FISH Method Developed for Analyzing Immune Response

Researchers have developed a method to analyze hundreds of thousands of cells at once using FISH-Flow for concurrent detection of mRNA and protein markers in single cells using fluorescence in situ hybridization (FISH) and flow cytometry. The new protocol currently evaluates immune responses and could lead to faster and more accurate diagnoses of illnesses, including tuberculosis (TB) and cancers.

Researchers at Rutgers University developed the protocol to evaluate multitudes of cells at once for telltale mRNA species and proteins. The procedure currently provides an opportunity to observe how multiple kinds of immune cells are responding to a foreign substance (e.g. antigen), making it possible to detect the presence of disease earlier.

"This new process allows us to see how individual immune cells are reacting in real time without using artificial reagents that alter what the cells are doing when they respond to a foreign substance," said Maria Laura Gennaro, a professor at Rutgers' Public Health Research Institute (PHRI), who led development of the method with senior colleagues Yuri Bushkin, Richard Pine, and Sanjay Tyagi at PHRI. As the protocol could be used to identify indicators of other illnesses, they plan to study applying it to early diagnosis and treatment of various infectious and non-infectious lung diseases and certain cancers.

"This powerful diagnostic technology exploits a person's own immune system to assess their potential for developing a wide range of acute and chronic diseases – including those caused by infectious agents and those resulting from host dysfunction like cancer, asthma, or autoimmune disorders," said David Perlin, executive director of Rutgers’ PHRI.

The procedure can be particularly useful in finding ways to help identify people who are predisposed to developing TB, making it possible to treat them and help reduce the spread of the disease. Nearly 2 billion people worldwide are afflicted with latent TB, but many never develop full-blown TB. Currently, the only way to determine if latent TB is present is through skin and blood tests for immunological response to TB antigens. However, treatment is not widely offered to people with latent TB due to the prohibitive cost.

"If you can have a method that helps you determine who among the people who are latently affected by TB are predisposed to illness, you can target treatment of latent TB to those people and the risk of spread is reduced," Prof. Gennaro said.

The procedure detailed also includes a semi-automated version developed by Gennaro's research group in collaboration with engineers at San Jose, California-based BD Biosciences that makes the method faster and highly reproducible for clinical applications.

The study, by Arrigucci R et al, was published May 18, 2017, in the journal Nature Protocols.