2
|
Hoy MJ, Park E, Lee H, Lim WY, Cole DC, DeBouver ND, Bobay BG, Pierce PG, Fox D, Ciofani M, Juvvadi PR, Steinbach W, Hong J, Heitman J. Structure-Guided Synthesis of FK506 and FK520 Analogs with Increased Selectivity Exhibit In Vivo Therapeutic Efficacy against Cryptococcus. mBio 2022; 13:e0104922. [PMID: 35604094 PMCID: PMC9239059 DOI: 10.1128/mbio.01049-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 04/21/2022] [Indexed: 01/04/2023] Open
Abstract
Calcineurin is an essential virulence factor that is conserved across human fungal pathogens, including Cryptococcus neoformans, Aspergillus fumigatus, and Candida albicans. Although an excellent target for antifungal drug development, the serine-threonine phosphatase activity of calcineurin is conserved in mammals, and inhibition of this activity results in immunosuppression. FK506 (tacrolimus) is a naturally produced macrocyclic compound that inhibits calcineurin by binding to the immunophilin FKBP12. Previously, our fungal calcineurin-FK506-FKBP12 structure-based approaches identified a nonconserved region of FKBP12 that can be exploited for fungus-specific targeting. These studies led to the design of an FK506 analog, APX879, modified at the C-22 position, which was less immunosuppressive yet maintained antifungal activity. We now report high-resolution protein crystal structures of fungal FKBP12 and a human truncated calcineurin-FKBP12 bound to a natural FK506 analog, FK520 (ascomycin). Based on information from these structures and the success of APX879, we synthesized and screened a novel panel of C-22-modified compounds derived from both FK506 and FK520. One compound, JH-FK-05, demonstrates broad-spectrum antifungal activity in vitro and is nonimmunosuppressive in vivo. In murine models of pulmonary and disseminated C. neoformans infection, JH-FK-05 treatment significantly reduced fungal burden and extended animal survival alone and in combination with fluconazole. Furthermore, molecular dynamic simulations performed with JH-FK-05 binding to fungal and human FKBP12 identified additional residues outside the C-22 and C-21 positions that could be modified to generate novel FK506 analogs with improved antifungal activity. IMPORTANCE Due to rising rates of antifungal drug resistance and a limited armamentarium of antifungal treatments, there is a paramount need for novel antifungal drugs to treat systemic fungal infections. Calcineurin has been established as an essential and conserved virulence factor in several fungi, making it an attractive antifungal target. However, due to the immunosuppressive action of calcineurin inhibitors, they have not been successfully utilized clinically for antifungal treatment in humans. Recent availability of crystal structures of fungal calcineurin-bound inhibitor complexes has enabled the structure-guided design of FK506 analogs and led to a breakthrough in the development of a compound with increased fungal specificity. The development of a calcineurin inhibitor with reduced immunosuppressive activity and maintained therapeutic antifungal activity would add a significant tool to the treatment options for these invasive fungal infections with exceedingly high rates of mortality.
Collapse
Affiliation(s)
- Michael J. Hoy
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Eunchong Park
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Hyunji Lee
- Department of Chemistry, Duke University, Durham, North Carolina, USA
| | - Won Young Lim
- Department of Chemistry, Duke University, Durham, North Carolina, USA
| | - D. Christopher Cole
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Nicholas D. DeBouver
- UCB Biosciences, Bainbridge Island, Washington, USA
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington, USA
| | | | - Phillip G. Pierce
- UCB Biosciences, Bainbridge Island, Washington, USA
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington, USA
| | - David Fox
- UCB Biosciences, Bainbridge Island, Washington, USA
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington, USA
| | - Maria Ciofani
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Praveen R. Juvvadi
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - William Steinbach
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Jiyong Hong
- Department of Chemistry, Duke University, Durham, North Carolina, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| |
Collapse
|
3
|
Juvvadi PR, Fox D, Bobay BG, Hoy MJ, Gobeil SMC, Venters RA, Chang Z, Lin JJ, Averette AF, Cole DC, Barrington BC, Wheaton JD, Ciofani M, Trzoss M, Li X, Lee SC, Chen YL, Mutz M, Spicer LD, Schumacher MA, Heitman J, Steinbach WJ. Harnessing calcineurin-FK506-FKBP12 crystal structures from invasive fungal pathogens to develop antifungal agents. Nat Commun 2019; 10:4275. [PMID: 31537789 PMCID: PMC6753081 DOI: 10.1038/s41467-019-12199-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 08/23/2019] [Indexed: 12/16/2022] Open
Abstract
Calcineurin is important for fungal virulence and a potential antifungal target, but compounds targeting calcineurin, such as FK506, are immunosuppressive. Here we report the crystal structures of calcineurin catalytic (CnA) and regulatory (CnB) subunits complexed with FK506 and the FK506-binding protein (FKBP12) from human fungal pathogens (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans and Coccidioides immitis). Fungal calcineurin complexes are similar to the mammalian complex, but comparison of fungal and human FKBP12 (hFKBP12) reveals conformational differences in the 40s and 80s loops. NMR analysis, molecular dynamic simulations, and mutations of the A. fumigatus CnA/CnB-FK506-FKBP12-complex identify a Phe88 residue, not conserved in hFKBP12, as critical for binding and inhibition of fungal calcineurin. These differences enable us to develop a less immunosuppressive FK506 analog, APX879, with an acetohydrazine substitution of the C22-carbonyl of FK506. APX879 exhibits reduced immunosuppressive activity and retains broad-spectrum antifungal activity and efficacy in a murine model of invasive fungal infection.
Collapse
Affiliation(s)
- Praveen R Juvvadi
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, NC, 27710, USA.
| | - David Fox
- Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA, 98110, USA
- UCB Pharma., 7869 NE Day Road West, Bainbridge Island, WA, 98110, USA
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA, USA
| | - Benjamin G Bobay
- Duke University NMR Center, Duke University Medical Center, Durham, NC, 27710, USA
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
- Department of Radiology, Duke University, Durham, NC, 27710, USA
| | - Michael J Hoy
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Sophie M C Gobeil
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
- Department of Radiology, Duke University, Durham, NC, 27710, USA
| | - Ronald A Venters
- Duke University NMR Center, Duke University Medical Center, Durham, NC, 27710, USA
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
- Department of Radiology, Duke University, Durham, NC, 27710, USA
| | - Zanetta Chang
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Jackie J Lin
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Anna Floyd Averette
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - D Christopher Cole
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, NC, 27710, USA
| | - Blake C Barrington
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, NC, 27710, USA
| | - Joshua D Wheaton
- Department of Immunology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Maria Ciofani
- Department of Immunology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Michael Trzoss
- Amplyx Pharmaceuticals, 3210 Merryfield Row, San Diego, CA, 92121, USA
| | - Xiaoming Li
- Amplyx Pharmaceuticals, 3210 Merryfield Row, San Diego, CA, 92121, USA
- Forge Therapeutics, Inc., 10578 Science Center Drive, San Diego, CA, 92121, USA
| | - Soo Chan Lee
- South Texas Center for Emerging Infectious Diseases, Department of Biology, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Ying-Lien Chen
- Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, 10617, Taiwan
| | - Mitchell Mutz
- Amplyx Pharmaceuticals, 3210 Merryfield Row, San Diego, CA, 92121, USA
- Genentech Inc., 1 DNA Way, San Francisco, CA, 94080, USA
| | - Leonard D Spicer
- Duke University NMR Center, Duke University Medical Center, Durham, NC, 27710, USA
- Department of Biochemistry, Duke University, Durham, NC, 27710, USA
- Department of Radiology, Duke University, Durham, NC, 27710, USA
| | | | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - William J Steinbach
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, NC, 27710, USA.
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, 27710, USA.
| |
Collapse
|
8
|
Stuetz A, Baumann K, Grassberger M, Wolff K, Meingassner JG. Discovery of Topical Calcineurin Inhibitors and Pharmacological Profile of Pimecrolimus. Int Arch Allergy Immunol 2006; 141:199-212. [PMID: 16926539 DOI: 10.1159/000095289] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Using a newly developed model of allergic contact dermatitis in pigs, calcineurin inhibitors of the tacrolimus and ascomycin type were shown to have a highly anti-inflammatory action after topical application. These findings provided the first pharmacological evidence of the efficacy of this novel class of topical agents in the treatment of inflammatory skin diseases, and, thus, their potential to become the first alternative to corticosteroids in more than 40 years. As a result of a large research program into ascomycins, pimecrolimus (Elidel(R), SDZ ASM 981) was selected for development due to its favorable pharmacology and safety profile, alongside tacrolimus (Protopic(R), FK 506). In vitro, pimecrolimus inhibits the transcription and release of pro-inflammatory cytokines in T cells. Similar to the corticosteroids, betamethasone-17-valerate and dexamethasone, pimecrolimus is effective at nanomolar concentrations. Targeting mainly T cells, pimecrolimus has, however, a more specific mode of action. Moreover, in contrast to corticosteroids, pimecrolimus has no effect on Langerhans' cells, the professional antigen- presenting dendritic cells of the skin that are crucial for local immunosurveillance. When applied topically, pimecrolimus exerts a high and selective anti-inflammatory activity in the skin, shows minimal percutaneous absorption, and has a low potential to affect systemic immunoreactions. Pimecrolimus cream 1% has proven to be well tolerated, safe, and highly effective in clinical studies in patients with atopic dermatitis.
Collapse
Affiliation(s)
- Anton Stuetz
- Novartis Institutes for BioMedical Research Vienna, Vienna, Austria.
| | | | | | | | | |
Collapse
|