B7-H3.CD28Z.CART in Solid Tumors

Inclusion Criteria: Eligibility Criteria for Prescreening Purpose of prescreening is to establish B7-H3 expression by IHC performed at Boston Children's Hospital. This can be performed at any time prior to completing the protocol screening process. Participants who meet the following criteria, will be offered participation in the full screening process and protocol enrollment, if eligible: * Participants must have histologically confirmed diagnosis of a solid tumor that is relapsed or refractory for which standard curative measures do not exist or are no longer effective. * Participant must have adequate pre-trial tumor material available to determine B7-H3 status. Tumor tissue from the most recent resection or biopsy of recurrent disease is preferred. If unavailable, tumor tissue from prior recurrences or from the time of initial diagnosis is acceptable. * Age \>=9 months and \<30 years. * Lansky/Karnofsky performance status ≥50% (see Appendix A) * Life expectancy of greater than 12 weeks * Participants who are screened for this trial should be reasonably anticipated to meet the eligibility criteria for enrollment described in Section 3.2 if their tumor is B7-H3-positive. * Ability to understand and/or the willingness of their parent or legally authorized representative to sign a written informed consent document for prescreening. Eligibility Criteria for Enrollment The following criteria are required for initial study enrollment. Once enrolled, participants will need to…