Browsing by Author "Macintyre, Andrew N"

Now showing 1 - 6 of 6
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    Bacteremia in solid organ transplant recipients as compared to immunocompetent patients: Acute phase cytokines and outcomes in a prospective, matched cohort study.
    (American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons, 2021-06) Eichenberger, Emily M; Ruffin, Felicia; Dagher, Michael; Lerebours, Reginald; Jung, Sin-Ho; Sharma-Kuinkel, Batu; Macintyre, Andrew N; Thaden, Joshua T; Sinclair, Matthew; Hale, Lauren; Kohler, Celia; Palmer, Scott M; Alexander, Barbara D; Fowler, Vance G; Maskarinec, Stacey A
    We undertook a prospective, matched cohort study of patients with Staphylococcus aureus bacteremia (SAB) and gram-negative bacteremia (GNB) to compare the characteristics, outcomes, and chemokine and cytokine response in transplant recipients to immunocompetent, nontransplant recipients. Fifty-five transplant recipients (GNB n = 29; SAB n = 26) and 225 nontransplant recipients (GNB n = 114; SAB n = 111) were included for clinical analysis. Transplant GNB had a significantly lower incidence of septic shock than nontransplant GNB (10.3% vs 30.7%, p = .03). Thirty-day mortality did not differ significantly between transplant and nontransplant recipients with GNB (10.3% vs 15.8%, p = .57) or SAB (0.0% vs 11.7%, p = .13). Next, transplant patients were matched 1:1 with nontransplant patients for the chemokine and cytokine analysis. Five cytokines and chemokines were significantly lower in transplant GNB vs nontransplant GNB: IL-2 (median [IQR]: 7.1 pg/ml [7.1, 7.1] vs 32.6 pg/ml [7.1, 88.0]; p = .001), MIP-1β (30.7 pg/ml [30.7, 30.7] vs 243.3 pg/ml [30.7, 344.4]; p = .001), IL-8 (32.0 pg/ml [5.6, 53.1] vs 59.1 pg/ml [39.2, 119.4]; p = .003), IL-15 (12.0 pg/ml [12.0, 12.0] vs 12.0 pg/ml [12.0, 126.7]; p = .03), and IFN-α (5.1 pg/mL [5.1, 5.1] vs 5.1 pg/ml [5.1, 26.3]; p = .04). Regulated upon Activation, Normal T Cell Expressed and Secreted (RANTES) was higher in transplant SAB vs nontransplant SAB (mean [SD]: 750.2 pg/ml [194.6] vs 656.5 pg/ml [147.6]; p = .046).
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    Cutting edge: distinct glycolytic and lipid oxidative metabolic programs are essential for effector and regulatory CD4+ T cell subsets.
    (J Immunol, 2011-03-15) Michalek, Ryan D; Gerriets, Valerie A; Jacobs, Sarah R; Macintyre, Andrew N; MacIver, Nancie J; Mason, Emily F; Sullivan, Sarah A; Nichols, Amanda G; Rathmell, Jeffrey C
    Stimulated CD4(+) T lymphocytes can differentiate into effector T cell (Teff) or inducible regulatory T cell (Treg) subsets with specific immunological roles. We show that Teff and Treg require distinct metabolic programs to support these functions. Th1, Th2, and Th17 cells expressed high surface levels of the glucose transporter Glut1 and were highly glycolytic. Treg, in contrast, expressed low levels of Glut1 and had high lipid oxidation rates. Consistent with glycolysis and lipid oxidation promoting Teff and Treg, respectively, Teff were selectively increased in Glut1 transgenic mice and reliant on glucose metabolism, whereas Treg had activated AMP-activated protein kinase and were dependent on lipid oxidation. Importantly, AMP-activated protein kinase stimulation was sufficient to decrease Glut1 and increase Treg generation in an asthma model. These data demonstrate that CD4(+) T cell subsets require distinct metabolic programs that can be manipulated in vivo to control Treg and Teff development in inflammatory diseases.
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    Engineering a BCR-ABL-activated caspase for the selective elimination of leukemic cells.
    (Proc Natl Acad Sci U S A, 2013-02-05) Kurokawa, Manabu; Ito, Takahiro; Yang, Chih-Sheng; Zhao, Chen; Macintyre, Andrew N; Rizzieri, David A; Rathmell, Jeffrey C; Deininger, Michael W; Reya, Tannishtha; Kornbluth, Sally
    Increased understanding of the precise molecular mechanisms involved in cell survival and cell death signaling pathways offers the promise of harnessing these molecules to eliminate cancer cells without damaging normal cells. Tyrosine kinase oncoproteins promote the genesis of leukemias through both increased cell proliferation and inhibition of apoptotic cell death. Although tyrosine kinase inhibitors, such as the BCR-ABL inhibitor imatinib, have demonstrated remarkable efficacy in the clinic, drug-resistant leukemias emerge in some patients because of either the acquisition of point mutations or amplification of the tyrosine kinase, resulting in a poor long-term prognosis. Here, we exploit the molecular mechanisms of caspase activation and tyrosine kinase/adaptor protein signaling to forge a unique approach for selectively killing leukemic cells through the forcible induction of apoptosis. We have engineered caspase variants that can directly be activated in response to BCR-ABL. Because we harness, rather than inhibit, the activity of leukemogenic kinases to kill transformed cells, this approach selectively eliminates leukemic cells regardless of drug-resistant mutations.
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    Metabolic programming and PDHK1 control CD4+ T cell subsets and inflammation.
    (J Clin Invest, 2015-01) Gerriets, Valerie A; Kishton, Rigel J; Nichols, Amanda G; Macintyre, Andrew N; Inoue, Makoto; Ilkayeva, Olga; Winter, Peter S; Liu, Xiaojing; Priyadharshini, Bhavana; Slawinska, Marta E; Haeberli, Lea; Huck, Catherine; Turka, Laurence A; Wood, Kris C; Hale, Laura P; Smith, Paul A; Schneider, Martin A; MacIver, Nancie J; Locasale, Jason W; Newgard, Christopher B; Shinohara, Mari L; Rathmell, Jeffrey C
    Activation of CD4+ T cells results in rapid proliferation and differentiation into effector and regulatory subsets. CD4+ effector T cell (Teff) (Th1 and Th17) and Treg subsets are metabolically distinct, yet the specific metabolic differences that modify T cell populations are uncertain. Here, we evaluated CD4+ T cell populations in murine models and determined that inflammatory Teffs maintain high expression of glycolytic genes and rely on high glycolytic rates, while Tregs are oxidative and require mitochondrial electron transport to proliferate, differentiate, and survive. Metabolic profiling revealed that pyruvate dehydrogenase (PDH) is a key bifurcation point between T cell glycolytic and oxidative metabolism. PDH function is inhibited by PDH kinases (PDHKs). PDHK1 was expressed in Th17 cells, but not Th1 cells, and at low levels in Tregs, and inhibition or knockdown of PDHK1 selectively suppressed Th17 cells and increased Tregs. This alteration in the CD4+ T cell populations was mediated in part through ROS, as N-acetyl cysteine (NAC) treatment restored Th17 cell generation. Moreover, inhibition of PDHK1 modulated immunity and protected animals against experimental autoimmune encephalomyelitis, decreasing Th17 cells and increasing Tregs. Together, these data show that CD4+ subsets utilize and require distinct metabolic programs that can be targeted to control specific T cell populations in autoimmune and inflammatory diseases.
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    T cell-depleted cultured pediatric thymus tissue as a model for some aspects of human age-related thymus involution.
    (GeroScience, 2021-06) Hale, Laura P; Cheatham, Lynn; Macintyre, Andrew N; LaFleur, Bonnie; Sanders, Brittany; Troy, Jesse; Kurtzberg, Joanne; Sempowski, Gregory D
    Human age-related thymus involution is characterized by loss of developing thymocytes and the thymic epithelial network that supports them, with replacement by adipose tissue. The mechanisms that drive these changes are difficult to study in vivo due to constant trafficking to and from the thymus. We hypothesized that the loss of thymocytes that occurs during human thymic organ cultures could model some aspects of thymus involution and begin to identify mechanisms that drive age-related changes in the thymic microenvironment. Potential mechanistically important candidate molecules were initially identified by screening conditioned media from human thymus organ cultures using antibody microarrays. These candidates were further validated using cultured tissue extracts and conditioned media. Results were compared with gene expression studies from a panel of well-characterized (non-cultured) human thymus tissues from human donors aged 5 days to 78 years. L-selectin released into conditioned media was identified as a biomarker for the content of viable thymocytes within the cultured thymus. Levels of the chemokines CCL21 and CXCL12, likely produced by surviving thymic epithelial cells, increased markedly in conditioned media as thymocytes were lost during culture. Native non-cultured thymus from adults older than 18 years also showed a strong trend toward increased CCL21 expression, in conjunction with significant decreases in thymocyte-related mRNAs compared with thymus from subjects younger than 18 years. Together, these findings demonstrate that use of postnatal human thymus organ cultures can model some aspects of human age-related thymic involution.
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    The functions of SARS-CoV-2 neutralizing and infection-enhancing antibodies in vitro and in mice and nonhuman primates.
    (bioRxiv, 2021-02-18) Li, Dapeng; Edwards, Robert J; Manne, Kartik; Martinez, David R; Schäfer, Alexandra; Alam, S Munir; Wiehe, Kevin; Lu, Xiaozhi; Parks, Robert; Sutherland, Laura L; Oguin, Thomas H; McDanal, Charlene; Perez, Lautaro G; Mansouri, Katayoun; Gobeil, Sophie MC; Janowska, Katarzyna; Stalls, Victoria; Kopp, Megan; Cai, Fangping; Lee, Esther; Foulger, Andrew; Hernandez, Giovanna E; Sanzone, Aja; Tilahun, Kedamawit; Jiang, Chuancang; Tse, Longping V; Bock, Kevin W; Minai, Mahnaz; Nagata, Bianca M; Cronin, Kenneth; Gee-Lai, Victoria; Deyton, Margaret; Barr, Maggie; Holle, Tarra Von; Macintyre, Andrew N; Stover, Erica; Feldman, Jared; Hauser, Blake M; Caradonna, Timothy M; Scobey, Trevor D; Rountree, Wes; Wang, Yunfei; Moody, M Anthony; Cain, Derek W; DeMarco, C Todd; Denny, ThomasN; Woods, Christopher W; Petzold, Elizabeth W; Schmidt, Aaron G; Teng, I-Ting; Zhou, Tongqing; Kwong, Peter D; Mascola, John R; Graham, Barney S; Moore, Ian N; Seder, Robert; Andersen, Hanne; Lewis, Mark G; Montefiori, David C; Sempowski, Gregory D; Baric, Ralph S; Acharya, Priyamvada; Haynes, Barton F; Saunders, Kevin O
    SARS-CoV-2 neutralizing antibodies (NAbs) protect against COVID-19. A concern regarding SARS-CoV-2 antibodies is whether they mediate disease enhancement. Here, we isolated NAbs against the receptor-binding domain (RBD) and the N-terminal domain (NTD) of SARS-CoV-2 spike from individuals with acute or convalescent SARS-CoV-2 or a history of SARS-CoV-1 infection. Cryo-electron microscopy of RBD and NTD antibodies demonstrated function-specific modes of binding. Select RBD NAbs also demonstrated Fc receptor-γ (FcγR)-mediated enhancement of virus infection in vitro , while five non-neutralizing NTD antibodies mediated FcγR-independent in vitro infection enhancement. However, both types of infection-enhancing antibodies protected from SARS-CoV-2 replication in monkeys and mice. Nonetheless, three of 31 monkeys infused with enhancing antibodies had higher lung inflammation scores compared to controls. One monkey had alveolar edema and elevated bronchoalveolar lavage inflammatory cytokines. Thus, while in vitro antibody-enhanced infection does not necessarily herald enhanced infection in vivo , increased lung inflammation can occur in SARS-CoV-2 antibody-infused macaques.