Electrophoretic Immunoassays for Oral Diagnostics

C-reactive protein (CRP) is the prototypic human acute-phase protein and is found at increased levels in the blood during episodes of inflammation. CRP was generally thought to be produced only by hepatocytes; however, several studies have shown extrahepatic synthesis of CRP. A previous study showed that PM10 and ultrafine carbon black (ufCB) were able to induce CRP expression in A549 cells. This study aims to examine the factors that lead to the production of CRP in A549 cells. A549 human lung epithelial cells were treated with cytokines (interleukin 6, tumor necrosis factor α, interferon γ, or interleukin 1β) or carbon particles (CB and ufCB) for 18 h. It was found that CRP could be expressed within the cells and that CRP was secreted from the cells particularly with tumor necrosis factor α, CB and ufCB treatments. It was also found that this expression of CRP with CB and ufCB treatments was dependent on nuclear factor kappa B (NFκB). The expression of CRP in A549 cells may indicate an important role for CRP expression and secretion from lung epithelial cells in response to inflammatory stimuli.

This article describes a simple and rapid fabrication method for microfluidic chip with three-dimensional (3D) structures by using natural lotus leaf as a template. This microfluidic chip consists of one PDMS artificial lotus leaf substrate with micro/nano hierarchical structure and one PDMS replica with microfluidic network. PDMS artificial lotus leaf substrate is directly replicated from natural lotus leaf template by soft lithography technology. In order to seal this rough PDMS artificial lotus leaf substrate against PDMS replica, a PDMS adhesive-assisted bonding method is developed to assist the sealing of our microfluidic chip. Compared to previously reported microfluidic chips with 3D structures based on MEMS/NEMS technology, the rapid fabrication of our microfluidic chip against a natural lotus leaf template is simple, low cost, easy to control, and highly faithful without the need of expensive MEMS facility and clean room condition. As an application demonstration, we fabricate a microfluidic immunosensing chip for C-reactive protein (CRP) detection by taking advantage of its high surface area. The experiment result shows that our microfluidic chip with 3D structures has more than five times higher sensitivity than those obtained from the conventional microfluidic chip with a flat channel wall due to the increase of the surface area and consequent increase of the amount of immobilized antibody. The present microfluidic chip with 3D structures also can be applied in proteins microarray, cell culture, cell adhesion, and so on.

To the Editor: Recent data from Veterans Affairs High-Density Lipoprotein Cholesterol Intervention Trial (VA-HIT) have recently reported that pharmacological treatment with a fibrate (gemfibrozil) significantly reduced coronary heart disease (CHD) risk among men with a history of CHD who had low HDL-cholesterol and LDL-cholesterol levels at baseline evaluation.1 Moreover, this study also demonstrated that changes in the lipoprotein-lipid profile only partially explained the beneficial effect of gemfibrozil on CHD risk, suggesting that other factors may be responsible for the reduction in the risk of CHD observed among patients undergoing fibrate therapy.2 On the other hand, the contribution of inflammation to the development of atherosclerosis and CHD is increasingly recognized, and recent studies have identified some inflammatory markers, such as plasma C-reactive protein (CRP) and cytokines, as CHD risk factors.3,4 ⇓ Recent data have suggested that statins and fibrates may favorably decrease markers of inflammation.5–8 ⇓ ⇓ ⇓ However, the effect of fibrates among abdominally obese men with the atherogenic dyslipidemia of the metabolic syndrome (a condition associated with markedly elevated inflammatory markers) has, to the best of our knowledge, never been reported. Thus, the aim of the present study was to examine the effect of a 6-month fibrate treatment on plasma CRP concentrations and cytokine levels such as interleukin …

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Incubation of murine tumor necrosis factor (mTNF) at subnanomolar concentrations results in partial dissociation of the trimers, coinciding with a decrease in bioactivity. Using size-exclusion chromatography, we observed that the conversion of labeled mTNF to monomers is not only prevented by coincubation with an excess of unlabeled mTNF but also with unlabeled human TNF (hTNF). Moreover, after coincubation of mTNF and hTNF four different TNF complexes were revealed by native polyacrylamide gel electrophoresis, viz. homotrimeric mTNF and hTNF, as well as two complexes with an intermediate migration pattern. Analytical gel filtration in combination with native polyacrylamide gel electrophoresis and Western blot immunodetection indicated that these new complexes consisted of heterotrimeric TNF molecules. We conclude that an exchange of monomers takes place during coincubation of two different species of TNF, which results in homotrimeric and heterotrimeric TNF. To assess receptor interaction in vitro, TNF heterotrimeric molecules were used as obtained after incubation of mTNF with labeled hTNF (which only binds to mTNF receptor I) or with labeled mutein mTNF75 (specific for mTNF receptor II). These heterotrimers were retained by both mTNF receptors, which means that the mTNF subunits incorporated in heterotrimeric complexes still can bind to both types of TNF receptor. In addition, the gradual decrease in mTNF bioactivity during preincubation at subnanomolar concentrations was prevented by the presence of mutein mTNF75, which is inactive in an L929 cytotoxicity assay, indicating that heterotrimerization can influence the overall bioactivity.

This paper presents the development of a plastic microfluidic immunosensor for rapid, reliable and on-the-spot detection of disease biomarkers in human sera. The microfluidic chips were fabricated in cyclic polyolefin by hot-embossing with a silicon master mold. The master itself was made using photolithographic techniques and Deep Reactive Ion Etching (DRIE). As a platform model, serum concentrations of C-reactive protein (CRP), a cardiac and inflammation marker, was measured on-chip using chemiluminescence based immunoassay. The assay results were read via an on-board instant photographic film, and with an imager capable of detecting chemiluminescent signals. The on-board detection module obviates the need for any dedicated bench-top analyzer for reading the immunoassay results, and therefore makes the device self-sufficient for point-of-care diagnostics when simple positive/negative results are sought. The microfluidic chemiluminescence results were compared with standard microplate ELISA analysis to assess the accuracy of the developed microfluidic immunoassay. Screening of CRP in human serum samples showed good correlation with ELISA analysis and the mean difference between the two methods using the Bland and Altman method was -0.079 +/- 0.858 mg/L for hsCRP. With approximate assay times of 25 min, the developed microfluidic immunoassay approach shows great potential for rapid plus sensitive detection of disease markers at the point-of-care.

Breast cancer provides a typical example of an inflammation-linked malignant disease. The inflammatory components present in the tumor microenvironment contribute to the further progression of the disease. The present study was conducted to evaluate the correlation between levels of proinflammation cytokines tumor necrosis factor α, interleukin 1β, interleukin 6, C-reactive protein and tumor recurrence in breast cancer patients. Seventy two breast cancer patients with histologically proven diagnosis and 15 healthy donors were enrolled into study. Thirty one patients with progression of the disease and 41 patients with clinical stabilization (conditional remission) were included to “progression” and “remission” groups respectively. This division of breast cancer patients was made during the 3 years study. The levels of proinflammation cytokines – tumor necrosis factor α, interleukin 1β, interleukin 6 and C-reactive protein were revealed. This cytokines in bone marrow and peripheral blood act as a specific microenvironment and was found that the elevated levels of this cytokines were strongly associated with progression of breast cancer. The data showed that most prominent predictive markers of tumor recurrence are high levels of indicated cytokines in combination with other markers (C-reactive protein; disseminated tumor cells in bone marrow). Determination of the high levels of tumor necrosis factor, interleukin 1β, interleukin 6 in bone marrow and peripheral blood of breast cancer patients are important to establish the features of bone marrow microenvironment for prediction of metastasis and correction antitumor therapy. Keywords: breast cancer, proinflammatory cytokines, bone marrow, peripheral blood, disseminated tumor cells.

Protein separation with electrophoresis in native state (native Polyacrylamide Gel Electrophoresis, native PAGE) is rarely applied in laboratory which results in limited scientific report. Native PAGE result can be used in further assay analysis or shows important protein-protein interaction. This study aimed to investigate immunoglobulin Y(IgY) behavior in separation using native PAGE. IgY protein is used since many properties of IgY are already known. IgY was isolated from follicles yolk and examined using clear native PAGE (CN-PAGE) and Sodium Dodecyl Sulphate (SDS) PAGE, both in reducing and nonreducing condition. CN-PAGE electropherogram of IgY showed streaked band from ~409-1048 kDa indicating IgY aggregation. Whereas SDS-PAGE in reducing condition showed normal result, ~68 kDa and ~18,7 kDa protein bands correlated with heavy and light chain of IgY respectively. Moreover SDS PAGE in nonreducing condition also resulted in normal IgY band sized ~185 kDa. Dilution and disaggregation using sodium dodecyl sulphate (SDS), sodium deoxycholate (SDC), sarcosyl, urea, and glycerol did not affect the migration behavior. We concluded that IgY is not in aggregate form. Migration behavior of IgY in CN-PAGE which was slow, produced streaked band, and appeared to have very high molecular weight is possibly due to low electronegativity (pI = 6,6±0,9) in CN-PAGE condition (buffer pH 8,3) and planar conformation of IgY. Keywords: electrophoresis, immunoglobulin Y, native PAGE.

Research on microfluidic devices for biological analysis has progressed sufficiently to be developed into point-of-care diagnostics products. The goal of this thesis is to improve multiple aspects of capillary-driven microfluidic devices. In particular, the objective is to provide devices with a fast time to result, that are simple to use (one-step), that can be portable, that accept a variety of samples, that operate reliably, that provide a range of detection signals, that are mass manufacturable at lost cost, and that are able to detect medically relevant biological molecules. First, we survey the evolution of microfluidic research into portable medical diagnostic devices. By looking at several gaps and opportunities in current medical diagnostics, we provide an overview of research topics that have the potential to shape the next generation of point-of-care diagnostics. Specifically we explain technologies in the order of sample interacting with different components of a device. We investigate the materials, surface treatments, sample processing, microfluidic elements (such as valves, pumps and mixers), receptors and analytes and the integration of these components into a device that might conceivably leave the laboratory for the hands of consumers. The knowledge of what is important in a point-of-care diagnostics device was used to develop a proof of concept. One of the main challenges is to make microfluidics easy to use by incorporating reagents and microfluidic elements. We integrated a number of functional elements on a chip such as a sample collector, delay valves, flow resistors, a deposition zone for detection antibodies (dAbs), a reaction chamber sealed with a polydimethylsiloxane (PDMS) substrate, and a capillary pump and vents. We further incorporated capture antibodies (cAbs), detection antibodies (dAbs) and analyte molecules for making one-step immunoassays. The integrated microfluidic chip requires only the addition of sample to trigger a sequence of events controlled by capillary forces to detect C-reactive protein (CRP), a general inflammation and cardiac marker, at a concentration of 1 ng mL-1 within 14 min using only 5 µL of human serum. The proof-of-concept is extended to easily modify several assay parameters such as the flow rates and the volumes of samples for tests, and the type of reagents and receptors for analytes. The multiparametric microfluidic chip is capable of analyzing 20 µL of human serum in 6 parallel flow paths in a range of flow rates with filling times from 10 minutes to 72 minutes. The asymmetric release of dAbs in a stream of human serum is compensated by a Dean flow mixer. Sample is equally split into 6 reaction chambers connected to flow resistances that vary flow rates, and the kinetics of capture of analyte-dAb complexes. The increased incubation time leads to a fourfold increase in detection signal in the reaction chamber with the longer incubation time. Furthermore, integrating reagents and controlling their release is essential for simple and accurate point-of-care diagnostic devices. We developed reagent integrators (RIs) to release small amounts of dried reagents (ng quantities and less) into microliters of sample. Typical RIs are composed of an inlet splitting into a central reagent channel, with a high hydraulic resistance, and two diluter channels. Reagents spotted in the central channel reconstitute in sample during filling and merge at the end of the RI with a dilution factor corresponding to the relative hydraulic resistance of the channels forming the RI. RIs are simple to integrate in lateral flow assays and provide a great degree of control over reagent integration and dissolution. Finally, the one-step capillary-driven microfluidic chips have the ability to not only detect a variety of proteins, but also to detect nucleic acids for molecular diagnostics. These devices, especially if manufactured in low cost plastic and used with portable fluorescence readers, have the potential to identify a wide variety of health conditions and to enable truly decentralized medical diagnostics.

Active droplet-array microfluidics-based chemiluminescence immunoassay for point-of-care detection of procalcitonin

Aims: To study the influence of type 2 diabetes mellitus (DM) and depression on subclinical inflammation in patients with myocardial infarction (MI). Material and methods: 195 patients with a median (Me) age of 58 years (54, 65), admitted to hospital with ST segment elevation myocardial infarction were enrolled in a case-control study. 99 patients (51%) with Me age of 60 years (54, 64) had DM, 96 (49%) with Me 58 years (54, 62) – did not. The age differences between the groups was not considered statistically significant. Diabetic and non-diabetic patients were subdivided into groups according to the depression degree: with depression and without. The levels of interleukin (IL-6, IL-8, IL-10), tumor necrosis factor (TNF), high-sensitivity C-reactive protein (CRP) were measured by solid-phase enzyme immunoassay on 3rd - 5th days after MI onset. Results: Diabetic patients found higher subclinical inflammatory activity than non-diabetic: IL-6 9.4 (4.9, 11.4) pg/ml and 4.4 (3.6, 5.1) pg/ml, p = 0.02, IL-8 6.4 (4.9, 10.9) pg/ml and 3.7 (2.7, 7.3) pg/ml, p = 0.04, IL -10 3.5 (1.9, 4.1) pg/ml and 6.5 (4.1, 7.2) pg/ml, p = 0.02, TNF 11.7 (9.8, 16.5) pg/ml and 6.9 (5.8, 11 2) pg/ml, p = 0.03; CRP 19.9 (14.6, 23.2) mg/L and 11.4 (7.6, 14.6) mg/L, p = 0.01.The depression provoked subclinical inflammation in MI patients independently of diabetes. Non-diabetic MI patients without depression reported lower level of subclinical inflammation, than those with depression: IL-6, 3.8 (2.9, 3.8) pg/ml and 1.1 (1.5, 2, 5) pg/ml, p=0.03, IL-8 1.9 (1.7, 4.3) pg/ml and 3.6 (2.1, 5.9) pg/ml, p=0.02, IL-10 5.1 (2.8, 4.5) pg/ml and 2.8 (2.5, 3.3) pg/ml, p=0.04, TNF 3.8 (3, 3, 6.8) pg/ml and 6.2 (5.1, 8.7) pg/ml, p=0.04, CRP 6.9 (4.8, 8.5) mg/l and 9.1 (5.6, 12.2) mg/L, p=0.03. Diabetic MI patients without depression found lower levels of inflammation markers than those with depression: IL-6, 4.9 (2.1, 6.5) pg/ml and 6.9 (3.9; 8.1) pg/ml, p=0.02, IL-8 3.4 (2.7, 6.3) pg/ml and 6.1 (4.4, 9.1) pg/ml, p=0.04, IL-10 2.9 (1.5, 3.5) pg/ml and 1.1 (0.9, 1.3) pg/ml, p=0.03, TNF 6.7 (5.7, 9.3) pg/ml and 9.9 (8.2, 14.5) pg/ml, p=0.01, CRP 12.9 (8.5, 13.9) mg/l and 14.1 (12.3, 18.6) mg/L, p=0.04. The lowest subclinical inflammatory activity was reported in non-diabetic MI patients without depression, while the highest level - in their combination. Conclusions: DM and depression in MI patients contributed to pronounced subclinical inflammatory activity, which may be associated with MI severity as well as common pathogenesis of these diseases.

Although C-reactive protein (CRP) is a representative acute-phase protein produced by hepatocytes, the role of CRP in liver innate immunity remains unclear. Using C57BL/6 mice, the present study investigated how CRP affects the functions of liver macrophages, Kupffer cells, and natural killer / natural killer T (NK/NKT) cells under various conditions, including Escherichia coli infection, septic shock, and multiorgan dysfunction induced by interleukin (IL)-12/lipopolysaccharide (LPS) (generalized Shwartzman reaction [GSR]), and LPS-induced lethal hepatitis in Propionibacterium acnes-primed mice. When mice were challenged with a lethal dose of E. coli, synthetic CRP peptide decreased the mortality without decreasing serum tumor necrosis factor (TNF), presumably by enhancing the phagocytic activity of Kupffer cells. Synthetic CRP greatly decreased the production of TNF and reactive oxygen species from Kupffer cells and thereby rescued mice after lethal LPS challenge. CRP also decreased the mortality from GSR and lethal hepatitis by inhibiting TNF production from Kupffer cells, especially phagocytosing Kupffer cells. However, interferon-gamma production from NK/NKT cells was generally not so affected. CRP reportedly binds to FcgammaRI and FcgammaRII, and the injection of anti-FcgammaRII/III Ab into mice abrogated TNF production from, but increased the phagocytic activity of, Kupffer cells. Furthermore, CRP pretreatment restored the decreased phagocytic activity of Kupffer cells in burn-injured mice and decreased TNF production by Kupffer cells and thereby inhibited mortality after sublethal E. coli infection. If CRP was injected into mice at 1 hour after lethal E. coli challenge, it slightly but significantly increased the survival rate. CRP thus enhances the phagocytosis of Kupffer cells but decreases their TNF production in a complex manner in which the pathway by way of FcgammaRII may be involved.

Exercise training during the dialytical procedure may have positive cardiovascular effects and prevent or revert muscle wasting in patients undergoing chronic hemodialysis. To evaluate the effects of an exercise training program in patients undergoing chronic hemodialysis. Fifteen patients on chronic hemodialysis aged 21 to 69 years (three females) were included in the study. Nine of these were included in an exercise training program. During 16 weeks, exercise sessions were carried out during each dialytical procedure that included a warm-up period, aerobic exercises done using standing cycles, and resistance exercises, performed using Thera-Band(®) elastic bands and loops. Borg scale was used to control the intensity of training. At baseline and at the end of the study, a blood sample prior and after the dialytical procedure was obtained to measure C reactive protein, tumor necrosis factor α and interleukin 6. Quadriceps muscle strength, six minutes' walk and quality of life using the SF-36 questionnaire, were also measured. Four experimental subjects did not complete the study period, two that withdrew before starting, one due to problems with the venous access and one that decided to withdraw after 1 month of training. Among the five patients that finished the training period, significant improvements in the six minutes' walk and quadriceps strength were observed in the experimental group. No significant changes were observed among controls. No changes were observed in either group in C reactive protein, tumor necrosis factor and interleukin 6 levels or quality of life. Among patients undergoing chronic hemodialysis exercise training improves endurance and muscle strength.

Objective To observe the changes of postoperative blood high sensitive C-reactive protein (hs-CRP), tumor necrosis factor(TNF)-o, P-selectin levels in patients with acute coronary syndrome (ACS) who had an atorvastatin intensive treatment before operation, and investigate its clinical significance.Methods Seventy-eight cases of ACS patients who intended to undergo percutaneous coronary intervention were divided into two groups by random digits table:39 patients comprising the standard treatment group (given atorvaatatin 20 mg/d, conventional treatment), 39 patients comprising the enhanced group (given atorvastatin 40 mg, 20 mg separately at preoperative 12 h, 2 h on the basis of conventional treatment).Among them, 28 cases of the standard treatment group and 29 cases of the enhanced group finally underwent the test. The hs-CRP,TNF-α ,P-selectin levels at preoperative 1 day,postoperative 6 h,postoperative 12 h were detected and then the changes of three factors were analyzed. Results There was no significant difference in hs-CRP,TNF- α, P-selectin between the two groups at preoperative 1 day. The values of the two groups markedly increased at postoperative 6 h, 12 h and the difference was statistically significant (P ＜0.05). The values of the standard treatment group were markedly higher at postoperative 12 h than those at postoperative 6 h,and the difference was statistically significant [hs-CRP: (10.29 ± 0.77) mg/L vs. (6.34 ±1.23) mg/L;TNF-α: (58.15±5.19) ng/L vs. (36.12 ± 3.89) ng/L;P-selectin: (49.58 ±4.92) μg/L vs.(31.47 ± 3.71) μ g/L] (P ＜ 0.05). However, the values of the enhanced group were higher at postoperative 12 h than those at postoperative 6 h but the difference was no statistically significant [hs-CRP: (6.83 ± 1.46)mg/L vs. (5.95 ± 1.17) mg/L; TNF- o: (42.18 ± 7.79) ng/L vs. (34.07 ± 8.79) ng/L; P-selectin: (33.57 ±4.63) μ g/L vs. (29.78 ± 5.61) μ g/L] (P ＞ 0.05). Three factors in standard treatment group were elevating significantly at postoperative 6 h, 12 h compared with those in the enhanced group, but the difference was no statistically significant (P ＞ 0.05). Conclusion Short-term intensive therapy of atorvastatin in ACS patients who intend to do PCI, can reduce the hs-CRP, TNF-α, P-selectin levels effectively. Key words: Coronary disease; Angioplasty,transluminal,percutaneous coronary; C-reactive protein; Tumor necrosis factor-alpha; P-selectin

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation and joint destruction. Both inflammatory response and oxidative stress contribute to the pathogenesis of RA. Oxidative damage can induce and aggravate the imbalance of immune inflammation and promote cell and tissue damage. In this study, the expression of long non-coding RNA (lncRNA) LINC00638 in peripheral blood of patients with RA damp-heat arthralgia syndrome was observed, and the correlation between LINC00638 and disease activity, immune inflammation and oxidative stress indicator was investigated. Subsequently, the mechanisms for LINC00638 in regulating the inflammatory response and oxidative stress in RA fibroblast-like synoviocyte (FLS) under the condition of overexpression and interference were further explored. In this study, 48 RA patients with damp-heat arthralgia syndrome and 27 normal healthy subjects, who came from Department of Rheumatology, First Affiliated Hospital of Anhui University of Chinese Medicine, were included; and they were divided into a RA group and a control group. The expression of LINC00638 in peripheral blood mononuclear cells (PBMC) from the subjects was detected by real-time PCR. Enzyme linked immunosorbent assay (ELISA) was used to detect serum interleukin (IL)-10, IL-17, tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), heme oxygenase 1 (HO-1) and superoxide dismutase 2 (SOD2) expression. Spearman method was used to study the relationship between LINC00638 and erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), anti-cyclic citrullinated peptide antibody (anti-CCP), and to observe the relation between LINC00638 and the Disease Activity Score of 28 Joint (DAS28), Quantitative Score of Damp Heat Syndrome, Visual Analogue Scale (VAS), Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). RA-FLS was induced by RA-PBMC, and the RA in vitro cell experimental model was established. LINC00638 overexpression plasmid and small interfering RNA (siRNA) were constructed and transfected into RA-FLS. The cell experiments were divided into 4 groups: a pcDNA3. 1- control group, a pcDNA3.1-LINC00638 group, a siRNA-control group, and a siRNA-LINC00638 group. The transfection efficiency of overexpression plasmid and siRNA was detected by real-time PCR, the expression of TNF-α and IL-10 was detected by ELISA, and the expression of antioxidant proteins HO-1 and SOD2 was detected by immunofluorescence. Compared with the control group, the expression of LINC00638 in the RA group was lower (P<0.01). The area under the curve (AUC) of the receiver operating characteristic (ROC) curve of LINC00638 was 0.9271. The DAS28 in RA group was 5.70 (5.40-6.50), the Quantitative Score of Damp-heat Syndrome was 20.0 (17.0-23.0), and the VAS score was 7.0 (6.3-8.0). Compared with the control group, the ESR, CRP, RF, anti-CCP, SAS and SDS scores in the RA group were significantly increased (all P<0.01). Spearman correlation analysis showed that: LINC00638 was negatively correlated with ESR (r=-0.532, P<0.01), CRP (r=-0.367, P<0.05), TNF-α (r=-0.375, P<0.01), MDA (r= -0.295, P<0.05), DAS28 (r=-0.450, P<0.01), and which was positively correlated with SOD2 (r=0.370, P<0.05). After the induction of RA-FLS, the expression level of LINC00638 was significantly decreased (P<0.01), indicating that the stimulation of PBMC could effectively reduce the expression of LINC00638 in RA-FLS, so the experimental model of RA-FLS-induced by PBMC was utilized. Compared with the pcDNA3.1-control group, the expressions of LINC00638, IL-10, SOD2, and HO-1 in the pcDNA3.1-LINC00638 group were significantly increased (all P<0.01), and the expression of TNF-α was decreased (P<0.01). Compared with siRNA-control group, LINC00638, IL-10, SOD2 and HO-1 in the siRNA-LINC00638 group were significantly decreased (all P<0.01), and TNF-α was significantly increased (P<0.01). LINC00638 is down-regulated in the peripheral blood of RA patients with damp-heat arthralgia syndrome, which is correlated with disease activity, immune inflammation and oxidative stress. Overexpression of LINC00638 can down-regulate pro-inflammatory factors, up-regulate anti-inflammatory factors, and increase antioxidant enzyme activity, thereby improving inflammation and oxidative stress in RA. LINC00638 is the differential lncRNA obtained by the research group's previous high-throughput sequencing of the whole transcriptome of peripheral blood PBMCs in RA patients and validation of clinical samples. In order to deepen the molecular biology research of this gene, the microRNA and mRNA targeted by LINC00638 can be further studied from the perspective of competing endogenous RNAs.