_There is definitely a difference in the effect of allergen-specific IgE between men and women. And even result...
_There is definitely a difference in the effect of allergen-specific IgE between men and women. And even results for total IgE suggest there still may be a difference between the sexes. The reason for this difference is unknown,_ Schwartzbaum said.
What the study does provide evidence for, however, is the likelihood that the immune systems of people with respiratory allergies could have a protective effect against this type of brain cancer. The ability to investigate this association over four decades between blood sampling and tumor diagnosis gave the researchers better insight into the relationship between allergies and tumor risk, Schwartzbaum said.
For example, a positive test for elevated concentrations of total IgE was associated with a 46 percent decreased risk for developing a glioma 20 years later compared to samples testing negative for elevated IgE, according to the analysis. That decreased risk was only about 25 percent in samples that tested positive for high levels of total IgE taken two to 15 years prior to diagnosis.
_There may be a trend - the closer the samples get to the time of diagnosis, the less help the IgE is in decreasing the risk for glioma. However, if the tumor were suppressing allergy, we would expect to see a bigger difference in risk near the time of diagnosis,_ Schwartzbaum said.
Schwartzbaum plans to further analyze the serum samples for concentration of cytokines, which are chemical messengers that promote or suppress inflammation as part of the immune response, to see if these proteins have a role in the relationship between elevated IgE levels and lowered tumor risk.
This work was funded by the National Cancer Institute, the National Institutes of Health and a Research Enhancement and Assistance Program grant from Ohio State_s Comprehensive Cancer Center.
Co-authors include Bo Ding, Anders Ahlbom and Maria Feychting of the Karolinska Institutet in Stockholm, Sweden; Tom Borge Johannesen and Tom Grimsrud of the Cancer Registry of Norway; Liv Osnes of Ulleval University Hospital in Oslo, Norway; and Linda Karavodin of Karavodin Preclinical Consulting in Encinitas, Calif.
by The Ohio State University