Host Response

What is Host Response?

Host response, also referred to as host gene response or host immune response, is the way a body—human or animal—reacts to internal and external stressors such as infections, trauma, and illness. The way in which the host has been affected by bacteria or other invasive infection triggers immune responses to combat that stressor. Each host’s response is specific and unique, determined by the host’s genetic composition. 

Today, scientists can use these unique expressions to understand whether an invader is bacterial, viral, or parasitic, enabling faster, more accurate diagnoses. 

How Do Host Response Diagnostics Work?

Host response-based diagnostics are a new tool used to identify and monitor infections and other diseases. Unlike traditional diagnostic methods that are designed to detect the presence of a single, specific pathogen, host response diagnostics measure the immune response of the host to the pathogen. 

This difference is critical: traditional diagnostics take a hunt-and-peck approach to identify an illness; host response diagnostics operate through a process of elimination. By identifying a host’s response to a set of stressors, entire categories of potential pathogens can quickly be eliminated from consideration, enabling faster diagnoses.

The host response to an infection involves a complex interplay between the innate and adaptive immune systems. When a pathogen enters the body, the innate immune system detects it and mounts a rapid, non-specific response. This response includes the activation of immune cells, such as macrophages and neutrophils, and the release of cytokines and chemokines, which are signaling molecules that help coordinate the immune response.

The adaptive immune system, which includes B cells and T cells, takes longer to respond to an infection but is more specific. B cells produce antibodies that can bind to and neutralize the pathogen, while T cells can directly kill infected cells.

Host response diagnostics measure various components of this immune response to detect the presence of an infection or monitor disease progression. For example, some host response tests measure the levels of cytokines or other immune signaling molecules in blood samples, while others may measure the expression of specific genes associated with the immune response.

By measuring the host response to an infection, these tests can help differentiate between different types of infections and monitor the effectiveness of treatments. Host response diagnostics may also be used to identify individuals who are at risk of developing severe or chronic infections, which can inform treatment decisions and improve patient outcomes.

Host Immune Response vs. Immune Response

The host immune response is a broad term that encompasses all of the body's reactions to an infection or injury, while the immune response is a specific component of the host response that is focused on eliminating pathogens.

While host immune response is a specific signature of the body’s complex and coordinated set of immunological responses to foreign invaders, immune response is the body's defense mechanism against foreign substances, such as viruses, bacteria, and other pathogens. The immune system is responsible for identifying and destroying these harmful substances, while preserving normal cells and tissues in the body. This is where host response and immune response work closely together. 

The immune system is the first line of defense to an external invader. At this point, the host’s body is managing the invader but there is no specificity on how they manage the invader to this particular host. The way the immune system responds sets up the way the host’s genetically predisposed signature will handle the external invader overall, which is the host immune response. The host response needs the immune system and immune response to determine its signature response.

The Promise of Host Response Diagnostics

Host response diagnostics are a new and emerging diagnostic capability that will offer healthcare practitioners and their patients faster, more reliable, data-driven results that will give healthcare practitioners clear steps to take next to help their patient.

By understanding the signatures’ response, healthcare practitioners will quickly know the category of pathogen they are combatting. This won’t just enable faster and more accurate treatment, it will eliminate the chronic overuse of antibiotics to treat illnesses that aren’t actually bacterial. This overuse or misuse of antibiotics and antifungals has prompted the intertwined global health challenges of antibiotic resistance and antimicrobial resistance — the increasing resistance to medicines that can actually help them fight bacterial infections. To combat these challenges it is imperative that practitioners only prescribe them when necessary; host immune response diagnostics can help them do that.

Biomeme’s Host Response Mission

Biomeme is adamant about the potential of host immune response diagnostics to improve global health. Biomeme’s scientists have over 20 years of research and knowledge related to host response, and we are developing a Host Response Test (HR-B/V) that offers the reliable, detailed results practitioners need to determine a viral or bacterial infection, offering them the data-driven information to determine how to treat a patient.

It is our mission to use this diagnostic tool to empower health practitioners to make faster, more accurate diagnoses that will:

• Combat antimicrobial resistance and antibiotic resistance
• Create healthier communities
• Advance One Health worldwide