scholarly journals The molecular and cellular basis of corticosteroid resistance

2003 ◽  
Vol 179 (3) ◽  
pp. 301-310 ◽  
Author(s):  
IC Chikanza ◽  
D Kozaci ◽  
Y Chernajovsky

Corticosteroids (CS) can modulate gene expression and are often used to treat a range of immunological and inflammatory diseases such as asthma, inflammatory bowel disease and rheumatoid arthritis. However, a proportion of patients fail to show an adequate response. On this basis patients have been subdivided into CS-sensitive (SS) and -resistant (SR) subgroups. The ability of CS to inhibit peripheral blood T cell proliferation in vitro has also been used similarly. In rheumatoid arthritis (RA), the in vitro-defined SS and SR subgroups correlate with the clinical responses to CS therapy. The mechanisms responsible for this observation are unknown but they appear to involve a number of known molecular events related to the described mechanisms of action of CS. These include alterations in the functional status of CS receptor-alpha, perturbations of the cytokine and hormonal milieu and intracellular signalling pathways. Peripheral blood mononuclear cells (MNCs) from SR significantly overexpress activated NF-kappaB. In vitro, CS fail to significantly inhibit concanavalin A (conA)-induced NF-kappaB activation in MNCs from SR RA patients. The alterations in the intracellular signalling pathways may explain in part our observations seen in SR RA subjects, CS fail to significantly inhibit conA-induced interleukin (IL)-2 and IL-4 secretion and lipopolysaccharide-induced IL-8 and IL-1beta secretion in vitro. CS therapy fails to reduce the circulating levels of IL-8 and IL-1beta in RA patients. In asthma, CS fail to induce L10 in SR asthma patients. Other molecular mechanisms such as enhanced AP-1 expression and alterations in the MAP kinase pathway are most likely to be involved too and we are currently investigating such possibilities. A full understanding of the molecular basis of SR will lead to the development of more rational therapeutic strategies.

1978 ◽  
Vol 148 (5) ◽  
pp. 1429-1434 ◽  
Author(s):  
L Slaughter ◽  
D A Carson ◽  
F C Jensen ◽  
T L Holbrook ◽  
J H Vaughan

Peripheral blood mononuclear cells from 10 patients with rheumatoid arthritis and 9 control subjects were cultured in vitro for 30 days with and without infection by Epstein-Barr virus. All cultures showed polyclonal stimulation of B cells as indicated by rising levels of IgM in the culture supernates, reaching maximal at 18-24 days, and with no quantitative or kinetic difference between the RA and control cells. IgM anti-IgG was also produced in both groups and maximally at 18-24 days, but in greater quantity by the RA lymphocytes. The anti-IgG made by the RA lymphocytes was more easily absorbed by solid phase IgG than was the anti-IgG made by the normal lymphocytes and thus was judged to be of higher affinity. RA lymphocytes uninfected with EBV had higher transformation scores than did the normal controls and developed spontaneously into permanent cell lines in six instances.


2019 ◽  
Author(s):  
Hui-Hsin Chang ◽  
Ching-Huang Ho ◽  
Beverly Tomita ◽  
Andrea A. Silva ◽  
Jeffrey A. Sparks ◽  
...  

AbstractDespite the development of several targeted therapies for rheumatoid arthritis (RA), there is still no reliable drug-specific predictor to assist rheumatologists in selecting the most effective targeted therapy for each patient. Recently, a gene signature caused by impaired induction of PTPN22 in anti-CD3 stimulated peripheral blood mononuclear cells (PBMC) was observed in healthy at-risk individuals. However, the downstream target genes of PTPN22 and the molecular mechanisms regulating its expression are still poorly understood. Here we report that the PTPN22 gene signature is also present in PBMC from patients with active RA and can be reversed after effective treatment. The expression of PTPN22 correlates with that of more than 1000 genes in Th cells of anti-CD3 stimulated PBMC of healthy donors and is inhibited by TNFα or CD28 signals, but not IL-6, through distinct mechanisms. In addition, the impaired induction of PTPN22 in PBMC of patients with active RA can be normalized in vitro by several targeted therapies. More importantly, the in vitro normalization of PTPN22 expression correlates with clinical response to the targeted therapies in a longitudinal RA cohort. Thus, in vitro normalization of PTPN22 expression by targeted therapies can potentially be used to predict clinical response in a drug-specific manner.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Klára Prajzlerová ◽  
Olga Kryštůfková ◽  
Petra Hánová ◽  
Veronika Horváthová ◽  
Monika Gregová ◽  
...  

AbstractIndividuals carrying anti-citrullinated protein antibodies (ACPA) are considered at high risk of developing rheumatoid arthritis (RA). The altered expression of miRNAs contributes to the pathogenesis of RA. We aimed to identify differentially expressed miRNAs in the peripheral blood of ACPA-positive individuals with arthralgia at risk of RA compared to healthy controls (HC) and to determine their implications in the preclinical phase of RA. A comprehensive analysis of miRNAs revealed the dysregulation of miR-451 in peripheral blood mononuclear cells (PBMC) and plasma from RA-risk individuals. Higher miR-451 expression in PBMC from RA-risk individuals was further validated. Notably, miR-451 was previously shown to regulate CXCL16, a protein involved in RA pathogenesis. The expression of miR-451 in PBMC positively correlated with the CXCL16 mRNA, which could be secondary to the inflammation-induced expression of miR-451. Transfection of monocytes with pre-miR-451 in vitro resulted in the downregulation of CXCL16. Moreover, flow cytometry revealed a lower count of CXCL16-positive monocytes in RA-risk individuals. We propose that the constitutive or inflammation-induced upregulation of miR-451 in PBMC downregulates the expression of CXCL16, reduces the inflammatory milieu and thereby strives to delay the shift from the preclinical phase to the clinical manifestation of RA. This hypothesis warrants further investigation.


Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1037
Author(s):  
Patricia Ruiz-Limon ◽  
Maria L. Ladehesa-Pineda ◽  
Clementina Lopez-Medina ◽  
Chary Lopez-Pedrera ◽  
Maria C. Abalos-Aguilera ◽  
...  

Endothelial dysfunction (ED) is well known as a process that can lead to atherosclerosis and is frequently presented in radiographic axial spondyloarthritis (r-axSpA) patients. Here, we investigated cellular and molecular mechanisms underlying r-axSpA-related ED, and analyzed the potential effect of peripheral blood mononuclear cells (PBMCs) in promoting endothelial injury in r-axSpA. A total of 30 r-axSpA patients and 32 healthy donors (HDs) were evaluated. The endothelial function, inflammatory and atherogenic profile, and oxidative stress were quantified. In vitro studies were designed to evaluate the effect of PBMCs from r-axSpA patients on aberrant endothelial activation. Compared to HDs, our study found that, associated with ED and the plasma proatherogenic profile present in r-axSpA, PBMCs from these patients displayed a pro-oxidative, proinflammatory, and proatherogenic phenotype, with most molecular changes noticed in lymphocytes. Correlation studies revealed the relationship between this phenotype and the microvascular function. Additional in vitro studies confirmed that PBMCs from r-axSpA patients promoted endothelial injury. Altogether, this study suggests the relevance of r-axSpA itself as a strong and independent cardiovascular risk factor, contributing to a dysfunctional endothelium and atherogenic status by aberrant activation of PBMCs. Lymphocytes could be the main contributors in the development of ED and subsequent atherosclerosis in this pathology.


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