Scientists have created a way of measuring the possibility of affectation in a patient from a single drop of blood, published in the current new journal Technology.
To test whether an individual’s body tissue contains certain pathogens, doctors assess neutrophil chemotaxis, the process whereby neutrophils, the most common type of white blood cell, direct their movement as a response to certain chemical cues in their surroundings. These neutrophils have various receptors on their cell surface in order to detect the chemicals produced by affected cells or other white blood cells already at the site.
As a result, these highly motile cells are attracted to areas of inflammation or pathogenic populations, leaving the blood to enter body tissue, and are typically used as the first line of strength by the body while recruiting other types of immune cells to come to their aid via chemical signals.
Once at the site, neutrophils may operate in several ways to eliminate pathogens: either by phagocytosis, the ingestion and digestion of microbes through hydrolytic enzymes or reactive oxygen species, the release of proteins with antimicrobial properties, or by the creation of a “net-like” structure that traps and eliminates pathogens outside the cell. To assess the possibility of a condition, doctors currently use absolute neutrophil counts, a simple assay of the number of neutrophils measured in the blood. A normal count may consist of over 1,500 cells per microliter of blood. The number of the count, controls the chance of a pathogenic presence in the body, as the neutrophils have left the blood system to enter tissue to help it.
However, should the neutrophils be unable to migrate, or migrate incompletely, the count may inaccurately represent what was occurring within the body, with the team citing burn-related maladies showing improper chemotaxis despite the necessity for neutrophils to be at certain sites to prevent various conditions from developing.
This led to Dr. Daniel Irma, assistant professor at the BioMEMS Resource Center at Massachusetts General Hospital and co-author of the paper, to believe neutrophil count may be insufficient when assessing the possibility of certain pathogen-derived conditions. Furthermore, the current methods to assess neutrophil chemotaxis are time inefficient and require large quantities of blood and skilled medical staff to complete the procedure.
In order to improve these shortcomings, the researchers in Massachusetts developed a silicon-based “microfluidic device” that is capable of assessing neutrophil movement without the constraints imposed by current methods. Using a single drop of blood, the scientists are now capable of measuring chemotaxis directly within a couple of minutes, meaning patients might receive the appropriate precautions depending on their condition in a reduced time frame. Thus, the new procedure measures the direction of their movement, even if this is limited.
In order to ensure their new test was accurate, they sampled blood from three sources: a drop from a finger prick, venous blood and via samples used in current methods. All three showed the neutrophils consistently moving in the same direction at the same speed, indicating that this new blood test may be extremely useful in the prevention and treatment of several conditions.
How does this scientific progress impact humanity?