Subsequent Events	12 Months Ended
Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events In line with the Company’s 2024 strategic direction to focus its resources on HLHS and AD and manage its cash spend, the Company decided to discontinue its previously disclosed clinical trial in Japan to evaluate Lomecel-B^TM for Aging-related Frailty. On February 21, 2024, the Company’s stockholders approved an amendment to the Company’s certificate of incorporation to effect a reverse stock split of its outstanding shares of Class A common stock and Class B common stock at a ratio, ranging from one-for-five (1:5) to one-for-fifteen (1:15), with the exact ratio to be set within that range at the discretion of its Board of Directors without further approval or authorization of its stockholders. The date of the reverse stock split and the ratio has not yet been determined.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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