Thermal sensitivity of innate immune response in three species of Rhinella toads

Autor(es)

Moretti, Eduardo Hermogenes ^[1] ; Monteiro Titon, Stefanny Christie ^[1] ; Titon Junior, Braz ^[1] ; Marques, Fernando Silveira ^[1] ; Gomes, Fernando Ribeiro ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biosci, Dept Physiol, Rua Matao Travessa 14, 101 Cidade Univ, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY; v. 237, NOV 2019.
• Citações Web of Science: 0

Resumo

Immune activity is temperature-dependent and strongly related to thermal biology in ectotherms. Eurythermic, vs stenothermic, species commonly show a broader range of immune responses. Furthermore, the development of behavioral fever in ectotherms is correlated with improved immune function. Although amphibians generally show restricted capacity for thermoregulation in the field, behavioral fever has been documented in the laboratory for several anurans. However, the match between behavioral fever and improved immune response at fever thermal preferendum has still to be determined in these animals. In this study, we investigate the thermal sensitivity of the innate immune response, as measured by the plasma bacterial killing ability (BKA) against Aeromonas hydrophila, in three species of toads from genus Rhinella (R. schneideri, R. icterica and R. ornata) during their breeding season. Moreover, we show lipopolysaccharide-induced behavioral fever for R. ornata. The three species of toads showed an inverted U-shaped pattern of thermal sensitivity regarding BKA, with a high efficiency of immune response at temperatures around their thermal preferendum. The results partially corroborate the hypothesis that immune function is maximized at fever thermal preferendum, given that two of the species showed a maximal BKA performance temperature closer to fever than their normal thermal preferendum. Toads also showed an eurythermic pattern of immune response (large temperature breadth of BKA performance >= 95%; B-95) during the breeding season. This large B-95 encompasses much of the ecologically relevant temperatures, with the exception of those exhibited by two species that maintain activity during winter. Lastly, BKA was commonly suppressed at 37 degrees C, highlighting the importance of choosing ecologically relevant temperatures when conducting in vitro immunological tests. (AU)

• Processo FAPESP: 14/16320-7 - Impactos das mudanças climáticas e ambientais sobre a fauna: uma abordagem integrativa
• Beneficiário: Carlos Arturo Navas Iannini
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático