The Alzheimer’s Society found that roughly 55 million people around the world are affected by dementia. Alzheimer’s disease (AD) is the number one cause of death in the UK, and it ranks 7th as leading cause of death in the United States. But researchers have found that tau antibodies could be the key to new methods of diagnosis and immunotherapy that make early detection of AD easier and more effective to treat. 

While tau proteins are known to be a contributing factor to the symptomology of Alzheimer’s disease, tau antibodies are proving to be instrumental in identifying and binding to tau protein aggregates in the brain. Tau antibodies, especially monoclonal anti-Phospho Tau-217, not only make effective biomarkers, but they could also be valuable in preventing and treating AD.

Identifying Tau Tangles

Tau is a protein found in neurons that contributes to a variety of functions in a healthy brain. However, these proteins are vulnerable to genetic anomalies and drastic changes in their environment. Over time, tau proteins become hyperphosphorylated, creating neurofibrillary tangles (NFTs) that inflame and disrupt the normal function of the neuron. If gone untreated, the increase of these NFTs, sometimes called “tau tangles”, has been seen to cause the type of neurodegeneration and cognitive decline that is commonly associated with AD.

Historically, the focus of Alzheimer’s research has been on β-amyloid plaques, which can be identified through biomarkers and imaging in the same way tau can. The problem some researchers have faced is that the presence of amyloid plaques has not been firmly linked to AD symptoms.

According to Alexis Moscoso, PhD, University of Gothenburg, "the presence of amyloid pathology is not always linked to the presence of cognitive impairment, so that’s a problem for our team’s research. Because if you see your patient has elevated brain amyloid, in general, you cannot conclude that this elevated amyloid is causing the cognitive symptoms your patient is currently having.”

Moscoso explains that tau tangles, identified via positron emission tomography (PET), represent a more specific hallmark strongly correlated with AD symptoms. This yields greater confidence in the diagnosis and fewer false positives and false negatives.

Putting Tau Antibodies to Work 

Over the past decade, tau antibody research has explored the mechanics of tau pathology, using animal and in vitro models to identify potential diagnostic and treatment methods. This research has provided essential insights into the use of tau antibodies in developing biomarkers for early, accurate diagnosis of Alzheimer’s disease.

By detecting abnormal tau proteins in cerebrospinal fluid (CSF) or plasma, they can aid in identifying the disease before significant clinical symptoms appear. Furthermore, tau antibodies can be radiolabeled for use in positron emission tomography (PET) imaging that helps doctors and researchers visualize tau pathology in the brain and understanding the extent or progression of the disease.

Therapeutic Benefits of Tau Antibodies 

In a study published by Yingjun Zhao at Xiamen University in China, an anti-Phospho Tau-217 antibody, called mAb2A7, was used in passive immunotherapy to clear pathological tau from the brains of mice. By binding to tau aggregates, these antibodies were shown to reduce the number of tangles, lessening neurodegeneration, and improving memory and motor function. Functionally, the mAb2A7 antibody “blocked apoptosis-associated neuronal loss and brain atrophy, reversed cognitive deficits, and improved motor function in male tauopathic mice.”

This is just one of many studies working toward the widespread clinical application of tau antibody therapies, and clinical trials have already begun in some cases. For instance, Semorinemab is an anti-tau IgG4 antibody currently in phase 2 of U.S. FDA approval and is being tested for its ability to target and neutralize pathological tau.

The Future of Tau Research 

While there are still hurdles in Alzheimer’s disease research, tau antibodies have been a valuable tool in developing new imaging, diagnosis and treatment methods.

There is a steep learning curve to developing tau antibodies that are both highly specific and broadly effective, but at ICL, we specialize in manufacturing a diverse array of tau antibody isoforms. Our highly purified and specific antibodies are used by researchers worldwide to optimize the efficacy and safety of new therapeutic and diagnostic applications. Alzheimer’s research demands affordable and effective reagents, and ICL is making them accessible worldwide.

With so many affected by neurodegenerative diseases, there is much promise in the work being done by researchers like Moscoso and Zhao. Tau-related immunotherapies are making significant strides and may soon be saving the lives of patients around the world.