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J L Birrien

Publications and source records attributed to J L Birrien.

9 recordsLinked to original sources
PubMed1978

The macrophage, target cell of the synthetic adjuvant muramyl dipeptide.

The mechanism of adjuvant activity of the synthetic glycopeptide N-acetylmuramul-L-alanyl-D-isoglutamine or muramyl dipeptide (MDP) was studied using in vitro plaque-forming cell (PFC) response to sheep erythrocytes (SRBC). Addition of MDP to DBA/2 mouse spleen cell cultures resulted regularly in a 2 to 3-fold increase of PFC numbers/10(6) recovered cells (p less than 0.01). Supernates (SPN) from MDP-stimulated cultures added to standard spleen cell + SRBC cultures brought about even more important increases of PFC numbers (p less than 0.01 to p less than 0.001). SPN from cultures supplemented with MDP alone (without SRBC) were more active than those of cell + MDP + SRBC cultures, and SPN removed on day 3 of culture were more active than those of day 5. This activity of SPN was maintained accross an H-2 histocompatibility barrier. Although pretreatment of spleen cells with anti-theta antigen serum entirely suppressed the anti-SRBC PFC response in spite of the presence of MDP, SPN from these cultures were as active as SPN from normal spleen cell MDP-stimulated cultures. In contrast, pretreatment of spleen cells with specific rabbit anti-mouse macrophage serum entirely suppressed both anti-SRBC response and SPN activity. It was concluded that the target cell for MDP is the macrophage which releases factors ultimately acting on B cells through T cell mediation.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1976

Unrelated delayed hypersensitivity reactions accelerate the recovery of immunological responsiveness of specifically depleted cell populations.

Normal CBA mouse spleen cells were specifically depleted of cells spontaneously reacting to pigeon erythrocytes (PRBC) by two methods, the first allows specific depletion of anti-PRBC thymus derived (T) rosette forming cells (RFC) whereas the second depletes bone marrow derived (B) anti-PRBC hemolytic plaque forming cells (PFC). Depleted populations transferred into lethally irradiated syngeneic recipients and stimulated with PRBC failed to develop any significant response but they normally responded to a stimulation with sheep erythrocytes (SRBC). When spleen cells were taken from mice skin painted with picryl (trinitrophenyl: TNP) chloride 12 days before and the recipients were challenged in the same way and stimulated with PRBC, they become capable of producing a definite response to this antigen. Moreover in these animals, a consistent although low number of cells was found, which simultaneously reacted to both native PRBC and TNP conjugated SRBC. These findings show that unrelated delayed hypersensitivity reactions promote the immunological recovery of specifically depleted cell populations.

Animals↗
PubMed1975

Bispecific cells among IgM and IgG producers during the early phase of primary and secondary responses.

Simultaneous immunization of mice with sheep (SRBC) and horse (HRBC) erythrocytes regularly resulted in the appearance of hemolytic plaque-forming cells (PFC) specific for each type of erythrocyte and also of PFC lysing both types of erythrocytes. After primary stimulation the highest number of bispecific cells (42/10(6) cells) was found among PFC as revealed by the direct procedure (IgM producers). Among PFC enhanced with anti-mouse Fab serum (IgG producers), bispecific cells were less numerous (8/10(6) cells). In preparations enhanced by anti-mouse-gammaFc serum which reveals IgG producers without inhibiting IgM antibody, the number of bispecific PFC equalled the sum of bispecific cells revealed by direct and anti-Fab enhanced procedures. The number of direct bispecific PFC during primary and secondary response was approximately the same, whereas the number of IgG-producing, bispecific PFC increased considerably during the secondary response. Another difference was the time limitation of the appearance of bispecific cells: after primary immunization direct bispecific PFC were detected only on days 3, 4 and 5, but enhanced bispecific PFC were present from day 4 up to day 12. However, during the secondary reaction, bispecific PFC were detected by all three procedures only between days 3 and 6. Studies on the cross-reactivity between SRC and HRBC gave negative results at the humoral level, even when the mice were primed with a minimal amount of both erythrocytes and then two months later, boosted with one of them. Studies at the cellular level showed that after immunization with one antigen, only 0.4 to 0.7 direct or enhanced PFC/10(6) cells could simultaneously lyse both erythrocyte types. Thus, a hundred times more bispecific PFC were constantly found after double immunization of the animals. Moreover, sudden disappearance of all bispecific PFC on the 7th day after secondary stimulation makes it unlikely that all bispecific PFC are simply cross-reacting cells.

Animals↗
PubMed1975

The potentiality of antibody-producing cells. I Bispecific cell occurrence in double stimulated cultures of syngeneic or allogeneic spleen cells of the mouse.

Cultures of spleen cells from Swiss, C57Bl or DBA/2 mice stimulated with 2,4,6-trinitrophenyl (TNP) conjugated sheep erythrocytes (SRBC) were used for studying the in vitro responses to TNP and native SRBC antigens and the frequency of occurrence of cells responding to both antigens. The response was revealed by plating the cultured cells with both native SRBC and TNP-conjugated pigeon erythrocytes (TNP--PRBC). Specific responses were obtained in all the cultures. Bispecific haemolytic plaque-forming cells (PFC) were detected in almost all cultures of individual Swiss mice cells with a frequency of 2-5--14 PFC/10(6) cells recovered. In DBA/2 cell cultures bispecific PFC were found in half the cultures (2-5--8-3/10(6) cells) and in C57Bl cell cultures in 30 per cent of the cultures (7--21/10(6) cells). When cells from individual Swiss mice immunized in vivo with TNP--SRBC were as an allogeneic culture from the 2nd day after immunization in the presence of TNP--SRBC, the frequency of bispecific PFC increased from 8 to 30/10(6) cells. Mixed allogeneic cultures of normal C57Bl and DBA/2 cells yielded high specific responses with regular occurrence of bispecific PFC only when the numbers of cells cultured together was small. However, when allogeneic cells were mixed 24 hours after starting the cultures, all responses were stimulated and bispecific PFC were found in considerable numbers (4--33/10(6) cells). Cross-reactivity between TNP--PRBC and native SRBC antigens was studied by culturing cells with each of the antigens and plating the cells with both, or by immunizing in vivo with SRBC or PRBC and culturing the cells with both antigens from the 2nd to the 5th day after immunization with both antigens. In no instance did bispecific PFC exceed background levels (0-1--0-6/10(6) cells) in these control experiments.

Animals↗
PubMed1975

Properties of bispecific rosette-forming cells. II. --Rosette formation by "educated" T-lymphocytes.

Normal thymus cells transferred into thymectomized and lethally irradiated syngeneic mice responded to stimulation with sheep erythrocytes by rosette formation with these erythrocytes. This response reached a peak on the 7th day and was not associated with any production of circulating antibodies. Rosettes produced by "educated" T-cells were inhibited by anti-theta serum as well as by anti-mouse Fab serum. Simultaneous stimulation of transferred thymocytes with sheep and pigeon erythrocytes provoked the appearance of a minority of cells simultaneously binding both types of erythrocytes. Depletion of B cells contaminating normal thymocyte populatins after passage through anti-mouse Ig coated columns before their transfer in thymectomized and irradiated recipients did not prevent the appearance of simple and double RFC. Moreover, when normal thymocytes or T-cells "educated" by allogeneic stimulation were incubated at 4 degrees C with anti-SRBC and anti-PRBC mouse sera a subsequent incubation at 37 degress of resulted in the dissociation of most passive rosettes formed at 4 degrees. Conversely similar incubation at 37 degrees of rosettes formed by actively immunized cells resulted in capping of about 50% simple and double rosettes. This redistribution of membrane receptors is proposed as a routine test for distinguishing active from passive rosettes.

Animals↗