Humberto Trejo Bittar, MD

Dr. Trejo Bittar received an MD from Universidad Central de Venezuela Luis Razetti School of Medicine in Caracas. He completed an Anatomic Pathology Residency and a Thoracic Pathology Fellowship at the University of Pittsburgh School of Medicine. Prior to joining us, Dr. Trejo Bittar was Assistant Professor of Pathology at the University of Pittsburgh Medical Center, Department of Pathology, Division of Anatomic Pathology.  Dr. Trejo Bittar’s clinical interest is benign and malignant lung neoplasms. His research focuses on developing tools to identify genomic alterations of lung carcinomas and improving pathologic and clinical staging of lung neoplasms.

• Waqas A, Khan A, Ozturk ZG, Saeed-Vafa D, Chen W, Dhillon J, Bychkov A, Bui MM, Ullah E, Khalil F, Chumbalkar V, Jameel Z, Bittar HT, Singh RS, Parwani AV, Schabath MB, Rasool G. REASONING BEYOND ACCURACY: EXPERT EVALUATION OF LARGE LANGUAGE MODELS IN DIAGNOSTIC PATHOLOGY. medRxiv. 2025 Apr. Pubmedid: 40297448. Pmcid: PMC12036407.
• Snyder ME, Bondonese A, Craig A, Popescu I, Morrell MR, Myerburg MM, Iasella CJ, Lendermon E, Pilweski J, Johnson B, Kilaru S, Zhang Y, Trejo Bittar HE, Wang X, Sanchez PG, Lakkis F, McDyer J. Rate of recipient-derived alveolar macrophage development and major histocompatibility complex cross-decoration after lung transplantation in humans. Am J Transplant. 2022 Feb.22(2):574-587. Pubmedid: 34431221. Pmcid: PMC9161707.
• Camiolo MJ, Zhou X, Wei Q, Trejo Bittar HE, Kaminski N, Ray A, Wenzel SE. Machine learning implicates the IL-18 signaling axis in severe asthma. JCI Insight. 2021 Nov.6(21). Pubmedid: 34591794. Pmcid: PMC8663569.
• Valenzi E, Tabib T, Papazoglou A, Sembrat J, Trejo Bittar HE, Rojas M, Lafyatis R. Disparate Interferon Signaling and Shared Aberrant Basaloid Cells in Single-Cell Profiling of Idiopathic Pulmonary Fibrosis and Systemic Sclerosis-Associated Interstitial Lung Disease. Front Immunol. 2021 Mar.12:595811. Pubmedid: 33859634. Pmcid: PMC8042271.
• Lajara S, Trejo Bittar HE, Monaco SE, Pantanowitz L. Pulmonary carcinomas arising in association with scar: Cytomorphologic features in histologically confirmed cases. Diagn Cytopathol. 2021 Jun.49(6):753-760. Pubmedid: 33764698.
• Cárdenes N, Sembrat J, Noda K, Lovelace T, Álvarez D, Bittar HET, Philips BJ, Nouraie M, Benos PV, Sánchez PG, Rojas M. Human ex vivo lung perfusion: a novel model to study human lung diseases. Sci Rep. 2021 Jan.11(1):490. Pubmedid: 33436736. Pmcid: PMC7804395.
• Rosenzweig M, Miller LA, Lee AV, Oesterreich S, Trejo Bittar HE, Atkinson JM, Welsh A. The Development and Implementation of an Autopsy/ Tissue Donation for Breast Cancer Research. New Bioeth. 2021 Dec.27(4):349-361. Pubmedid: 34797208.
• Jerome JA, Wenzel SE, Trejo Bittar HE. Digital Imaging Analysis Reveals Reduced Alveolar α-Smooth Muscle Actin Expression in Severe Asthma. Appl Immunohistochem Mol Morphol. 2021 Aug.29(7):506-512. Pubmedid: 33710120. Pmcid: PMC8373652.
• Li X, Noell G, Tabib T, Gregory AD, Trejo Bittar HE, Vats R, Kaminski TW, Sembrat J, Snyder ME, Chandra D, Chen K, Zou C, Zhang Y, Sundd P, McDyer JF, Sciurba F, Rojas M, Lafyatis R, Shapiro SD, Faner R, Nyunoya T. Single cell RNA sequencing identifies IGFBP5 and QKI as ciliated epithelial cell genes associated with severe COPD. Respir Res. 2021 Apr.22(1):100. Pubmedid: 33823868. Pmcid: PMC8022543.
• Tao M, Palmer B, Tavakoli S, Trejo Bittar HE. Erdheim-Chester Disease: A Case of Right Atrial Involvement and Superior Vena Cava Stenosis. JACC Case Rep. 2020 Oct.2(12):1959-1965. Pubmedid: 34317089. Pmcid: PMC8299245.
• Trejo Bittar HE, Jerome JA, Hartman D, Pantanowitz L, Mehrad M, Dacic S. Prognostic significance of microscopic size in peripherally located scar-associated clinical stage I lung carcinomas. Lung Cancer. 2020 May.143:12-18. Pubmedid: 32200136.
• Saygin D, Tabib T, Bittar HET, Valenzi E, Sembrat J, Chan SY, Rojas M, Lafyatis R. Transcriptional profiling of lung cell populations in idiopathic pulmonary arterial hypertension. Pulm Circ. 2020 Feb.10(1). Pubmedid: 32166015. Pmcid: PMC7052475.
• Wu J, Mady LJ, Roy A, Aral AM, Lee B, Zheng F, Catalin T, Chun Y, Wagner WR, Yang K, Trejo Bittar HE, Chi D, Kumta PN. In-vivo efficacy of biodegradable ultrahigh ductility Mg-Li-Zn alloy tracheal stents for pediatric airway obstruction. Commun Biol. 2020 Dec.3(1):787. Pubmedid: 33339963. Pmcid: PMC7749127.
• Trejo Bittar HE, Monaco SE, Pantanowitz L. Surfactant protein A compared to thyroid transcription factor-1 in identifying metastatic tumors of lung origin in cytopathology. J Am Soc Cytopathol. 2019 May.3(5):261-268. Pubmedid: 31051680.
• Fein AS, Trejo Bittar HE, Shende MR, Scalzetti EM, Ko MW. Castleman Disease Presenting with Pseudotumour Cerebri and Myasthenia Gravis: A Case Report and Literature Review. Neuroophthalmology. 2019 Jun.43(3):185-191. Pubmedid: 31312243. Pmcid: PMC6619924.
• Valenzi E, Bulik M, Tabib T, Morse C, Sembrat J, Trejo Bittar H, Rojas M, Lafyatis R. Single-cell analysis reveals fibroblast heterogeneity and myofibroblasts in systemic sclerosis-associated interstitial lung disease. Ann Rheum Dis. 2019 Dec.78(10):1379-1387. Pubmedid: 31405848. Pmcid: PMC7255436.
• Yoon JH, Nouraie M, Chen X, Zou RH, Sellares J, Veraldi KL, Chiarchiaro J, Lindell K, Wilson DO, Kaminski N, Burns T, Trejo Bittar H, Yousem S, Gibson K, Kass DJ. Characteristics of lung cancer among patients with idiopathic pulmonary fibrosis and interstitial lung disease - analysis of institutional and population data. Respir Res. 2018 Oct.19(1):195. Pubmedid: 30285867. Pmcid: PMC6171146.
• Mehrad M, Roy S, Bittar HT, Dacic S. Next-Generation Sequencing Approach to Non-Small Cell Lung Carcinoma Yields More Actionable Alterations. Arch Pathol Lab Med. 2018 Mar.142(3):353-357. Pubmedid: 29219616.
• Mehrad M, LaFramboise WA, Lyons MA, Trejo Bittar HE, Yousem SA. Whole-exome sequencing identifies unique mutations and copy number losses in calcifying fibrous tumor of the pleura: report of 3 cases and review of the literature. Hum Pathol. 2018 Aug.78:36-43. Pubmedid: 29689243.
• Fajt ML, Birnie KM, Trejo Bittar HE, Petrov AA. Co-existence of vocal cord dysfunction with pulmonary conditions other than asthma: A case series. Respir Med Case Rep. 2018 Aug.25:104-108. Pubmedid: 30101057. Pmcid: PMC6083429.
• Prabhu AV, Kim C, Crihalmeanu T, Hansberry DR, Agarwal N, DeFrances MC, Trejo Bittar HE. An online readability analysis of pathology-related patient education articles: an opportunity for pathologists to educate patients. Hum Pathol. 2017 Jul.65:15-20. Pubmedid: 28504209.
• Trejo Bittar HE, Doberer D, Mehrad M, Strollo DC, Leader JK, Wenzel S, Yousem SA. Histologic Findings of Severe/Therapy-Resistant Asthma From Video-assisted Thoracoscopic Surgery Biopsies. Am J Surg Pathol. 2017 Feb.41(2):182-188. Pubmedid: 28079597. Pmcid: PMC5234856.
• Trejo Bittar HE, Luvison A, Miller C, Dacic S. A comparison of ALK gene rearrangement and ALK protein expression in primary lung carcinoma and matched metastasis. Histopathology. 2017 Aug.71(2):269-277. Pubmedid: 28316074.
• Mehrad M, Trejo Bittar HE, Yousem SA. Sex steroid receptor expression in idiopathic pulmonary fibrosis. Hum Pathol. 2017 Aug.66:200-205. Pubmedid: 28300574.
• Delic JA, Fuhrman CR, Trejo Bittar HE. Pulmonary Alveolar Microlithiasis: AIRP Best Cases in Radiologic-Pathologic Correlation. Radiographics. 2016 Sep.36(5):1334-1338. Pubmedid: 27618319.
• Wang P, Bahreini A, Gyanchandani R, Lucas PC, Hartmaier RJ, Watters RJ, Jonnalagadda AR, Trejo Bittar HE, Berg A, Hamilton RL, Kurland BF, Weiss KR, Mathew A, Leone JP, Davidson NE, Nikiforova MN, Brufsky AM, Ambros TF, Stern AM, Puhalla SL, Lee AV, Oesterreich S. Sensitive Detection of Mono- and Polyclonal ESR1 Mutations in Primary Tumors, Metastatic Lesions, and Cell-Free DNA of Breast Cancer Patients. Clin Cancer Res. 2016 Mar.22(5):1130-1137. Pubmedid: 26500237. Pmcid: PMC4775406.
• Trejo Bittar HE, Pantanowitz L. Merkel Cell Polyomavirus is Not Detected in Lung Adenocarcinomas by Immunohistochemistry. Appl Immunohistochem Mol Morphol. 2016 Jul.24(6):427-430. Pubmedid: 26317307.
• Dewan R, Trejo Bittar HE, Lacomis J, Ocak I. Granulomatosis with Polyangiitis Presenting with Coronary Artery and Pericardial Involvement. Case Rep Radiol. 2016 Jan.2015:516437. Pubmedid: 26798536. Pmcid: PMC4700160.
• Tan J, Tedrow JR, Dutta JA, Juan-Guardela B, Nouraie M, Chu Y, Trejo Bittar H, Ramani K, Biswas PS, Veraldi KL, Kaminski N, Zhang Y, Kass DJ. Expression of RXFP1 Is Decreased in Idiopathic Pulmonary Fibrosis. Implications for Relaxin-based Therapies. Am J Respir Crit Care Med. 2016 Dec.194(11):1392-1402. Pubmedid: 27310652. Pmcid: PMC5148141.
• Helenius IT, Nair A, Bittar HE, Sznajder JI, Sporn PH, Beitel GJ. Focused Screening Identifies Evoxine as a Small Molecule That Counteracts CO2-Induced Immune Suppression. J Biomol Screen. 2016 Apr.21(4):363-371. Pubmedid: 26701099. Pmcid: PMC5096368.
• Doberer D, Trejo Bittar HE, Wenzel SE. Should lung biopsies be performed in patients with severe asthma?. Eur Respir Rev. 2015 Sep.24(137):525-539. Pubmedid: 26324815. Pmcid: PMC9487699.
• Trejo Bittar HE, Yousem SA, Wenzel SE. Pathobiology of severe asthma. Annu Rev Pathol. 2015 Jun.10:511-545. Pubmedid: 25423350.
• Dada LA, Trejo Bittar HE, Welch LC, Vagin O, Deiss-Yehiely N, Kelly AM, Baker MR, Capri J, Cohn W, Whitelegge JP, Vadász I, Gruenbaum Y, Sznajder JI. High CO2 Leads to Na,K-ATPase Endocytosis via c-Jun Amino-Terminal Kinase-Induced LMO7b Phosphorylation. Mol Cell Biol. 2015 Dec.35(23):3962-3973. Pubmedid: 26370512. Pmcid: PMC4628060.
• Trejo Bittar HE, Incharoen P, Althouse AD, Dacic S. Accuracy of the IASLC/ATS/ERS histological subtyping of stage I lung adenocarcinoma on intraoperative frozen sections. Mod Pathol. 2015 Aug.28(8):1058-1063. Pubmedid: 26022456.
• Trejo Bittar HE, Radder JE, Ranganathan S, Srinivasan A, Madan-Khetarpal S, Reyes-Múgica M. Clear cell sarcoma of the kidney in a child with Fanconi anemia. Pediatr Dev Pathol. 2014 Oct.17(4):297-301. Pubmedid: 24735155.
• Lecuona E, Sun H, Chen J, Trejo HE, Baker MA, Sznajder JI. Protein kinase A-Iα regulates Na,K-ATPase endocytosis in alveolar epithelial cells exposed to high CO(2) concentrations. Am J Respir Cell Mol Biol. 2013 May.48(5):626-634. Pubmedid: 23349050. Pmcid: PMC3707378.
• Kamp DW, Liu G, Cheresh P, Kim SJ, Mueller A, Lam AP, Trejo H, Williams D, Tulasiram S, Baker M, Ridge K, Chandel NS, Beri R. Asbestos-induced alveolar epithelial cell apoptosis. The role of endoplasmic reticulum stress response. Am J Respir Cell Mol Biol. 2013 Dec.49(6):892-901. Pubmedid: 23885834. Pmcid: PMC3931115.
• Gusarova GA, Trejo HE, Dada LA, Briva A, Welch LC, Hamanaka RB, Mutlu GM, Chandel NS, Prakriya M, Sznajder JI. Hypoxia leads to Na,K-ATPase downregulation via Ca(2+) release-activated Ca(2+) channels and AMPK activation. Mol Cell Biol. 2011 Sep.31(17):3546-3556. Pubmedid: 21730292. Pmcid: PMC3165547.
• Rogel MR, Soni PN, Troken JR, Sitikov A, Trejo HE, Ridge KM. Vimentin is sufficient and required for wound repair and remodeling in alveolar epithelial cells. Faseb J. 2011 Nov.25(11):3873-3883. Pubmedid: 21803859. Pmcid: PMC3205840.
• Welch LC, Lecuona E, Briva A, Trejo HE, Dada LA, Sznajder JI. Extracellular signal-regulated kinase (ERK) participates in the hypercapnia-induced Na,K-ATPase downregulation. FEBS Lett. 2010 Sep.584(18):3985-3989. Pubmedid: 20691686. Pmcid: PMC2966388.
• Pezzulo A, Castro I, Trejo H, Urich D, Caraballo J, Gutiérrez J, Cano C, Sánchez de León R. [Vasoconstriction is required for edema of contralateral lung after reperfusion injury of one lung]. Invest Clin. 2010 Mar.51(1):53-63. Pubmedid: 20815156.
• Wang N, Gates KL, Trejo H, Favoreto S, Schleimer RP, Sznajder JI, Beitel GJ, Sporn PH. Elevated CO2 selectively inhibits interleukin-6 and tumor necrosis factor expression and decreases phagocytosis in the macrophage. Faseb J. 2010 Jul.24(7):2178-2190. Pubmedid: 20181940. Pmcid: PMC2887258.
• Trejo HE, Lecuona E, Grillo D, Szleifer I, Nekrasova OE, Gelfand VI, Sznajder JI. Role of kinesin light chain-2 of kinesin-1 in the traffic of Na,K-ATPase-containing vesicles in alveolar epithelial cells. Faseb J. 2010 Feb.24(2):374-382. Pubmedid: 19773350. Pmcid: PMC2890192.
• Comellas AP, Kelly AM, Trejo HE, Briva A, Lee J, Sznajder JI, Dada LA. Insulin regulates alveolar epithelial function by inducing Na+/K+-ATPase translocation to the plasma membrane in a process mediated by the action of Akt. J Cell Sci. 2010 Apr.123(Pt 8):1343-1351. Pubmedid: 20332111. Pmcid: PMC2848117.
• Lecuona E, Minin A, Trejo HE, Chen J, Comellas AP, Sun H, Grillo D, Nekrasova OE, Welch LC, Szleifer I, Gelfand VI, Sznajder JI. Myosin-Va restrains the trafficking of Na+/K+-ATPase-containing vesicles in alveolar epithelial cells. J Cell Sci. 2009 Nov.122(Pt 21):3915-3922. Pubmedid: 19808891. Pmcid: PMC2773192.
• Bhattacharya R, Gonzalez AM, Debiase PJ, Trejo HE, Goldman RD, Flitney FW, Jones JC. Recruitment of vimentin to the cell surface by beta3 integrin and plectin mediates adhesion strength. J Cell Sci. 2009 May.122(Pt 9):1390-1400. Pubmedid: 19366731. Pmcid: PMC2721003.
• Comellas AP, Briva A, Dada LA, Butti ML, Trejo HE, Yshii C, Azzam ZS, Litvan J, Chen J, Lecuona E, Pesce LM, Yanagisawa M, Sznajder JI. Endothelin-1 impairs alveolar epithelial function via endothelial ETB receptor. Am J Respir Crit Care Med. 2009 Jan.179(2):113-122. Pubmedid: 18948426. Pmcid: PMC2633058.
• Zhou G, Dada LA, Wu M, Kelly A, Trejo H, Zhou Q, Varga J, Sznajder JI. Hypoxia-induced alveolar epithelial-mesenchymal transition requires mitochondrial ROS and hypoxia-inducible factor 1. Am J Physiol Lung Cell Mol Physiol. 2009 Dec.297(6):L1120-L1130. Pubmedid: 19801454. Pmcid: PMC2793183.
• Urich D, Trejo H, Pezzulo A, Caraballo JC, Gutiérrez J, Castro I, Sánchez-de León R. [Effect of hypocapnia/alkalosis on the fluid filtration rate in isolated and perfused rabbit lungs]. Invest Clin. 2008 Jun.49(2):181-193. Pubmedid: 18717265.
• Vadász I, Dada LA, Briva A, Trejo HE, Welch LC, Chen J, Tóth PT, Lecuona E, Witters LA, Schumacker PT, Chandel NS, Seeger W, Sznajder JI. AMP-activated protein kinase regulates CO2-induced alveolar epithelial dysfunction in rats and human cells by promoting Na,K-ATPase endocytosis. J Clin Invest. 2008 Feb.118(2):752-762. Pubmedid: 18188452. Pmcid: PMC2176184.
• Trejo HE, Urich D, Pezzulo AA, Caraballo JC, Gutiérrez J, Castro IJ, Centeno GR, Sánchez de León R. Beneficial effects of hydrocortisone and papaverine on a model of pulmonary embolism induced by autologous blood clots in isolated and perfused rabbit lungs. Respirology. 2007 Nov.12(6):799-806. Pubmedid: 17986106.
• Briva A, Vadász I, Lecuona E, Welch LC, Chen J, Dada LA, Trejo HE, Dumasius V, Azzam ZS, Myrianthefs PM, Batlle D, Gruenbaum Y, Sznajder JI. High CO2 levels impair alveolar epithelial function independently of pH. PLoS One. 2007 Nov.2(11):e1238. Pubmedid: 18043745. Pmcid: PMC2077933.
• Lecuona E, Trejo HE, Sznajder JI. Regulation of Na,K-ATPase during acute lung injury. J Bioenerg Biomembr. 2007 Dec.39(5-6):391-395. Pubmedid: 17972021.
• Trejo H, Urich D, Pezzulo A, Novoa E, Marcano H, Crespo A, Sánchez de León R. [Effect of using several levels of positive end-expiratory pressure over barotrauma's induced lung injury in a model of isolated and perfused rabbit lungs]. Invest Clin. 2006 Mar.47(1):49-64. Pubmedid: 16562644.
• Crespo A, Novoa E, Urich D, Trejo H, Pezzulo A, Sznajder JI, Livia F, Sánchez-de León R. [Effect of changes in airway pressure and the inspiratory volume on the fluid filtration rate and pulmonary artery pressure in isolated rabbit lungs perfused with blood and acellular solution]. Invest Clin. 2006 Dec.47(4):323-335. Pubmedid: 17176901.

• Title: Targeting Inflammation and Alloimmunity in Lung Transplant Recipients With Clazakizumab
  Award Number: 5U01AI163086-05
  Sponsor: National Cancer Institute (NCI)
  Trejo B. (PD/PI)