Browsing by Subject "CD26"

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    High-dose sitagliptin for systemic inhibition of dipeptidylpeptidase-4 to enhance engraftment of single cord umbilical cord blood transplantation
    (Impact Journals, 2017-11-27) Farag, Sherif S.; Nelson, Robert; Cairo, Mitchell S.; O’Leary, Heather A.; Zhang, Shuhong; Huntley, Carol; Delgado, David; Schwartz, Jennifer; Zaid, Mohammad Abu; Abonour, Rafat; Robertson, Michael; Broxmeyer, Hal; Medicine, School of Medicine
    Delayed engraftment remains a limitation of umbilical cord blood (UCB) transplantation. We previously showed that inhibition of dipeptidylpeptidase (DPP)-4 using sitagliptin 600 mg daily was safe with encouraging results on engraftment, but inhibition was not sustained. We evaluated the efficacy and feasibility of higher doses of sitagliptin to enhance engraftment of UCB in patients with hematological cancers. Fifteen patients, median age 41 (range, 18-59) years, received single UCB grafts matched at 4 (n=11) or 5 (n=4) of 6 HLA loci with median nucleated cell dose of 3.5 (range, 2.57-4.57) x107/kg. Sitagliptin 600 mg every 12 hours was administered days -1 to +2. All patients engrafted by day 30, with 12 (80%) engrafting by day 21. The median time to neutrophil engraftment was 19 (range, 12-30) days. Plasma DPP-4 activity was better inhibited with a mean residual trough DPP-4 activity of 70%±19%. Compared to patients previously treated with 600 mg/day, sitagliptin 600 mg every 12 hours appeared to improve engraftment, supporting the hypothesis that more sustained DPP-4 inhibition is required. In-vivo inhibition of DPP-4 using high-dose sitagliptin compares favorably with other approaches to enhance UCB engraftment with greater simplicity, and may show synergy in combination with other strategies.
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    Identification of human CD4+ T cell populations with distinct antitumor activity
    (American Association for the Advancement of Science, 2020-07-01) Nelson, Michelle H.; Knochelmann, Hannah M.; Bailey, Stefanie R.; Huff, Logan W.; Bowers, Jacob S.; Majchrzak-Kuligowska, Kinga; Wyatt, Megan M.; Rubinstein, Mark P.; Mehrotra, Shikhar; Nishimura, Michael I.; Armeson, Kent E.; Giresi, Paul G.; Zilliox, Michael J.; Broxmeyer, Hal E.; Paulos, Chrystal M.; Microbiology and Immunology, School of Medicine
    How naturally arising human CD4+ T helper subsets affect cancer immunotherapy is unclear. We reported that human CD4+CD26high T cells elicit potent immunity against solid tumors. As CD26high T cells are often categorized as TH17 cells for their IL-17 production and high CD26 expression, we posited these populations would have similar molecular properties. Here, we reveal that CD26high T cells are epigenetically and transcriptionally distinct from TH17 cells. Of clinical importance, CD26high and TH17 cells engineered with a chimeric antigen receptor (CAR) regressed large human tumors to a greater extent than enriched TH1 or TH2 cells. Only human CD26high T cells mediated curative responses, even when redirected with a suboptimal CAR and without aid by CD8+ CAR T cells. CD26high T cells cosecreted effector cytokines, produced cytotoxic molecules, and persisted long term. Collectively, our work underscores the promise of CD4+ T cell populations to improve durability of solid tumor therapies.