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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

          We consent to the use in this Registration Statement on Form S-1 of our report dated March 15, 2019 relating to the consolidated financial statements of Axcella Health Inc. appearing in the Prospectus, which is part of this Registration Statement.

          We also consent to the reference to us under the heading "Experts" in such Prospectus.

/s/ DELOITTE & TOUCHE LLP

Boston, Massachusetts
April 12, 2019

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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM