Safety and efficacy of a single intra-articular injection of a novel enhanced protein solution (JTA-004) compared to hylan G-F 20 in symptomatic knee osteoarthritis: a randomized, double-blind, controlled phase II/III study.

BACKGROUND: New minimally invasive treatments are vital to delay joint replacement surgery in patients with knee osteoarthritis. This study was designed to select the most effective among three formulations of an enhanced protein solution containing clonidine, hyaluronic acid, and human plasma (JTA-004), and compare the safety and efficacy of intra-articular administration of the selected formulation with a reference treatment (hyaluronic acid) in symptomatic knee osteoarthritis patients. METHODS: In this two-stage, double-blind, phase II/III study conducted in 12 Belgian centers, 50-79-year-old patients with primary knee osteoarthritis were randomized (1:1:1:1) to receive one dose of one of three JTA-004 formulations (differing in clonidine concentration [50 or 100 µg/ml] and volume [2 or 4 ml]) or the reference treatment (hylan G-F 20). Patients were evaluated using Western Ontario McMaster Universities (WOMAC®) Scores and the Short-Form health survey up to 6 months post-injection (Month 6). Drug consumption and safety were evaluated. RESULTS: Among 164 treated patients, 147 completed the study. The JTA-004 formulation containing 200 µg clonidine and 20 mg hyaluronic acid in 2 ml (JTA-200/2) was selected based on interim results at Month 6. The difference in adjusted mean change in WOMAC Pain Subscale Score from baseline (JTA-200/2 minus reference group) at Month 6 was - 9.49 mm; statistical superiority of JTA-200/2 over the reference was not demonstrated. No statistically significant differences in adjusted mean changes from baseline between JTA-200/2 and reference groups were observed for Pain, Physical Function and Stiffness Subscales WOMAC Scores, Total WOMAC Score, and Well-being Score at any timepoint, although JTA-200/2 induced larger improvements in WOMAC Scores than the reference. Statistically significantly larger improvements in WOMAC Pain Subscale Scores for JTA-004 versus the reference were observed in post-hoc analyses on pooled data from all JTA-004 formulations at Month 6 (p = 0.030) and Month 3 (p = 0.014). All JTA-004 formulations had clinically acceptable safety profiles. CONCLUSIONS: This study provided preliminary evidence of the safety of intra-articular injection of JTA-004 in knee osteoarthritis patients. Phase III randomized controlled trials with larger sample sizes are needed to evaluate the efficacy of JTA-004 in knee osteoarthritis. TRIAL REGISTRATION: Clinicaltrials.gov/identifier NCT02740231; clinicaltrialsregister.eu/identifier 2015-002117-30. Retrospectively registered 13/4/2016.

Long-term antigen exposure irreversibly modifies metabolic requirements for T cell function.

Energy metabolism is essential for T cell function. However, how persistent antigenic stimulation affects T cell metabolism is unknown. Here, we report that long-term in vivo antigenic exposure induced a specific deficit in numerous metabolic enzymes. Accordingly, T cells exhibited low basal glycolytic flux and limited respiratory capacity. Strikingly, blockade of inhibitory receptor PD-1 stimulated the production of IFNγ in chronic T cells, but failed to shift their metabolism towards aerobic glycolysis, as observed in effector T cells. Instead, chronic T cells appeared to rely on oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) to produce ATP for IFNγ synthesis. Check-point blockade, however, increased mitochondrial production of superoxide and reduced viability and effector function. Thus, in the absence of a glycolytic switch, PD-1-mediated inhibition appears essential for limiting oxidative metabolism linked to effector function in chronic T cells, thereby promoting survival and functional fitness.

Metabolic programming in chronically stimulated T cells: Lessons from cancer and viral infections.

T-cell metabolism is central to the shaping of a successful immune response. However, there are pathological situations where T cells are rendered dysfunctional and incapable of eliminating infected or transformed cells. Here, we review the current knowledge on T-cell metabolism and how persistent antigenic stimulation, in the form of cancer and chronic viral infection, modifies both metabolic and functional pathways in T cells.

Micro-RNA-155-mediated control of heme oxygenase 1 (HO-1) is required for restoring adaptively tolerant CD4+ T-cell function in rodents.

T cells chronically stimulated by a persistent antigen often become dysfunctional and lose effector functions and proliferative capacity. To identify the importance of micro-RNA-155 (miR-155) in this phenomenon, we analyzed mouse miR-155-deficient CD4(+) T cells in a model where the chronic exposure to a systemic antigen led to T-cell functional unresponsiveness. We found that miR-155 was required for restoring function of T cells after programmed death receptor 1 blockade. Heme oxygenase 1 (HO-1) was identified as a specific target of miR-155 and inhibition of HO-1 activity restored the expansion and tissue migration capacity of miR-155(-/-) CD4(+) T cells. Moreover, miR-155-mediated control of HO-1 expression in CD4(+) T cells was shown to sustain in vivo antigen-specific expansion and IL-2 production. Thus, our data identify HO-1 regulation as a mechanism by which miR-155 promotes T-cell-driven inflammation.

Functional profile of S100A4-deficient T cells.

The protein S100A4 is best known for its significant role in promoting motility and invasive capacity of cancer cells. Since S100A4 expression has been reported also in T cells, we analyzed its potential role in T cell motility and inflammation. Using S100a4(+/Gfp) mice, we show here that S100A4 is exclusively expressed by memory T cells of CD4(+) or CD8(+) subpopulations, predominantly of the effector memory T cell subtype. However, the protein was not required for in vitro memory T cell migration toward gradients of the inflammatory chemokine CXCL10. Moreover, T cell memory response was normal in S100A4-deficient mice and lack of S100a4 gene expression did not induce any defect in promoting the development of protective immunity or inflammatory reactions leading to autoimmunity. Taken together, our results demonstrate that S100A4 activity is dispensable for T cell motility/migration and inflammatory potential.

High prevalence of high-risk human papillomavirus in palatine tonsils from healthy children and adults.

OBJECTIVE: The aim of this study was to determine the prevalence of human papillomavirus (HPV) in 80 tumor-free tonsils from healthy children and adults using a sensitive E6/E7 type-specific polymerase chain reaction (PCR). STUDY DESIGN: Cross-sectional study. SETTING: Ear, nose, and throat department, university hospital. SUBJECTS AND METHODS: Paraffin-embedded tissues from tumor-free tonsils (TFTs) were evaluated for HPV DNA using GP5+/6+ consensus PCR and subsequent genotyping using E6/E7 type-specific PCR for HPV types 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, and 68. The immunohistochemical expression of p16 and p53 was also assessed. RESULTS: In 80 TFTs, the authors identified 10 (12.5%) that tested positive for the following high-risk HPV types: HPV 16 (8 cases), 18 (1 case), and 31 (1 case). Twelve patients (15%) tested positive for HPV infection using the GP5+/GP6+ consensus primers but were negative using quantitative PCR. These patients were considered infected with low-risk HPV types. Fifty-eight TFTs (72.5%) tested negative for both GP5+/GP6+ and type-specific HPV PCR analysis (HPV negative). Among patients infected with HPV, the authors observed a slight increase in frequency with age. CONCLUSION: In TFTs, oncogenic and nononcogenic HPVs were present at a relatively high frequency in children and adults. The presence of high-risk HPV DNA in young children supports the horizontal transmission hypothesis and argues in favor of HPV vaccination at birth.