des polyamines, entre autres. Actuellement, la signalisation par l'adénosine est probablement l'explication la plus largement acceptée du mécanisme du méthotrexate dans la PR, car le méthotrexate augmente les taux d'adénosine et suite à l'engagement de l'adénosine avec ses récepteurs extracellulaires, une cascade intracellulaire est activée et favorise un état antiinflammatoire global. Outre ces hypothèses, nous examinons le mécanisme du méthotrexate dans la PR sous l'angle de ses effets indésirables et considérons certains des nouveaux marqueurs génétiques de l'efficacité et de la toxicité du méthotrexate dans la PR. Enfin, nous discutons brièvement du mécanisme du méthotrexate en association avec un traitement de la PR par un inhibiteur du TNF-. En fin de compte, en trouvant une explication claire de la voie et du mécanisme conduisant à l'efficacité du méthotrexate dans la PR, il pourrait exister un moyen de formuler des thérapies plus puissantes avec moins d'effets secondaires.

Comparative Study of Tacrolimus and Short-Term Methotrexate: 2-Day versus 3-Day Methotrexate as Graft-versus-Host-Disease Prophylaxis after Umbilical Cord Blood Transplantation in Adults

Methotrexate (MTX) in combination with a calcineurin inhibitor has been commonly used for prophylaxis of graft-versus-host disease (GVHD) following umbilical cord blood transplantation (UCBT) in Japan. However, the appropriate prophylactic MTX dosage in UCBT has not been established to date. To determine the preferential GVHD prophylaxis in UCBT, this study retrospectively investigated the administration of short-term MTX for 2 days versus 3 days. Of 103 adult patients submitted to UCBT enrolled in the study, 73 received tacrolimus (TAC) with 2 days of MTX given at 10 mg/m² on day 1 and 7 mg/m² on day 3 (very short-term [vs] MTX), whereas 30 patients received TAC with 3 days of MTX given at 10 mg/m² on day 1, 7 mg/m² on day 3, and 7 mg/m² on day 6 (short-term [s] MTX). In univariate analysis, neutrophil engraftment was shown to be significantly better (P = .039) in the vsMTX/TAC group. Among high-risk patients, the vsMTX/TAC group also exhibited earlier neutrophil engraftment (P = .042); however, the incidence of acute GVHD was higher in the vsMTX/TAC group (P = .035) on univariate analysis. In multivariate analysis, compared with sMTX/TAC, vsMTX/TAC was associated with lower risk of relapse (hazard ratio, .27; 95% confidence interval, .11 to .64; P = .003) . These results suggest that vsMTX/TAC can be appropriate GVHD prophylaxis after UCBT, especially in higher-risk patients.

Relevance of the antioxidant properties of methotrexate and doxycycline to their treatment of cardiovascular disease

Many medications exhibit clinical benefits that are unrelated to their primary therapeutic uses. In many cases, the mechanisms underpinning these pleotropic effects are unknown. Two commonly prescribed medications that exhibit pleotropic benefits in cardiovascular disease and other diseases associated with chronic inflammation are methotrexate (MTX) and doxycycline (DOX). The vast majority of cardiovascular disease is associated with atherosclerosis. Because atherosclerosis is a chronic inflammatory disease, possible mechanisms by which MTX and DOX reduce inflammation have been investigated. Interestingly, the primary structure of both of these medications contain aromatic phenolic rings, which resemble polyphenols that are known to possess antioxidant activity. Inflammation and oxidative stress are intimately related. Inflammation promotes oxidative stress, which in turn leads to further inflammation; in this way, oxidative stress and inflammation can establish a self-perpetuating cycle. It has been shown that MTX and DOX act as antioxidants and are capable of scavenging free radicals and the reactive oxygen species (ROS) superoxide (O₂^-). Furthermore, both MTX and DOX inhibit the formation of malondialdehyde acetaldehyde (MAA) adducts, products of oxidative stress and lipid peroxidation. Importantly, MAA-adducts are highly immunogenic and initiate inflammatory responses; thereby, fueling the cycle of inflammation and oxidative stress that results in chronic inflammation. Thus, reducing the formation of MAA-adducts may ameliorate inflammation that leads to ROS production and in this way, break the self-sustaining cycle of oxidative stress and inflammation. It is possible that the under-recognized antioxidant properties of these medications may be a mechanism by which they and other medications provide pleotropic benefit in the treatment of chronic inflammatory disease.

Early and Accurate Prediction of Clinical Response to Methotrexate Treatment in Juvenile Idiopathic Arthritis Using Machine Learning

Background and Aims: Accurately predicting the response to methotrexate (MTX) in juvenile idiopathic arthritis (JIA) patients before administration is the key point to improve the treatment outcome. However, no simple and reliable prediction model has been identified. Here, we aimed to develop and validate predictive models for the MTX response to JIA using machine learning based on electronic medical record (EMR) before and after administering MTX.

Materials and Methods: Data of 362 JIA patients with MTX mono-therapy were retrospectively collected from EMR between January 2008 and October 2018. DAS44/ESR-3 simplified standard was used to evaluate the MTX response. Extreme gradient boosting (XGBoost), support vector machine (SVM), random forest (RF), and logistic regression (LR) algorithms were applied to develop and validate models with 5-fold cross-validation on the randomly split training and test set. Data of 13 patients additionally collected were used for external validation.

Results: The XGBoost screened out the optimal 10 pre-administration features and 6 mix-variables. The XGBoost established the best model based on the 10 pre-administration variables. The performances were accuracy 91.78%, sensitivity 90.70%, specificity 93.33%, AUC 97.00%, respectively. Similarly, the XGBoost developed a better model based on the 6 mix-variables, whose performances were accuracy 94.52%, sensitivity 95.35%, specificity 93.33%, AUC 99.00%, respectively.

Conclusion: Based on common EMR data, we developed two MTX response predictive models with excellent performance in JIA using machine learning. These models can predict the MTX efficacy early and accurately, which provides powerful decision support for doctors to make or adjust therapeutic scheme before or after treatment.

Targeting Adenosine in Cancer Immunotherapy to Enhance T-Cell Function

T cells play a critical role in cancer control, but a range of potent immunosuppressive mechanisms can be upregulated in the tumor microenvironment (TME) to abrogate their activity. While various immunotherapies (IMTs) aiming at re-invigorating the T-cell-mediated anti-tumor response, such as immune checkpoint blockade (ICB), and the adoptive cell transfer (ACT) of natural or gene-engineered ex vivo expanded tumor-specific T cells, have led to unprecedented clinical responses, only a small proportion of cancer patients benefit from these treatments. Important research efforts are thus underway to identify biomarkers of response, as well as to develop personalized combinatorial approaches that can target other inhibitory mechanisms at play in the TME. In recent years, adenosinergic signaling has emerged as a powerful immuno-metabolic checkpoint in tumors. Like several other barriers in the TME, such as the PD-1/PDL-1 axis, CTLA-4, and indoleamine 2,3-dioxygenase (IDO-1), adenosine plays important physiologic roles, but has been co-opted by tumors to promote their growth and impair immunity. Several agents counteracting the adenosine axis have been developed, and pre-clinical studies have demonstrated important anti-tumor activity, alone and in combination with other IMTs including ICB and ACT. Here we review the regulation of adenosine levels and mechanisms by which it promotes tumor growth and broadly suppresses protective immunity, with extra focus on the attenuation of T cell function. Finally, we present an overview of promising pre-clinical and clinical approaches being explored for blocking the adenosine axis for enhanced control of solid tumors.

Repeated Injection of Methotrexate into Silicone Oil-Filled Eyes for Grade C Proliferative Vitreoretinopathy: A Pilot Study

PURPOSE

To evaluate the effects of repeated intra-silicone oil (SO) injections of methotrexate (MTX) on the outcomes of surgery for rhegmatogenous retinal detachment (RRD) with grade C proliferative vitreoretinopathy (PVR-C).

METHODS

In this prospective pilot case series, eyes with RRD and PVR-C underwent pars plana vitrectomy and intraocular injection of SO. At the conclusion of the procedure, 250 µg of MTX was injected into the SO-filled vitreous cavity. Intra-SO injection was repeated at weeks 3 and 6; the minimum follow-up period was 6 months. The main outcome measure was retinal reattachment rate.

RESULTS

Eleven eyes of 11 patients (mean age, 52.73 ± 18.01 years) were included. The mean follow-up period was 9 ± 3 months (range, 6-15 months). Total retinal detachment with anterior and/or posterior PVR-C was present in all eyes before surgery. Mean preoperative best-corrected visual acuity (BCVA) was 2.62 ± 0.04 logMAR. All operated eyes exhibited retinal reattachment posterior to the equator during the follow-up period. Mean postoperative BCVA was significantly improved to 1.02 ± 0.51 logMAR (p = 0.003). No ocular or systemic side effects were observed.

CONCLUSION

Repeated intra-SO injection of MTX as an adjunctive therapy for RRD complicated by PVR showed promising results and was not associated with adverse effects. Further studies are needed to confirm its possible beneficial effects on the final anatomic and functional outcomes in these cases.

Corticosteroids and methotrexate as adjuvants to costimulation blockade in non-human primate renal transplantation

Belatacept, the CD28-B7 costimulation pathway inhibitor, has been approved as a calcineurin inhibitor (CNI) alternative in kidney transplantation. Although costimulation blockade (CoB) allows for CNI avoidance, it is associated with increased rates of early rejection, prompting a search for agents to pair with belatacept. Methotrexate (MTX) is an antimetabolite that has been found to be complimentary with abatacept, a lower affinity CD28-B7-specific analogue of belatacept, in the treatment of rheumatoid arthritis (RA). We examined whether this synergy would extend to prevention of kidney allograft rejection. Rhesus macaques underwent kidney transplantation treated with abatacept maintenance therapy with either a steroid taper, MTX, or both. The combination of abatacept maintenance with steroids prolonged graft survival compared to untreated historical controls and previous reports of abatacept monotherapy. The addition of MTX did not provide additional benefit. These data demonstrate that abatacept with adjuvant therapy may delay the onset of acute rejection, but fail to show synergy between abatacept and MTX beyond that of steroids. These findings indicate that MTX is unlikely to be a suitable adjuvant to CoB in kidney transplantation, but also suggest that with further modification, a CoB regimen used for advanced RA may suffice for RA patients requiring kidney transplantation.

EBV-positive mucocutaneous ulcer arising in rheumatoid arthritis patients treated with methotrexate: Single center series of nine cases

Methotrexate (MTX) is currently used as first-line anchor drug for rheumatoid arthritis (RA). Therefore, the number of MTX-associated lymphoproliferative disorders, including Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU), has increased. Some aspects of MTX-associated EBVMCU (MTX-EBVMCU), particularly clinical behavior and treatment for RA after MTX cessation, have not been well described. Herein, we report nine cases of MTX-EBVMCU with clinical information regarding RA. Seven of nine patients showed spontaneous regression (SR) after immunosuppressive (IS) cessation. The other two required cytotoxic chemotherapy. Eventually, all achieved complete remission. No patients experienced EBVMCU relapse. Eight patients had RA flare after IS cessation. To control the RA activity, rituximab was administered to three patients. The remaining patients were treated by other agents. Regarding the RA activity, all were in the status of low disease activity or clinical remission. In conclusion, MTX-associated EBVMCU has an indolent clinical course and SR after IS cessation can be expected. After the withdrawal of MTX, the majority of patients experience RA flare and required treatment. In our series, RA was well controlled without reinitiating MTX. Therefore, to prevent the EBVMCU relapse, it might be advisable to avoid MTX reintroduction, and rituximab might be the more preferable agent for RA treatment.

Methotrexate mechanism in treatment of rheumatoid arthritis

Methotrexate has been used in treatment of rheumatoid arthritis (RA) since the 1980s and to this day is often the first line medication for RA treatment. In this review, we examine multiple hypotheses to explain the mechanism of methotrexate efficacy in RA. These include folate antagonism, adenosine signaling, generation of reactive oxygen species (ROS), decrease in adhesion molecules, alteration of cytokine profiles, and polyamine inhibition amongst some others. Currently, adenosine signaling is probably the most widely accepted explanation for the methotrexate mechanism in RA given that methotrexate increases adenosine levels and on engagement of adenosine with its extracellular receptors an intracellular cascade is activated promoting an overall anti-inflammatory state. In addition to these hypotheses, we examine the mechanism of methotrexate in RA from the perspective of its adverse effects and consider some of the newer genetic markers of methotrexate efficacy and toxicity in RA. Lastly, we briefly discuss the mechanism of additive methotrexate in the setting of TNF-α inhibitor treatment of RA. Ultimately, finding a clear explanation for the pathway and mechanism leading to methotrexate efficacy in RA, there may be a way to formulate more potent therapies with fewer side effects.

Methotrexate in the Treatment of Moderate to Severe Atopic Dermatitis: A Retrospective Study

Background:

Atopic dermatitis is a common inflammatory condition of the skin. Moderate to severe cases not responding to topical treatments and lifestyle changes may need second-line therapy. Methotrexate has been suggested as an effective treatment in such cases.

Objective:

This study was done to determine the efficacy, adverse effects, and safety profile of methotrexate therapy in patients with atopic dermatitis.

Materials/Methods:

All adult patients with moderate to severe atopic dermatitis seen in the dermatology clinic at this tertiary hospital from January 2015 to December 2015 who were treated with methotrexate were reviewed in a retrospective chart review.

Results:

Forty-one patients (19 female, 22 male, mean age 45 years, range 19-90 years) were enrolled. Of these, 29% were naive to any systemic treatments in the past, including systemic corticosteroids. Methotrexate treatment resulted in excellent improvement (>75%) in 93% of patients, good (50%-75% improvement) in 5%, and partial (25%-50% improvement) in 2%. Median duration of therapy was 26 months, and 80% of patients were still on treatment at last review. Transient nonsignificant elevation of transaminases was the most common adverse effect noted in 20%, followed by nausea in 12% and fatigue in 7%. A fibroscan was done in 10 patients at cumulative doses ranging from 2 to 11 g methotrexate. No liver fibrosis was seen in these patients.

Conclusion:

Methotrexate is an effective treatment for moderate to severe atopic dermatitis with an acceptable safety profile. A low dose can be used to control the disease for prolonged periods without significant risk.

Analysis of Drug Effects on Primary Human Coronary Artery Endothelial Cells Activated by Serum Amyloid A

Background

RA patients have a higher incidence of cardiovascular diseases compared to the general population. Serum amyloid A (SAA) is an acute-phase protein, upregulated in sera of RA patients.

Aim

To determine the effects of medications on SAA-stimulated human coronary artery endothelial cells (HCAEC).

Methods

HCAEC were preincubated for 2 h with medications from sterile ampules (dexamethasone, methotrexate, certolizumab pegol, and etanercept), dissolved in medium (captopril) or DMSO (etoricoxib, rosiglitazone, meloxicam, fluvastatin, and diclofenac). Human recombinant apo-SAA was used to stimulate HCAEC at a final 1000 nM concentration for 24 hours. IL-6, IL-8, sVCAM-1, and PAI-1 were measured by ELISA. The number of viable cells was determined colorimetrically.

Results

SAA-stimulated levels of released IL-6, IL-8, and sVCAM-1 from HCAEC were significantly attenuated by methotrexate, fluvastatin, and etoricoxib. Both certolizumab pegol and etanercept significantly decreased PAI-1 by an average of 43%. Rosiglitazone significantly inhibited sVCAM-1 by 58%.

Conclusion

We observed marked influence of fluvastatin on lowering cytokine production in SAA-activated HCAEC. Methotrexate showed strong beneficial effects for lowering released Il-6, IL-8, and sVCAM-1. Interesting duality was observed for NSAIDs, with meloxicam exhibiting opposite-trend effects from diclofenac and etoricoxib. This represents unique insight into specific responsiveness of inflammatory-driven HCAEC relevant to atherosclerosis.

Therapeutic drug repositioning using personalized proteomics of liquid biopsies

BACKGROUND

In patients with limited response to conventional therapeutics, repositioning of already approved drugs can bring new, more effective options. Current drug repositioning methods, however, frequently rely on retrospective computational analyses and genetic testing - time consuming methods that delay application of repositioned drugs. Here, we show how proteomic analysis of liquid biopsies successfully guided treatment of neovascular inflammatory vitreoretinopathy (NIV), an inherited autoinflammatory disease with otherwise poor clinical outcomes.

METHODS

Vitreous biopsies from NIV patients were profiled by an antibody array for expression of 200 cytokine-signaling proteins. Non-NIV controls were compared with NIV samples from various stages of disease progression. Patterns were identified by 1-way ANOVA, hierarchical clustering, and pathway analysis. Subjects treated with repositioned therapies were followed longitudinally.

RESULTS

Proteomic profiles revealed molecular pathways in NIV pathologies and implicated superior and inferior targets for therapy. Anti-VEGF injections resolved vitreous hemorrhages without the need for vitrectomy surgery. Methotrexate injections reversed inflammatory cell reactions without the side effects of corticosteroids. Anti-IL-6 therapy prevented recurrent fibrosis and retinal detachment where all prior antiinflammatory interventions had failed. The cytokine array also showed that TNF-α levels were normal and that corticosteroid-sensitive pathways were absent in fibrotic NIV, helping explain prior failure of these conventional therapeutic approaches.

CONCLUSIONS

Personalized proteomics can uncover highly personalized therapies for autoinflammatory disease that can be timed with specific pathologic activities. This precision medicine strategy can also help prevent delivery of ineffective drugs. Importantly, proteomic profiling of liquid biopsies offers an endpoint analysis that can directly guide treatment using available drugs.

Methotrexate and anti-tumor necrosis factor treatment improves endothelial function in patients with inflammatory arthritis

Background

Inflammatory arthritis (IA), including rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA), leads to increased cardiovascular disease occurrence probably due to atherosclerosis. One of the first stages in atherogenesis is endothelial dysfunction (ED). Therefore, we aimed to compare endothelial function (EF) in patients with IA, and to examine the effects of methotrexate (MTX) monotherapy and antitumor necrosis factor (anti-TNF) treatment with or without MTX comedication (anti-TNF ± MTX) on EF.

Methods

From the PSARA observational study, all patients with RA (n = 64), PsA (n = 29), and AS (n = 20) were evaluated for EF. In patients with ED at baseline (n = 40), we evaluated changes in the Reactive Hyperemic Index (RHI) after 6 weeks and 6 months of antirheumatic therapy.

Results

In IA patients with ED, RHI significantly improved after 6 weeks (p < 0.001) and 6 months (p < 0.001) of treatment, independent of changes in disease activity parameters. After 6 months, RHI had improved more in the MTX group than in the anti-TNF ± MTX group, and the difference remained statistically significant after adjustments for potential confounders. Among patients with active RA, AS, and PsA, those with AS appeared to have the worst endothelial function, although they were the youngest.

Conclusion

Treatment with MTX and anti-TNF ± MTX was associated with a relatively fast improvement of EF in IA patients with ED, independent of change in disease activity. Therefore, modes of action other than the anti-inflammatory effect may contribute to the EF improvement. After 6 months, the EF improvement was more pronounced in the MTX group than in the anti-TNF ± MTX group.

Trial registration

Clinicaltrials, NCT00902005. Registered on 13 May 2009.

Effect of Methotrexate on an In Vitro Patient-Derived Model of Proliferative Vitreoretinopathy

Purpose

The purpose of this study was to develop a method for isolating, culturing, and characterizing cells from patient-derived membranes in proliferative vitreoretinopathy (PVR) to be used for drug testing.

Methods

PVR membranes were obtained from six patients with grade C PVR. Membrane fragments were analyzed by gross evaluation, fixed for immunohistologic studies to establish cell identity, or digested with collagenase II to obtain single cell suspensions for culture. PVR-derived primary cultures were used to examine the effects of methotrexate (MTX) on proliferation, migration, and cell death.

Results

Gross analysis of PVR membranes showed presence of pigmented cells, indicative of retinal pigment epithelial cells. Immunohistochemistry identified cells expressing α-smooth muscle actin, glial fibrillary acidic protein, Bestrophin-1, and F4/80, suggesting the presence of multiple cell types in PVR. Robust PVR primary cultures (C-PVR) were successfully obtained from human membranes, and these cells retained the expression of cell identity markers in culture. C-PVR cultures formed membranes and band-like structures in culture reminiscent of the human condition. MTX significantly reduced the proliferation and band formation of C-PVR, whereas it had no significant effect on cell migration. MTX also induced regulated cell death within C-PVR as assessed by increased expression of caspase-3/7.

Conclusions

PVR cells obtained from human membranes can be successfully isolated, cultured, and profiled in vitro. Using these primary cultures, we identified MTX as capable of significantly reducing growth and inducing cell death of PVR cells in vitro.

Interaction between saliva's adenosine and tick parasitism: effects on feeding and reproduction

Background

It has recently been demonstrated that saliva from Rhipicephalus sanguineus ticks contains adenosine (ADO) and prostaglandin E2 (PGE2), two non-protein molecules that have significant immunomodulatory properties. These molecules can inhibit cytokine production by dendritic cells (DCs), while also reducing the expression of CD40 in these cells. However, more studies are needed for a better understanding of their participation in the feeding of ticks in vivo. This work, therefore, evaluated the importance of ADO during tick infestations. Mice were infested with adult ticks (3 couples/mouse), and their skin was collected at the tick-infested site (3rd and 7th day), and mRNA for receptors of ADO was quantified by real-time PCR.

Results

Tick infestation increased by four and two times the expression of the A2b and A3v1 receptors on day 3, respectively, while expression of other ADO receptors was unaltered. In addition, we treated mice (n = 10/group) daily with 8-(p-Sulfophenyl)theophylline, 8-pSPT, 20 mg/kg, i.p.), a non-selective antagonist of ADO receptors, and evaluated the performance of ticks during infestations. Female ticks fed on 8-pSPT-treated mice presented a reduction in their engorgement, weight and hatching rates of egg masses, and survival times of larvae compared to the same parameters presented by ticks in the control group. To investigate if these 8-pSPT-treated mice presented altered immune responses, we performed three tick infestations and collected their lymph node cells to determine the percentages and activation state of DCs and cytokine production by lymphocytes by flow cytometry (Cytometric Bead Array technique, CBA). Our data showed that 8-pSPT-treated mice presented an increase in the percentage of DCs as well as of their stimulatory and co-stimulatory molecules (CD40, CD80 and MHCII). Regarding production of T cell cytokines, we observed a significant increase in the levels of IL-2 and a significant decrease in IL-10, IL-17, TNF-α and IFN-γ cytokines.

Conclusions

These results suggest that ADO produced by ticks helps them feed and reproduce and that this effect may be due to modulation of host DCs and T cells.

Pathogenesis and FDG-PET/CT findings of Epstein-Barr virus-related lymphoid neoplasms

Epstein-Barr virus (EBV) is one of the most common viruses, infecting more than 90% of the adult population worldwide. EBV genome is detected in some lymphoid neoplasms. Not only their histopathological subtypes, but also their backgrounds and their clinical courses are variable. A number of B-cell lymphoproliferative disorders associated with the immunocompromised state are related to EBV infection. The incidences of these disorders have been increasing along with generalization of organ transplantations and use of immunosuppressive treatments. Furthermore, some EBV-positive lymphoma can also occur in immunocompetent patients. While evaluating patients with generalized lymphadenopathy of unknown cause by positron emission tomography/computed tomography with 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG-PET/CT), the possibility of lymphoid neoplasms should be considered in some patients, and a careful review of the background and previous history of the patients is necessary. In this review article, we describe the pathogenesis of EBV-related lymphoid neoplasms and then present FDG-PET/CT images of representative diseases. In addition, we also present a review of other EBV-related diseases, such as infectious mononucleosis and nasopharyngeal carcinoma.

Cardiovascular inflammation is reduced with methotrexate in diabetes

Diabetes increases the risk of vascular events and mortality. While earlier type 2 diabetes trials demonstrated that intensive glucose lowering reduces microvascular complications, it is only recently that treatment with some of the newer antihyperglycemic agents has been associated with macrovascular benefits. We report herein that db/db mice concomitantly fed the Western diet and treated with the anti-inflammatory agent methotrexate display a less aggressive inflammatory (lower serum IL-1β, IL-6, SDF-1, and TNFα levels; higher circulating adiponectin, IL-12p70 and IL-10 concentrations; lower aortic VCAM-1 levels) profile than their saline-treated counterpart. Furthermore, acetylcholine-elicited endothelium-dependent vasodilatation was significantly greater in thoracic aortic segments from the former group. Collectively, the data lend support to the notion that alterations in the inflammatory system may be involved in the macrovascular benefits observed in type 2 diabetes trials and provide credence for the development of anti-inflammatory tools to lower CV risk and CV events in diabetes.

Methotrexate: Revisited efficiency and safety of drug administration in psoriasis patients

The article presents the current data of the literature on methotrexate, which is now one of the most commonly used preparation for the systemic treatment of patients with moderate to severe psoriasis. The following problems are under consideration: estimation by specialists of response to systemic psoriasis therapy and possible therapeutic strategies; selecting initial doses of methotrexate for the treatment of patients with psoriasis; the possibilities of combined use with genetically engineered biological agents and monitoring of therapy. The data from randomized clinical trials on the long-term continuous treatment with methotrexate (efficacy, safety); methods of its administration to patients and time and criteria for long-term effecasy are reported. There are presented the data on the mechanisms of methotrexate action and the new data about the impact on the adenosine metabolism and the ability of the preparation to modulate the inflammatory response in the skin of patients by inhibiting the cellular components of the inflammatory infiltrate in the skin (dendritic antigen-producing cells and T-lymphocytes), as well as the suppression of expression of some proinflammatory cytokines (IFN-y and IL17A).

Mechanism of action of methotrexate in rheumatoid arthritis, and the search for biomarkers

The treatment and outcomes of patients with rheumatoid arthritis (RA) have been transformed over the past two decades. Low disease activity and remission are now frequently achieved, and this success is largely the result of the evolution of treatment paradigms and the introduction of new therapeutic agents. Despite the rapid pace of change, the most commonly used drug in RA remains methotrexate, which is considered the anchor drug for this condition. In this Review, we describe the known pharmacokinetic properties and putative mechanisms of action of methotrexate. Consideration of the pharmacodynamic perspective could inform the development of biomarkers of responsiveness to methotrexate, enabling therapy to be targeted to specific groups of patients. Such biomarkers could revolutionize the management of RA.

Cell-contact-dependent activation of CD4+ T cells by adhesion molecules on synovial fibroblasts

OBJECTIVE

To determine how cell-cell contact with synovial fibroblasts (SF) influence on the proliferation and cytokine production of CD4⁺T cells.

METHODS

Naïve CD4⁺T cells were cultured with SF from rheumatoid arthritis patients, stimulated by anti-CD3/28 antibody, and CD4⁺T cell proliferation and IFN-γ/IL-17 production were analyzed. To study the role of adhesion molecules, cell contact was blocked by transwell plate or anti-intracellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1(VCAM-1) antibody. To study the direct role of adhesion molecules for CD4⁺T cells, CD161⁺or CD161^- naïve CD4⁺T cells were stimulated on plastic plates coated by recombinant ICAM-1 or VCAM-1, and the source of IFN-γ/IL-17 were analyzed.

RESULTS

SF enhanced naïve CD4⁺T cell proliferation and IFN-γ/IL-17 production in cell-contact and in part ICAM-1-/VCAM-1-dependent manner. Plate-coated ICAM-1 and VCAM-1 enhanced naïve CD4⁺T cell proliferation and IFN-γ production, while VCAM-1 efficiently promoting IL-17 production. CD161⁺naïve T cells upregulating LFA-1 and VLA-4 were the major source of IFN-γ/IL-17 upon interaction with ICAM-1/VCAM-1.

CONCLUSION

CD4⁺T cells rapidly expand and secrete IFN-γ/IL-17 upon cell-contact with SF via adhesion molecules. Interfering with ICAM-1-/VCAM-1 may be beneficial for inhibiting RA synovitis.

Insights on methotrexate in psoriatic disease

The folic acid analogue methotrexate is used as an anti-neoplastic agent and treatment for inflammatory disorders including psoriasis, dermatomyositis, lupus erythematous, sarcoidosis, and systemic sclerosis. Despite the introduction of newer biologic agents, methotrexate remains a first-line systemic therapy for many patients with disorders of chronic inflammation. Here we briefly describe the current clinical evidence for methotrexate use in psoriatic disease, our current understanding of methotrexate's anti-inflammatory properties, and the future role of methotrexate in the treatment of immune mediated disorders.

The role of adenosine and adenosine receptors in the immunopathogenesis of multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a heterogeneous neurological disorder with multifactorial etiologies characterized by demyelination, axonal degeneration, and oligodendroglial death. It is believed that both genetics and environmental risk factors such as infection are involved in disease etiology. Accumulating evidence indicates that alteration in purinergic system signaling is involved in immunity and inflammation. Adenosine, a key purine nucleoside, has been shown to be produced during metabolic stress, including ischemia, inflammatory condition, and tissue injury.

METHODS

Extracellular adenosine directly affects various physiological and pathological processes of MS by stimulating G protein-coupled adenosine receptors A1, A2A, A2B, and A3 on the surface of immune cells. It has been suggested that promotion of adenosinergic system may be an important factor in MS pathophysiology and considered as promising therapeutic target for this disease.

CONCLUSION

In this review, we will discuss about the immunopathologic effects of adenosine on MS and its animal model, experimental autoimmune encephalomyelitis.

Matrix metalloproteinase-10 is a target of T and B cell responses that correlate with synovial pathology in patients with antibiotic-refractory Lyme arthritis

Infection-induced autoimmunity is thought to be a contributing factor in antibiotic-refractory Lyme arthritis, but studies of autoimmunity have been hindered by difficulty in identifying relevant autoantigens. We developed a novel approach that begins with the identification of T cell epitopes in synovial tissue using tandem mass spectrometry. Herein, we identified an immunogenic HLA-DR-presented peptide (T cell epitope) derived from the source protein matrix metalloproteinase-10 (MMP-10) from the synovium of a patient with antibiotic-refractory arthritis. This finding provided a bridge for the identification of autoantibody responses to MMP-10, the "first autoimmune hit" in a subgroup of patients with erythema migrans, the initial skin lesion of the infection. Months later, after priming of the immune response to MMP-10 in early infection, a subset of patients with antibiotic-responsive or antibiotic-refractory arthritis had MMP-10 autoantibodies, but only patients with antibiotic-refractory arthritis had both T and B cell responses to the protein, providing evidence for a "second autoimmune hit". Further support for a biologically relevant autoimmune event was observed by the positive correlation of anti-MMP-10 autoantibodies with distinct synovial pathology. This experience demonstrates the power of new, discovery-based methods to identify relevant autoimmune responses in chronic inflammatory forms of arthritis.

Management of rheumatoid arthritis: Impact and risks of various therapeutic approaches

Rheumatic diseases are highly prevalent chronic disorders and the leading cause of physical disability worldwide, with a marked socio-economic impact. Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease of unknown etiology with an autoimmune pathogenesis, characterised by arthropathy with chronic, deforming, destructive evolution and multiple systemic manifestations. The management of RA has undergone significant changes as far as objectives and approaches are concerned, ending in the current strategy known as ‘treat to target’. The therapeutic array of RA includes several categories of medicinal products, of varying potential. There are several criteria for the classification of medicinal products used against this disease, one of the most important and modern of which divides such substances according to their effects on the progress of the disease: symptom-modifying antirheumatic drugs (including non-steroidal anti-inflammatory drugs and corticoids), disease-modifying antirheumatic drugs (including various substances, such as gold salts, antimalarials, sulfasalazine, D-penicillamine; non-specific immunosuppressive medication, such as methotrexate, cyclophosphamide, azathioprine and leflunomide) and biological therapy is a recent addition, providing new insight into the treatment of this disease. The selection of the optimal therapy for RA should be based on guidelines and recommendations, but also on clinical particular aspects and patient preferences.

The Incidence and Predictors of Infection in Psoriasis and Psoriatic Arthritis: Results from Longitudinal Observational Cohorts

Objective.

To investigate the rate, type, characteristics, and predictors of infection in a cohort of patients with psoriatic arthritis (PsA) and a cohort of patients with psoriasis without arthritis (PsC).

Methods.

A cohort of patients with PsA and a cohort of patients with PsC were followed according to a standard protocol and information on the occurrence of infections was recorded. The rate of infection was estimated by fitting an exponential model. A Weibull regression model was fitted to estimate the relative risk of first infection associated with a number of covariates. Risk factors for recurrent infections were investigated using generalized estimating equations.

Results.

There were 498 and 74 infections reported among 695 and 509 patients with PsA and PsC, respectively, with an incidence rate of 19.6 per 100 person-years in the PsA cohort compared with 12.2 in the PsC cohort. The HR of the time to the first infection in PsA versus PsC was 1.6 (p = 0.002), and higher in patients treated with biologics versus nonbiologics at 1.56 (95% CI 1.22–2.00) in PsA and 1.50 (95% CI 0.64–3.54) in the PsC cohorts. Female sex and treatment with biologics were associated with infection in the PsA cohort, whereas a lower Psoriasis Area and Severity Index score and a higher Functional Comorbidity Index were associated with infection in the PsC cohort. Ultraviolet treatment was protective against infection in both cohorts. No difference in rates of hospitalization was found (p = 0.66). There were no infection-related deaths in either cohort.

Conclusion.

The incidence rate of infection was higher in the PsA than the PsC cohort and higher among patients treated with biologics. The data confirm the association between infection and biologic treatment in psoriatic disease.