Characterization and production of IgY antibodies anti-Photobacterium damselae subsp. piscicida: Therapeutic and prophylactic use in Rachycentron canadum

Highlights

• IgY anti-Photobacterium damselae subsp. piscicida as prophylactic and therapeutic.

• IgY effectively inhibited the dissemination of anti-Photobacterium damselae subsp. piscicida in Rachycentron canadum.

• Developed an immunohistochemistry assay with highly specificity and affinity for the Photobacterium damselae subsp. piscicida.

Abstract

Pseudotuberculosis is caused by Photobacterium damselae subsp. piscicida (Phdp), an important pathogen in marine fish culture. In this study, Phdp isolated from a Rachycentron canadum farm was used to produce anti-Photobacterium damselae IgY and its protective effect were evaluated in R. canadum challenged with the homologous strain. The IgY was obtained from egg yolks of White Leghorn hens using polyethylene glycol precipitation method. Anti-Phdp IgY showed strongly specific reaction against Phdp proteins. Finally, it was performed the antibody efficacy in vivo to determinate their prophylactic and therapeutic effects during sepsis in R. canadum. For this, fish received anti-Phdp IgY 48 h and 15 days before the challenged with the homologous bacteria of Phdp. In these groups, it was observed less liver and kidney lesions comparing to control group, which was also correlated to the biochemical profile. In this study, it was also developed an immunohistochemistry test that presented highly specificity and affinity to Phdp that could be used as screening method for the diagnosis and analysis of pathogenesis of this disease. It was concluded that the IgY produced effectively inhibited the dissemination of this bacteria that could be helpful for the treatment and prophylaxis of this disease.

Introduction

Marine fish bacteria are a serious issue in fish farm industry due to the high risk of disease transmission, fish mortality, and economic losses (Dunn et al., 1990; Shimada et al., 2014). Photobacterium damselae subsp. piscicida (Phdp) is the causative agent of acute septicemia, pseudotuberculosis or pasteurellosis in marine fish (Tsai et al., 2015).

Antibiotics are commonly used in the feed or added into the water to control this disease. However, the misuse of these substances results in drug residues in fillet, increase bacterial resistance (Syed et al., 2012), changes in the aquatic microbial populations and fish immune system (Zhang et al., 2010). Live attenuated vaccines and bacterins of membrane and/or cytoplasm proteins provide limited protection against this disease and have high production cost (Barnes et al., 2005; Gudding et al., 2014).

Chicken egg yolk immunoglobulin (IgY) antibodies are environment friendly and, unlike antibiotics, elicits no undesirable side effects, disease resistance, or occurrence of toxic residues (Coleman, 1999). The production of IgY is relatively inexpensive, can be produced in large quantities and it is not necessary to sacrifice the hen to obtain it (Chacana et al., 2004). One egg produces on average 100 mg of IgY in the yolk, in 30 days it can reach more than two grams per hen (Carlander, 2002).

IgY therapy is largely used in diseases of mammals as in the diarrhea of post-weaning pigs by E. coli, gastric ulcer by Helicobacter pylori, distemper in dogs, and against toxins of venoms animals (Carlander, 2002; Chacana et al., 2004). In fish, there are reports of the use of anti-Edwarsiella sp. IgY administered directly into the water that protected Japanese eel (Hatta et al., 1994) and anti-Yersinia ruckeri IgY administered in the feed that protected rainbow trout against the experimental infection of the homologous bacteria (Lee et al., 2002). It was also reported that an intra-coelomic administration of anti-Vibrio anguillarum IgY protected rainbow trout against the challenged of V. anguillarum with 83% of survival rate in the treated group compared to 18% in control group (Arasteh et al., 2004). Some studies have highlighted the efficiency of hen IgY as biomarkers for the diagnosis of infectious diseases (Chalghoumi et al., 2009; Fernandes et al., 2019) and neoplasms (Xiao et al., 2008).

R. canadum (cobia) is an important fish in marine aquaculture due to presents fast growth rate, good market demand, feed conversion rate, and easy adaptation to captivity (Shimada et al., 2014). Thus, develop diagnostic biomarkers and studying the pathophysiology of Photobacterium damselae in R. canadum are important for a better understanding of this disease (Remuzgo-Martínez et al., 2014). The aim of this study was to characterize and produce a specific anti-Photobacterium damselae subsp. piscicida IgY and determinate their prophylactic and therapeutic effects against the homologous bacterium on experimental infection of Rachycentron canadum. It was also developed an immunohistochemistry assay for this experiment that could be used as screening method to detect this bacterium.