RAST-inhibition studies of the imported fire ant with whole body extracts and venom preparations

Superiority of <i>Solenopsis</i><i>invicta</i> Venom to Whole-Body Extract in RAST for Diagnosis of Imported Fire Ant Allergy

“…In the 29 pa tients studied here, only 48% were RAST-positive when IFAWBE was used as allergen compared with 79% positive results obtained with IFAV. These find ings extend our previous RAST inhibition [14] and CIE [13] studies which showed that IFAV is the aller genic component in IFA preparations and that not all IFAV allergens are present in IFAWBE.…”

“…The nature of the allergenic component of IFAV, however, remains to be iden tified. Our previous CIE and RAST inhibition studies using a synthetic venom alkaloid indicated that al lergenicity does not reside in this component [13,14]. A recent report by Hannan et al [18] suggests that the allergenicity may reside in a phospholipase compo nent of IFAV.…”

“…Findings of such clinical studies are sup ported by results of crossed immunelectrophoretic (CIE) studies in our laboratory, which showed the presence of at least 5 venom components in IFAWBE [13]. Radioallergosorbent test (RAST) inhibition stud ies demonstrated the IFAV specificity of IgE and in dicated that allergenicity resides in venom protein ra ther than the alkaloid component [14], In this report, we present data which support the conclusion that IFAV is superior to IFAWBE in the diagnosis of IFA hypersensitivity using the RAST technique.…”

Stinging insect hypersensitivity: A practice parameter update 2011

“…Although there is no venom extract available for commercial use in patients with suspected fire ant hypersensitivity, whole-body extract is available and contains relevant venom allergens, the effectiveness of which is supported by accumulating evidence. [12][13][14][15][16][17][18] It is generally accepted that a positive intradermal skin test response to insect venom at a concentration of less than or equal to 1.0 mg/mL demonstrates the presence of specific IgE antibodies. [19][20][21][22] Skin testing with fire ant whole-body extract is considered indicative of specific IgE antibodies if a positive response occurs at a concentration of 1:100 wt/vol or less by using the skin prick method or 1:1,000 wt/vol or less by using the intradermal method.…”

Fire ant venom allergy

“…Venom has not yet been developed for sale as a commercial product. Many studies have been reported which compare various commercial extracts to various "venom" preparations by skin testing (5,46,61,82), in vitro IgE testing (5,11,13,14,33,59,82), and immunochemical testing (12, 14, 59). These studies have generally shown significant allergen activity in whole-body extracts, but in many cases the "venom" preparations being used were clearly superior, especially for in vitro testing, since there was less dilution by inactive materials derived from the insect bodies.…”