Unique Gene Expression Profiles Recorded in Adults with Allergic Rhinitis

Amanda J. Cox, PhD

A new case-control study that compared gene expression profiles in adults with allergic rhinitis and those without found that distinct differences in blood and nasal mucosa samples were observed in the former.

The upper respiratory disease is estimated to affect between 10% and 30% of the global population, with significant medical and economic burdens.

Investigators led by Amanda J. Cox, PhD, Menzies Health Institute,Griffith University, felt the results of the study provided evidence for a close interaction between the local site and systemic immunity.

They added that multiplex gene expression analyses have been effective in gaining a global representation of the cellular mechanisms behind complex disease such as allergic rhinitis.

As such, Cox and colleagues applied gene expression technology to identify genes specific to allergic rhinitis and characterize immune-gene expression profiles of nasal mucosal and peripheral blood samples of participants with the disease compared with a healthy cohort.

The Study

The study was designed as a cross-sectional study with a total of 69 participants, 45 of whom were adults with existing allergic rhinitis.

Each participant attended a screening appointment at the Queensland Allergy Services Clinic in Southport for evaluation of allergen sensitization and other clinical characteristics.

The severity of symptoms were evaluated using a collection of self‐reported symptom surveys completed before sample collection

Eligible participants were then asked to refrain from the use of all intranasal and immune modulating medications for 14 days before follow-up appointments.

After the 14-day period, participants attended an appointment at the Clinical Trial Unit at Griffith University for provision of blood and nasal mucosal samples.

Immune gene expression analysis of nasal cell lysate and extracted RNA from blood was performed using a commercially available NanoString nCounter PanCancer Immune Profiling panel (NanoString Technologies)

The Findings

Investigators reported that in total, 175 genes were differentially expressed between the AR and CG cohorts based on p < .05 and 113 genes were differentially expressed after controlling for false discovery rate (FDR).

Though both groups were matched in key physical attributes, the allergic rhinitis group had significantly higher white blood cell, lymphocyte, eosinophil, and basophil counts compared with the control group.

Regarding nasal lysate, a total of 63 genes were differentially expressed between the 2 groups featured in the study, based on p < .05 and 14 genes were differentially expressed after controlling for FDR.

Cox and investigators added that a key finding of the study was that the large proportion of differentially expressed genes in blood samples from those suffering from allergic rhinitis compared with the control group.

A total of 113 differentially expressed genes were identified in blood samples, which represented over 24% of genes that were expressed above background. They believe this indicated that the gene‐expression profiles of blood samples from allergic rhinitis sufferers was “vastly different” from that of the control samples.

Cox and colleagues felt this new data could be integral in the establishment of new, effective therapies.

“The AR‐specific genes and pathways identified in this study have the potential to be targeted in new drug therapies for the reduction of AR symptoms and as markers to evaluate the effectiveness of systemic and topical AR drugs,” the team wrote.

The study, “Adult allergic rhinitis sufferers have unique nasal mucosal and peripheral blood immune gene expression profiles: A case–control study,” was published online in Immunity, Inflammation and Disease.