Biomphalaria tenagophila: dominant character of the resistance to Schistosoma mansoni in descendants of crossbreedings between resistant (Taim, RS) and susceptible (Joinville, SC) strains

Section: Discussionmentioning

confidence: 99%

“…Rosa et al (2005) found that two dominant genes determine resistance in B. tenagophila. In the same year, El-Khayat et al reported that genetics is one of the most important approaches for biological control of susceptibility of B. alexandrina to S. mansoni infection.…”

Section: Discussionmentioning

confidence: 99%

Inheritance of Schistosoma mansoni infection incompatibility in Biomphalaria alexandrina snails

Abou-El-Naga

Eissa

Mossallam

et al. 2010

“…In addition, the mortality of B. tenagophila Taim was higher than that of the other snails. It has been well established that B. tenagophila Taim is completely resistant to S. mansoni (Corrêa et al 1979, Santos et al 1979, Bezerra et al 1997, 2003, Martins-Souza et al 2003, Rosa et al 2004, 2005, Barbosa et al 2006, Pereira et al 2008. Table II shows that B. tenagophila Taim kills sporocysts more effectively than the Cabo Frio strain or B. glabrata.…”

Section: Discussionmentioning

confidence: 99%

“…Biomphalaria glabrata, Biomphalaria tenagophila and Biomphalaria straminea are the three species responsible for the transmission of schistosomiasis in Brazil (Paraense 1975). Many authors (Corrêa et al 1979, Santos et al 1979, Bezerra et al 1997, 2003, Martins-Souza et al 2003, Rosa et al 2004, 2005, Barbosa et al 2006, Pereira et al 2008 have described the existence of a geographic lineage of B. tenagophila (provided from Ecological Station of Taim, state of Rio Grande do Sul, Brazil) resistant to S. mansoni. This lineage represents an important population in which to study the defence mechanisms of these invertebrate hosts to S. mansoni infection.…”

mentioning

confidence: 99%

Interaction between primary and secondary sporocysts of Schistosoma mansoni and the internal defence system of Biomphalaria resistant and susceptible to the parasite

Mattos

Martins-Souza

Kusel

et al. 2011

Self Cite

“…Granath and Yoshino (1984) working with susceptible M-line albino B. glabrata that received serum from resistant 10-R2, obtained more than 60% of protection against S. mansoni. Rosa et al (2005) showed that F1 generation of B. tenagophila generated by crossbreeding from B. tenagophila Taim and B. tenagophila Joinville (albino) were almost 100% resistance to the LE strain of S. mansoni.The plasma of B. glabrata and other planorbid pulmonates contains factors which agglutinate mammalian …”

mentioning

confidence: 99%

Compatibility of Biomphalaria tenagophila with Schistosoma mansoni: a study of homologous plasma transference

Coelho

Bezerra

2006

This study aims to investigate the importance of the serum factors present in the plasma of resistant Biomphalaria tenagophila snails, when transferred to susceptible conspecific. Susceptible B. tenagophila (CF) received plasma from resistant B. tenagophila (Taim), and both were later infected with Schistosoma mansoni. We noticed that the plasma transfer showed an increase on the resistance of susceptible snails of about 86% when compared to the nonimmunized group (p < 0.001).Key words: Biomphalaria -Schistosoma mansoni -plasma Among the endogenous factors involved in snailtrematode interaction, the most important is in relation to the gastropods defense system. This system is different from the vertebrate immune system, as the lymphocytes, immunoglobulins specific antigen are lacking. Nevertheless, the differentiation between the "self" and the "not self" is kept (Bayne 1983). The defense system is made by cellular and humoral elements. The cellular defense system is operated by hemocytes (moving cells), which have phagocytic capacity. The humoral immunity is measured by lectins and opsonins, which are proteins synthesized by hemocytes with specific affinities with carbohydrates (Zelck et al. 1995). Bayne et al. (1980) showed the serum transfer effect of resistant Biomphalaria glabrata on the increase of phagocytic capacity of hemocytes from susceptible snails, demonstrative of interaction between plasmatic factors and the hemocytes during the encapsulation and phagocytic process, that occurred few hours after the miracidium penetration. Although the model B. glabrata/S. mansoni has been the object of several studies, the association B. tenagophila/S. mansoni is also a very interesting model because it shows absolute resistance of the snail to the parasite (Coelho et al. 2004). The aim of this study was to evaluate the occurred changes after plasma transference from resistant to susceptible B. tenagophila snails following infection with Schistosoma mansoni.All snails used came from Brazil. sically the same used by Granath and Yoshino (1984), with minor changes, briefly: all B. tenagophila Taim and Cabo Frio strains were anesthetized with sodic pentobarbitol (Nembutal®), 100 mg/2ml) (Martins-Sousa et al. 2001), for 6 h, to relax all the musculature. The plasma for the transference was collected from a hemolymph pool of five B. tenagophila -Taim snails. After centrifugation of 80 g for 10 min to remove all the hemocytes, it was diluted in sterile PBS in 1:2 proportion. The B. tenagophila -Cabo Frio were inoculated with 5 µl of the diluted serum in the cephalopodal region using a 25 µl Hamilton Microliter® syringe. The control groups B. tenagophila (Taim and Cabo Frio) received the same volume of sterile PBS. Twenty-four hours later, the three groups were individually infected with ten S. mansoni miracidia. Six hours later, the groups were replaced in separate aquariums with aeration by pumping and fed with lettuce ad libitum. All the groups were once a week analyzed concerning the cercarial release up to 60 days ...