Detection of antigen-specific suppressor T cell factor by sandwich radioimmunoassay using two monoclonal antibodies with different specificities

We established a sandwich radioimmunoassay using two monoclonal antibodies specific for the distinct allotypic determinants on heavy and light chains of antigen-specific suppressor T cell factors (TsF). By use of this assay system, we confirmed our previous findings that the allotypic determinants (Ct) detected by BALB/c anti-CB-20 (7C5 and 7D1) were shared in various TsF with different antigen specificities, and also that the genes coding for the Ct determinants were indicated to be located on the right side of the Igh-V gene cluster, because the assay system equally detected either KLH-TsF or OVA-TsF from Ighb mice, such as C57BL/6, CB-20 and BAB-14, but not from BALB/c or C3H with other Igh allotypes. Furthermore, the radioimmunoassay, when used with two different anti-Ct (7C5 and 7D1), preferentially detected the extracted form of TsF, whereas the secreted TsF was easily detected by the combination of anti-Ct (7D1) and anti-I-Jb. In fact, the assay system defined two types of Ts hybridomas: one producing TsF in cytoplasm or on the membrane but not secreting and another secreting in the culture supernates. We also demonstrated that materials bound to the plate coated with anti-Ct antibody that had been incubated with different concentrations of cell-free extracts exhibited the dose-dependent suppression of antibody responses.     

Immunoregulation of lysozyme-specific suppression. II. Hen egg-white lysozyme-specific monoclonal suppressor T cell factor suppresses the afferent phase of delayed-type hypersensitivity and induces second-order suppressor T cells

Culture supernatant from a monoclonal T cell lymphoma line (LH8-105) obtained by radiation leukemia virus-induced transformation of hen egg-white lysozyme (HEL)-specific suppressor T lymphocytes is able, when injected into mice, to specifically suppress the delayed-type hypersensitivity (DTH) reaction induced by HEL. The suppressor T cell factor (TsF) exhibits fine antigenic specificity since it suppresses the DTH response induced by HEL without affecting the DTH response induced by ring-necked pheasant egg-white lysozyme (REL), a lysozyme closely related to HEL. Conversely, LH8-105 TsF is able to suppress the DTH response induced by human lysozyme, distantly related to HEL but sharing a common epitope critical for induction of suppressive activity. The fine antigenic specificity of LH8-105 TsF for a restricted epitope on the HEL molecule is confirmed by binding to HEL but not to REL immunosorbents. This TsF also bears I-J determinants, as demonstrated by binding to monoclonal anti-I-J immunosorbents, and it suppresses the afferent but not the efferent phase of the DTH response to HEL. The afferent suppression is controlled by genes apparently mapping in the I-J subregion of the H-2 complex since I-J-incompatible mice are not suppressed by LH8-105 TsF injection. This inducer-type TsF induces second-order effector suppressor T cells only in HEL-primed mice indicating the primary role of antigen, in association with H-2 (I-J) products, in the afferent portion of this suppressive circuit.     

Immunosuppressive factor(s) specific for L-glutamic acid50-L-tyosine50. IV. In vitro activity and immunochemical properties.

The responsiveness of BALB/c spleen cells to the terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT), the copolymer of L-glutamic acid50-L-tyrosine50 (GT) and the corresponding complexes with methylated bovine serum albumin (MBSA) has been studied in vitro in a modified Mishell-Dutton culture system. Cultures of BALB/c spleen cells respond to GAT, GAT-MBSA and GT-MBSA over a wide dose range. Contrary to in vivo findings BALB/c spleen cell cultures respond to GT in vitro although in a much narrower dose range. Lymphoid extracts from GT-primed BALB/c or B10.BR mice (GT-TSF) specifically suppress the GT-MBSA response in vitro. This culture system has allowed us to further investigate immunochemical properties of both BALB/c and B10.BR GT-TSF-GT-TSF from both strains display affinity for GT-Sepharose and bear determinants encoded by the I region of the H-2 complex. Moreover, we demonstrate that the suppressive activity from B10.BR mice is a molecule or a molecular complex which displays affinity for GT and bears determinants of the I-J subregion of the H-2k haplotype.     

Murine interstitial nephritis. VIII. Characterization of Igh-V restriction determinants in the development of anti-idiotypic immunity using blocking antibodies

We have prepared antisera specific for Igh-V-linked determinants (alpha Igh-V) in order to study Igh-V restriction during the development of protective, T cell-mediated anti-idiotypic immunity in autoimmune interstitial nephritis. Suppressor T cells in this network use an antigen-binding (RE-Id+) factor (TsF1) secreted by first-order suppressor cells (Ts-1) to induce an anti-idiotypic (RE-alpha Id+) soluble factor (TsF1) released by effector-phase, Ts-2 suppressor cells. Each of these soluble suppressor factors requires homology in the Igh-V region to complete its regulatory functions. Our alpha Igh-V antisera, adsorbed against network idiotypes, can interfere with the Igh-V restriction used in the induction of Ts-2 suppression by TsF1. The antisera bind both TsF1 and TsF2 in an allele-specific manner and are cytotoxic to induced Ts-2 cells, but not their precursors. These Igh-V determinants appear to behave like activation molecules. They lie outside of the ligand-binding site, do not map with the serologic binding of idiotype, and thus act as distinct associative-recognition elements in the maturation of anti-idiotypic immunity.     

General considerations in the interpretation of I-J genetic restrictions: evidence that the antigen-binding chain of antigen-specific T-suppressor factor has two recognition sites for members of the I-J hierarchy

(CBA X B10)F1 [(H-2k X H-2b)] mice produce two types of antigen-specific T-suppressor factor (TsF), which can be separated by affinity chromatography on anti-I-J monoclonal antibody. After reduction and alkylation, both chains of F1 TsF are required for biological activity. However, the antigen-binding chain (AgBC) of F1 TgFk (AgBCk) is only complemented by I-Jk and likewise for F1 TsFb. In other words, interchain complementation shows the same genetic restriction in interchain complementation in parental and F1 mice. F1 TsF bearing, for example, I-Jk (TsFk), interacts with haptenized 'antigen-presenting cells' ('APC') and parental I-Jk chains interacts with haptenized 'APC' of both parental haplotypes (dual reactivity). In contrast, the combination of parental AgBCb and F1 I-Jb shows single reactivity and only interacts with haptenized 'APCb'. It was inferred that the antigen-binding chain is responsible for the dual reactivity and, hence, for the interaction with a member of the I-J hierarchy on the 'APC'. It was concluded that the antigen-binding chain of TsF has two recognition sites for members of the I-J hierarchy--one for interchain complementation and the other for interaction with the haptenized 'antigen-presenting cell'. The term member of the I-J hierarchy is used instead of I-J because it is not clear whether the AgBC interacts with I-J or a receptor for I-J, or indeed a receptor for that receptor.     

The role of I-J in the suppressor T-cell circuit which influences the effector stage of contact sensitivity: antigen together with syngeneic I-J region determinants induces and activates T suppressor cells

One of the T suppressor circuits induced by picrylsulphonic acid includes the T suppressor cell (Ts-eff) which acts at the efferent stage of the contact sensitivity reaction and produces antigen-specific T suppressor factor (TsF). This factor does not act directly but arms a T acceptor cell (Tacc). This Tacc liberates a non-specific inhibitor when it is armed with TsF and then exposed to picrylated cells sharing the I-J genotype of the source of the TsF. This paper investigates the role of I-J region gene products in this T suppressor circuit. Two approaches were used. Syngeneic CBA (H-2k) lymphocytes were separated into I-J+ and I-J- cells by treatment with anti-I-Jk serum followed by panning on anti-immunoglobulin plates. The cells were then picrylated and used as a source of antigen. Alternatively, B10.A congeneic mice syngeneic (5R) or allogeneic (3R) with CBA at the I-J locus were picrylated and used similarly. The main findings were as follows. (i) The intravenous injection of picrylated I-J+ spleen cells but not a similar number of I-J- cells induced Ts-eff which blocked the transfer of contact sensitivity. Picrylated unseparated cells syngeneic, but not allogeneic, at the I-J locus were also effective. (ii) It is known that the lymphocytes of mice injected wit picrylsulphonic acid and then re-exposed to antigen by painting with picryl chloride liberate TsF in vitro. The re-exposure to antigen can be replaced by the intravenous injection of picrylated I-J+ cells or by cells syngeneic at the I-J locus the day before harvesting the spleen cells. (iii) The release of non-specific inhibitor by Tacc armed with TsF requires exposure to picrylated I-J+ cells or cells syngeneic at the I-J locus. The requirement for antigen on a cell bearing syngeneic I-J suggests that antigen together with I-J is an activation signal in this T-cell circuit. The simplest explanation is that the receptor of the pristine Ts and of the mature Ts-eff is similar to T suppressor factor.     

Idiotypic and fine specificity analysis of a (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific suppressor T cell hybridoma at the level of cell surface structures, isolated receptor material and functional suppressor factor

The (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific T suppressor cell hybridoma 7C3-13 was established by fusing splenic B10.BR T cells enriched on NP-coated petri dishes with the AKR thymoma BW5147. 7C3-13 was selected by anti-NPb idiotypic and anti-I-Jk antibodies in microcytotoxicity tests. The hybridoma expressed H-2k, I-Jk, Qa-1, Thy-1.1 as well as idiotypic (binding site-related) and framework Ig VH determinants, while it was negative for I-A, I-E/C, Thy-1.2, Lyt-1, Lyt-2 and Ig constant region determinants. Hapten-binding receptor material could be isolated from 7C3-13 cells on NP-coupled nylon nets and functionally active T suppressor factor (TsF) could be extracted from the hybridoma. Both types of soluble molecules express NPb idiotype, but the TsF carries I-J determinants in addition while the isolated receptors do not. The molecular weight of the isolated receptor material is 80 000, that of the TsF activity is 27 000 and 57 000-64 000, respectively. We thus were able to show that NP-binding molecules can be obtained in the form of cellular surface receptors, isolated receptor material and extracted TsF from one and the same, monoclonal, cell source.     

Genetic Control of the Murine IgM Plaque-Forming Cell Response to Type III Pneumococcal Polysaccharide

The direct 5-day plaque-forming cell response of different inbred mouse strains to pneumococcal polysaccharide type III (SSS-III) varied from more than 10,000 per spleen, in BALB/c mice, to less than 2000 in C57BL mice. Responses of Igh congenic and recombinant inbred lines bearing different combinations of BALB/c and C57BL genes indicate that two or more gene loci are involved in controlling high or low responses. At least one is in the Igh-V region since BALB/c, BAB-14, and CB-8 KN mice (Igh-Va) had two to four times higher responses than CB-20 and CB-16 KN mice (Igh-Vb). Other gene loci must be involved, but nothing can be said about them at present.     

Non-specific inhibitor made by T acceptor cells inhibits both the afferent and efferent stage of the contact sensitivity reaction.

In the T suppressor circuit which affects contact sensitivity, the T acceptor cell (Tacc) armed with T suppressor factor (TsF) and then triggered by antigen and major histocompatibility complex products (I-J) releases non-specific inhibitor (nsINH). These non-specific inhibitor(s) affect both the efferent and afferent stage of the contact sensitivity reaction and were originally detected by the inhibition of the passive transfer of contact sensitivity. The nsINH also blocks the induction of contact sensitivity when given intravenously at the time of immunization but has no effect when given at the time of challenge. Similarly, it blocks proliferation in the regional lymph nodes induced by contact sensitizer in a dose-dependent fashion; it acts when given at the time of immunization but not 1 day later. This effect is antigen non-specific and H-2 unrestricted. The nsINH bears I-J determinants as shown by affinity chromatography on monoclonal antibody. The nsINH comes from the Tacc and is not a breakdown product of the TsF. This is shown by the fact that, when the Tacc and TsF have I-J of different genotypes, the genotype of the nsINH corresponds to that of the Tacc. Parallel measurements of inhibition of lymphoproliferation and of passive transfer show that the nsINH has a molecular weight of 50-60 Kd and a pI around 6.8 and suggest that similar or identical molecules block both the afferent and efferent stage of the contact sensitivity reaction.     

Spleen cell cytokine secretion in Mycobacterium bovis BCG-infected mice.

Three susceptible mouse strains, i.e., BALB/c (H-2d), C57BL/6 (H-2b), and major histocompatibility complex-congenic BALB.B10 (H-2b), were infected intravenously with 4 x 10(6) CFU of live Mycobacterium bovis BCG and analyzed 4 weeks later for in vitro spleen cell cytokine secretion in response to purified protein derivative (PPD), BCG culture filtrate (CF), BCG cellular extract, total BCG, the purified extracellular 30-32-kDa antigen (the fibronectin-binding antigen 85), or the intracellular 65-kDa heat shock protein. C57BL/6 and BALB.B10 mice produced 5- to 10-fold more gamma interferon and interleukin-2 (IL-2) when stimulated with CF, PPD, and antigen 85 than BALB/c mice did. When stimulated with BCG extract and whole BCG, gamma interferon and IL-2 levels were generally lower and comparable in the three strains. IL-4 was detected in spleen cell culture supernatants from infected BALB/c mice but not from C57BL/6 or BALB.B10 mice. IL-5 could not be detected. C57BL/6 and BALB.B10 spleen cells also produced more tumor necrosis factor alpha and IL-6 after stimulation with PPD and CF than BALB/c cells did. Finally, BCG vaccination generated efficient protective immunity in C57BL/6 and BALB.B10 mice but not in BALB/c mice. These data suggest that secreted mycobacterial CF antigens selectively induce a strong TH1 response in BCG-infected C57BL/6 and BALB.B10 mice, whereas in BALB/c mice this response is partly counterbalanced by TH2 cells.     

Cell-mediated immunity in experimental murine dermatophytosis. I. Temporal aspects of T-suppressor activity caused by Trichophyton quinckeanum.

Cutaneous dermatophyte infections caused by Trichophyton quinckeanum were established in various strains of mice. All congenic BALB/B (H-2b), BALB/c (H-2d) and BALB/K (H-2k) strains showed high susceptibility to dermatophyte infection. Susceptibility is independent of MHC phenotype, since other strains with corresponding H-2 haplotypes such as C57BL/6 (H-2b), DBA/2 (H-2d) and CBA (H-2k) were resistant to the disease. During the acute phase of infection in BALB/c mice, the in vitro blastogenic responses of regional lymph node cells was suppressed. Suppression was observed for both the T cell mitogens concanavalin A and phytohaemagglutinin, and for the B cell mitogen lipopolysaccharide. A series of cell-mixing experiments revealed that lymph node cells from infected mice were able to suppress the T cell and B cell mitogenic responses of lymph node cells from normal mice. Suppression was mediated by T cells and abrogated by treatment of lymph node cells with either monoclonal anti-thy-1.2 or anti-Ly-2.2 and complement. In this report, we discuss the possibility that T-suppressor mechanism mediated by cells bearing the Ly-2+ phenotype and activated during dermatophyte infection may determine the course of the disease.     

Immunological activity of a T-hybrid line. II. Mapping H-2 genes for the SRBC-specific suppressor factor, its acceptor, and suppression of the antibody response

Studies are reported on the nature and action of a suppressor factor with specificity for sheep red cells produced by a mouse T-hybrid cell line. Absorption of the factor with anti-H-2 reagents indicated that it carries determinants coded between the I-J and D loci. The factor was bound well by spleen cells of certain strains (B10, B10.BR), but not others (B10.S); absorption studies with spleen cells of H-2 recombinant strains suggested that a gene contributing to a cellular acceptor site for the factor also mapped in the region between I-J and D. On the other hand, studies of functional suppression of the anti-SRBC response of different strains in vitro indicated that an H-2 gene in the I-A or I-B subregions controlled suppression. Thus, at least two H-2 genes seem to be involved in the suppressive action of this factor.     

Anti-Inulin [β-(2→1)-Linked Polyfructose] and Anti-Grass Levan [β-(2→6)-Linked Polyfructose] Antibody Response in Mice

Anti-inulin [β-(2 → 1) polyfructosan Brucella abortus (InuBA)] and anti-grass levan [β-(2 → 6) polyfructosan] antibody responses in BALB/c and C57BL mice and in their F₁ and backcross progeny, as well as in immunoglobulin congenic and Bailey recombinant inbred strains derived from BALB/c and C57BL mice, were examined. The anti-inulin antibodies could accommodate both β-(2 → 1)- and β-(2 → 6)-linked polyfructosans, and 97% of the anti-inulin plaque-forming cells (PFC) from BALB/c mice expressed the cross-reactive idiotypes (InuIdX) shared by the BALB/c inulin- and levan-binding myeloma proteins. Of the C57BL mice, only 25% produced high anti-inulin response, and none exhibited the InuIdX of BALB/c anti-inulin antibodies. The percentages of InuIdX⁺ anti-inulin PFC were also examined in other strains with high anti-inulin response. In C58 and AL mice, 80% of anti-inulin PFC were InuIdX⁺, whereas in A/He and RIII mice, only 40% were InuIdX⁺. All strains examined developed high anti-grass levan response, and the antibodies were specific for β-(2 → 6) structures and did not exhibit InuIdX. Comparison of the magnitude of the anti-inulin antibody titers in response to InuBA in BALB/c, C57BL, and their F₁ and backcross progeny, as well as in immunoglobulin congenic (i.e., B.C-8, BAB-14, and C.B-20) and recombinant inbred strains derived from BALB/c and C57BL mice, showed that all mice having the IgCH^a(BALB/c) allotype gave high anti-inulin response. In addition to the InuIdX structural genes, the effects of allotype-linked or unlinked “regulatory” genes were also indicated by the lower anti-inulin response in B.C-8 and BAB-14 mice compared with BALB/c mice and the higher anti-inulin response in C.B-20 mice compared with C57BL mice. A multigene interaction in controlling the production of the anti-inulin antibodies was implicated.     

H-2 linkage control of resistance to subcutaneous infection with Mycobacterium lepraemurium.

The H-2 linkage of the gene or genes controlling resistance to subcutaneous infection with 10(7) Mycobacterium lepraemurium organisms was investigated by using H-2 congenic strains on BALB and B10 backgrounds. Resistance was assessed by counting the organisms present at the infection site in the footpad and in the draining (right popliteal) lymph node 20 weeks after infection. When mice of BALB and B10 backgrounds with the same H-2 haplotype were compared, the BALB mice were always more susceptible. However, BALB/K (H-2k) mice were more susceptible than BALB/B (H-2b) mice, and BALB/B mice were more susceptible than BALB/c (H-2d) mice. There was no detectable difference in the resistance of B10.D2/n (H-2d) mice and B10 (H-2b) mice, but B10.BR (H-2k) mice were more susceptible than mice of the other two B10 strains. BALB/K was the only strain in which a high proportion of mice showed significant dissemination of organisms to the liver and spleen.     

Growth and metastasis in allogeneic hosts. Lack of H-2-negative or somatic hybrid variant selection

In vitro cultured B16 melanoma cells, which were previously found to have an impaired expression of H-2Kb and Db (as evaluated by antisera absorption assay), were used to study growth and metastasis in allogeneic mice in relation to H-2 expression. The possible emergence of somatic hybrids with host cells was also examined. B16-A cells grown subcutaneously in allogeneic BALB/c mice (H-2d) did not show a lack of H-2b expression, nor the acquirement of H-2d antigens was found. Spontaneous lung metastases were found in about 30% of BALB/c mice with progressing B16 tumor. Single lung metastases showed higher H-2b levels than cells from the respective tumors, and did not express host H-2 antigens. Tumor take was concomitant to the rise of an anti-H-2b humoral response: disease outcome was independent from the serum titer. B16-A cells injected intravenously in BALB/c mice gave rise to lung colonies; different colonies showed a wide range of H-2b antigens levels and no H-2d expression. Lung colonization capacity in normal allogeneic BALB/c mice was significantly higher than in syngeneic C57BL/6 mice. Both syngeneic and allogeneic mice, when pretreated with cyclophosphamide (CY) to reduce natural killer cell activity, showed a significant increase in lung colonization by B16-A cells. CY-treated C57BL/6 mice showed significantly higher numbers of lung colonies than CY-treated BALB/c mice. In conclusion, B16 growth and metastasis in the allogeneic environment do not seem to be determined by a selection of H-2-negative variants or by the emergence of somatic hybrids with host cells.     

Major histocompatibility complex control of the idiotypic network in the MOPC 173 system

Regulation of the anti-idiotypic response against MOPC 173 (M-173, γ_2a, ? myeloma of the BALB/c strain) was studied after syngeneic and allogeneic immunizations. The immunogen was M-173 polymerized with glutaraldehyde, and hemagglutinating titers (HT) were determined with sheep red blood cell-M-173. H-2 regulation of the response was clearly shown in mice having the same Igh-C^a genes as the immunogen protein. H-2^d mice (BALB/c) are dispersed responders (HT: 80-81 920) and 30% did not respond. H-2^k mice (BALB.K) are high responders (HT: 10240-81920), and H-2^b mice (BALB.B) are nonresponders (HT < 40). In animals of a non-BALB background, similar observations were made: Igh-C^a, H-2^k mice (C58) were responders, whereas Igh-C^a, H-2^b mice (C57L) did not respond. However, more dispersed HT values for the C58 animals as compared with those of the BALB.K suggest that a second level of regulation by background genes might be superimposed. When alloimmunization was used in strains not expressing the Igh-C^a allotype (b, e, j), animals responded whatever the H-2 haplotype (b, k, d). In this case, allotypic determinants might play a carrier role. All responder mice consistently made antiidiotypic antibodies as determined by hemagglutination and/or radioimmunoassay. Antibodies against new glutaraldehyde-induced determinants were also produced but appeared in low amounts in syngeneic immunizations. In allogenic immunizations, various levels of anti-allotype antibodies were detected. BALB.B (and BALB/c) mice are responders to U-10 (γ_2a,?, BALB/c myeloma), polymerized with glutaraldehyde and can respond to the M-173 idiotype when they are immunized with M-173 coupled to a heterologous carrier (a human γ₁, ? myeloma protein, Kle). The unresponsiveness of BALB.B mice to M-173 is thus idiotype-specific and is not due to a defect in the anti-idiotypic antibody repertoire. Injection of M-173 before M-173-Kle prevents the response to M-173 but not to Kle, which favors the occurrence of suppressive T cells. Responsiveness is dominantly transmitted in (BALB.B × BALB.K)F₁ mice which are Igh-C^a/a, H-2^b/k heterozygotes. Unresponsiveness found with the Igh-C^a, H-2^b combination is also observed in (BALB.B × B10)F¹ which are Igh-C^a/b, H-2^b/b. Since F₁ animals between BALB.B and B10.A (3R), (4R) or (5R) are all nonresponders, genes involved in the response to M-173 are not in the K, I-A, I-J, or I-E subregions. A participation of the I-B subregion or an I-A + I-E/C complementation cannot be excluded.     

Definition of alien H-2 determinants on a Friend leukaemia by analysis of alloreactivity of CTL from primary MLC

A Friend virus-induced tumour of BALB/c (H-2d) origin, HFL/d, was examined for the expression of alien H-2 antigens. The alloantigens on HFL/d were typed by generating CTL in primary MLC with HFL/d as stimulator and measuring reactivity to targets with known H-2 antigens, and confirmed by assessing recognition of HFL/d targets by CTL generated in primary MLC with stimulators expressing known H-2 antigens. Potential cross-reactivities between alloantigens were analysed by cold-target inhibition experiments. BALB/c cells stimulated with HFL/d lysed H-2b targets, and BALB/c anti-H-2b CTL lysed HFL/d; analysis with recombinant haplotypes demonstrated both H-2Kb and H-2Db alien antigens antigens on HFL/d. C57BL/6 (H-2b) cells stimulated with HFL/D recognized H-2Kd, H-2Dd, and an additional determinant unique to HFL/d. (BALB/c x B6)F1 cells also recognised a unique HFL/d determinant not of H-2b or H-2d origin. These unique determinants, which induced a strong cytotoxic response in primary MLC, were not shared by BALB/c or B6 tumours induced by cross-reactive FMR viruses. Thus, HFL/d expressed the K and D antigens of its strain of origin, two typed alien H-2 antigens, and at lest one other untyped antigen which may represent an additional H-2 determinant. These studies further demonstrate the utility of examining the reactivity of CTL generated in primary MLC to probe for the presence of alien H-2 antigens.     

Rejection of bone marrow cell allografts by natural killer cell subsets: 5E6+ cell specificity for Hh-1 determinant 2 shared by H-2d and H-2f.

The 5E6 antigen, defined by anti-5E6 mAb, is expressed on one-half of murine natural killer (NK) cells, and we have previously demonstrated (C. L. Sentman et al., J. Exp. Med. 1989. 170: 1991) that 5E6+ NK cells are necessary for the rejection of BALB/c (Hh-1d) but not C567BL/6 (Hh-1b) bone marrow cells (BMC). In experiments described here, we have characterized the specificity of 5E6+ and 5E6- NK cell subsets for hemopoietic histocompatibility-1 (Hh-1) antigens. Prospective recipient mice were treated with anti-5E6 mAb and challenged with BMC from a variety of donors. In addition, H-2d/Hh-1d C.B-17 scid 5E6+ or 5E6- NK cells were adoptively transferred into irradiated, NK cell-depleted hosts and challenged with H-2b/Hh-1b BMC. The data indicate that the 5E6+ NK cells are necessary for the rejection of only those BMC that express the Hh-1 determinant 2 shared by H-2d and H-2f haplotypes of strains BALB/c (d), A.Ca (f), and B10.M (f). No reactivity to other Hh-1 antigens resides in the 5E6+ population. In contrast, the ability of NK cells to lyse H-2d or H-2b tumor cells was independent of 5E6 expression. These results suggest that the 5E6 molecule is likely to be important in the specific recognition and rejection of BMC that express Hh-1 determinant 2, and is probably not involved in recognition of "tumor target cell structures".     

Effect of genetic variation on induced neutrophilia in mice.

Mice from a variety of strains were injected with a sterile irritant (Brewer's thioglycolate) and killed bacteria (Staphylococcus aureus, Staphylococcus epidermidis, or Escherichia coli) to determine their effect on accumulation of neutrophils in the peritoneal cavity. Peak accumulation occurred around 15 h postinjection and showed significant strain-related variation. C57BL/10 mice were identified as having a high-responder phenotype and BALB/c mice a low-responder phenotype. Inheritance of the high-responder phenotype followed simple Mendelian genetics: (BALB/c x C57BL/10)F1 mice were found to be more responsive than either parental phenotype. Major histocompatibility complex H-2d haplotype was found to convey an augmented neutrophil response in conjunction with B10 background high-responder genes (B10.D2/n) but the H-2d haplotype per se was not the only factor in determining high responsiveness. Gram-positive and gram-negative bacteria appeared to activate different immune mechanisms. Both gram-negative bacteria and lipopolysaccharides (LPS) induced a response similar to, but less potent than, that induced by Brewer's thioglycollate. Neutralization of the LPS content of Brewer's thioglycolate abrogated the response.     

Stimulation of specific suppressor T cells in newborn responder mice by the terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT).

The effects of immunization with the terpolymer of L-glutamic acid60-L-alanine40-L-tyrosine10 (GAT), the copolymers of L-glutamic acid60-L-alanine40 (GA) and of L-glutamic acid50-L-tyrosine50 (GT), were compared in adult and newborn BALB/c and BALB.B mice. as expected, BALB/c (H-2d) and BALB.B (H-2b) adult mice were responders to GAT and GA and nonresponders to GT, which induced suppressor T cells in BALB/c but not in BALB.B mice. in contrast, newborn mice expressed different phenotypes. Two-week-old mice developed responses to GAT, GA and GT-complexed methylated bovine serum albumin, but immunization at birth with these copolymers induced a cross-reactive tolerance in both strains. Neonatal GAT tolerance could be transferred in adult and involved suppressor T cells in the two inbred strains, whereas the GT-specific immune suppression was not demonstrable in newborn BALB/c mice. The significance of these data to our understanding of the regulation of specific immune response and tolerance is discussed.