Amaranthus Pollen Allergens: Protein Diversity and Impact on Allergy Diagnosis

Review Article

Austin J Allergy. 2015; 2(1): 1019.

Amaranthus Pollen Allergens: Protein Diversity and Impact on Allergy Diagnosis

Hasnain SM1*, Alsini HA1, Gad El-Rab MO2, AlFrayh AR2 and Alaiya AA3

1Department of Cell Biology, King Faisal Specialist Hospital and Research Centre, Saudi Arabia

2College of Medicine, King Saud University, Saudi Arabia

3Stem Cell & Tissue Re-Engineering Program, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia

*Corresponding author: Hasnain SM, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia

Received: November 24, 2015; Accepted: December 17, 2015; Published: December 21, 2015

Abstract

Allergenic weeds dominate the pollen air flora (> 80%) of Saudi Arabian environment. Two species viz Amaranthus viridis (Av) (Slender or Green Amaranth) and A. lividus (Al) are the most prevalent components of this flora. Although all Amaranthus species appear to be allergenic and a potential cause of respiratory allergy, neither a diagnostic extract nor raw pollen grains for Av is available commercially for comparative study on patients.

Thus, in order to determine IgE mediated sensitization of Av and to observe cross-reactivity patterns with other species, an allergological study was conducted using seven Amaranthus species. Row pollen of 5 Amaranthus species were acquired from two commercial sources (Greer USA, Allergon Europe) while Av & Al pollen was collected indigenously. Allergenic extracts were prepared using pollen grains from both sources in buffered saline. Skin Prick Test (SPT) was conducted on 132 allergic patients using all seven extracts.

Protein separation of all seven Amaranthus species was conducted by SDSPAGE. The results indicate that the species of Amaranthus vary in their protein profiles with a pattern of cross SPT reactivity between the species. However, as the exposure takes place with prevalent pollen form Av and Al, the commercial extracts using species not present in the region may not be fully relevant to the patients for diagnosis and immunotherapy

Keywords: Allergy; Pollen; Amaranthus viridis; Diagnosis; Amaranthus species; Protein diversity

Abbreviations

SDS-PAGE: Sodium Dodecyl Sulphate Polyacrylamide Electrophoresis; AV: Amaranthus viridis; SPT: Skin Prick Test; RAC: Research Advice Council

Introduction

Allergy and Asthma in both children and adult can be caused by many allergenic pollen grains from weeds, trees and grasses [1]. World allergenic pollen flora varies in their nature and quantity from place to place and fluctuates with geography and climate.Bronchial Asthma is very common allergic disease occurring in all age groups, particularly children, all over the world and the trend of asthma prevalence in both developed and developing countries are increasing over the last 30 years [2].

Environmental factors are known to play an important role in the elicitation of asthma in genetically predisposed individuals. Although there has also been an increase in the awareness among doctors to diagnose asthma, a combination of various other factors may also be involved in the increased prevalence of asthma [3]. The soil and climate of KSA was once considered unfavorable for plant growth. A large number of plants have been introduced to the kingdom in recent years [4].

The genus Amaranthus consist of several species. It is an allergenic weed shedding pollen in the air throughout the year in Saudi Arabia with peaks in autumn months. There are a number of Amaranthus species in Saudi Arabia as listed in (Table 1). Each of them, with some synonym, is known by a common name as well. Both, the common and synonymic names are also presented in this table. However, the dominant species on the ground and frequently encountered pollen in the air belongs to A. viridis [5] (Figure 1).