Immune priming against bacteria in spiders and scorpions?

ABSTRACT
Empirical evidence of immune priming in arthropods keeps growing, both at the
within- and trans-generational level. The evidence comes mostly from work on insects
and it remains unclear for some other arthropods whether exposure to a non-lethal
dose of a pathogen provides protection during a second exposure with a lethal dose.
A poorly investigated group are arachnids, with regard to the benefits of immune
priming measured as improved survival. Here, we investigated immune priming in
two arachnids: the wolf spider Lycosa cerrofloresiana and the scorpion Centruroides
granosus. We injected a third of the individuals with lipopolysaccharides of Escherichia
coli (LPS, an immune elicitor), another third were injected with the control solution
(PBS) and the other third were kept naive. Four days after the first inoculations, we
challenged half of the individuals of each group with an injection of a high dose of E.
coli and the other half was treated with the control solution. For scorpions, individuals
that were initially injected with PBS or LPS did not differ in their survival rates against
the bacterial challenge. Individuals injected with LPS showed higher survival than that
of naive individuals as evidence of immune priming. Individuals injected with PBS
tended to show higher survival rates than naive individuals, but the difference was
not significantperhaps suggesting a general immune upregulation caused by the
wounding done by the needle. For spiders, we did not observe evidence of priming,
the bacterial challenge reduced the survival of naive, PBS and LPS individuals at
similar rates. Moreover; for scorpions, we performed antibacterial assays of hemolymph
samples from the three priming treatments (LPS, PBS and naive) and found that the
three treatments reduced bacterial growth but without differences among treatments.
As non-model organisms, with some unique differences in their immunological
mechanisms as compared to the most studied arthropods (insects), arachnids provide
an unexplored field to elucidate the evolution of immune systems.

Autor:

Dumas Galvez

Yostin Añino
Carlos Vega
Eleodoro Bonilla

Editorial: Estación Científica Coiba AIP
Tamaño: 2.9Mb
Soporte: Digital
Formato: Pdf (.pdf)
Idioma: Ingles