Development Of Antibody-forming Cells Research Articles

Modulation of the Development of Humoral Immunity by Topically Applied Acetone, Ethanol, and 12-O-Tetradecanoylphorbol-13-Acetate

The effects of topically applied 12-O-tetradecanoylphorbol-13-acetate (TPA), acetone, and ethanol on systemic immune function were analyzed in SSIN mice. A total of one, four, or eight dorsal applications of solvent (50–300 μl/treatment, 2×/week) affected neither the overall cellularity of the spleen nor the relative proportions of splenic cells expressing CD4, CD8, or Ig surface markers. In contrast, overall cellularities of the spleen increased and relative T cell content of the spleen decreased in mice treated multiple times with TPA (2 μg/application in 0.2 ml acetone). The development of splenic B cells secreting IgM against sheep red blood cells (SRBC, a T-cell-dependent antigen) was retarded, and the overall duration of IgM synthesis was decreased, in mice immunized 1 hr after the last of four applications (>200 μl) of either solvent. Comparable retardations occurred in mice immunized as late as 7 days after termination of solvent treatment. However, solvent effects on the development of antibody-forming cells were not observed after eight topical applications or when TNP-LPS (a T-cell-independent antigen) was used as the immunogen. The effects of TPA on the development of IgM-secreting B cells were indistinguishable from those of the solvent used for its application. Although serum hemagglutination titers to SRBC correlated with the relative numbers of splenic B cells producing IgM,in vitroproliferative responses to B and T cell mitogens were not predictive of the effects of solvents or TPA on the development of antibody-secreting cells. Collectively, these studies demonstrate that topically applied acetone and ethanol can systemically modulate humoral immunity and emphasize the need for inclusion of nontreated controls when assessing the potential immunomodulatory activities of agents dissolved in acetone or ethanol.

Development of Antibody-Forming Cells in Follicles of Lymph Nodes of Mice after Continuous Antigenic Stimulation

It was the purpose of the present study to test a hypothesis on the direct differentiation of newly formed memory B cells into antibody-forming cells (AFC) in the follicles of lymphnodes. AFC may develop in follicles when mobile antigen is present at the moment that such memory B cells have completed their differentiation under influence of immune complexes trapped on follicular dendritic cells (FDC). In order to study whether the simultaneous presence of mobile antigen and immobilized immune complexes on FDC alters the normal distribution of AFC in lymph nodes, different immunization protocols with the thymus-dependent antigens trinitrophenylated keyhole limpet haemocyanin (TNP-KLH) and horseradish peroxidase (HRP) were used. Results confirm that, provided that mobile antigen and immobilized immune complexes are present simultaneously, AFC that are normally found in the medulla of the lymph node may also develop in the follicles.

Development of a serum-free medium for in vitro immune responses by using β-cyclodextrin: Demonstration of the requirements for polyamines

A serum-free medium has been developed which is able to support primary antibody responses by cultured murine lymphocytes. This medium is based on RPMI 1640 that is supplemented with β-cyclodextrin, insulin, transferrin, albumin, low density lipoprotein, putrescine and l-alanine as substitutes for fetal calf serum. Omission of anyone of these components resulted in a marked decrease of antibody responses. By employing the serum-free culture conditions, it was clearly demonstrated that polyamines such as putrescine, spermidine and spermine had positive effects on the development of antibody-forming cells. This serum-free medium supported the antibody response to sheep erythrocytes, trinitrophenyl (TNP)-Ficoll or TNP-lipopolysaccharide as efficiently as 10% fetal calf serum-containing medium. In addition, murine lymphocytes proliferated in response to an antigen or a mitogen equally well in these two types of medium.

Alteration of humoral and cellular immunity in manganese chloride-treated mice.

Immunological effects of manganese chloride (MnCl2) were determined in male CD-1 mice injected (ip) daily with MnCl2 (0, 1, 3, or 10 mg/kg) for 4 wk. Liver and spleen weights increased in the 10-mg/kg MnCl2 treatment group. The weights of thymus, kidney, and adrenal glands were not affected by MnCl2 treatment. No significant differences in peripheral erythrocyte or leukocyte counts were observed; however, packed cell volumes decreased in the medium- and high-dose groups. Manganese treatment significantly increased the uptake of [3H]thymidine (3H-TdR) by cultured splenic cells. The lymphoproliferative responses to phytohemagglutinin (PHA) and concanavalin A (Con A) increased at all levels of MnCl2 exposure. No differences in the responses to lipopolysaccharide (LPS) were observed. Mixed lymphocyte responses increased significantly with exposure to 10 mg MnCl2/kg. Another immunological alteration induced by MnCl2 was a dose-dependent immunosuppressive effect on the development of antibody-forming cells. The production of anti-sheep red blood cell antibody (alpha-SRBC) nearly ceased following exposure to 10 mg MnCl2/kg. This effect was apparently reversible, as the number of plaque-forming cells in the 10-mg/kg treatment group increased after MnCl2 treatment had been halted for 2 wk. The alpha-SRBC titer also decreased significantly in the 10-mg/kg treatment group, corresponding to the reduction of antibody producing cells. MnCl2 treatment was immunomodulatory to the reduction of antibody producing cells. MnCl2 treatment was immunomodulatory in male CD-1 mice, as indicated by the increase in mitogen and mixed lymphocyte responses and decrease in antibody production.

Effect of antigen-induced suppressor B cells on development of memory B cells, carrier-specific helper T cells, and antibody-forming cells

This paper studies the presence of an Fc receptor on the surface of antigen-induced suppressor B cells (AISB), their sensitivity to antiproliferative agents, their interaction with other immunoregulator cells and with the precursors of antibody-forming cells (AFC). Mice were used in the experiments and were irradiated in a dose of 8.5 Gy (/sup 137/Cs). The effect of AISB on memory B cells is shown as is the effect of AISB on development of carrier-specific helper T cells. Also presented is the effect of AISB on development of AFC.

Control of B cell proliferation: inhibition of responses to B cell mitogens induced by plasma cell tumors.

A multitude of factors has been described that positively and negatively regulate B cell proliferation. A model system for the study of negative control of B cell function is provided by mice bearing plasmacytomas (PC-mice). In PC-mice, the primary immune response, as measured by development of antibody-forming cells (AFC), is severely suppressed. The present report specifically identifies a block in B cell proliferation as the apparent cause of this reduction in AFC production. Thus, the proliferative response of B cells from the spleens of PC-mice (PC-spleens) was significantly impaired when stimulated with four different B cell mitogens (lipopolysaccharide, Salmonella typhimurium mitogen, anti-mu conjugated to Sepharose, and 8-mercaptoguanosine). Nevertheless, the mitogen-responsiveness of these B cells was recovered when they were segregated by various methods from macrophages. These data suggest that the proliferative ability of the B cells in PC-spleens is inherently normal. In concordance with this conclusion, it was shown that suppressor cells from PC-spleens can block the proliferation of normal B cells derived from nontumor-bearing mice. This inhibition does not require direct cell contact and is mediated via soluble factors. The relevance of these results to previous studies of PC-induced immunosuppression and to the control of normal B cell proliferation is discussed.

Effect of route of immunization on development of antibody-forming cells in hilar lymph nodes.

Studies were designed to compare the effect of the route of inoculation of sheep erythrocytes (SRBC) on the development of antibody-forming cells (AFC) in the hilar lymph nodes of BDF1 mice. The major observation from these studies was that the immunogenicity of low concentrations of antigen was dependent on the route of inoculation. Intratracheal, intravenous, or footpad inoculation of low numbers of SRBC (10(7)) did not stimulate development of AFC in hilar lymph nodes. However, intraperitoneal inoculation of the same concentration of antigen induced an immunoglobulin M AFC response in the hilar lymph nodes. Moreover, both intraperitoneal and intratracheal inoculation of 10(7) SRBC primed the mice for an anamnestic AFC response to a subsequent intratracheal inoculation of 10(7) SRBC. These findings support the hypothesis that presentation of antigen by the local or systemic routes may induce either or both a primary a secondary immune response in the draining lymph nodes of the lower respiratory tract.

Selective effects of methylglyoxal-bis-(guanylhydrazone) on the development of antibody-forming cells in mice

The effects of methylglyoxal-bis(guanylhydrazone) on selected cellular immune functions and on S-adenosylmethionine decarboxylase activity were studied in spleen cells from mice given sublethal doses of this drug. The development of antibody-forming cells was markedly inhibited after administration of methylglyoxal-bis(guanylhydrazone) whereas the functions of cytotoxic effector cells and phagocytes were not affected. The activity of S-adenosylmethionine decarboxylase was found to be greatly increased in spleen cells from mice given the drug, and this increase was 4- to 5-fold greater in nylon wool-adherent cell populations as compared to that in non-adherent cell populations. The uptake of methylglyoxal-bis(guanylhydrazone) was 1.5- to 2-fold greater in nylon wool-adherent cells than in non-adherent cells. These studies suggest that methylglyoxal-bis(guanylhydrazone) selectively affects antibody-forming cells among mouse spleen cell populations.

Cytochemical observations on the development of antibody-forming cells in popliteal lymph nodes by an improved immunoperoxidase method

Precursors of cells forming antibody to horseradish peroxidase (HRP) became detectable in lymph nodes of rats and rabbits after the sensitivity and the specificity of the previously used immunocytochemical procedure were increased. The sensitivity of the method was increased by shortening the time of fixation of the tissue from 24 h to 5 h, and by exposing the antibody in the tissue section to a higher concentration of the antigen for a longer time period than previously. The specificity of the method was enhanced by inhibiting the endogenous peroxidase activity with phenylhydrazine. Five to 8 days after the injection of the antigen, many precursors of plasma cells showed the specific reaction for the antibody in the medulla of the lymph node. Most of the precursor cells were smaller than mature plasma cells and had small, eccentrically located nuclei. The smallest of the precursor cells had the appearance of lymphocytes. From 8 days to several weeks after the injection of the antigen, mature plasma cells characterized by an intense antibody reaction coexisted in the medulla with more weakly stained precursor cells. Lymphocytes, blast cells, and transitional cells containing the specific antibody appeared in germinal centers of the cortex not earlier than 2–3 weeks after the injection of the antigen. From 2–3 weeks to several months after the injection of the antigen, a considerable number of small and medium-sized lymphocytes in the diffuse cortex and in the sinuses contained the anti-HRP antibody. In some animals, a strong antibody reaction occurred in the cytoplasm of these lymphocytes. In other animals, a relatively weak reaction was observed in the perinuclear areas and on the cell surfaces. It is suggested that these lymphocytes may be “memory cells.”

B cell tolerance induced by polymeric antigens. III. Dissociation of antibody formation and memory generation in tolerant mice

Hapten (2,4-dinitrophenyl (DNP))-substituted type 3 pneumococcal polysaccharide (DNP-lys-S3) effectively suppresses both primary and secondary anti-DNP antibody responses to DNP-proteins. The present experiments show that tolerizing doses of DNP-lys-S3 have much less effect on B cell memory (re)generation in three distinct situations: (i) in serial transfers of DNP-protein-primed cells, (ii) in virgin mice tolerized before priming with DNP-hemocyanin, and (iii) in tolerized, hemocyanin-primed mice boosted with DNP-hemocyanin. Under some conditions tolerized mice developed 10-50% of normal memory in the absence of significant antibody formation. Isoelectric focusing analyses revealed that many B cell clones proliferate in tolerant mice, but produce very little antibody until transferred to further hosts. Clones that escape suppression in partially tolerant mice do not appear to be resistant to DNP-lys-S3, when retested. Since there is independent evidence that the generation of B memory cells is less T cell-dependent than the development of antibody-forming cells, these data are best explained by assuming that DNP-lys-S3 blocks lymphocyte cooperation. This would be expected to preferentially suppress antibody formation, and to spare memory generation.

Antibody production in chickens thymectomized as embryos and pigeons thymectomized at hatching.

Studies of the influence of thymectomy 2–3 days prior to hatching in chickens and of thymectomy at hatching in pigeons on antibody formation to sheep red blood cells and BSA have been carried out. Although in prior studies complete or incomplete thymectomy at hatching in chickens failed to influence antibody-forming capacity or the development of antibody-forming cells, thymectomy 2–3 days prior to hatching in chickens significantly depressed development of antibody-forming cells and the production of antibodies. Similarly, thymectomy at hatching in pigeons whose lymphoid system is less mature than that of chickens also depresses antibody-forming cells and antibody responses in the primary but not the secondary response in this species.

Development of Antibody-Forming Cells in Neonatal Mice: Stimulation and Inhibition by Calf Thymus Fractions

Abstract Crude and purified saline extracts prepared from calf thymus glands, as well as two fractions prepared by disc electrophoresis from the purified fractions, were studied as to their effects on development of antibody-forming cells in neonatal mice. Mice injected at birth with microgram quantities of the purified extract or a stimulatory fraction, prepared by disc electrophoresis, had a 10- to 40-fold enhancement in the number of plaque-forming cells when challenged at 1 or 2 weeks of life, as compared with normal animals. There was also an enhancement of spleen size and weight. Another purified fraction, also prepared by disc electrophoresis and previously found to inhibit lymphocytopoesis, markedly suppressed development of antibody plaque-forming cells in the neonatal mice. The effect was relatively temporary, since older mice injected at birth with this fraction responded normally when challenged with the sheep red cells.

DNA synthesis in the development of antibody-forming cells during the early stages of the immune response.

THERE is considerable evidence that antibody-forming cells arise by mitotic division after injection of antigen, and that they continue to divide and produce antibody while differentiating (refs. 1–3 and unpublished work of N. K. Jerne, A. Nordin, C. Henry, H. Funi and A. Koros). According to this view, the many antibody-forming cells present at the peak of an immune response are derived by extensive proliferation from a relatively small number of precursors. It has been suggested, however, that plaque-forming cells which release 19S haemolytic antibody may develop from precursors without division4–6. If this is true it follows that lymphoid tissue must contain a large number of cells capable of being directly “switched on” for synthesis of a specific antibody. Experiments designed to test this point are described here.