Aerobiological, clinical and immunobiochemical studies on Lantana camara pollen and cross-reactivity with other Verbenaceae pollen species

Airborne pollen is an important and potent source of aeroallergens. The aim of the study was to conduct a 2-year aerobiological survey in Calcutta, India, for knowing the concentration and seasonal periodicity of Lantana camara (LC) pollen. The sensitization due to this pollen among seasonal respiratory allergic patients and its chemical composition was studied. An aerobiological survey was conducted with a volumetric Burkard sampler from 2004 to 2006. Protein components of LC pollen were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and IgE immunoblotting. Allergenic activities were determined by in vivo (skin prick test) and in vitro (enzyme-linked immunosorbent assay. In vitro inhibition tests were performed to evaluate cross-reactivity. LC pollen was present from March to May and from September to December contributing up to 10.5% to the total aeropollen load during peak month. Horizontal profile showed highest concentration for nearest (0.5 m) rotorod and it was decreased by half in a distance within 4.5–6.5 m from plot edge. LC pollen contained 7.5% carbohydrate, 19.3% lipid with proline and valine as dominant amino acid. Among 1,500 adult respiratory allergic patients tested, 7.93% showed higher level of positive reaction. IgE binding proteins of 22, 42, 45 and 95 kD were revealed. LC pollen showed remarkable cross-reactivity with other local Verbenaceae pollen taxa (Clerodendron viscosum, Tectona grandis and Vitex negundo). This is the first study on LC pollen regarding its aerobiological, clinical and immuno-biochemical aspects; it should be helpful for the diagnosis and therapy of patients susceptible to LC pollen.