Some science behind the scenes

MELISA test

 

A MELISA (Memory Lymphocyte Immunostimulation Assay) test is a blood test that detects Type-IV allergy to metals, chemicals, environmental toxins and molds from one single blood sample. It can also identify active Lyme disease (Lyme Borreliosis). The test does not measure toxicity-that is to say, it will not measure the amounts of a harmful substance in the patient's blood. It measures if the patient is allergic to it.

A MELISA test measures a so-called Type-IV delayed hypersensitivity reaction. In contrast to a Type-I allergy, which is mediated by IgE antibodies and is often tested using an ELISA test, a Type-IV allergic reaction is mediated by T-lymphocytes (or memory lymphocytes) that have had prior contact with a given allergen. In genetically predisposed individuals, an ongoing everyday exposure to allergens can induce the Type-IV hypersensitivity with a resulting allergic reaction.

The test procedure is a cell culture and requires live memory lymphocytes. Lymphocytes are isolated and cultured in an incubator for five days. A portion of the blood is kept intact (unexposed to allergens) to serve as a negative control. A second portion is exposed to a universal allergen, such as Pokeweed, to serve as a positive control. Finally, the third portion of the blood is exposed to the suspected allergen in several different concentrations, to ensure that the conditions in vitro are as similar as possible to the ones in vivo.

 

As an example, if a patient has a suspected allergy to dental amalgams, then the allergens tested for will be the metals most commonly used in dental amalgams, such as mercury, silver, tin, copper and so on.  If a patient has a suspected contact allergy to nickel then the test can be used to test for nickel allergy.  “This is especially useful in individuals who have clinical symptoms (contact dermatitis) but a negative patch test.” The lymphocyte reaction to such an allergen is measured by two separate technologies: one based on the uptake of a radioactive isotope by dividing lymphocytes (proliferation); the other by classical microscopy evaluation (transformation).

The MELISA test is used in occupational medicine and environmental health. In Europe, the test is commonly used in dentistry to test for allergy to dental restorative materials, braces and prostheses.

The test is also used to determine whether metal allergy is a factor behind chronic diseases such as chronic fatigue syndrome and multiple sclerosis. The authors hypothesize that if the immune system is constantly staging an allergic reaction to a metal present in the body, this will alert the HPA axis inducing fatigue-like symptoms.

“A study of 930 fatigue patients showed 62% testing MELISA-positive to metal allergy. Of those who removed the offending metals, 76% improved”.