Banca de DEFESA: KELEN REGINA ASCOLI BALDI

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : KELEN REGINA ASCOLI BALDI
DATE: 20/10/2020
TIME: 14:00
LOCAL: Web Conferência via xxx - xxxx
TITLE:

Comparison between direct immunofluorescence and immunohistochemistry for the diagnosis of Listeria monocytogenes in formalin-fixed paraffin-embedded tissues.

KEY WORDS:

Listeriosis; immunological techniques; animals.

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUMMARY:

Listeria monocytogenes is a bacterium that infect humans and animals and causes a zoonotic disease characterized by encephalitis, septicemia or abortion. Also, listeriosis leads to significant economic losses due to animal death or sacrifice. The aim of this work was to compare the technique of direct immunofluorescence (IFD) and immunohistochemistry (IHC) for the diagnosis of L. monocytogenes in formalin-fixed and paraffin-embedded (FFPE) tissues. A total of 25 tissue blocks from animals with history and/or lesions compatible with listeriosis were selected. For immunohistochemistry, a diluted polyclonal anti-L. monocytogenes serotype 1 and 4 primary antibody  was used, followed by a secondary antibody with polymer kit. For immunofluorescence, the same primary antibody wasused, followed by fluorescein-labeled anti-rabbit IgG secondary antibody. Each samplewas classified according to the immunostaining presence and intensity. From 25 samples, 10 were positive at least for one technique, whereas eight samples were positive for both IHC and IFD with similar intensity. There was strong immunolabeling in samples from bovines experimentally infected with L. monocytogenes ATCC 7644, as well as in nervous tissues from naturally infected ruminants. This study demonstrated that both techniques are efficient to detect L. monocytogenes in FFPE tissues. Using processed biological materials for IFD, instead of fresh samples, is a quite unique technique, since there are few protocols described. However, IFD did not show any difference in sensitivity when compared to IHC, whereas the latter is less expensive and has an easier result interpretation.

BANKING MEMBERS:
Externa à Instituição - MARCIA CRISTINA DA SILVA
Interno - 1756086 - DIOGENES DEZEN
Presidente - 1081425 - TEANE MILAGRES AUGUSTO GOMES