FZD4 recombinant proteins and antibodies

Frizzled-4 (FZD4) is a member of the Wnt receptor family that primarily activates the Wnt/β-catenin signaling pathway by binding to Norrin. This activation regulates retinal vascular development and the formation of the blood-retina barrier (BRB). FZD4 is highly expressed in tissues such as the retina, inner ear, and heart, and its dysfunction is closely associated with various ocular diseases, including familial exudative vitreoretinopathy.

In recent years, significant progress has been made in developing drugs targeting the FZD4 receptor, primarily focusing on the treatment of ocular diseases. When discussing FZD4-targeted therapies, one cannot overlook the San Francisco-based startup Surrozen Inc. Surrozen has built multiple development pipelines around FZD4, including monoclonal, bispecific, and trispecific antibodies. Its anti-FZD4 monoclonal antibody, SZN-413, entered a co-development agreement with Boehringer Ingelheim at the end of 2022. Other companies entering the FZD4 space include EyeBio. EyeBio developed Restoret, a specific FZD4 agonist designed to improve retinal vascular function by activating the FZD4 receptor. In 2023, the company was acquired by Merck for $3 billion, further highlighting the potential of FZD4 as a therapeutic target for ocular diseases.

Despite the promising potential of FZD4 in treating ocular diseases, several challenges remain. First, the receptor has a complex structure, and the lack of high-resolution structural information limits small-molecule drug design. Second, FZD4 expression and function may vary across tissues, requiring careful consideration of tissue specificity during drug development. Additionally, FZD4 agonists may excessively activate the Wnt signaling pathway, leading to uncontrolled cell proliferation, so precise modulation of their activity is necessary.

To support the development of FZD4-targeted therapies, DIMA BIOTECH now offers a full range of FZD4-related products and services. Products include active FZD4 protein, full-length FZD4 membrane protein, and FZD4 FC-validated antibodies. The full-length FZD4 membrane protein retains the receptor’s native structure and is an ideal option for small-molecule drug screening. Services include custom antibodies against proteins from multiple species, antibody humanization, and affinity maturation. Furthermore, to accelerate the development of FZD4 biologics, DIMA BIOTECH has established a FZD4 single B cell seed library, allowing lead antibodies to be obtained in as fast as 28 days. Several FZD4 lead molecules have already been screened, and clients can access them for functional evaluation the next day.