Joshua A. Welsh, PhD

Translational Research Scientist

Joshua A. Welsh

My name is Joshua Welsh and I’m a postdoctoral research scientist currently conducting research in Jennifer Jones’ lab within the ‘Laboratory of Pathology‘ at the National Cancer Institute in Bethesda, Maryland.

My main research interest is on small lipid spheres released from cells, called extracellular vesicles (EVs). These small spheres contain proteins and genetic information from the cell they were released from. To date, I have investigated novel ways to detect and analyse EVs as well as their use as markers to diagnose and track the progression of disease. My current research focuses on utilizing EVs as a method for cancer diagnosis and predicting treatment prognosis..

Here you can find information on my research, interests, learning resources for analysis equipment, as well as links and information on software I have written.

Please feel free to contact me by email if you have any questions.

2017 | Pres.
Visiting Postdoctoral Fellow, National Institutes of Health

In the Translational Nanobiology Section I am developing a high-throughput, scalable, clinical pipeline for characterizing extracellular vesicles for their use as biomarkers. This work has required me to develop assays but also develop standalone software for the standardization of results, as well as perform multidimensional data analyses. I have led the planning, conducting, and analysis of experiments along with the writing of several manuscripts. I have also been the day-to-day supervisor of numerous postbaccalaureate and summer student’s lab members.

2016 | 2017
Senior Research Assistant, University of Southampton

Following my PhD thesis, I was funded in-kind by Thermo Fisher Scientific to continue developing a high-sensitivity flow cytometry platform and standardization methods to characterize extracellular vesicles.

2014 | 2015
Tutor, The Brilliant Club

In this role I designed an 8-week course to teach to 2 classes of 14-15-year-old children at schools from underprivileged backgrounds. This initiative, organized by the Brilliant Club, is to help increase the variety of students in STEM fields at the top universities in the UK by having PhD students and postdoctoral researchers teach their specialty. The course that I delivered was on basics of flow cytometry and extracellular vesicles. One of my students was selected for having done outstanding work by peer-reviewed process and had their final project published in the organization’s journal.

2013 | 2016
Lab Demonstrator, University of Southampton

In this position I taught groups of 30 students per week how to perform bacterial transformation and determine whether it was successful or not. I would then mark their experimental write-up of the lab data they produced. I chose to take this position to gain experience in disseminating knowledge to students as well as to gain experience teaching large groups.

2013 | 2017
Doctor of Philosophy, University of Southampton

Thesis title: Flow cytometer optimisation and standardisation for the study of extracellular vesicles as translational biomarkers.

Supervisors: Nicola Englyst, PhD; Judith Holloway, PhD; David Smith, BMBS, DM; James Wilkinson, PhD.

2014 | 2015
PCAP Module 1, University of Southampton
2010 | 2013
Bachelor of Science, University of Leceister

Biological Sciences: Physiology with Pharmacology

2020 | Pres.
Member-at-large, ISEV Executive Board

2019 | Pres.
Chair, ISEV Rigor and Standardization: EV Reference Materials Task Force

2016 | Pres.
Member, ISAC-ISEV-ISTH EV Flow Cytometry Working Group

Currently organize, lead calls, and maintain website for the inter-societal working group of ~26 international researchers seeking to standardize extracellular vesicle analysis and reporting.

2015 | Pres.
Associate Fellow, Higher Education Academy

2014 | Pres.
Member, International Society of Extracellular Vesicles

2014 | Pres.
Member, International Society for Advancement of Cytometry (ISAC)

Regular attendee of CYTO meetings, and participant in the annual cytometry development workshops. Awarded Marylou Ingram Scholarship 2019-2023.

Federal Technology Transfer Award, NCI

For contribution to patents and other intellectual property at NCI.

Top Downloaded Paper 2018-2019, Wiley

Awarded for our article: FCMPASS software aids extracellular vesicle light scatter standardisation having been one of the top downloaded articles in the Cytometry Part A journal.

ISAC Marylou Ingram Scholarship 2019-2023, ISAC

Awarded by the International Society for Advancement of Cytometry, the ISAC Marylou Ingram Scholars Program is a five-year career development program designed to enhance the scientific and leadership experiences of research leaders in the field of cytometry. Being chosen as an ISAC Marylou Ingram Scholar is an indication that you are recognized for your scientific skills, research accomplishments, leadership potential and ability to achieve your career goals.

Outstanding Postdoctoral Fellow, CCR-FYI

Nominated and following interviews of top 5 candidates was awarded the outstanding postdoctoral fellow by the Center for Cancer Research - Fellows and Young Investigator Colloquium (CCR-FYI).

Future of Science Fund Scholarship, Keystone Symposia

Scholarship to attend the Keystone Single Cell Biology Meeting for abstract titled: The development of a scalable extracellular vesicle subset characterization pipeline. Chosen by Timm Schroeder PhD and Berthold Go ̈bgens DPhil.

Federal Technology Transfer Award, NCI

Nominated for significantly contributing to the intellectual property of National Cancer Institute for the 4 patents I have submitted in the preceding year.

Summer Research Mentor Award, NIH

An award to cover the salary of a summer intern to work alongside me in the lab.

2nd Prize for Best Oral Presentations, UKEV

Awarded for my presentation titled: An Accessible Method of Flow Cytometer Scatter Standardisation for EV Analysis, given at the United Kingdom Society for Extracellular Vesicles (UKEV).

Student Travel Award, ISAC

Awarded by the International Society for Advancement of Cytometry to allow me to attend the cytometry development workshop and present a talk titled: ‘Flow Cytometry SSC Collection Angle Can Be Deduced Using Acquisition of Reference Beads with Known Refractive Index’.

International Conference Attendance Fund, University of Southampton

Faculty award to support travel to ISEV 2016 to present a talk titled: ‘Leukocyte microvesicle as fibrosis biomarkers in nonalcoholic fatty liver disease’.

Researcher Links/Newton Award, British Council

Award to support travel costs and allow me to attend the UK-Brazil Extracellular Vesicle and Neglected Tropical Diseases Workshop.

Student Travel Award, ISAC

Awarded by the International Society for Advancement of Cytometry to allow me to attend CYTO 2015 and present a talk titled: A Comparison of Extracellular Vesicle Probe Effectiveness Using Simultaneous Labeling.

International Conference Attendance Fund, University of Southampton

Faculty award to support travel to ISEV 2015 to present a talk titled: ‘A New Fluorescent Probe for Identi- fying Microvesicles’.

Researcher Links/Newton Award, British Council

Award to support travel costs and allow me to attend the UK–Russia Researcher Links Workshop: extra- cellular vesicles – mechanisms of biogenesis and roles in disease pathogenesis.

Young Extraordinary Brits Award: Innovation, Jack Wills

National competition to identify individuals who have significantly contributed to innovation in STEM projects.

Best Overall Final Year Experimental Project, University of Leicester

Awarded for my final year project titled: Do endogenous human platelet-delivered microparticles contain intracellular Ca2+ stores?

1st Year University Scholarship, University of Leicester

Awarded for exceeding the academic entry requirements of the course.

Online webinar, SelectBio

The importance of orthogonal measurement techniques for EV quantification. Invited by Jean-Luc Fraikin, PhD

Institut Curie, Paris, France

Towards evaluating the prognostic potential of extracellular vesicles. Invited by Clotilde Théry, PhD

Pediatric Oncology Branch Seminar, NIH, Bethesda, USA

Towards evaluating the prognostic potential of extracellular vesicles. Invited by Rosandra Kaplan, MD

Flow Cytometry User Group, NIH, Bethesda, USA

Extracellular Vesicle Flow Cytometry: A multiplex to single EV analysis (MtSEA) pipeline. Invited by William Telford PhD

UC Davis, Davis, USA

Extracellular Vesicle Flow Cytometry, Invited by Randy Carney PhD

ISEV Workshop: Open, Reproducible and Standardized EV research, Ghent, Belgium

FCMPASS utilizes MIFlowCyt-EV framework criteria and extracts flow cytometry setting information to allow transparent reporting irrespective of file sharing repository. Invited by: Workshop Committee

MADSSCi-NERLSCD regional ABRF groups meeting, Philadelphia, USA

FCMPASS provides light scatter and fluorescence calibration tools for reporting small particle data in standard units. Invited by: Workshop Committee. Invited by: Joanne Lannigan MS

Tutorial, CYTO2019, Vancouver, Canada

EV standardization. Invited by: John Nolan PhD

61st Annual Danish Society for Flow Cytometry Annual Meeting, Copenhagen, Denmark

Next Generation Extracellular Vesicles Studies for Cancer Research. Invited by: DSFCM Committee

19th Annual CCR Fellows and Young Investigators Colloquium, Rockville, USA

Next Generation Extracellular Vesicles Studies for Cancer Research. Invited by: CCR-FYI Committee

CytoFlex User Group Meeting, Bethesda, USA

Tools for extracellular vesicles analysis using flow cytometry. Invited by: Aleksander Keselman, PhD

Chesapeake Cytometry Consortium, Rockville, USA

Tools for extracellular vesicles analysis using flow cytometry. Invited by: Mehrnoosh Abshari, MSc

Cytometry Development Symposium, San Diego, USA

Development of hyperplexed EV phenotyping assays and software. Invited by: John Nolan, PhD

Nanoscale Flow Cytometry for Cancer, Infection, and Disease, Ottawa, Canada

Developing tools for a multiplex-to-single EV analysis pipeline. Invited by: Vera Tang, PhD & Marc-André Langlois, PhD

ISEV-ISAC-ISTH Satellite Symposium, ISEV, Barcelona

Scatter-based reference materials. Invited by: Marca Wauben, PhD


Welsh J A, Killingswroth B, Kepley J, Traynor T, McKinnon K, Savage J, Appel D, Aldape K, Camphausen K, Berzofsky J A, Ivanov A R, Ghiran I H, Jones J C, A simple, high-throughput method of protein and label removal from extracellular vesicle samples., BioRxiv, doi:10.1101/2020.08.20.260307 [website]

Welsh J A, Jones J C, Small particle fluorescence and light scatter calibration using FCMPASS software., Current Protocols in Cytometry, [In Press]

Welsh J A, van der Pol E, Bettin B A, Carter D R F, Hendrix A, Lenassi M, Langlois M, Llorente A, van de Nes A S, Nieuwland R, Tang V, Wang L, Witwer K W, Jones J C, Towards defining reference materials for extracellular vesicle size, concentration, refractive index and epitope abundance, arXiv, arXiv:2004.09428v1. [website]

Welsh J A, Jones J.C. Tang V A., Fluorescence and light scatter calibration allow comparisons of small particle data in standard units across different flow cytometry platforms and detector settings, Cytometry Part A, doi: 10.1002/cyto.a.24029. [website]

Butement J.T., Holloway P.M., Welsh J.A., Holloway J.A, Englyst N.A., Horak P, West J, Wilkinson J.S., Monolithically-integrated cytometer for measuring particle diameter in the extracellular vesicle size range using multi-angle scattering, Lab on a Chip, 2020, doi: 10.1039/C9LC01182J [website]

Welsh J A, van der Pol E, Arkesteijn G, Bremer M, Brisson A, Coumans F, Dignat-George F, Duggan E, Ghiran I, Giebel B, Görgens A, Hendrix A, Lacroix R, Lannigan J, Libregts S, Lozano-Andrés E, Morales-Kastresana A, Robert S, de Rond L, Tertel T, Tigges J, de Wever O, Yan X, Nieuwland R, Wauben M, Nolan J, Jones, J C., MIFlowCyt-EV: a framework for standardized reporting of extracellular vesicle flow cytometry experiments, Journal of Extracellular Vesicles. doi: 10.1080/20013078.2020.1713526. [website]


Czechowska K., Lannigan J., Aghaeepour N., Back J.B., Begum J., Behbehani G., Bispo C., Bitoun D., Fernández A.B., Boova S.T., Brinkman R.R., Ciccolella C.O., Cotleur B., Davies D., Dela Cruz G.V., Del Rio‐Guerra R., Des Lauriers‐Cox A.M., Douagi I., Dumrese C., Bonilla Escobar D.L., Estevam J., Ewald C., Fossum A., Gaudillière B., Green C., Groves C., Hall C., Haque Y., Hedrick M.N., Hogg K., Hsieh E.W., Irish J., Lederer J., Leipold M., Lewis‐Tuffin L.J., Litwin V., Lopez, P., Nasdala, I., Nedbal, J., Ohlsson‐Wilhelm, B.M., Price, K.M., Rahman A.H., Rayanki R., Rieger A.M., Robinson J.P., Shapiro H., Sun Y.S., Tang V.A., Tesfa L., Telford W.G., Walker R., Welsh J.A., Wheeler P. and Tárnok A. (2019), Cyt‐Geist: Current and Future Challenges in Cytometry: Reports of the CYTO 2019 Conference Workshops , Cytometry Part A, 95: 1236-1274. doi:10.1002/cyto.a.23941. [website]

Clayton A, Boilard E, Buzas E I, Cheng L, Falcón-Perez J M, Gardiner C, Gustafson D, Gualerzi A, Hendrix A, Hoffman A, Jones J, Lässer C, Lawson C, Lenassi M, Nazarenko I, O’Driscoll L, Pink R, Siljander P R-M, Soekmadji C, Wauben M, Welsh J A, Witwer K, Zheng L, Nieuwland R, Considerations towards a roadmap for collection, handling and storage of blood extracellular vesicles , Journal of Extracellular Vesicles, 8:1, dos: 10.1080/20013078.2019.1647027. [website]

Tang V.A., Fritzsche A.K., Renner T.M., Burger D., van der Pol E., Lannigan J.A., Brittain G.C., Welsh J.A., Jones J.C., Langlois M., Engineered Retroviruses as Fluorescent Biological Reference Particles for Small Particle Flow Cytometry , BioRXiv, doi: 10.1101/614461. [website]

Welsh J A, Horak P, Wilkinson J S, Ford V, Jones J C, Smith D C, Holloway J A, Englyst N A, FCMPASS software aids extracellular vesicle light scatter standardisation , Cytometry Part A, doi: 10.1002/cyto.a.23782. [website]

Morales-Kastresana A*, Musich T*, Welsh J A*, Telford W, Demberg T, Wood J C S, Felton E J, Bigos M, Ross C D, Kachynski A, Dean A, Dyke J V, Tigges J, Toxavidis V, Parks D R, Overton W R, Kesarwala A P, Freeman G J, Rosner A, Perfetto S P, Pasquet L, Terabe M, McKinnon K, Kapoor V, Trepel J B, Puri A, Kobayashi H, Yung B, Chen X, Guion P, Choyke P, Knox S J, Ghiran I, Robert-Guroff M, Berzofsky J A, Jones J C, High Fidelity Detection and Sorting of Nanoscale Vesicles in Viral Disease and Cancer , Journal of Extracellular Vesicles, doi: 10.1080/20013078.2019.1597603. [website]

Murillo O D, Thistlethwaite W, Rozowsky J, Subramanian S L, Lucero R, Shah N, Jackson A R, Srinivasan S, Chung A, Laurent C D, Kitchen R R, Galeev T, Warrell J, Diao J A, Welsh J A, Hanspers K, Riutta A, Burgstaller-Muehlbacher S, Shah R, Yeri A, Jenkins L M, Ahsen M E, Dogra N, Gifford S M, Smith J T, Stolovitzky G, Tewari A K, Wunsch B H, Yadav K K, Alexander R P, Wang L, Wu C, Wong D, Galas D J, Keuren-Jensen K, Patel T, Jones J C, Das S, Cheung K, Pico A, Su A I, Raffai R L, Laurent L C, Roth M E, Gerstein M B, Milosavljevic A, ExRNA Atlas analysis reveals distinct extracellular RNA cargo types present across human biofluids , Cell, doi: 10.1016/j.cell.2019.02.018. [website]

Görgens A., Bremer M., Ferrer-Tur R., Murke F., Tertel T., Horn P.A., Thalmann S., Welsh J.A., Probst C, Guerin C., Boulanger C.M., Jones J.C., Hanenberg H., Erdbrügger U., Lannigan J., Ricklefs F.L., Andaloussi S., Giebel B., Optimisation of Imaging Flow Cytometry for the Analysis of Single Extracellular Vesicles by Using Fluorescence-tagged Vesicles as Biological Reference Material , Journal of Extracellular Vesicles, doi: 10.1080/20013078.2019.1587567. [website]


Théry C., Witwer K., et al., Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines , Journal of Extracellular Vesicles, 8:1, 1535750, doi: 10.1080/20013078.2018.1535750. [website]

Welsh J.A., Kepley J., Rosner A., Horak P., Berzofsky J. Jones J.C., Prospective use of high-refractive index materials for single molecule detection in flow cytometry. , Sensors, doi:10.3390/s18082461. [website]

Wiklander OPB, Bostancioglu RB, Welsh JA, Zickler AM, Murke F, Corso G, Felldin U, Hagey DW, Evertsson B, Liang X-M, Gustafsson MO, Mohammad DK, Wiek C, Hanenberg H, Bremer M, Gupta D, Björnstedt M, Giebel B, Nordin JZ, Jones JC, EL Andaloussi S and Görgens A., Systematic methodological evaluation of a multiplex bead-based flow cytometry assay for detection of extracellular vesicle surface signatures , Front. Immunol., doi: 10.3389/fimmu.2018.01326. [website]

Clayton A, Buschmann D, Byrd J B, Carter D R F, Cheng L, Compton C, Daaboul G, Devitt A, Falcon-Perez J M, Gardiner C, Gustafson D, Harrison P, Helmbrecht C, Hendrix A, Hill A, Hoffman A, Jones J C, Kalluri R, Kang J Y, Kirchner B, Lässer C, Lawson C, Lenassi M, Levin C, Llorente A, Martens-Uzunova E S, Möller A, Musante L, Ochiya T, Pink R C, Tahara H, Wauben M H M, Webber J P, Welsh J A, Witwer K W, Yin H, Nieuwland R, (2018) Summary of the ISEV workshop on extracellular vesicles as disease biomarkers, held in Birmingham, UK, during December 2017 , Journal of Extracellular Vesicles, 7:1, 1473707, doi: 10.1080/20013078.2018.1473707. [website]


Ramirez M I, Amorim M G, Gadelha C, Milic I, Welsh J A, Freitas V M, Nawaz M, Akbar N, Couch Y, Makin L, Cooke F, Vettore A L, Batista P C, Freezor R A, Pezuk, J A, Rosa-Fernandes L, Carreira A C O, Devitt A, Jacobs L, Silva I T, Coakley G, Nunes D N, Carter D, Palmisano G, Dias-Neto E., Technical challenges of working with extracellular vesicles. , Nanoscale, 2017, 00, 1–26. doi: 10.1039/c7nr08360b [website]

Welsh J A, Holloway JA, Wilkinson JS and Englyst NA, Extracellular Vesicle Flow Cytometry Analysis and Standardization. , Front. Cell Dev. Biol., 2017, 5:78. doi: 10.3389/fcell.2017.00078 [website]

Welsh J A, Holloway JA, Englyst NA, Microvesicles as Biomarkers in Diabetes, Obesity and Non-Alcoholic Fatty Liver Disease: Current Knowledge and Future Directions. , Intern Med, S6:009, 2014. doi: 10.4172/2165-8048.S6-009 [website]