University of California San Francisco

Amar Nijagal
Amar
Nijagal
MD

Associate Professor of Surgery
Division of Pediatric Surgery
UCSF Benioff Children's Hospital, San Francisco
Surgical Director, UCSF Pediatric Liver Center

UCSF Diversity, Equity, and Inclusion Champion badge

Address

513 Parnassus Avenue, HSW, #1619
San Francisco, CA 94143
United States

Email: amar.nijagal@ucsf.edu
Phone: 415-476-4086
Fax: 415-476-5363

ORCID: 0000-0003-2200-6887

Biography

Dr. Amar Nijagal is a pediatric surgeon who specializes in caring for children with disorders of the liver and bile ducts.

The Nijagal lab investigates how the immune system affects the development of fetal organs. His research focuses on liver and bile duct development and how changes in the process contribute to congenital diseases and childhood liver cancer.

Dr. Nijagal completed his medical degree and a residency in general surgery at UCSF, where he served as chief resident. He completed a postdoctoral research fellowship at the California Institute for Regenerative Medicine and a fellowship in general and thoracic pediatric surgery at Boston Children's Hospital. He is a member of the American College of Surgeons, American Pediatric Surgical Association, American Association for the Study of Liver Diseases, UCSF Naffziger Surgical Society, and Association for Academic Surgery.

Awards & Honors

Award Conferred By Date
Haile T. Debas Academy of Medical Educators Excellence in Mentoring Award for UCSF Teaching Faculty UCSF Haile T. Debas Academy of Medical Educators 2024/2024
UCSF Society of Hellman Fellow Hellman Fellows Program 2023/2025
Cancer Research Coordinating Committee Faculty Seed Grant University of CA Office of the President 2022/2022
Clinical, Translational, and Outcomes Research Award American Association for the Study of Liver Diseases 2021/2023
Franklin H. Martin, MD, FACS Faculty Research Fellowship American College of Surgeons 2019/2021
APSA Foundation Jay Grosfeld, MD Scholar Research Award American Pediatric Surgical Association 2018/2019
Esther Nusz Achievement Award UCSF Department of Surgery 2014
Medical Student Teaching Award UCSF Department of Surgery 2014
Medical Student Teaching Award UCSF Department of Surgery 2013
M. Judah Folkman Memorial Award-Best Podium Presentation American Pediatric Surgical Association 2012
M. Judah Folkman Memorial Award-Best Podium Presentation American Pediatric Surgical Association 2011
Camille Vandenberge-Storz Young Investigators' Award International Fetal and Maternal Surgical Society 2011
Clinical Fellow Research Training Award California Institute for Regenerative Medicine 2009/2012
Resident Research Award Association of Academic Surgeons 2009
Alpha Omega Alpha UCSF School of Medicine 2005

Education

Institution Degree Dept or School End Date
University of California Diversity, Equity, and Inclusion Champion Training 05/2021
Boston Children's Hospital Fellowship Pediatric General and Thoracic Surgery 2016
University of California, San Francisco Residency Department of Surgery 2014
University of California , San Francisco Postdoctoral Fellowship Maternal-Fetal Immunology 06/2012
University of California, San Francisco M.D. Medicine 2006
University of California, Los Angeles HHMI Research Fellowship Immunology 06/2004

Board Certifications

American Board of Surgery, General Surgery

Clinical Expertise

Hepatobiliary surgery
Neonatal surgery
Minimally invasive surgery
Pediatric Surgery

Program Affiliations

Biomedical Sciences Program

Fetal Treatment Center

UCSF Liver Center

Abstracts

A Nijagal, M Wegorzewska, T Le, TC MacKenzie. Fetal intervention triggers the activation of paternal antigen-specific maternal T cells. American Pediatric Surgical Association 43rd Annual Meeting, San Antonio, TX, May 2011. accepted.

A Nijagal, S Fleck, NK Hills, S Feng, Q Tang, SM Kang, P Rosenthal, TC MacKenzie. Maternal liver transplantation in patients with biliary atresia leads to lower risk of graft failure. American Academy of Pediatrics Annual Conference, Boston, MA. 2011.

A Nijagal, T Le, M Wegorzewska, A Tucker, TC MacKenzie. Peripheral tolerance mechanisms are important for the maintenance of donor cell engraftment after in utero hematopoietic cell transplantation. American College of Surgeons 97th Annual Clinical Congress, San Francisco, CA. 2011.

A Nijagal, M Wegorzewska, T Le, J Gonzalez, TC MacKenzie. The maternal adaptive immune response against paternal antigens incites fetal demise after detal intervention. American Pediatric Surgical Association 42nd Annual Meeting, Palm Springs, CA, May 2011.

G Bautista, KD Gonzales, A Nijagal, C Ward, DN Miniati, H Lee, S Keating, P Norris, TH Lee, M Busch, TC MacKenzie. Maternal-fetal cellular signaling mechanisms in severe congenital giaphragmatic hernia. American Pediatric Surgical Association 42nd Annual Meeting, Palm Springs, CA, May 2011.

A Nijagal, T Le, M Wegorzewska, A Tucker, Q Tang, TC MacKenzie. Regulatory T cells establish and maintain chimerism after in utero hematopoietic cell transplantation, IMMUNOLOGY 2011. 98th Annual Meeting of the American Association of Immunologists, San Francisco, CA 2011.

A Nijagal, M Wegorzewska, T Le, A Tucker, Q Tang, TC MacKenzie. Altered T cell profiles in uterine draining lymph nodes of mice with preterm labor, IMMUNOLOGY 2011. 98th Annual Meeting of the American Association of Immunologists, San Francisco, CA 2011.

M Wegorzewska, A Nijagal, T Le, A Tucker, Q Tang, TC MacKenzie. Preterm labor leads to activation and proliferation of maternal T cells which recognize the paternal alloantigen via the indirect pathway, IMMUNOLOGY 2011. 98th Annual Meeting of the American Association of Immunologists, San Francisco, CA 2011.

A Nijagal, S Fleck, SM Kang, P Rosenthal, TC MacKenzie. Improved outcomes of living related liver transplantation with maternal donors in patients with biliary atresia, American Academy of Pediatrics Annual Conference, San Francisco, CA 2010.

TC MacKenzie, A Nijagal, T Le, M Wegorzewska, Q Tang. Indirect antigen presentation following in utero HSC transplantation leads to clonal deletion of antigen specific T effector cells with formation of Tregs. International Society for Stem Cell Research 8th Annual Meeting, San Francisco, CA. June 2010.

L Landsman, A Nijagal, WE Zimmer, T MacKenzie, M Hebrok. Transgenic studies reveal essential roles for embryonic pancreatic mesenchyme. Cold Spring Harbor Vertebrate Organogenesis, Cold Spring Harbor, NY. April 2010.

A Nijagal, M Wegorzewska, E Jarvis, T Le, Q Tang, and T MacKenzie. The maternal immune response limits engraftment after in utero hematopoietic stem cell transplantation. California Institute for Regenerative Medicine 2010 Grantee Meeting. San Francisco, CA. March 2010.

T MacKenzie, E Jarvis, A Nijagal, T Le, M Wegorzewska, and Q Tang. The maternal immune response to in utero hematopoietic stem cell transplantation. The American Society of Hematology, New Orleans, LA. . December 2009.

 

Grants and Funding

  • Novel immune mechanisms regulating the balance between homeostasis and malignancy in the developing liver | UCSF Society of Hellman Fellows | 2023-07-01 - 2025-06-30 | Role: PI
  • Deciphering the role of macrophage mediated signals on immune tolerance in the developing liver | NIH/NIDDK | 2024-06-01 - 2025-05-30 | Role: PI
  • Defining the role of tumor associated myeloid cells in pediatric hepatoblastoma | American Association for the Study of Liver Diseases | 2021-07-01 - 2023-06-30 | Role: PI
  • The cooperative relationship between neutrophils and monocytes during neonatal liver inflammation: insight into the pathogenesis of biliary atresia | Franklin H. Martin, MD, FACS Faculty Research Fellowship, American College of Surgeons | 2019-07-01 - 2021-06-30 | Role: PI
  • Single cell characterization and organoid development of pediatric choledochal cysts and hepatoblastoma to understand the link between liver development and hepatobiliary malignancy | American Cancer Society | 2020-02-01 - 2021-01-31 | Role: PI
  • The Role of Monocytes During the Resolution of Perinatal Liver Inflammation | UCSF Liver Center | 2019-06-01 - 2020-05-31 | Role: PI
  • Investigating the Fetal Mechanisms of Liver and Bile Duct Repair: A Link to the Prenatal Origins of Biliary Atresia | American Pediatric Surgical Association | 2018-07-01 - 2019-06-30 | Role: PI

Research Narrative

Investigating How Immune Cells Regulate the Development and Repair of Fetal Organs

We study how immune cells may regulate the development and repair of fetal organs.  Our research is currently focused on the development of the liver and bile ducts as the fetal liver is ripe with interactions between developing hepatocytes/cholangiocytes and the hematopoietic system.  We are interested in identifying key relationships and interactions between immune cells and developing tissues in both the steady state and during fetal injury.  Using advanced surgical techniques in mouse models, we are able to manipulate and induce injury in fetal organs.  We have also employed “discovery” approaches to identify novel cell types and pathways that may serve as a link between the immune system and fetal development. 

Research Interests

Immunology at the maternal-fetal interface

Research Pathways

Basic Biomedical & Translational Research

Publications

MOST RECENT PUBLICATIONS FROM A TOTAL OF 42
  1. Immunology of Biliary Atresia.
    Miller PN, Baskaran S, Nijagal A| | PubMed
  2. Perinatal liver inflammation is associated with persistent elevation of CXCL10 and its canonical receptor CXCR3 on common myeloid progenitors.
    Alkhani A, Baskaran S, Murti A, Rapp B, Levy CS, Wang B, Nijagal A| | PubMed
  3. Index admission cholecystectomy for acute cholecystitis reduces 30-day readmission rates in pediatric patients.
    Pathak SJ, Ji H, Nijagal A, Avila P, Dai SC, Arain MA, Kouanda A| | PubMed
  4. Neonatal Hepatic Myeloid Progenitors Expand and Propagate Liver Injury in Mice.
    Alkhani A, Korsholm C, Levy CS, Mohamedaly S, Duwaerts CC, Pietras EM, Nijagal A| | PubMed
  5. Advances in the Treatment of Neonatal Biliary Disease.
    Mohamedaly S, Nijagal A| | PubMed
  6. Hepatic Ly6CLo Non-Classical Monocytes Have Increased Nr4a1 (Nur77) in Murine Biliary Atresia.
    Mohamedaly S, Levy CS, Korsholm C, Alkhani A, Rosenberg K, Ashouri JF, Nijagal A| | PubMed
  7. Single-cell analysis of hepatoblastoma identifies tumor signatures that predict chemotherapy susceptibility using patient-specific tumor spheroids.
    Song H, Bucher S, Rosenberg K, Tsui M, Burhan D, Hoffman D, Cho SJ, Rangaswami A, Breese M, Leung S, Ventura MVP, Sweet-Cordero EA, Huang FW, Nijagal A, Wang B| | PubMed
  8. The need for early Kasai portoenterostomy: a Western Pediatric Surgery Research Consortium study.
    Kelley-Quon LI, Shue E, Burke RV, Smith C, Kling K, Mahdi E, Ourshalimian S, Fenlon M, Dellinger M, Shew SB, Lee J, Padilla B, Inge T, Roach J, Marwan AI, Russell KW, Ignacio R, Fialkowski E, Nijagal A, Im C, Azarow KS, Ostlie DJ, Wang K| | PubMed
  9. Neutrophils are important for the development of pro-reparative macrophages after irreversible electroporation of the liver in mice.
    Lopez-Ichikawa M, Vu NK, Nijagal A, Rubinsky B, Chang TT| | PubMed
  10. The Role of Myeloid Populations during Perinatal Liver Injury and Repair.
    Alkhani A, Mohamedaly S, Nijagal A| | PubMed
  11. The natural history of fetal gallstones: a case series and updated literature review.
    Schwab ME, Braun HJ, Feldstein VA, Nijagal A| | PubMed
  12. The relative abundance of monocyte subsets determines susceptibility to perinatal hepatic inflammation.
    Mohamedaly S, Alkhani A, Nijagal A| | PubMed
  13. Ly6cLo non-classical monocytes promote resolution of rhesus rotavirus-mediated perinatal hepatic inflammation.
    Alkhani A, Levy CS, Tsui M, Rosenberg KA, Polovina K, Mattis AN, Mack M, Van Dyken S, Wang BM, Maher JJ, Nijagal A| | PubMed
  14. Natural history of acute pediatric iliofemoral artery thrombosis treated with anticoagulation.
    Ramirez JL, Kuhrau CR, Wu B, Zarkowsky DS, Conte MS, Oskowitz AZ, Nijagal A, Vartanian SM| | PubMed
  15. De novo somatic mutations and KRAS amplification are associated with cholangiocarcinoma in a patient with a history of choledochal cyst.
    Schwab ME, Song H, Mattis A, Phelps A, Vu LT, Huang FW, Nijagal A| | PubMed
  16. Congenital superior mesenteric artery aneurysm in a 6-week-old infant presenting with upper gastrointestinal bleeding.
    Subbaraj L, Beleniski F, Courtier J, Vartanian S, Nijagal A| | PubMed
  17. Treating Biliary Atresia: The Challenge Continues.
    Nijagal A, Perito ER| | PubMed
  18. Editorial: Treating Biliary Atresia: The Challenge Continues.
    Nijagal A, Perito ER| | PubMed
  19. Late-onset hypertrophic pyloric stenosis with gastric outlet obstruction: case report and review of the literature.
    Wolf LL, Nijagal A, Flores A, Buchmiller TL| | PubMed
  20. Fetal intervention increases maternal T cell awareness of the foreign conceptus and can lead to immune-mediated fetal demise.
    Wegorzewska M, Nijagal A, Wong CM, Le T, Lescano N, Tang Q, MacKenzie TC| | PubMed
  21. Direct and indirect antigen presentation lead to deletion of donor-specific T cells after in utero hematopoietic cell transplantation in mice.
    Nijagal A, Derderian C, Le T, Jarvis E, Nguyen L, Tang Q, Mackenzie TC| | PubMed
  22. Clinical implications of maternal-fetal cellular trafficking.
    Nijagal A, MacKenzie TC| | PubMed
  23. The diagnosis and management of intradiaphragmatic extralobar pulmonary sequestrations: a report of 4 cases.
    Nijagal A, Jelin E, Feldstein VA, Courtier J, Urisman A, Jones KD, Lee H, Hirose S, MacKenzie TC| | PubMed
  24. Alterations in maternal-fetal cellular trafficking after fetal surgery.
    Saadai P, Lee TH, Bautista G, Gonzales KD, Nijagal A, Busch MP, Kim CJ, Romero R, Lee H, Hirose S, Rand L, Miniati D, Farmer DL, MacKenzie TC| | PubMed
  25. Long-term outcomes after fetal therapy for congenital high airway obstructive syndrome.
    Saadai P, Jelin EB, Nijagal A, Schecter SC, Hirose S, MacKenzie TC, Rand L, Goldstein R, Farrell J, Harrison M, Lee H| | PubMed
  26. In utero hematopoietic cell transplantation for the treatment of congenital anomalies.
    Nijagal A, Flake AW, MacKenzie TC| | PubMed
  27. Maternal microchimerism in patients with biliary atresia: Implications for allograft tolerance.
    Nijagal A, Fleck S, MacKenzie TC| | PubMed
  28. Decreased risk of graft failure with maternal liver transplantation in patients with biliary atresia.
    Nijagal A, Fleck S, Hills NK, Feng S, Tang Q, Kang SM, Rosenthal P, MacKenzie TC| | PubMed
  29. Pancreatic mesenchyme regulates epithelial organogenesis throughout development.
    Landsman L, Nijagal A, Whitchurch TJ, Vanderlaan RL, Zimmer WE, Mackenzie TC, Hebrok M| | PubMed
  30. Dynamic tracheal occlusion improves lung morphometrics and function in the fetal lamb model of congenital diaphragmatic hernia.
    Jelin EB, Etemadi M, Encinas J, Schecter SC, Chapin C, Wu J, Guevara-Gallardo S, Nijagal A, Gonzales KD, Ferrier WT, Roy S, Miniati D| | PubMed
  31. The maternal immune response inhibits the success of in utero hematopoietic cell transplantation.
    Nijagal A, Wegorzewska M, Le T, Tang Q, Mackenzie TC| | PubMed
  32. A mouse model of in utero transplantation.
    Nijagal A, Le T, Wegorzewska M, Mackenzie TC| | PubMed
  33. Maternal T cells limit engraftment after in utero hematopoietic cell transplantation in mice.
    Nijagal A, Wegorzewska M, Jarvis E, Le T, Tang Q, MacKenzie TC| | PubMed
  34. Intrauterine umbilical cord hemorrhage with associated jejunal atresia captured by real-time ultrasound.
    Nijagal A, Rand L, Goldstein R, Poder L, Miniati D| | PubMed
  35. Colonic atresia and choledochal cyst: a rare combination.
    Nijagal A, Ozgediz D, Feldstein VA, Lee H, Harrison MR| | PubMed
  36. Molecular markers for gastric adenocarcinoma: an update.
    Anderson C, Nijagal A, Kim J| | PubMed
  37. Normal immune development and glucocorticoid-induced thymocyte apoptosis in mice deficient for the T-cell death-associated gene 8 receptor.
    Radu CG, Cheng D, Nijagal A, Riedinger M, McLaughlin J, Yang LV, Johnson J, Witte ON| | PubMed
  38. Visualization of a primary anti-tumor immune response by positron emission tomography.
    Shu CJ, Guo S, Kim YJ, Shelly SM, Nijagal A, Ray P, Gambhir SS, Radu CG, Witte ON| | PubMed
  39. Differential proton sensitivity of related G protein-coupled receptors T cell death-associated gene 8 and G2A expressed in immune cells.
    Radu CG, Nijagal A, McLaughlin J, Wang L, Witte ON| | PubMed
  40. Spontaneous resolution of prenatal megalourethra.
    Nijagal A, Sydorak RM, Feldstein VA, Hirose S, Albanese CT| | PubMed
  41. Gastroschisis: small hole, big cost.
    Sydorak RM, Nijagal A, Sbragia L, Hirose S, Tsao K, Phibbs RH, Schmitt SK, Lee H, Farmer DL, Harrison MR, Albanese CT| | PubMed
  42. Endoscopic techniques in fetal surgery.
    Sydorak RM, Nijagal A, Albanese CT| | PubMed