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                          April 7, 2021

       John Sperzel
       President and Chief Executive Officer
       T2 Biosystems, Inc.
       101 Hartwell Ave.
       Lexington, MA 02421

                                                        Re: T2 Biosystems, Inc.
                                                            Registration
Statement on Form S-3
                                                            Filed March 31,
2021
                                                            File No. 333-254918

       Dear Mr. Sperzel:

              This is to advise you that we have not reviewed and will not
review your registration
       statement.

               Please refer to Rules 460 and 461 regarding requests for
acceleration. We remind you
       that the company and its management are responsible for the accuracy and
adequacy of their
       disclosures, notwithstanding any review, comments, action or absence of
action by the staff.

                                                        Please contact Margaret
Schwartz at 202-551-7153 with any questions.




                          Sincerely,


                          Division of Corporation Finance

                          Office of Life Sciences
       cc:                                              Evan Smith, Esq.