Insulin-like growth factors (IGFs), specifically IGF1 and IGF2, promote glucose metabolism, with their availability regulated by IGF-binding proteins (IGFBPs). We hypothesized that IGF1 and IGF2 levels, or their bioavailability, are reduced during type 1 diabetes development. Total serum IGF1, IGF2, and IGFBP1–7 levels were measured in an age-matched, cross-sectional cohort at varying stages of progression to type 1 diabetes. IGF1 and IGF2 levels were significantly lower in autoantibody (AAb)+ compared with AAb− relatives of subjects with type 1 diabetes. Most high-affinity IGFBPs were unchanged in individuals with pre–type 1 diabetes, suggesting that total IGF levels may reflect bioactivity. We also measured serum IGFs from a cohort of fasted subjects with type 1 diabetes. IGF1 levels significantly decreased with disease duration, in parallel with declining β-cell function. Additionally, plasma IGF levels were assessed in an AAb+ cohort monthly for a year. IGF1 and IGF2 showed longitudinal stability in single AAb+ subjects, but IGF1 levels decreased over time in subjects with multiple AAb and those who progressed to type 1 diabetes, particularly postdiagnosis. In sum, IGFs are dysregulated both before and after the clinical diagnosis of type 1 diabetes and may serve as novel biomarkers to improve disease prediction.

Recent studies, albeit controversial, have suggested that the incretin exendin-4 (Ex-4) is capable of inducing beta cell proliferation in vivo. Furthermore, this compound has been shown to enhance the ability of other agents (e.g., anti-CD3, antilymphocyte serum) to reverse type 1 diabetes (T1D) in NOD mice. However, the mechanisms underlying this beneficial action for disease reversal remain largely unclear. Herein, we tested the hypothesis that Ex-4 therapy may act as a stimulator of regulatory T cells (Tregs). We evaluated the effect of Ex-4 (Byetta; 0.2 microg/mouse/day for 30 days) treatment on the frequency and function of Tregs and changes in the cytokine profile of NOD mice with recently diagnosed T1D. In comparison to that of saline-treated control NOD mice, the frequency of Tregs was increased in Ex-4-treated mice. Suppression assays demonstrated a trend towards increased Treg suppression after administration of Ex-4, but were limited by small sample size. Lastly, Ex-4 treatment induced production of IL-10, indicating a possible shift towards a more Th2-like phenotype. Taken collectively, these data suggest that in addition to its potential effects on beta cell proliferation, Ex-4 may also act as a regulator of the immune response.

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Autoantibodies (AAb) against beta cell antigens are useful biomarkers for type 1 diabetes (T1D) prediction; however, staging of pre-T1D requires lengthy and invasive glucose tolerance testing. A need exists for additional serum biomarkers reflective of metabolic and immunologic dysregulation to test concurrently with AAb. The insulin-like growth factor (IGF) family, consisting of IGF1 and IGF2, has been shown to promote insulin action and possess immunoregulatory properties. Their activity is regulated by at least seven IGF binding proteins (IGFBPs). We hypothesized that IGF1 and IGF2 levels or bioavailability are reduced during T1D development. Total serum IGF1, IGF2, and IGFBP1-7 levels were measured in an age-matched (12.0 ± 3.7 years), cross-sectional cohort of AAb negative (AAb-) controls (CTRL) (n=74); AAb- first-degree relatives (AAb- FDR, n=55); FDR positive (AAb+ FDR) for one (n=23) or multiple (n=26) of GAD65, IA-2, or ZnT8 AAbs; new onset (NO) T1D patients (n=63, duration 1.0 ± 0.7 months); and established T1D patients (n=68, duration 4.4 ± 3.7 years). IGF1 and IGF2 levels were significantly lower in AAb+ FDR compared to AAb- FDR (204 ± 117 vs. 346 ± 160 ng/mL, p<0.001; 701 ± 496 vs. 1054 ± 721 ng/mL, p<0.01). Lower IGF1 levels were noted in single AAb+ FDR (183 ± 112 ng/mL, p<0.0001), while lower IGF2 levels remained significant in multiple AAb+ FDR only (686 ± 535 ng/mL, p<0.05). IGFBP1 levels were increased in AAb+ FDR compared to AAb- FDR (3.6 ± 3.2 vs. 1.8 ± 1.7 ng/mL, p<0.01), and this was apparent in single AAb+ FDR (4.5 ± 4.0 ng/mL, p<0.001). IGFBP7 levels were significantly lower in multiple AAb+ FDR as compared to AAb- FDR (79 ± 21 vs. 95 ± 22 ng/mL, p<0.05). Additionally, we established a multiple logistic regression model evaluating age, IGFs, and IGFBPs (IGFBP1, -3, and -7), which could effectively discriminate AAb+ FDR from CTRL (AUC = 0.84). These data suggest a dysregulated IGF axis is present prior to symptomatic T1D and may provide new biomarkers to improve disease prediction. Disclosure M. Shapiro: None. C. Wasserfall: None. A.R. Schultz: None. S.M. McGrail: None. M.J. Haller: None. D. Schatz: None. M.A. Atkinson: Other Relationship; Self; Patent Issued. T.M. Brusko: Stock/Shareholder; Self; OneVax, LLC. Advisory Panel; Self; Caladrius Biosciences, Inc.. Consultant; Self; Merck & Co., Inc., Sanofi-Aventis.

e14585 Background: Immune checkpoint inhibitors are approved to treat a variety of solid tumors and Hodgkin’s Lymphoma. However, they have not been shown to be effective against Non-Hodgkin’s Lymphoma (NHL). Unfortunately, their use is associated with induction of autoimmune reactions, termed immune mediated side-effects (irAEs) (1-3). AVM0703 is an immunomodulatory drug which mobilizes bispecific gd and invariant TCR double-positive NKT-like cells (AVM_NKT), currently enrolling a Phase 2 clinical trial to treat R/R NHL of all subtypes based on strong activity against the aggressive, immune-resistant mouse A20 lymphoma. Unlike the checkpoint inhibitors which trigger irAEs, gdTCR expression of the AVM0703 mobilized AVM_NKT, suggests that AVM0703 should not trigger irAEs, and in fact might be a treatment for autoimmune diseases such as type 1 diabetes (T1D). As monotherapy in the A20 lymphoma model, AVM0703 completely eradicates ~20% of flank tumors, and used as a neoadjuvant prior to cyclophosphamide/fludarabine (CyFlu) it provided additive/synergistic A20 killing. As a single dosed monotherapy, AVM0703 prevented T1D onset in the gold standard NOD model. Reversal of already established T1D has proven difficult, and monotherapy approaches abandoned for lack of efficacy. Based on its activity in combination with CyFlu, and since teplizumab anti-CD3 has been approved to prevent progression to grade 3 T1D in at risk people (4), we investigated the combination with AVM0703 to reverse recent onset T1D in the NOD mouse. Methods: One hundred twenty hyperglycemic non-obese diabetic (NOD) mice were randomized to receive an insulin pellet followed by 1) Oral Placebo (18 mg/kg HED) 2) 5 µg anti-CD3 (for 5 days) i.p. 2) Oral AVM0703 (18 mg/kg HED) – weekly/biweekly/tri-weekly 3) AVM0703 (18 mg/kg HED) followed by 5 µg anti-CD3 (for 5 days) and then AVM0703 – weekly/bi-weekly/tri-weekly. Mice were monitored for body weight, body condition and hyperglycemia. Results: Timing between 18 mg/kg AVM0703 and 5 ug anti-CD3 dosing was taken from lymphoma studies that demonstrated that chemotherapy 3 and 24 hours after AVM0703 dosing maximally eradicated lymphoma. The combinations of AVM0703 (day 1) and anti-CD3 (day 2-6) were able to reverse diabetes in 26 mice for 0-9 weeks, with six mice in ongoing normoglycemia at the time of this report. The combination group that received weekly AVM0703 dosing was more effective than the bi-weekly or tri-weekly AVM0703 groups. Monotherapy with AVM0703 did not reverse diabetes, in contrast to its profound ability to prevent or delay diabetes onset in the NOD model. Conclusions: We hypothesize that the combination of AVM0703 and anti-CD3 will be more effective when anti-CD3 is added 5 days after AVM0703. 1) Tocut, Autoimmun Rev 2018. 2) Sakowska, Front Immunol 2022. 3) Sherry, Lancet. 2011. 4) Hagopian, Diabetes 2013.