Normal Adult Spleen Cells Research Articles

Effector and regulatory cells in autoimmune oophoritis elicited by neonatal thymectomy.

(C57BL/6 x A/J)F1 (B6AF1) mice thymectomized between days 1 and 4 of age develop autoimmune oophoritis (D3TX oophoritis) 4 to 6 wk later. Oophoritis can be adoptively transferred to young recipients, and the disease in D3TX mice is prevented by reconstitution with normal adult spleen cells. The present study was further defined the nature of the effector and suppressor cells. Contrary to an earlier report, oophoritis is transferred to syngeneic and not allogeneic recipients. The spleen cells from D3TX mice when stimulated in vitro with Con A, also transfer oophoritis to adult recipients. The effector cells are CD4+: oophoritis transfer is abrogated by CD4 antibody and not by CD8 antibody and C. Spleen cells from D3TX male mice transfer disease less efficiently than female cells, thus endogenous ovarian Ag may be required for activation of effector T cells. T cells from normal adult spleen that suppress D3TX oophoritis also appear to be of CD4+ phenotype. These cells are likely to be derived from adult thymus because adult thymocytes also suppress D3TX disease. We were unable to substantiate the earlier claim that suppressor cells in normal mice are ovarian Ag specific. Thus male and female spleen cells suppress disease with comparable efficiency, and deprivation of endogenous ovarian Ag by neonatal ovariectomy of cell donors had no observable effect on disease suppression.

Preferential rearrangement of V kappa 4 gene segments in pre-B cell lines.

Examination of the in vitro V kappa gene rearrangements of murine adult bone marrow-derived pre-B cell lines reveals that 21 of 25 (84%) cell lines have rearranged a member of the V kappa 4 family. In contrast, analysis of two V kappa cDNA libraries prepared from LPS-stimulated adult spleen cells indicates that only 17% of the Ig kappa cDNAs contain sequences belonging to the V kappa 4 gene family. Half of the pre-B cell lines examined also share an 8-kbp BamHI reciprocal product (rp). However, these rp do not involve the same V kappa gene, indicating that conserved BamHI sites exist 3' of some V kappa genes. This rp is also readily detected in DNA from normal adult spleen cells, suggesting that the in vitro rearrangements examined in this study are representative of kappa rearrangements that occur in vivo. We suggest that, unlike the diverse V kappa repertoire expressed by mature B cells, the germline V kappa segments involved in initial rearrangements of the Ig kappa locus are highly restricted, and that an initial V kappa 4 rearrangement is probably followed by other, more random recombination events.

Inhibition of tumor growth and metastases in mice bearing a malignant fibrosarcoma by T cell-mediated immune response to oncofetal antigens.

ABSTRACT: The presence of fetal antigens on a wide variety of tumors has been well‐documented it has been attributed, for the most part, to de‐repression of genes normally operative in the early stages of embryonic development. Controversy still exists, however, about the role of fetal antigens in antitumor immunity. It is not clear whether the tumor inhibition shown in some systems is due to an immune response. In the present study, conducted in a weakly immunogenic Lewis T241 fibrosarcoma, syngeneic for C57B1/ 6J mice, immunization of normal mice with syneneic fetal cells resulted in striking inhibition of growth and metastases of tumors. On the other hand, immunization with syngeneic normal, adult spleen cells or with allogeneic A/J fetal cells did not inhibit tumor growth or metastases. Mice that had gone through single pregnancy also showed inhibition in tumor growth and metastases. Immunization of female mice with syngeneic tumor cells or fetal cells, prior to pregnancy, resulted in a high incidence of fetal death in these mice. Further studies showed that tumor inhibitory response evoked by fetal cell immunization was due to fetal antigens the male‐specific HY antigen was not responsible for antitumor response. When tumor cells were mixed with spleen cells from fetal antigen‐immunized mice and then injected into normal mice (Winn neutralization assay), significant inhibition of tumor growth and metastases was observed. In this assay, mixing tumor cells with syngeneic fetal cells, normal adult spleen cells, or spleen cells from C57 mice immunized with allogeneic fetal cells did not inhibit the tumor growth or metastases. These results show that inhibition in tumor growth and metastases, following fetal cell immunization, was due to a specific immune response to the oncofetal antigens involved. Analysis of effector cells showed them to be T cells of Lyt‐1+ and Lyt‐2− phenotype.

Neonatally induced tolerance to soluble protein antigens: II. A role for the thymus in prolonging tolerance

Mice were rendered tolerant to bovine serum albumin (BSA) or fowl γ-globulin (FGG) by neonatal injection. Spleen and thymus cells from tolerant mice were able to suppress responsiveness of normal adult spleen cells, but only if tolerant donor mice were between the ages of 6 weeks and the age at which mice were no longer tolerant (10 weeks for BSA tolerance and 20 weeks for FGG tolerance). To determine whether T-cell-dependent suppression was obligatory for the maintenance of tolerance, neonatal nude and euthymic littermate mice were injected with tolerizing doses of FGG. FGG-specific B-cell tolerance in nude mice lasted until the mice were 8 weeks of age. In sharp contrast, B-cell tolerance in euthymic littermates lasted until 22 weeks of age. These results are consistent with a “fail-safe” role of T-cell-dependent immune suppression in the maintenance of tolerance.

Effect of anti-Ia serum in vitro on lipopolysaccharide-induced proliferative responses of murine bone marrow and spleen cells.

The in vitro proliferative response of murine bone marrow cells and spleen cells to bacterial lipopolysaccharide (LPS) and the effect of anti-Ia serum on the response were studied. The incorporation of [3H]thymidine into cells prepared from bone marrow increased in the presence of LPS, but the addition of anti-Ia serum to the cultures reduced the incorporation. Pretreatment of bone marrow cells with anti-Ia serum and complement did not abolish the ability of the cells to respond to LPS, while the same pretreatment destroyed this ability in spleen cells. These results suggest that cultures of Ia-negative bone marrow cells generate Ia-positive cells during the culture period, and the Ia-positive cells are responsive cells to LPS. The proliferative response of 1- or 2-week-old spleen cells was easily suppressed by anti-Ia serum when compared with that of 4-week-old spleen cells. Furthermore, the responses of spleen cells obtained from gamma-irradiated and syngeneic bone marrow cell-reconstituted mice were prominently suppressed by anti-Ia serum in comparison with that of normal adult spleen cells. These findings suggest that LPS-responsive lymphocytes in the developmental stage are quite sensitive to anti-Ia serum. The effect of anti-Ia serum on the maturation of bone marrow-derived lymphocytes was discussed.

Thymic medullary lymphocytes: I. Lymphokines produced by thymic medullary lymphocytes as a second signal for intrathymic stem cell homing

Lymphokines produced by thymic medullary cells (TMC) or by normal spleen cells after allogeneic stimulation have been tested for their chemotactic properties in an in vitro migration test. Lymphokines produced by TMC specifically attract cells from nude spleen or from T-cell-deprived spleen depleted of macrophagic cells, but not from normal adult spleen. Supernatants produced by normal adult spleen cells did not attract any of the cells tested (nude spleen cells, T-cell-deprived spleen cells, or normal spleen cells). These results suggest a role for mature TMC in intrathymic stem cell homing. These cells could deliver a second signal to the stem cell, complementary to those provided by thymic epithelium.

T-Cell-Mediated Antitumor Immune Response Induced by Oncofetal Antigens<xref ref-type="fn" rid="FN2">2</xref><xref ref-type="fn" rid="FN3">3</xref>

The possibility that fetal antigens take part in tumor immunity has been investigated to a limited extent, but the results of these studies have been controversial. It is not clear that tumor inhibition shown in some systems is due to an immune reaction. In the present study, performed in a weakly immunogenic tumor system (Lewis T241 fibrosarcoma in inbred C57BL/6J mice), immunization of mice with syngeneic fetal cells resulted in striking inhibition of growth and metastases of tumors. Mice that had gone through single pregnancies also showed a decreased rate of tumor growth and tumor metastases. Further studies have shown that the tumor inhibitory response evoked by fetal cell immunization is due to fetal antigens, and the male specific HY antigen is not responsible for antitumor response. Injection of tumor cells mixed with spleen cells from mice immunized with syngeneic fetal cells into normal mice resulted in significant inhibition of tumor growth and metastases in the Winn neutralization assay. Syngeneic fetal cells, normal adult spleen cells, or spleen cells from C57BL/6 mice immunized with allogeneic fetal cells did not inhibit tumor growth or metastases. These results show that tumor inhibition following fetal cell immunization is due to an immune reaction and is not due to a nonimmune physiologic process. Further analysis of effector cells showed them to be of the T-cell type.

Analysis of early events occurring during neonatal induction of tolerance to histoincompatible cells in mice

Mice have been analyzed at different times post neonatal inoculation of F 1 hybrid lymphoid cells for their ability to respond to foreign MHC antigens expressed on the tolerizing cell population, and to impart that response phenotype to normal adult spleen cells. At early times following neonatal challenge with F 1 spleen cells all mice produced serum immunoglobulins of F 1 donor origin which inhibited the response of normal adult cells. The antigenic specificity of the inhibitory factors suggests a role for an antireceptor antibody in the inhibition seen, and the presence of such serum-mediated inhibition is indicative of (and may be causally related to) the late appearance of a cell-mediated suppressor mechanism in these mice.

Effect of Immunologic Intervention on In Vivo Murine Rous Sarcoma Virus Tumorigenesis2

The effect of immunologic manipulation on the development of primary murine Rous sarcoma was examined after neonatal injection of Rous sarcoma virus-induced chicken tumor material (RCTM) into mice. Heterologous antithymocyte serum (ATS) treatment of mice beginning at 7 and 21 days of age tripled and nearly doubled, respectively, the incidence of primary Rous sarcoma, but treatment at 21 days significantly prolonged the mean latency period of the resultant tumors. Also studied was the effect of an ip injection of syngeneic adult mouse lymphold cells, either normal or sensitized, on primary Rous sarcoma incidence. Lymphold cells from syngeneic adult mice immunized with allogeneic Rous sarcomas (and resistant to syngeneic tumor challenge) had no effect when the animals received infections at birth (day 1), but immune lymph node cells (LNC) significantly increased tumor incidence when animals were given injections of LNC 1 week after birth and injections of RCTM on day 1. LNC and spleen cells (SC) from syngeneic adult mice that had been inoculated with RCTM at birth but had not developed tumors by 200 days of age (V+T−) decreased tumor incidence when administered on day 1 but not on day 7. Normal adult SC and LNC had no effect when given on day 1 but significantly increased tumor incidence when given on day 7. The tumor-stimulating activity of normal lymphoid cells administered on day 7 of life was observed both in the relatively susceptible strain C57BL/10ScSn mice and the resistant H-2 congenic strain B10.D2. Serum from adult immune, V+T−, and T+ mice administered on days 1 and 7 decreased primary tumor incidence, though only the effect of T+ serum was statistically significant. The offspring of immune mothers were less susceptible than those of normal mothers. The offspring of passively immunized mothers given serum from immune females during pregnancy were more susceptible than controls. RCTM-inoculated mice were apparently susceptible only to immunologic manipulations that reduced primary tumor incidence during the first few days of life. After 7 days of age, all treatments had no net effect or increased tumor incidence, though ATS treatment beginning at day 21 significantly lengthened the mean tumor latency period.

Analysis of B Cell Activation Requirements with TNP-Conjugated Polyacrylamide Beads

Abstract TNP-polyacrylamide beads of varying epitope density were used as antigens to stimulate normal adult spleen cells, neonatal spleen cells, and spleen cells from mice with the CBA/N immune defect. Lymphocytes from immune defective (CBA/N × DBA/2)F1 male mice or normal 2- to 3-week-old (C57BL/6 × DBA/2) F1 mice were unable to respond to TNP-polyacrylamide beads of low epitope density but responded quite well to high density TNP-polyacrylamide beads. Furthermore, immune defective F1 male spleen cells were shown to be unresponsive to TNP-Dextran yet mounted significant responses to TNP-Sephadex, an insoluble analog of TNP-Dextran. Use of an antiserum with anti-Lyb7.1 activity, which recognizes a mature subset of B cells, also pointed to qualitative differences in the stimulatory activities of highly substituted TNP-polyacrylamide beads and lightly substituted TNP-beads. This antiserum was able to inhibit responses to the low epitope TNP-polyacrylamide beads, which presumably activate a mature subset of B cells, but did not block responses to the highly conjugated TNP-beads, which appear to activate both immature B cells and mature B cells. In the course of these studies it became clear that TNP-polyacrylamide bead is not a truly thymus-independent (TI) antigen. Although it is able to stimulate significant responses in nude spleen cells, it is an ineffective immunogen when cultured with cells extensively depleted of T cells.