Company: CERO
Filing Date: 2025-05-27
Form Type: POS AM
Source: 0001213900-25-047469
Chunk: 156

Company: CERO THERAPEUTICS HOLDINGS, INC.
Filing Date: 2025-05-27
Form: POS AM
Chunk 156
---
 a binding domain that is specific to a targeted antigen. This domain is exposed to the outside of the engineered lymphocyte, where it can recognize the target antigen or antigens. The extracellular target binding domain of CAR-T therapies currently approved by the FDA typically use a single-chain variable fragment (“scFv”), consisting of the heavy-chain and light-chain variable regions of an antibody. |

83

| ● | Extracellular hinge domain. The hinge domain is a small structural component which extends from the outer cell membrane to the antigen recognition domain and provides conformational flexibility to facilitate optimal binding of the antigen recognition domain to the targeted antigen on the surface of the cancer cell. |

| ● | Transmembrane domain. This middle portion of the CAR links the antigen recognition domain to the activating elements inside the cell. The transmembrane domain anchors the CAR in the lymphocyte’s membrane, bridging the extracellular hinge and antigen recognition domains with the intracellular signaling domain and provides critical stability to the CAR. In addition, the transmembrane domain may also interact with other transmembrane proteins that enhance CAR function. |

| ● | Intracellular signaling domain. The other end of the CAR, inside the T cell, is connected to two or more contiguous domains responsible for activating the lymphocyte when the CAR binds to its target antigen. The first, found in almost all CAR constructs, is called CD3ξ. The CD3ξ domain delivers an essential primary signal within the T cell and is the natural basis for activation of these lymphocytes. The current generation of CAR-T configurations generally employ one or more costimulatory domains, such as CD28, to provide enhanced activation signals and augment lymphocyte activity. Together, these signals result in the proliferation of the CAR-enabled T cells and selective cellular destruction. In addition, activated CAR-T cells stimulate the local secretion of cytokines and other molecules that can recruit and activate additional immune cells to increase target elimination. |

The assembly of these core CAR components is depicted in the schematic presented below to which certain non-coding regulatory sequences may be used to augment viral gene expression. Delivery of conventional CAR-T cell therapies involves a single viral vector. Conventional CAR-T cell therapies often utilize a lentiviral vector for the delivery of CAR specific genes. Lentiviral particles offer a well-characterized transduction mechanism and are recognized as efficient and convenient vehicles for gene transfer as they demonstrate broad tropism, or activity, in a wide array of cell types, and can be used to target quiescent, or non