Serum Interferon-inducible Protein-10 Research Articles

Cytokine profile in Egyptian children and adolescents with COVID‐19 pneumonia: A multicenter study

BackgroundTo date, the cytokine profile in children and adolescent with novel coronavirus disease 2019 (COVID‐19) has not been reported.ObjectivesWe investigated serum levels of a panel of key cytokines in children and adolescent with COVID‐19 pneumonia with a primary focus on “cytokine storm” cytokines such as interleukin (IL)‐1β, IL‐6, IL‐17, IL‐2, IL‐4, IL‐10, interferon (IFN‐γ), tumor necrosis factor (TNF)‐α, and two chemokines interferon‐inducible protein‐10 (IP‐10) and IL‐8. We also studied whether these cytokines could be potential markers for illness severity in COVID‐19 pneumonia.MethodsNinety‐two symptomatic patients aged less than 18 years with confirmed COVID‐19 pneumonia and 100 well‐matched healthy controls were included in this multi‐center study. For all patients, the presence of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in respiratory fluid specimens was detected by real‐time reverse‐transcriptase polymerase chain reaction. We measured serum concentrations of studied cytokines by using flow cytometry.ResultsPatients with COVID‐19 had significantly higher median IL‐1β, IL‐6, IL‐8, IL‐10, IL‐17, TNF‐α, and IP‐10 serum levels than did control children (all p < 0.01). Patients with severe COVID‐19 pneumonia had significantly higher median IL‐1β, IL‐6, and IP‐10 serum levels as compared with those with moderate COVID‐19 pneumonia; all p < 0.01. ROC analysis revealed that three of the studied markers (IL‐6, IL‐1β, and IP‐10) could predict severe COVID‐19 pneumonia cases with the largest AUC for IL‐6 of 0.893 (95% confidence interval: 0.84–0.98; p < 0.01).ConclusionOur study shows that pediatric patients with COVID‐19 pneumonia have markedly elevated serum IL‐1β, IL‐6, IL‐8, IL‐10, IL‐17, TNF‐α, and IP‐10 levels at the initial phase of the illness indicating a cytokine storm following SARS‐CoV‐2 infection. Moreover, serum IL‐6, IL‐1β, and IP‐10 concentrations were independent predictors for severe COVID‐19 pneumonia.

TA allele of rs2070673 in the CYP2E1 gene is associated with lobular inflammation and nonalcoholic steatohepatitis in patients with biopsy-proven nonalcoholic fatty liver disease.

Cytochrome P450 2E1 (CYP2E1) plays a role in lipid metabolism, and by increasing hepatic oxidative stress and inflammation, the upregulation of CYP2E1 is involved in development of nonalcoholic steatohepatitis (NASH). We aimed to explore the relationship between CYP2E1-333A>T (rs2070673) and the histological severity of nonalcoholic fatty liver disease (NAFLD). We studied 438 patients with biopsy-proven NAFLD. NASH was defined as NAFLD Activity Score≥5 with existence of steatosis, ballooning, and lobular inflammation. CYP2E1-333A>T (rs2070673) was genotyped by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Serum cytokines related to inflammation were measured by the Bio-plex 200 system to investigate possible mediating factors involved in the process. The TA genotype of rs2070673 had a higher prevalence of moderate/severe lobular inflammation (27.6% vs 20.3% vs 13.3%, P<0.01) and NASH (55.7% vs 42.4% vs 40.5%, P<0.01) compared with the AA and TT genotypes, respectively. In multivariable regression modeling, the heterozygote state TA was associated with moderate/severe lobular inflammation (adjusted odds ratio: 2.31, 95% confidence interval 1.41-3.78, P<0.01) or NASH (adjusted odds ratio: 1.82, 95% confidence interval 1.22-2.69, P<0.01), independently of age, sex, common metabolic risk factors, and presence of liver fibrosis. Compared with no-NASH, NASH patients had significantly higher levels of serum interleukin-1 receptor antagonist, interleukin-18, and interferon-inducible protein-10 (IP-10), whereas only IP-10 was increased with the rs2070673 TA variant (P=0.01). Mediation analysis showed that IP-10 was responsible for ~60% of the association between the rs2070672 and NASH. The TA allele of rs2070673 is strongly associated with lobular inflammation and NASH, and this effect appears to be largely mediated by serum IP-10 levels.

The presence of IFL3/4 rs12979860 C allele influences the invitro IP-10 production by mononuclear cells from patients with systemic lupus erythematosus.

To explore whether the IFNL3/4 rs12979860 genotype may influence serum levels or production of interferon-inducible protein-10 (IP-10) by peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE). Sixty-six patients with SLE and 22 healthy blood donors (controls) were included. The IFNL3/4 rs12979860 polymorphism was genotyped by real-time polymerase chain reaction. IP-10 levels in sera supernatants of IFNα stimulated peripheral blood mononuclear cells were measured by enzime-linked immunosorbent assay. Allelic frequencies were CC (29%), CT (52%) and TT (20%) in SLE, and CC (32%), CT (41%) and TT (27%) in healthy controls. Median serum IP-10 levels were higher in SLE patients than in controls (190.8 versus 118.1 pg/ml; p < 0.001), particularly in those with high disease activity (278.5 versus 177.2 pg/ml; p = 0.037). However, serum IP-10 levels were not influenced by IFNL3/4 genotypes. Higher IP-10 production by peripheral blood mononuclear cells was found in both SLE patients (median 519.3 versus 207.6 pg/ml; p = 0.012) and controls (median 454.0 versus 201.7 pg/ml; p = 0.034) carrying the IFNL3/4 C allele compared with carriers of the T allele. Although IFNL3/4 rs12979860 allele C does not appear to influence serum IP-10 levels in SLE, it plays an important role in the production of IP-10 by peripheral blood mononuclear cells after IFNα stimulation.

Interferon-Inducible Protein 10 and Disease Activity in Systemic Lupus Erythematosus and Lupus Nephritis: A Systematic Review and Meta-Analysis.

There is increasing evidence of a correlation between interferon-inducible protein 10 (IP-10) and disease activity of systemic lupus erythematosus (SLE) and lupus nephritis (LN). We conducted a comprehensive search on IP-10 using MEDLINE, Scopus, and Cochrane electronic databases from the beginning to the end of December 2017. All studies that compared serum and/or urine IP-10 between active SLE/LN patients and any control groups were identified and included in this systematic review and meta-analysis. The mean difference (MD) of IP-10 level among active SLE and LN patients, as well as the correlation of IP-10 with disease activity, were meta-analyzed using a random-effects model. From 23 eligible studies, 15 provided adequate data for meta-analysis. Serum IP-10 was significantly elevated in patients with active SLE compared to non-active SLE patients (MD 356.5 pg/mL, 95% CI 59.6 to 653.4, p = 0.019). On the other hand, the levels of serum IP-10 was not different between active LN and non-active LN. However, serum IP-10 was positively correlated with disease activity like SLE disease activity index (SLEDAI) (pooled r = 0.29, 95% CI 0.22 to 0.35, p < 0.001). Furthermore, urine IP-10 tended to be higher in patients with active LN compared to non-active LN patients but this did not reach statistical significance (MD 3.47 pg/mgCr × 100, 95% CI −0.18 to 7.12, p = 0.06). Nevertheless, urine IP-10 was positively correlated with renal SLEDAI (pooled r = 0.29, 95% CI 0.05 to 0.50, p = 0.019). In conclusion, serum and urine IP-10 levels may be useful in monitoring the disease activity of SLE and LN. Serum IP-10 was correlated with systemic disease whereas urine IP-10 was a useful biomarker for detecting active LN.

Soluble TNF-R1, VEGF and other cytokines as markers of disease activity in systemic lupus erythematosus and lupus nephritis.

Current non-invasive methods of assessing disease activity in systemic lupus erythematosus (SLE) are of limited sensitivity and specificity. Testing includes acute phase markers, autoantibodies and complement levels. Although measurements of dsDNA antibodies and complement C3/C4 levels are routine, they remain of limited value. Improved blood and urine markers may help in early detection of flare, distinction between flare and chronic damage, and monitoring response to therapy. A total of 87 patients with SLE were tested for the following cytokines in serum and urine: monocyte chemoattractant protein 1 (MCP-1), regulated upon activation, normal T cell expressed and secreted (RANTES), soluble tumour necrosis factor receptor 1 (sTNF-R1), interferon-inducible protein 10 (IP-10), monocyte inhibitory protein 1α (MIP-1α) and vascular endothelial growth factor (VEGF). Patients attending the Lupus Unit at St Thomas' Hospital, London, UK were divided into active lupus nephritis (LN), inactive LN and non-renal SLE groups based on their renal pathology and SLE disease activity index (SLEDAI). Cytokine testing was performed using the FIDIS multiplex bead assay. The mean level of serum sTNF-R1 was higher in the active LN group compared with both inactive LN and non-renal SLE groups ( p < 0.001). For urine measurements there were significant differences between active LN and non-renal SLE for VEGF ( p = 0.016), after statistical correction for multiple testing. Both urinary and serum sTNF-R1 and IP-10 levels correlated with SLEDAI scores ( p < 0.001), while serum VEGF correlated weakly with SLEDAI ( p = 0.025). The optimum combination for differentiating active from inactive LN patients was serum VEGF, sTNF-R1, MCP-1 and glomerular filtration rate plus urinary sTNF-R1 and protein-creatinine ratio. These results indicate that for active LN, sTNF-R1 could be a useful serum cytokine marker, with potential for VEGF in the urine. This study has confirmed the ability of the multiplex bead technique to detect cytokines in a good analytical range, including very low and high levels, in both serum and urine. Combining serum and urine markers provided additional sensitivity in distinguishing active from inactive LN.

Serum interferon-inducible protein 10 levels predict hepatitis B s antigen seroclearance in patients with chronic hepatitis B.

Hepatitis B s antigen (HBsAg) seroclearance is regarded as the optimal virological end-point. To investigate the dynamic changes in serum cytokine levels around the time of HBsAg seroclearance. This was a case-control study. Consecutive patients with chronic hepatitis B (CHB) who lost HBsAg were matched with those remained positive for HBsAg with same age, gender, HBeAg status and presence of cirrhosis in 1:2 ratio. Relevant serum cytokines [interleukin (IL)-2, IL-3, IL-4, IL-7, IL-9, IL-10, IL-12, IL-15, IL-21 interferon-γ, tumour necrosis factor-α (TNF-α), granulocyte macrophage colony-stimulating factor (GM-CSF) and interferon-inducible protein 10 (IP-10)] were assayed at the time (Year 0) and 3 years before (Year -3) HBsAg seroclearance. Seventy-one and 142 CHB patients who did and did not achieve HBsAg seroclearance were included. Mean age was 48 ± 11 years; 76% were male, 20% had positive HBeAg, 99 (46%) patients received anti-viral therapy, and mean baseline HBV DNA was 3.78 ± 2.28 log IU/mL vs. 4.36 ± 2.13 log IU/mL respectively (P = 0.05). In those who achieved HBsAg seroclearance, serum IL-15 and GM-CSF levels decreased significantly from Year -3 to Year 0 (P = 0.017 and 0.05 respectively). When compared to controls, only serum IP-10 level was significantly lower at Year 0 than at Year -3 in patients with HBsAg seroclearance. Lower serum IP-10 level at Year 0 was the only factor associated with HBsAg seroclearance. There was no correlation between serum IP-10 and HBsAg levels around the time of HBsAg seroclearance. Lower serum IP-10 level at Year 0 was the only factor associated with HBsAg seroclearance.

Serum HBsAg kinetics and usefulness of interferon-inducible protein 10 serum in HBeAg-negative chronic hepatitis B patients treated with tenofovir disoproxil fumarate.

The kinetics of serum HBsAg and interferon-inducible protein 10 (IP10) levels in patients with chronic hepatitis B infection treated with tenofovir are unclear. We evaluated the changes of HBsAg levels and the predictability of IP10 for HBsAg decline in 160 HBeAg-negative patients receiving tenofovir for ≥12months. Serum samples taken before and at 6, 12, 24, 36 and 48months after tenofovir were tested for HBsAg levels. In 104 patients, serum samples before tenofovir were tested for IP10 levels. Compared to before tenofovir, HBsAg levels decreased by a median of 0.08, 0.11, 0.24, 0.33 and 0.38 log10 IU/mL at 6, 12, 24, 36 and 48months, respectively (P<0.001). HBsAg kinetics did not differ between nucleos(t)ide analogue(s) naive and experienced patients. The 12-, 24-, 36- and 48-month cumulative rates of ≥0.5 log10 HBsAg decline were 8%, 16%, 24% and 41% and of HBsAg ≤100IU/mL were 9%, 12%, 14% and 18%, respectively. The only factor associated with HBsAg ≤100IU/mL was lower HBsAg levels before tenofovir (P<0.001), while HBsAg decline ≥0.5 log10 was associated with higher IP10 levels (P=0.002) and particularly with IP10>350pg/mL (P<0.001). In conclusion, tenofovir decreases serum HBsAg levels in both nucleos(t)ide analogue(s) naive and experienced patients with HBeAg-negative chronic hepatitis B infection. After 4years of therapy, HBsAg ≤100IU/mL can be achieved in approximately 20% of patients, particularly in those with low baseline HBsAg levels. HBsAg decline is slow (≥0.5 log10 in 40% of patients after 4years) and is associated only with higher baseline serum IP10 levels.

Changes of HBsAg and interferon-inducible protein 10 serum levels in naive HBeAg-negative chronic hepatitis B patients under 4-year entecavir therapy

Serum HBsAg levels might represent an important predictor of sustained off-treatment response in HBeAg-negative chronic hepatitis B (CHB). We evaluated the changes of HBsAg and interferon-inducible protein 10 (IP10) serum levels in HBeAg-negative CHB patients treated with entecavir. 114 patients received entecavir for a median of 4.3 years. HBsAg levels were determined at baseline, 6 and 12 months and every year thereafter until year-4. IP10 levels were measured at baseline and annually until year-4 in 76 patients. Virological remission rates were high (year-1: 94%, after year-2: 97-98%). Compared to baseline, HBsAg levels decreased by a median of 0.03, 0.13, 0.17, 0.22, and 0.32 log₁₀ IU/ml at 6 months and 1, 2, 3, and 4 years, respectively (p≤0.001 for all comparisons). The proportions of patients with HBsAg decline of ≥0.5 or ≥1 log₁₀ IU/ml were 9% or 6% at year-1 and 21% or 10% at the last visit. Median IP10 levels (pg/ml) did not change from baseline to year-1 or -2 (245 vs. 229 or 251), but increased at year-3 and -4 (275 and 323, p<0.030). HBsAg drop ≥0.5 log₁₀ was associated with baseline IP10 or IP10 >350 pg/ml (p≤0.002). HBsAg loss occurred in 4/114 (3.5%) patients or in 1/2, 3/21, and 0/91 patients with baseline HBsAg <100, 100-1000 and >1000 IU/ml, respectively (p<0.001). In HBeAg-negative CHB patients, 4-year entecavir therapy decreases serum HBsAg levels, but the rate of decline is rather slow. Serum IP10 levels represent a promising predictor of HBsAg decline in this setting.

Hepatitis B Surface Antigen (Hbsag) Decrease and Serum Interferon-Inducible Protein-10 Levels as Predictive Markers for Hbsag Loss during Treatment with Nucleoside/Nucleotide Analogues

Hepatitis B surface antigen (HBsAg) loss is the ultimate goal of antiviral therapy and its prediction may be important for treatment individualization. Quantitative HBsAg (qHBsAg) has been shown to predict response to interferon-α, but few studies have analysed qHBsAg during treatment with nucleoside/nucleotide analogues (NAs). Serum interferon-inducible protein-10 (IP-10) has been associated with treatment response in hepatitis C, but data in chronic hepatitis B are lacking. Here, we aimed to investigate potential factors predictive for HBsAg loss. HBsAg was quantified at multiple time points in 126 patients with chronic HBV infection; 95 received NA treatment for 6-107 months. At an early time point (first 6 months of therapy) and late time point after virological response (VR; HBV DNA<100 IU/ml), we distinguished three patterns of HBsAg decrease: strong decrease (>0.5 log(10)), moderate decrease (10% to 0.5 log(10)) and no decrease (<10%). In addition to conventional biochemical and virological parameters, we analysed serum IP-10 levels in 55 patients. Early and late HBsAg kinetics did not correlate. Overall, 42% of patients with a strong HBsAg decrease 2 years after VR cleared HBsAg. Importantly, no patient without a late HBsAg decrease >0.5 log(10) cleared HBsAg. By contrast, early HBsAg decrease after 6 months of NA therapy was not associated with HBsAg loss. Baseline serum IP-10 levels were associated with late but not early HBsAg kinetics and were highest in patients with HBsAg loss. Monitoring qHBsAg after successful HBV DNA suppression might be useful to identify patients who clear HBsAg, implicating finite NA treatment. The role of IP-10 as predictive marker for HBsAg loss should be further evaluated.

Serum IL-R1a and IP-10 Cytokine/chemokine Profiling Differences in Immune Responders and Non-responders to Combination Radiation / Immunotherapy for Soft Tissue Sarcoma

Background: Patients with large, high-grade soft tissue sarcomas (STS) have a >50% risk of developing systemic disease following external beam radiation (EBRT) and surgery. Combination of EBRT with experimental intratumoral injection of dendritic cells (DC) in addition to surgical extirpation adds innovative immunotherapy to standard treatment. To evaluate a possible link between immune responses to sarcoma tumor-associated antigens (TAA) and serum cytokine/chemokine (CC) levels in responders and non-responders patients to EBRT / DC. Prospective phase I/II trial of 18 patients with clinical stage T2N0M0 high grade STS of the extremity / trunk / chest wall completing pre-operative EBRT with DC. The serum levels of 27 CC (IL-1Ra, IP-10, G-CSF, GM-CSF, IL-1β, IL-2, IL-4, IL-5, IL-10, IL-13, IL-15, IL-17, MIP-1α, Rantes, TNF-α, bFGF, eotaxin, IFN-γ, IL-12 (p70), IL-6, IL-7, IL-8, IL-9, MCP-1, MIP-1β, PDGF, and VEGF) were profiled in all patients before, during (at week 4), and after EBRT/DC therapy prior to surgical extirpation (at week 8-10) using Bio-Rad Pro Human Cytokine Kits. Immune responders were defined as patients induced to produce significant anti-autologous tumor cell immune responses determined via ELISPOT assays on patients' peripheral blood mononuclear cells; CC levels of the10 immune responders were compared to the 8 non-responders. Significant differences between responders and non-responders were found in profiling two CC: IL-1 receptor antagonist (IL-1Ra), and interferon-inducible protein 10 (IP-10). Before EBRT with DC treatment, none of the mean serum CC levels were different between responder and non-responder patients. Non-responders had significantly lower levels of IL-1Ra than responders at 4 weeks (p = 0.007) and 8-10 weeks (p = 0.029). Non-responders had significantly higher levels of IP-10 than responders at 4 weeks (p = 0.036) and 8-10 weeks (p = 0.01). In addition, with clinical follow-up >1 year available on 14 of 18 patients, only 1/7 immune responder patients developed progressive disease, whereas 4/7 non-responder patients developed progressive disease. These data suggest significant profiling differences in serum IL-R1a and IP-10 for immune responders and non-responders treated with combination of EBRT with intratumoral injection of DC. Next generation trials will further evaluate immune monitoring of these molecules and their predictive value.

Production of Interferon-Inducible Protein-10 and Its Role as an Autocrine Invasion Factor in Nasal Natural Killer/T-Cell Lymphoma Cells

Nasal natural killer (NK)/T-cell lymphoma is associated with Epstein-Barr virus and has poor prognosis because of local invasion and/or multiple dissemination. Recently, the role of chemokines/chemokine receptors in tumor proliferation and invasion has been shown. In this study, we examined whether the specific chemokines were related to the tumor behaviors in nasal NK/T-cell lymphoma. A chemokine protein array was used to examine specific chemokines produced by SNK-6 and SNT-8 (Epstein-Barr virus-positive nasal NK/T-cell lymphoma lines). The expression of interferon gamma-inducible protein 10 (IP-10) and the IP-10 receptor CXCR3 was investigated by ELISA and flow cytometry. Cell growth and invasion were assessed by the MTT and Matrigel invasion assays, respectively. Immunohistologic staining and ELISA were used to examine IP-10 expression in biopsies and sera from patients, respectively. IP-10 was specifically produced by SNK-6 and SNT-8. Moreover, CXCR3 was expressed on the NK cell lines. Functionally, IP-10 did not affect cell proliferation but enhanced cell invasion. In biopsy samples, IP-10 and CXCR3 expressions were detected in the lymphoma cells. Serum IP-10 levels in the patients were much higher than those of healthy controls and the levels were decreased during the complete remission phase after treatments. These results suggest that IP-10 may play an important role in cell invasion in nasal NK/T-cell lymphoma through an autocrine mechanism.

Enhanced expression of interferon-inducible protein-10 correlates with disease activity and clinical manifestations in systemic lupus erythematosus

Our objective was to investigate the serum levels of interferon-inducible protein-10 (IP-10) in systemic lupus erythematosus (SLE) and their correlation with disease activity and organ manifestations. Serum IP-10 levels were assessed in 464 SLE patients and 50 healthy donors. Disease activity was assessed by the revised SLE Activity Measure, and the concomitant active organ manifestations, anti-ds DNA antibody titres, complement levels and erythrocyte sedimentation rates recorded. Peripheral blood mononuclear cell (PBMC) synthesis of IP-10 in SLE patients and controls was determined by in vitro cultures stimulated with mitogen or lipopolysaccharide. Elevated serum IP-10 levels were observed in SLE patients, which were significantly higher in the presence of active haematological and mucocutaneous manifestations. SLE PBMCs exhibited enhanced spontaneous IP-10 production in vitro. Serial IP-10 levels correlated with longitudinal change in SLE activity, even at low levels where anti-dsDNA antibody and complement levels remain unchanged. These data demonstrate that IP-10 levels are increased in SLE and serum IP-10 may represent a more sensitive marker for monitoring disease activity than standard serological tests.

Activation of Innate Immunity in Healthy Macaca mulatta Macaques by a Single Subcutaneous Dose of GMP CpG 7909: Safety Data and Interferon-Inducible Protein-10 Kinetics for Humans and Macaques

Following a demonstration that mouse-optimized cytosine-guanosine dinucleotide (CpG) oligodeoxynucleotides stimulated innate immune protection against intracellular pathogens, we tested the ability of CpG 7909, a primate-optimized Toll-like receptor 9 (TLR9) agonist, to stimulate rhesus macaques to produce interferon-inducible protein-10 (IP-10), a biomarker of immune activation. This study was performed prior to a similar trial with humans in order to facilitate the development of CpG 7909 as an immunomodulator for biodefense. A single subcutaneous dose of clinical-grade CpG 7909 was given to four groups of healthy adult rhesus macaques (0-mg dose [n = 5], 0.75-mg dose [n = 9], 1.5-mg dose [n = 9], and 3.0-mg dose [n = 9]). Directed physical examination findings, clinical laboratory values, and serum IP-10 concentrations were collected at scheduled intervals for 28 days. All three dose levels of CpG 7909 were safe and not associated with significant clinical or laboratory abnormality. The time to peak serum IP-10 concentration was 1.0 days at the 0.75-mg dose and 0.5 days at the 1.5- and 3.0-mg doses. A dose-dependent response was observed for the magnitude and duration of IP-10 concentrations, which remained significantly above baseline for 3 days for the 3.0-mg and 1.5-mg dose groups but above baseline for only 2 days for the 0.75-mg dose group. There were no nonresponders to CpG 7909. These rhesus macaque safety and IP-10 response data closely parallel a subsequent phase 1 human study of subcutaneously administered CpG 7909. A single dose of clinical-grade CpG 7909 induced a rapid, sustained IP-10 response, a biomarker for activation of the innate immune system. Given the similar susceptibilities of humans and rhesus macaques to infectious diseases, the rhesus macaque appears to be a suitable model to evaluate the potential of CpG 7909-mediated innate immune activation to protect humans against pathogens.

T-cell function in anti-GAD65 +diabetes with residual β-cell function

We have recently reported that in patients with anti-glutamic acid decarboxylase (GAD) 65 +diabetes with residual β-cell function, most with a ‘high-titer’ (>10 U/ml) required insulin within 5 years, whereas most with a ‘low-titer’ (1.3–9.9 U/ml) did not need insulin for over 15–20 years after the onset. We therefore examined T-cell function to evaluate the difference between the high-titer and low-titer groups. Interleukin (IL)-10 production upon polyclonal activation was significantly lower in the high-titer group than in the low-titer group. The serum level of interferon-inducible protein-10 (IP-10) was higher in the high-titer than the low-titer group. Although GAD65-reactive CD4 +cells in the periphery were detected in both groups, a significant positive correlation between serum IP-10 level and the number of GAD65-reactive CD4 +cells was observed only in the high-titer group. Therefore, it has been speculated that the co-existence of GAD65-reactive IFN-γ-producing CD4 +cells and a high serum IP-10 level may be important for rapid disease progression as seen in the high-titer group. Based upon these results, T-cell function is considered to be different between the high-titer and low-titer groups in anti-GAD65 +diabetes with residual β-cell function, supporting our previous findings regarding the clinical outcome of insulin-dependence in the two groups.

Elevated serum IP-10 levels observed in type 1 diabetes.

Although most patients with type 1 diabetes are considered to have T-cell-mediated autoimmune disease, a method of measuring of pancreatic beta-cell-specific T-cell function in cases of type 1 diabetes has yet to be established. Here, we focused on interferon-inducible protein-10 (IP-10), a chemokine that promotes the migration of activated T-helper 1 (Th1) cells and measured serum IP-10 levels in patients with human type 1 diabetes, which is regarded as a Th1-mediated disease. Serum samples were obtained from diabetic patients, and the levels of autoantibodies (GAD and insulinoma-associated protein-2 [IA-2]) and IP-10 were measured. Diabetic patients positive for either or both of the autoantibodies were classified as Ab+ type 1, and those negative for both were classified as Ab type 1. To evaluate islet antigen-specific responses, peripheral blood from patients stimulated with or without GAD was used, and intracellular cytokine staining for flowcytometry was performed. The Ab+ and Ab- type 1 groups both showed a significantly higher serum IP-10 level than the healthy subjects (P < 0.001 and P < 0.05, respectively), and the IP-10 level in the recent-onset Ab+ subgroup was significantly higher than that in the established (longstanding) Ab+ subgroup (P < 0.002). Furthermore, there was a significant positive correlation between the serum IP-10 level and the number of GAD-reactive gamma-interferon-producing CD4+ cells in the Ab+ type 1 group (P < 0.007). Our findings demonstrate that measurement of serum IP-10 concentrations is useful in patients with type 1 diabetes.