The ethanol extract of Euphorbia aphylla (Family Euphorbiaceae) was evaluated for molluscicidal activities against Biomphalaria alexandrina and Bulinus truncatus, the snail vectors of Schistosoma mansoni and Schistosoma haematobium in Egypt, respectively. It was also tested for the in-vitro schistosomicidal activity against adult worms and the free- living stages (eggs, miracidia and cercariae) of both species. This study showed that this extract has a considerable molluscicidal activity on both snail spp. (LC50 7.6 and 0.013 ppm and LC90 16.6 and 0.038 ppm respectively). B. truncatus is much more susceptible to E. aphylla ethanol extract than B. alexandrina. On the other hand, the conventional synthetic molluscicide niclosamide assayed by the same procedure showed LC50 0.2 ppm and LC90 0.6 ppm for both snails respectively. Consequently the molluscicidal effect of this extract against B. truncatus is much higher than that of niclosamide. The in vitro assay of this extract at concentration of 100 ug/ml showed lethal effect on adult worms of S. mansoni and S. haematobium after 3 days. The LC50 was found to be 60.4 ug/ml and 50.8 ug/ml and LC90 to be 90.4 ug/ml and 88.7 ug/ml for these species respectively. However, this effect is still much less than that of the reference drug praziquantel which gave LC50 0.2 ug/ml for both species and LC90 0.6 ug/ml for both species. The corresponding molluscicidal LC50 of ethanol extract of E. aphylla killed all S. mansoni free living stages (eggs, miracidia and cercariae) after 30, 20 and 40 minutes respectively and killed the same stages of S. haematobium after 20, 15 and 30 minutes respectively. Consequently the possibility of utilizing E. aphylla extract as an alternative natural molluscicide and as a potential source for anti-schistosomal drug especially for S. haematobium should be considered for further investigations.

The ethanol extract of Euphorbia aphylla (Family Euphorbiaceae) was evaluated for molluscicidal activities against Biomphalaria alexandrina and Bulinus truncatus, the snail vectors of Schistosoma mansoni and Schistosoma haematobium in Egypt, respectively. It was also tested for the in-vitro schistosomicidal activity against adult worms and the free- living stages (eggs, miracidia and cercariae) of both species. This study showed that this extract has a considerable molluscicidal activity on both snail spp. (LC50 7.6 and 0.013 ppm and LC90 16.6 and 0.038 ppm respectively). B. truncatus is much more susceptible to E. aphylla ethanol extract than B. alexandrina. On the other hand, the conventional synthetic molluscicide niclosamide assayed by the same procedure showed LC50 0.2 ppm and LC90 0.6 ppm for both snails respectively. Consequently the molluscicidal effect of this extract against B. truncatus is much higher than that of niclosamide. The in vitro assay of this extract at concentration of 100 ug/ml showed lethal effect on adult worms of S. mansoni and S. haematobium after 3 days. The LC50 was found to be 60.4 ug/ml and 50.8 ug/ml and LC90 to be 90.4 ug/ml and 88.7 ug/ml for these species respectively. However, this effect is still much less than that of the reference drug praziquantel which gave LC50 0.2 ug/ml for both species and LC90 0.6 ug/ml for both species. The corresponding molluscicidal LC50 of ethanol extract of E. aphylla killed all S. mansoni free living stages (eggs, miracidia and cercariae) after 30, 20 and 40 minutes respectively and killed the same stages of S. haematobium after 20, 15 and 30 minutes respectively. Consequently the possibility of utilizing E. aphylla extract as an alternative natural molluscicide and as a potential source for anti-schistosomal drug especially for S. haematobium should be considered for further investigations.

Innate immunity has an important role in the protection against malaria. To clarify its effect on non lethal and lethal strain of Plasmodium yoelii, comparison between two groups of C57BL/6 mice infected with 104 parasitized RBCs was performed. Liver and spleen mononuclear cells were isolated and analyzed by flow cytometry. The parasite appeared in blood on day 3 in both strains, with non lethal infection parasitemia reached a peak of 60% on day 14 and mice completely recovered, while in lethal infection parasitemia was 80% on day 7 and mice succumbed to death. In non lethal strain, mice became anemic and the hematocrit percentage returned to its normal value during recovery, while in the lethal strain mice were severely anemic before death. The major expanding cells were found to be TCR Intermediate (TCRint) cells, mainly NK1.1-subset, these TCRint cells were distinguished from conventional T cells of thymic origin. CD4- & CD8- cells increased in both strains. During malarial infection, the population of conventional T cells did not increase and usually associated with thymic atrophy. The present results showed that TCRint cells were intimately associated with the protection against malarial infection in both non lethal and lethal strains but the mice died in lethal infection due to the massive destruction of red blood cells leading to fatal anemia. Abbreviations: TCRint cells: intermediate T cell receptor cells; TCRhi cells: high T cell receptor cells; NKT cells: natural killer T cells.

Innate immunity has an important role in the protection against malaria. To clarify its effect on non lethal and lethal strain of Plasmodium yoelii, comparison between two groups of C57BL/6 mice infected with 104 parasitized RBCs was performed. Liver and spleen mononuclear cells were isolated and analyzed by flow cytometry. The parasite appeared in blood on day 3 in both strains, with non lethal infection parasitemia reached a peak of 60% on day 14 and mice completely recovered, while in lethal infection parasitemia was 80% on day 7 and mice succumbed to death. In non lethal strain, mice became anemic and the hematocrit percentage returned to its normal value during recovery, while in the lethal strain mice were severely anemic before death. The major expanding cells were found to be TCR Intermediate (TCRint) cells, mainly NK1.1-subset, these TCRint cells were distinguished from conventional T cells of thymic origin. CD4- & CD8- cells increased in both strains. During malarial infection, the population of conventional T cells did not increase and usually associated with thymic atrophy. The present results showed that TCRint cells were intimately associated with the protection against malarial infection in both non lethal and lethal strains but the mice died in lethal infection due to the massive destruction of red blood cells leading to fatal anemia. Abbreviations: TCRint cells: intermediate T cell receptor cells; TCRhi cells: high T cell receptor cells; NKT cells: natural killer T cells.

Innate immunity has an important role in the protection against malaria. To clarify its effect on non lethal and lethal strain of Plasmodium yoelii, comparison between two groups of C57BL/6 mice infected with 104 parasitized RBCs was performed. Liver and spleen mononuclear cells were isolated and analyzed by flow cytometry. The parasite appeared in blood on day 3 in both strains, with non lethal infection parasitemia reached a peak of 60% on day 14 and mice completely recovered, while in lethal infection parasitemia was 80% on day 7 and mice succumbed to death. In non lethal strain, mice became anemic and the hematocrit percentage returned to its normal value during recovery, while in the lethal strain mice were severely anemic before death. The major expanding cells were found to be TCR Intermediate (TCRint) cells, mainly NK1.1-subset, these TCRint cells were distinguished from conventional T cells of thymic origin. CD4- & CD8- cells increased in both strains. During malarial infection, the population of conventional T cells did not increase and usually associated with thymic atrophy. The present results showed that TCRint cells were intimately associated with the protection against malarial infection in both non lethal and lethal strains but the mice died in lethal infection due to the massive destruction of red blood cells leading to fatal anemia. Abbreviations: TCRint cells: intermediate T cell receptor cells; TCRhi cells: high T cell receptor cells; NKT cells: natural killer T cells.

Innate immunity has an important role in the protection against malaria. To clarify its effect on non lethal and lethal strain of Plasmodium yoelii, comparison between two groups of C57BL/6 mice infected with 104 parasitized RBCs was performed. Liver and spleen mononuclear cells were isolated and analyzed by flow cytometry. The parasite appeared in blood on day 3 in both strains, with non lethal infection parasitemia reached a peak of 60% on day 14 and mice completely recovered, while in lethal infection parasitemia was 80% on day 7 and mice succumbed to death. In non lethal strain, mice became anemic and the hematocrit percentage returned to its normal value during recovery, while in the lethal strain mice were severely anemic before death. The major expanding cells were found to be TCR Intermediate (TCRint) cells, mainly NK1.1-subset, these TCRint cells were distinguished from conventional T cells of thymic origin. CD4- & CD8- cells increased in both strains. During malarial infection, the population of conventional T cells did not increase and usually associated with thymic atrophy. The present results showed that TCRint cells were intimately associated with the protection against malarial infection in both non lethal and lethal strains but the mice died in lethal infection due to the massive destruction of red blood cells leading to fatal anemia. Abbreviations: TCRint cells: intermediate T cell receptor cells; TCRhi cells: high T cell receptor cells; NKT cells: natural killer T cells.