The phagocytic activity of Lumbricus terrestris leukocytes is enhanced by the vertebrate opsonins: IgG and complement C3b fragment.

The effect of the vertebrates opsonins: IgG and complement C3 fragments on phagocytic activity of Lumbricus terrestris leukocytes towards sheep erythrocytes was studied. Sheep erythrocytes were previously sensitized with specific IgG or IgM and coated with one of the third component fragments (C3b, C3bi, C3d) of human complement. Our results show that leukocyte phagocytosis was enhanced by vertebrate IgG and C3b complement fragments but not by IgM and fragment C3d. Because opsonization in vertebrates is related to the presence of receptors on the surface of phagocyte membrane, our results suggest that similar receptors exist on earthworm leukocyte surfaces. These new data strengthen the arguments in favour of the presence of components in Lumbricus terrestris which partially share common structures and functions with components of vertebrate humoral immune reactions.

Evidence of synthesis by Lumbricus terrestris of specific substances in response to an immunization with a synthetic hapten.

Lumbricus terrestris (Annelid, Oligocheta) is capable of cellular- and humoral-specific reactions against natural antigens. Is this earthworm able to elaborate a response of antibody type against a synthetic hapten? L. terrestris have been immunized with conjugates made of one of two different synthetic haptens (400 mw) and a carrier protein: bovine serum albumin (BSA) or keyhole limpet haemocyanin (KLH). The presence of anti-hapten substances in coelomic fluid was tested against each iodinated hapten derivative (125I-hapten). The 125I-hapten-substance complexes were separated from the free derivatives by polyethylene glycol (PEG) 6000 precipitation or by gel filtration. The experiments showed that L. terrestris synthesized specific substances against the immunizing hapten. The importance of the response depended on the carrier protein and on the amount of introduced immunogen. A kinetic study of first and second immunization showed that these substances, elaborated in response to the immunization with the synthetic hapten, were synthesized by cells which kept the immunological memory. These data are discussed in relation to the humoral protection mechanisms already established in the invertebrates.

[Prolonged survival of skin allografts in rats by injection of serum or a serum fraction extracted from pregnant rats]. / Survie prolongée d'allogreffes de peau chez le rat par injection de sérum ou d'une fraction sérique (IRG) extraite de rattes.

This work report the partial purification of an alpha 2-macroglobulin present in the serum of allopregnant rats. Ultrogel filtration followed by immune absorption on different antisera were used giving a single band on polyacrylamide gel electrophoresis. This fraction was able to inhibit in vitro T cell cytotoxic response to allogenic cells. When administered repeatedly to rats it significantly increased the survival of skin allograft. This alpha 2-macroglobulin fraction isolated from allopregnant rats was denominated IRG to its graft rejection inhibitory activity.

[Substances contained in the coelomic fluid of Lumbricus terristris having functions in common with those of some human complement components]. / Mise en évidence de substances contenues dans le liquide coelomique de Lumbricus terrestris, possédant des fonctions communes avec celles de certains composants du complément humain.

In the present work, it was demonstrated for the first time that the coelomic fluid of Lumbricus terrestris contained a substance recognized by human classical convertase. This substance permitted an immune, complement-dependent agglutination response of sheep erythrocytes carrying C3-convertase (EAC142). In addition, substances secreted by coelomic leukocytes possessed an inhibitory activity against human complement: the component C3 was cleaved into a C3b fragment. This result suggests the presence of a system the function of which is C3-convertase-like. We have thus shown that some complement functions, with their natural inhibitors, appear early in evolution. Certain of these functions and structures might be preserved throughout evolution.

[Inhibition of an immune hemolysis reaction in higher vertebrates by a serum fraction (fraction P) from the pregnant Salamandra salamandra L]. / Inhibition d'une réaction d'hémolyse immune chez les vertébrés supérieurs par une fraction sérique (fraction P) de femelle gestante chez Salamandra salamandra L.

Serum "fraction P" from Salamandra pregnant female (containing essentially an alpha 2-macroglobulin) possesses non specific cellular immunosuppressive properties [2]. This fraction has been tested in an immune hemolysis reaction: hemolytic Rabbit IgG + guinea-pig complement + Sheep erythrocytes. This fraction, after incubation with guinea-pig complement, inhibits immune lysis.

[In vitro study of comparative immunosuppressive activity of sera from pregnant women on an in vitro cellular cytotoxic reaction]. / Etude in vitro de l'activité immunosuppressive comparée de sérums de Femmes enceintes sur une réaction de cytotoxicité cellulaire in vitro.

By means of an adaptation of a well-known in vitro cellular cytotoxic reaction we can demonstrate: 1. a strong immunosuppressive non-specific activity of sera from pregnant women; 2. a decrease or an absence of immunosuppressive activity of sera from pregnant women submitted to several spontaneous abortions; 3. we propose a reliable and simple test allowing us to predict the outcome of abortions.

[Separation and study of two serum factors involved in the inhibition of the maternal cytotoxic reaction against embryonic cells in pregnant salamandra (author's transl)]. / Séparation et étude de deux facteurs sériques responsables de l'inhibition de la réaction cytotoxique maternelle à l'égard des cellules embryonnaires, chez la salamandre gestante.

In vitro experiments in pregnant salamanders show a maternal specific cytotoxic reaction against larvae cells and an inhibition of this reaction by maternal serum. The last one is double: non-specific inhibition of maternal cellular reaction and specific protection of embryonic cells. Two fractions have been isolated from maternal serum, with biological properties in cell cultures: the first one is a protein (migrating as alpha2-macroglobulin does) which is implied in non-specific immunosuppression of maternal cells; the second fraction contains an IgM and specifically protects embryonic cells against maternal cytotoxicity.

[In vivo and in vitro study of the effect of pregnant female serum graft rejection in Salamandra salamandra Lin]. / Etude in vivo et in vitro de l'activité du sérum de femelle gestante sur la réaction de rejet de greffe chez Salamandra salamandra Lin.

Serum from pregnant female Salamandra salamandra inhibits the cytotoxic reaction from the mother towards its larvae. Such a serum accelerates the allograft rejection reaction. In vitro studies show that a serum from pregnant female inhibits the cytotoxic reaction of host spleen cells towards epithelial cells of the donor of the graft.

[Influence of the age of the mouse on the effectiveness of stimulation of its defenses by electromagnetic radiation]. / Influence de l'âge de la souris sur l'efficacité de la stimulation de ses défenses par un rayonnement électromagnétique.

Biological effects of microwaves on experimental trypanosomiase in the Mouse depends on the state of development of the animal. In fact such stimulation needs a mature immune system. Nevertheless, the increasing of the molecular immune response is only one of the aspects of protection mechanisms stimulated by such microwaves.

[Changes in Plasmodium berghei berghei in mice maintained at high temperatures]. / Modification de Plasmodium berghei berghei chez la souris maintenue dans une atmosphère chaude.

The study of the evolution of Plasmodium berghei berghei is made in mice kept in a high temperature (35 degrees C) throughout the experiment. Some of these mouse parasites (less than 30%) show a gigantic atypical morphology. In the parasite growing in animals kept at 35 degrees C, the amount of DNA is higher than DNA rate of the parasites growing in control mice (20-22 degrees C). There is no evidence of any relation between the increase of DNA amount and the morphological modification of these parasites.

[Influence of a hot environmental temperature on the evolution of experimental paludism of the mouse with Plasmodium berghei berghei]. / Influence d'une ambiance thermique chaude sur l'évolution du paludisme expérimental de la souris à Plasmodium berghei berghei.

Swiss Mice infected with Plasmodium berghei berghei and maintained in permanence in a hot environmental temperature undergo a chronic infection whereas controls maintained at the laboratory temperature develop always an acute and lethal infection. The hot environmental temperature does not seem to have any action on the pathogenicity of the parasites. Host defences are stimulated.

[The maternal protection reaction against a mother's rejection of her own larva in Salamandra salamandra L]. / Etude de la réaction de protection maternelle contre une réaction de rejet de la mère à l'égard de ses larves chez salamandra salamandra L.

In vitro experiments have shown that maternal spleen cells from Salamandra salamandra are cytotoxic to cells from their embryos. This reaction can be inhibited by maternal serum. In this paper, we show that maternal serum protection acts through two effects: by inactivating spleen cells and by protecting embryonic cells. The more numerous the embryos are in a female, the stronger the protection is. The effect of the maternal serum does not appear to be individual specific.

[In vitro comparison of antigraft protection mechanisms in 2 genera of lumbricians: Eisenia and Lumbricus]. / Etude comparée in vitro des réactions de défense antigreffe chez 2 genres de Lombriciens, Eisenia et Lumbricus.

We sum up our in vitro experiments on allograft reactions in 2 genera of Lumbricians: Eisenia and Lumbricus. In Eisenia, first this reaction is a non-specific humoral one, then it becomes a specific cellular reaction. In Lumbricus the allograft reaction is a specific, mostly cellular one. Nevertheless it interferes with an acquired, specific humoral reaction.

[Body wall allograft reaction between 2 populations of worms (Lumbricus terrestris) from the same biotope origin but one of which lives in a different biotope]. / Réactions aux allogreffes de paroi du coprs, chez Lumbricus terrestris, entre deux populations de Vers de même biotope d'origine, mais dont l'une vit dans un biotope différent

Allografts which are practised between Lumbricus from the same biotope take ad libitum. Allografts are practised between two populations of earthworms from the same source one of which has lived in a new biotope for 12 years. Such allografts are attacked but never resorbed by the host.

[Demonstration and in vitro study of a complex reaction (rejection and facilitation) of the mother towards the embryo in the urodele amphibian Salamandra salamandra L]. / Mise en évidence et étude in vitro d'une réaction immunitaire complexe (rejet et facilitation) de la mére envers l'embryon chez l'Amphibien Urodèle Salamandra salamandra L

Spleen cells from pregnant (but not from non-pregnant) Salamandra salamandra are cytotoxic in vitro for dissociated epidermal cells from their own embryos. Maternal serum inhibits this cytotoxicity. Analogies and differences are stressed in Salamandra salamandra between allograft rejection mechanisms and immune reactions towards embryos. They may contribute to an explanation of the delayed expulsion of embryos.