Efficacy and safety of PD-1 monoclonal antibody combined with interferon-alpha 1b and anlotinib hydrochloride as the second-line therapy in patients with unresectable advanced melanoma: A retrospective study.

BACKGROUND: Immune-checkpoint inhibitors are now used more commonly in combination than monotherapy as the first-line choice in patients with unresectable advanced melanoma. Nevertheless, for cases that progressed after the initial combination therapy, the subsequent regimen option can be very difficult. Herein, we reported the efficacy and safety of a triple combination regimen in Chinese unresectable advanced melanoma patients who had poor responses to the first-line immune therapy. METHODS: We reviewed the clinical profiles of patients diagnosed with stage IIIC-IV melanoma between June 1, 2020, and September 30, 2023. The patients who failed the prior immune therapies and received anti-PD-1 mono antibody plus interferon(IFN)-alpha 1b and anlotinib hydrochloride as the second-line therapy were enrolled in the retrospective analysis. Additionally, we examined the exhaustion of T-cells using mIHC staining in available tumor samples. RESULTS: Fifty-five patients were included in this study. The median follow-up period was 13.6 months. The objective response rate evaluated by the investigators was 9.1%(1CR, 4PR). The disease control rate was 47.3%. The median overall survival was 17.6 months, and the median progression-free survival was 2.8 months. The adverse events rate of any grade was 100%. Grade 3 or 4 irAEs were observed in 29.1% of cases. Multiplex immunohistochemical staining revealed an increased trend of TIM3 expression on tumor-infiltrating T cells in patients without objective response. CONCLUSION: PD-1 monoclonal antibody plus interferon-alpha 1b plus anlotinib showed acceptable tolerability and anticancer benefits in Chinese metastatic melanoma patients as a second-line therapy.

Type I interferon signaling induces melanoma cell-intrinsic PD-1 and its inhibition antagonizes immune checkpoint blockade.

Programmed cell death 1 (PD-1) is a premier cancer drug target for immune checkpoint blockade (ICB). Because PD-1 receptor inhibition activates tumor-specific T-cell immunity, research has predominantly focused on T-cell-PD-1 expression and its immunobiology. In contrast, cancer cell-intrinsic PD-1 functional regulation is not well understood. Here, we demonstrate induction of PD-1 in melanoma cells via type I interferon receptor (IFNAR) signaling and reversal of ICB efficacy through IFNAR pathway inhibition. Treatment of melanoma cells with IFN-α or IFN-ß triggers IFNAR-mediated Janus kinase-signal transducer and activator of transcription (JAK/STAT) signaling, increases chromatin accessibility and resultant STAT1/2 and IFN regulatory factor 9 (IRF9) binding within a PD-1 gene enhancer, and leads to PD-1 induction. IFNAR1 or JAK/STAT inhibition suppresses melanoma-PD-1 expression and disrupts ICB efficacy in preclinical models. Our results uncover type I IFN-dependent regulation of cancer cell-PD-1 and provide mechanistic insight into the potential unintended ICB-neutralizing effects of widely used IFNAR1 and JAK inhibitors.

The evolving landscape of polycythemia vera therapies.

INTRODUCTION: The treatment landscape of polycythemia vera (PV) has seen major advancements within the last decade including approval of ruxolitinib in the second line setting after hydroxyurea, ropegylated interferon-α2b, and advanced clinical development of a novel class of agents called hepcidin mimetics. AREAS COVERED: We provide a comprehensive review of the evidence discussing the risk stratification, treatment indications, role and limitations of phlebotomy only approach and pivotal trials covering nuances related to the use of interferon-α (IFN-α), ruxolitinib, hepcidin mimetics, and upcoming investigational agents including HDAC and LSD1 inhibitors. EXPERT OPINION: The research paradigm in PV is slowly shifting from the sole focus on hematocrit control and moving toward disease modification. The discovery of hepcidin mimetics has come as a breakthrough in restoring iron homeostasis, achieving phlebotomy-independence and may lead to improved thrombosis-free survival with stricter hematocrit control. On the other hand, emerging data with IFN- α and ruxolitinib as well as combination of the two agents suggests the potential for achieving molecular remission in a subset of PV patients and long-term follow-up is awaited to validate the correlation of molecular responses with clinically relevant outcomes of progression-free and thrombosis-free survival.

Biochemical implication of acetylcholine, histamine, IL-18, and interferon-alpha as diagnostic biomarkers in hepatitis C virus, coronavirus disease 2019, and dual hepatitis C virus-coronavirus disease 2019 patients.

Globally, hepatitis C virus (HCV) and coronavirus disease 2019 (COVID-19) are the most common causes of death due to the lack of early predictive and diagnostic tools. Therefore, research for a new biomarker is crucial. Inflammatory biomarkers are critical central players in the pathogenesis of viral infections. IL-18, produced by macrophages in early viral infections, triggers inflammatory biomarkers and interferon production, crucial for viral host defense. Finding out IL-18 function can help understand COVID-19 pathophysiology and predict disease prognosis. Histamine and its receptors regulate allergic lung responses, with H1 receptor inhibition potentially reducing inflammation in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. angiotensin-converting enzyme 2 (ACE-2) receptors on cholangiocytes suggest liver involvement in SARS-CoV-2 infection. The current study presents the potential impact of circulating acetylcholine, histamine, IL-18, and interferon-Alpha as diagnostic tools in HCV, COVID-19, and dual HCV-COVID-19 pathogenesis. The current study was a prospective cross-section conducted on 188 participants classified into the following four groups: Group 1 COVID-19 (n = 47), Group 2 HCV (n = 47), and Group 3 HCV-COVID-19 patients (n = 47), besides the healthy control Group 4 (n = 47). The levels of acetylcholine, histamine, IL-18, and interferon-alpha were assayed using the ELISA method. Liver and kidney functions within all groups showed a marked alteration compared to the healthy control group. Our statistical analysis found that individuals with dual infection with HCV-COVID-19 had high ferritin levels compared to other biomarkers while those with COVID-19 infection had high levels of D-Dimer. The histamine, acetylcholine, and IL-18 biomarkers in both COVID-19 and dual HCV-COVID-19 groups have shown discriminatory power, making them potential diagnostic tests for infection. These three biomarkers showed satisfactory performance in identifying HCV infection. The IFN-Alpha test performed well in the HCV-COVID-19 group and was fair in the COVID-19 group, but it had little discriminative value in the HCV group. Moreover, our findings highlighted the pivotal role of acetylcholine, histamine, IL-18, and interferon-Alpha in HCV, COVID-19, and dual HCV-COVID-19 infection. Circulating levels of acetylcholine, histamine, IL-18, and interferon-Alpha can be potential early indicators for HCV, COVID-19, and dual HCV-COVID-19 infection. We acknowledge that further large multicenter experimental studies are needed to further investigate the role biomarkers play in influencing the likelihood of infection to confirm and extend our observations and to better understand and ultimately prevent or treat these diseases.

Establishment of a protocol for rapidly expanding Epstein-Barr-virus-specific cytotoxic T cells with enhanced cytotoxicity.

BACKGROUND: Lytic Epstein-Barr virus (EBV) infection plays a major role in the pathogenesis of nasopharyngeal carcinoma (NPC). For patients with recurrent or metastatic NPC and resistant to conventional therapies, adoptive cell therapy using EBV-specific cytotoxic T cells (EBV-CTLs) is a promising option. However, the long production period (around 3 to 4 weeks) and low EBV-CTL purity (approximately 40% of total CD8 T cells) in the cell product limits the application of EBV-CTLs in clinics. Thus, this study aimed to establish a protocol for the rapid production of EBV-CTLs. METHODS: By culturing peripheral blood mononuclear cells (PBMCs) from EBV-seropositive donors with EBV-specific peptides and interleukin (IL)-2, IL-15, and interferon α (IFN-α) for 9 days, we identified that IL-15 can enhance IL-2-mediated CTL activation and significantly increase the yield of CTLs. RESULTS: When IFN-α was used in IL-2/IL-15-mediated CTL production from days 0 to 6, the productivity of EBV-CTLs and EBV-specific cytotoxicity significantly were reinforced relative to EBV-CTLs from IL-2/IL-15 treatment. Additionally, IFN-α-induced production improvement of virus-specific CTLs was not only the case for EBV-CTLs but also for cytomegalovirus-specific CTLs. CONCLUSION: We established a novel protocol to rapidly expand highly pure EBV-CTLs from PBMCs, which can produce EBV-CTLs in 9 days and does not require feeder cells during cultivation.

Results of a phase I/IIa trial of SV-BR-1-GM inoculation with low-dose cyclophosphamide and interferon alpha (Bria-IMT) in metastatic breast cancer.

This Phase I/IIa open-label, single-arm clinical trial addressing advanced, refractory, metastatic breast cancer was conducted at six medical centers in the United States. We repeated inoculations with irradiated SV-BR-1-GM, a breast cancer cell line with antigen-presenting activity engineered to release granulocyte-macrophage colony-stimulating factor (GM-CSF), with pre-dose low-dose cyclophosphamide and post-dose local interferon alpha. Twenty-six patients were enrolled; 23 (88.5%) were inoculated, receiving a total of 79 inoculations. There were six Grade 4 and one Grade 5 adverse events noted (judged unrelated to SV-BR-1-GM). Disease control (stable disease [SD]) occurred in 8 of 16 evaluable patients; 4 showed objective regression of metastases, including 1 patient with near-complete regressions in 20 of 20 pulmonary lesions. All patients with regressions had human leukocyte antigen (HLA) matches with SV-BR-1-GM; non-responders were equally divided between matching and nonmatching (p = .01, Chi-squared), and having ≥2 HLA matches with SV-BR-1-GM (n = 6) correlated with clinical benefit. Delayed-type hypersensitivity (DTH) testing to candida antigen and SV-BR-1-GM generated positive responses (≥5 mm) in 11 (42.3%) and 13 (50%) patients, respectively. Quantifying peripheral circulating tumor cells (CTCs) and cancer-associated macrophage-like cells (CAMLs) showed that a drop in CAMLs was significantly correlated with an improvement in progression-free survival (PFS; 4.1 months vs. 1.8 months, p = .0058). Eight of 10 patients significantly upregulated programmed cell death ligand 1 (PD-L1) on CTCs/CAMLs with treatment (p = .0012). These observations support the safety of the Bria-IMT regimen, demonstrate clinical regressions, imply a role for HLA matching, and identify a possible value for monitoring CAMLs in peripheral blood.

A high functional cure rate was induced by pegylated interferon alpha-2b treatment in postpartum hepatitis B e antigen-negative women with chronic hepatitis B virus infection: an exploratory study.

Background and aims: Limited data have been reported on achieving functional cure using pegylated interferon (Peg-IFN) alpha-2b treatment for postpartum hepatitis B e antigen (HBeAg)-negative women with chronic hepatitis B virus (HBV) infection. This study was to assess the effectiveness and safety of Peg-IFN alpha-2b in HBV postpartum women without HBeAg and identify factors linked to the functional cure. Methods: A total of 150 HBeAg-negative postpartum women were retrospectively recruited.47 patients received Peg-IFN alpha-2b [Peg-IFN(+) group] and 103 patients did not [Peg-IFN(-) group]. Propensity score matching (PSM) was used to adjust the baseline imbalance between the two groups. The patients were followed for at least 48 weeks. The primary endpoints were hepatitis B surface antigen(HBsAg) loss and HBsAg seroconversion at 48 weeks. Logistic regression analysis was used to assess factors associated with HBsAg loss at 48 weeks. Results: At week 48,the HBsAg loss and seroconversion rate in Peg-IFN(+) group were 51.06%(24/47) and 40.43%(19/47), respectively. Even after PSM, Peg-IFN(+) group still showed higher HBsAg loss rate (50.00% vs 7.14%,p<0.001) and higher HBsAg seroconversion rate (38.10% vs 2.38%,p<0.001). Baseline HBsAg levels (Odds Ratio [OR]: 0.051, 95% Confidence Interval [CI]: 0.003-0.273, P=0.010), HBsAg at week 24 (OR:0.214, 95%CI:0.033-0.616, P=0.022), HBsAg decline at week 24 (OR:4.682, 95%CI: 1.624-30.198, P=0.022) and postpartum flare (OR:21.181, 95%CI:1.872-633.801, P=0.030) were significantly associated with HBsAg loss at week 48 after Peg-IFN alpha-2b therapy. Furthermore, the receiver operating characteristic curve (ROC) showed that the use of baseline HBsAg<182 IU/mL, HBsAg at week24 < 4 IU/mL and HBsAg decline at week24>12IU/mL were good predictors of HBsAg loss. No serious adverse events were reported. Conclusion: Peg-IFN alpha-2b treatment could achieve a high rate of HBsAg loss and seroconversion in HBeAg-negative postpartum women with reliable safety, particularly for patients experience postpartum flare and have low baseline HBsAg levels.

Functional cure induced by tenofovir alafenamide plus peginterferon-alpha-2b in young children with chronic hepatitis B: a case series study.

BACKGROUND AND AIMS: Data on the safety and effectiveness of tenofovir alafenamide (TAF) plus peginterferon-alpha (Peg-IFN-α) in children with chronic hepatitis B (CHB) are lacking. The current study aimed to present the characteristics of four pediatric CHB patients who obtained a functional cure by using TAF and Peg-IFN-α. METHODS: In this case series study initiated in May 2019, ten children who had no clinical symptoms or signs received response-guided (HBV DNA undetectable, hepatitis B e antigen [HBeAg] loss or seroconversion, and hepatitis B surface antigen [HBsAg] loss or seroconversion) and functional cure-targeted (HBsAg loss or seroconversion) TAF (25 mg/d, orally) plus Peg-IFN-α-2b (180 µg/1.73m2, subcutaneously, once weekly) in combination (9/10) or sequential (1/10) therapy. The safety and effectiveness of these treatments were monitored. RESULTS: As of April 2024, four out of ten children obtained a functional cure after a mean of 31.5 months of treatment, and the other six children are still undergoing treatment. These four cured children, aged 2, 4, 8, and 6 years, were all HBeAg-positive and had alanine aminotransferase levels of 80, 47, 114, and 40 U/L; HBV DNA levels of 71200000, 93000000, 8220, and 96700000 IU/mL; and HBsAg levels of 39442.8, 15431.2, 22, and 33013.1 IU/mL, respectively. During treatment, all the children (10/10) experienced mild or moderate adverse events, including flu-like symptoms, anorexia, fatigue, and cytopenia. Notably, growth retardation (8/10) was the most significant adverse event; and it occurred in three cured children (3/4) treated with combination therapy and was present to a low degree in the other cured child (1/4) treated with sequential therapy. Fortunately, all three cured children recovered to or exceeded the normal growth levels at 9 months posttreatment. CONCLUSIONS: TAF plus Peg-IFN-α-2b therapy is potentially safe and effective for pediatric CHB patients, which may provide important insights for future clinical practice and study designs targeting functional cures for children with CHB.

The efficacy of long-term psoralen plus ultraviolet A and low-dose interferon-a combination therapy in mycosis fungoides: A literature review.

BACKGROUND/PURPOSE: Interferon (IFN)-a is often used in combination with psoralen plus ultraviolet A (PUVA) in patients with mycosis fungoides (MF) refractory to skin-targeted therapies in early or advanced stages. The main objective is to evaluate the effectiveness of combined PUVA and low-dose IFN-α-2a therapy in patients with early- and advanced-stage MF. METHODS: Sixty-eight patients who received a combination of PUVA twice or thrice a week and INF-a 3 MU thrice a week for at least 3 months were reviewed retrospectively. The treatment response was evaluated as complete remission (CR), partial remission, stable disease, or progression. RESULTS: At the initiation, the majority of patients (66.2%) had early-stage disease. In 27.9% of cases, this was the initial treatment administered following the diagnosis of MF. The median duration of combination therapy was 11 months. Complete remission was achieved in 45.6% of the patients with an overall response rate of 60.3%. The mean duration of response was 5 months. Complete remission was statistically significantly higher in early-stage patients (p < .05). No statistically significant correlation was observed between CR and gender, histopathological features, or laboratory parameters. In patients with CR, 80% experienced relapse, significantly higher in early-stage patients (p < .05). However, there was no significant difference in disease-free survival between early and advanced stages (p > .05). CONCLUSIONS: The study results indicated that PUVA + low-dose INF-a combination therapy was more effective in the early stage than in the advanced stage. Additionally, there was a high relapse rate after the cessation of treatment in patients who achieved CR.

Plasma metabolome analysis for predicting antiviral treatment efficacy in chronic hepatitis B: diagnostic biomarkers and therapeutic insights.

The early and accurate identification of predictive biomarkers for antiviral treatment efficacy remains a significant clinical challenge, particularly in the management of chronic hepatitis B (CHB). This study aimed to assess whether the plasma metabolome could reliably predict the success of antiviral therapy in CHB patients. We conducted a retrospective analysis on 56 treatment-naive CHB patients at the First Affiliated Hospital of Zhejiang University from December 2013 to March 2016. Patients who underwent a 48-week treatment regimen of entecavir (ETV) and interferon-alpha (IFN-α) were randomly assigned to either a discovery cohort (n=29) or a validation cohort (n=27). Based on the outcome of the treatment, patients were classified as HBeAg seroconversion group (High responders, Hrp) or the non-remission group (Low responder, Lrp). Our methodology involved an untargeted analysis of the amine/phenol and carboxylic acid submetabolomes in the CHB patients under treatment, utilizing chemical isotope labeling (CIL) techniques with liquid chromatography-mass spectrometry (LC-MS). Several metabolites were identified as having significant diagnostic potential for distinguishing Hrp from Lrp, with areas under the receiver operating characteristic curve (AUC) exceeding those typical clinical indicators. Notably, four metabolites, namely 2-methyl-3-ketovaleric acid, 2-ketohexanoic acid, 6-oxo-1,4,5,6-tetrahydronicotinic acid, and α-ketoisovaleric acid, demonstrated exceptionally high sensitivity and specificity in both cohorts, nearing 100%. In contrast, the clinical indicators, including HBcAb, log(HBsAg), and HBeAb, demonstrated lower and inconsistent sensitivity and specificity between the discovery and validation cohorts. Using HBcAb as a marker, the sensitivity was 87.5% with 76.9% specificity in the discovery cohort; however, the sensitivity dropped to 46.7% with 91.7% specificity in the validation cohort. Using log(HBsAg), the sensitivity was 84.6% with 69.2% specificity in the discovery cohort, compared to 85.7% sensitivity and 83.3% specificity in the validation cohort. For HBeAb, the separation of Hrp and Lrp had a sensitivity of 87.5% with 69.2% specificity in the discovery cohort, while the validation cohort showed 86.7% sensitivity and 91.7% specificity.

Efficacy and safety outcomes in Japanese patients with low-risk polycythemia vera treated with ropeginterferon alfa-2b.

Polycythemia vera (PV) is a Philadelphia chromosome-negative myeloproliferative neoplasm characterized by clonal erythrocytosis. A phase 2 study reported that ropeginterferon alfa-2b is a well-tolerated and effective treatment for PV in Japanese patients. This post hoc analysis of the phase 2 data further evaluated outcomes in patients at low risk of thrombosis (low-risk PV). Among 20 patients with low-risk PV, 60.0% (12/20) and 85.0% (17/20) achieved < 45% hematocrit by weeks 24 and 52, respectively. The proportion of responders with complete hematologic response (CHR) was 60.0% (12/20) at week 52, and the median time to response was 11.9 months. The mean JAK2 V617F allele burden decreased from 75.8% at baseline to 53.7% at week 52. No patient experienced thrombosis or bleeding episodes. All patients experienced treatment-emergent adverse events (TEAEs) related to ropeginterferon alfa-2b, but no grade ≥ 3 TEAEs or deaths related to ropeginterferon alfa-2b occurred, and no new safety concerns arose. This analysis indicated that ropeginterferon alfa-2b may be an effective treatment option for Japanese patients with low-risk PV.

A De Novo Strategy To Improve Pharmacokinetics of Proteins from mRNA Therapeutics via Zwitterionic Polypeptide Fusion.

Achieving therapeutic efficacy in protein replacement therapies requires sustaining pharmacokinetic (PK) profiles, while maintaining the bioactivity of circulating proteins. This is often achieved via PEGylation in protein-based therapies, but it remains challenging for proteins produced in vivo in mRNA-based therapies due to the lack of a suitable post-translational modification method. To address this issue, we integrated a genetically encoded zwitterionic polypeptide, EKP, into mRNA constructs to enhance the PK properties of product proteins. Composed of alternating glutamic acid (E), lysine (K), and proline (P), EKP exhibits unique superhydrophilic properties and low immunogenicity. Our results demonstrate that EKP fusion significantly extends the circulation half-life of proteins expressed from mRNA while preserving their bioactivity using human interferon alpha and Neoleukin-2/15 as examples. This EKP fusion technology offers a new approach to overcoming the current limitations in mRNA therapeutics and has the potential to significantly advance the development of mRNA-based protein replacement therapy.

tRF-His-GTG-1 enhances NETs formation and interferon-α production in lupus by extracellular vesicle.

BACKGROUND: Hyperactive neutrophil extracellular traps (NETs) formation plays a crucial role in active severe systemic lupus erythematosus (SLE). However, what triggers the imbalance in dysregulated NETs formation in SLE is elusive. Transfer RNA-derived small RNAs (tsRNAs) are novel non-coding RNAs, which participate in various cellular processes. We explore the role of tsRNAs on NETs formation in SLE. METHODS: We analyzed the levels of NETs DNA and platelet-derived extracellular vesicles (pEVs) from 50 SLE patients and 20 healthy control subjects. The effects of pEVs on NETs formation were evaluated by using immunofluorescence assay and myeloperoxidase-DNA PicoGreen assay. The regulatory mechanism of pEVs on NETs formation and inflammatory cytokines production were investigated using an in vitro cell-based assay. RESULTS: Increased circulating NETs DNA and pEVs were shown in SLE patients and were associated with disease activity (P < 0.005). We demonstrated that SLE patient-derived immune complexes (ICs) induced platelet activation, followed by pEVs release. ICs-triggered NETs formation was significantly enhanced in the presence of pEVs through Toll-like receptor (TLR) 8 activation. Increased levels of tRF-His-GTG-1 in pEVs and neutrophils of SLE patients were associated with disease activity. tRF-His-GTG-1 interacted with TLR8 to prime p47phox phosphorylation in neutrophils, resulting in reactive oxygen species production and NETs formation. Additionally, tRF-His-GTG-1 modulated NF-κB and IRF7 activation in neutrophils upon TLR8 engagement, resulting IL-1ß, IL-8, and interferon-α upregulation, respectively. CONCLUSIONS: The level of tRF-His-GTG-1 was positively correlated with NETs formation in SLE patients; tRF-His-GTG-1 inhibitor could efficiently suppress ICs-triggered NETs formation/hyperactivation, which may become a potential therapeutic target.

Neutrophils and platelets are key members in the immunopathogenesis of SLE. EVs play a key role in intercellular communication. Abnormal NETs formation promotes vascular complications and organ damage in SLE patients. tsRNA is a novel regulatory small non-coding RNA and participates in diverse pathological processes. Herein, we showed that SLE patient-derived ICs activates platelets directly, followed by intracellular tRF-His-GTG-1 upregulation, which is loaded into pEVs. The pEV-carried tRF-His-GTG-1 could interact with TLR8 in neutrophils, followed by activation of the downstream signaling pathway, including p47phox-NOX2-ROS, which causes NETs enhancement, while IRF7 promotes the expression of IFN-α. The tRF-His-GTG-1 inhibitor could suppress efficiently SLE ICs-induced NETs formation and pEVs primed NETs enhancement. This study offers new molecular machinery to explain the association between the platelets-derived tsRNAs, pEVs, and hyperactive NETs formation in lupus. tRF-His-GTG-1 may serve as a potential therapeutic target and help to advance our understanding of tsRNAs in SLE pathogenesis.

Tumor-intrinsic IFNα and CXCL10 are critical for immunotherapeutic efficacy by recruiting and activating T lymphocytes in tumor microenvironment.

Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10-30% of patients with various cancers. Literature has demonstrated that a "hot tumor" which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a "cold tumor." This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8+ T cells to become "hot tumor." In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4+ T, and CD8+ T cell activation. Particularly, we found that CD8+ T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8+ T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8+ T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8+ T cells in the tumor microenvironment, exhibiting "hot tumor" characteristic of sensitizing αPD-L1 immunotherapies.

In vitro T cell responses to PD-1 blockade are reduced by IFN-α but do not predict therapy response in melanoma patients.

PD-1 blockade therapy has revolutionized melanoma treatment, but still not all patients benefit and pre-treatment identification of those patients is difficult. Increased expression of inflammatory markers such as interleukin (IL)-6 in blood of patients correlates with poor treatment response. We set out to study the effect of inflammatory cytokines on PD-1 blockade in vitro. For this, we studied the effect of IL-6 and type I interferon (IFN) in vitro on human T cells in a mixed leukocyte reaction (MLR) in the absence or presence of PD-1 blockade. While IL-6 reduced IFN-γ secretion by T cells in both the presence and absence of PD-1 blockade, IFN-α specifically reduced the IFN-γ secretion only in the presence of PD-1 blockade. IFN-α reduced T cell proliferation independent of PD-1 blockade and reduced the percentage of cells producing IFN-γ only in the presence of PD-1 blockade. Next we determined the type I IFN score in a cohort of 22 melanoma patients treated with nivolumab. In this cohort, we did not find a correlation between clinical response and type I IFN score, nor between clinical response and IFN-γ secretion in vitro in a MLR in the presence of PD-1 blockade. We conclude that IFN-α reduces the effectiveness of PD-1 blockade in vitro, but that in this cohort, type I IFN score in vivo, nor IFN-γ secretion in vitro in a MLR in the presence of PD-1 blockade correlated to decreased therapy responses in patients.

Loss of tolerance precedes triggering and lifelong persistence of pathogenic type I interferon autoantibodies.

Autoantibodies neutralizing type I interferons (IFN-Is) can underlie infection severity. Here, we trace the development of these autoantibodies at high-resolution using longitudinal samples from 1,876 well-treated individuals living with HIV over a 35-year period. Similar to general populations, ∼1.9% of individuals acquired anti-IFN-I autoantibodies as they aged (median onset ∼63 years). Once detected, anti-IFN-I autoantibodies persisted lifelong, and titers increased over decades. Individuals developed distinct neutralizing and non-neutralizing autoantibody repertoires at discrete times that selectively targeted combinations of IFNα, IFNß, and IFNω. Emergence of neutralizing anti-IFNα autoantibodies correlated with reduced baseline IFN-stimulated gene levels and was associated with subsequent susceptibility to severe COVID-19 several years later. Retrospective measurements revealed enrichment of pre-existing autoreactivity against other autoantigens in individuals who later developed anti-IFN-I autoantibodies, and there was evidence for prior viral infections or increased IFN at the time of anti-IFN-I autoantibody triggering. These analyses suggest that age-related loss of self-tolerance prior to IFN-I immune-triggering poses a risk of developing lifelong functional IFN-I deficiency.