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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the incorporation by reference, in the prospectus constituting a part of this Registration Statement on Form S-3 for the registration of the resale of 9,466,951 shares of the Class A common stock of Atreca, Inc., of our report dated March 11, 2020, relating to the consolidated financial statements of Atreca, Inc. appearing in the Company's Annual Report on Form 10-K for the year ended December 31, 2019.

        We also consent to the reference to us under the caption "Experts" in the prospectus.

/s/ OUM & CO. LLP

San Francisco, California
July 2, 2020

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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM