Genetic differences in BCG-induced resistance to Schistosoma mansoni are not controlled by genes within the major histocompatibility complex of the mouse.

Induction of nonspecific resistance to Schistosoma mansoni infection after the i.v. injection of viable BCG was investigated in outbred mice and a panel of inbred and H-2 congenic strains. Significant protection was induced in CF1, A/J, C57BL/6, C57BL/10, DBA/2, C57BR, and SJL mice. BALB/c mice were not protected whereas CBA and C3H mice expressed intermediate degrees of protection. Expression of the protective phenomenon is not controlled by genes within the MHC as shown by the marked differences in response between BALB/c and DBA/2 (H-2d) as well as between C57BR and C3H (H-2k) mice. H-2 congenic strains with C57BL/10 background (B10.A and B10.D2) were high responders. BALB.B10 mice carrying the high responder (B10) MHC on the nonresponder (BALB/c) background were not protected. The degree of splenic hypertrophy did not correlate with the expression of nonspecific resistance. These results demonstrate that, in addition to controlling specific immune responses, genetic differences influence the nonspecific protective phenomena related to BCG administration as well.     

Specificity of the mouse cytotoxic T lymphocyte response to adenovirus 5. E1A is immunodominant in H-2b, but not in H-2d or H-2k mice

The Ag specificity and MHC restriction of the CTL response to adenovirus 5 (Ad5) in three strains of mice, C57BL/10 (H-2b), BALB/c (H-2d), and C3H/HeJ (H-2k), were tested. Polyclonal Ad5-specific CTL were prepared by priming mice in vivo with live Ad5 virus followed by secondary in vitro stimulation of the spleen cells with virus-infected syngeneic cells. The Ad5-specific CTL were Db restricted in C57BL/10 and Kk restricted in C3H/HeJ. In BALB/c mice both Kd- and Dd/Ld-restricted CTL were detected. The polyclonal Ad5-specific CTL response in C57BL/10 mice is directed exclusively against the products of the E1A region, which comprises only 5% of the Ad5 genome. In BALB/c mice E1A is at best a very minor target Ag and in C3H/HeJ mice E1A is not recognized at all. Using the H-2 congenic mouse strains B10.BR (H-2k) and C3H.SW (H-2b) it was shown that the immunodominance of E1A is H-2 dependent. The 19-kDa glycoprotein encoded in the E3 region of Ad5, which binds to class I MHC in the endoplasmic reticulum and prevents its translocation to the cell surface, does not affect the specificity of the CTL response in C57BL/10 mice toward E1A. However, it affects the MHC restriction of the Ad5-specific response in BALB/c mice, selectively inhibiting generation of Kd-restricted CTL.     

Degree of proliferative response to concanavalin A of spleen cells of mice of different strains and production of interleukin-2

Differences in the lymphoproliferative response to Con A of spleen cells allowed one to distinguish a high responder (BALB/c and DBA/2) and low responder (C57BL/6 and CC57BR) mice. BALB/c and DBA/2 mice (H-2d haplotype) produced interleukin 2 better, than C57BL/6 and CC57BR mice (H-2b haplotype). However acceptance of interleukin 2 was better in BALB/c and C57BL/6, than in DBA/2 and CC57BR mice. Summarizing these facts the authors suppose that the differences in interleukin 2 production and acceptance play an important role in the height of lymphoproliferative response.     

Suppression of antibody responses in allogeneic mice by products of lymphoid tissue. II. Lack of antigenic specificity and immunogenetic requirements of allogeneic suppressive factor (ASF).

Mice were irradiated, infused with thymocytes and immunized with a variety of antigens, i.e., sheep or horse red blood cells (SRBC or HRBC), diphtheria toxoid (DT) or bovine gamma-globulin (BGG). The spleen cells (T.Spleen cells) were harvested 5 days later and cellfree extracts were prepared. The extracts contained an allogeneic suppressive factor (ASF) that was capable of inhibiting IgM antibody responses of allogeneic or semi-allogeneic unirradiated mice. ASF had to be injected within 24 hr of immunization to be effective and a single injection delayed, rather than abolished, the antibody response at the cellular level. However, daily injections of ASF resulted in persistent suppression of antibody response. ASF activity was antigen nonspecific, i.e., the antigen used to stimulate ASF production did not have to be the same as the antigen used to test for ASF activity. C3H T.Spleen extracts were even immunosuppressive when prepared by exposure to C3BF1 alloantigens only; such extracts suppressed antibody responses of C3BF1 and DBA/2 mice. C3H ASF was removed from extracts after incubation with C3BF1 spleen cells but not after incubation with C3H spleen cells. C3BF1 spleen cells which had been preincubated with C3H ASF were unable to generate antibody-forming cells upon transfer to irradiated C3BF1 host mice. This suggests that the ASF molecule may be or include receptors for alloantigens. The immunogenetic requirements for ASF activity were evaluated by injecting extracts from C3H, C57BL, C3BF and BALB/c T.Spleen cells into C3H, CBA, C57BL, BALB/c, DBA/2, A or C3H.A recipient mice. All extracts tested had ASF activity. However, all allogeneic recipients were not suppressed by the extract material. The suppressive activity of ASF seemed to require two (or more) antigenic differences between donors and recipients of extract material, an H-2K or I antigen difference and a second antigen difference, possibility Ig-1. In the limited numbers of strain combinations tested, T.Spleen extracts suppressed IgM antibody response only if exposed to H-2 and Ig-1 antigens, e.g., BALB/c (H-2d, Ig-1a) ASF suppressed A (H-2a, Ig-1e) but not C3H.A (H-2a, Ig-1a) or DBA/2 (H-2d, Ig-1c). Separate ASF molecules may react with separate antigens on the cell surface, i.e., with H-2 and gammaG2a. Alternatively, one ASF molecule may react with two structurally associated antigens. If the latter is correct, it is conceivable that the beta2-microglobulin which is non-covalently linked to the major component of H-2 molecules expresses allotypic antigens coded for by Ig-1 and beta2-microglobulin is one of the antigens recognized by ASF.     

Hybrid resistance to BALB/c plasmacytomas. I. Resistance to MPC-11 controlled by a locus not linked to H-2.

Genetic control of hybrid resistance to the BALB/c plasmacytoma MPC-11 was investigated. The results indicate that a single dominant autosomal gene or gene complex, which segregates independently of H-2 and the coat color c and b-loci, controls resistance to this tumor. This gene has the same strain distribution pattern in the CXB Bailey recombinant inbred strains as three unlinked genes, H-2, Ly-4, and Ea-4. It is possible, therefore, that it could be linked to either of the latter two loci. Strains that carry a positive allele for resistance are C57BL/10 and all of its congenic resistant partners tested, C57BL/6, C57L, C57BL/Ks, AKR, and DBA/1. BALB/c and its congenic resistant partners are presumed to carry a negative allele of the gene for resistance to MPC-11. Strains such as SJL, DBA/2, and A and its congenic resistant partners, which form susceptible hybrids with BALB/c, could carry either the negative allele of the gene for resistance, like BALB/c, or could carry both a positive allele of the gene and some other gene conferring susceptibility on the hybrids. Heterozygosity within the H-2 complex increases resistance only in the presence of this non-H-2 linked gene for resistance, and the effect maps to the left of the H-2D region.     

Macrophage-mediated suppression of immune responses in Toxoplasma-infected mice. II. Both H-2-linked and -nonlinked control of induction of suppressor macrophages

The suppressive effect of Toxoplasma infection on initiation of memory cells to dinitrophenylated keyhole limpet hemocyanin (DNP-KLH) was drastically different among inbred strains of mice. C57BL/6 (B6), C57BL/10 (B10), and SJL mice showed markedly suppressed secondary anti-DNP responses when infected. In contrast, the suppression did not occur in BALB/c mice. The infected DBA/2 and C3H/He mice produced moderately suppressed responses. In B6 mice, an injection with 1 X 10(2) organisms of T. gondii induced a suppressed elicitation of the memory cells to DNP-KLH. However, in BALB/c mice, the responses were not affected even by inoculation with 1 X 10(4) organisms. The difference in the suppressive effect of infection between B6 and BALB/c mice was also observed in the primary anti-DNP antibody responses to DNP-KLH. Both H-2-linked and -nonlinked genes appeared to be responsible for the regulation of the immunosuppression, since the suppressive effect of infection in B10.D2 mice, which have the B10 background and the same H-2 haplotype as BALB/c, was weaker than that of B10 mice, but stronger than in BALB/c mice. In vitro studies using a primary anti-sheep erythrocytes (SRBC) antibody response system demonstrated that the activation of plastic-adherent suppressor cells by Toxoplasma infection, in which suppressor macrophages have been proved to be the responsible cells for the suppressive activity, was controlled by both H-2-linked and -nonlinked genes.     

Genetic control of heat sensitivity and activity level of murine arylsulfatase B

BALB/c male mice possess twofold higher kidney p-nitrocatechol-SO4 arylsulfatase B than do A/HeJ male mice; however, their liver arylsulfatase activities are comparable. Twentyfold-purified kidney arylsulfatases B from these two strains have similar Michaelis constants, electrophoretic mobilities, pH optima, and inhibitor profiles; however, the BALB/c enzyme is more heat stable than the A/HeJ enzyme. BALB/c, C3H/HeJ, DBA/2J, and SWR/J mice share an autosomal allele, As-1a, which apparently determines the heat-stable arylsulfatase B, while A/HeJ and C57BL/6J mice possess the As-1b allele, which determines the heat-sensitive enzyme. A second autosomal locus, Asr-1, determines liver arylsulfatase B activity. C57BL/6J mice carry the Asr-1a allele, which results in high liver activities, while C3H/HeJ mice are homozygous for the low-activity allele, Asr-1b. Male mice generally have 30-40% higher kidney activities than females; however, female kidney arylsulfatase activities rise and actually surpass those of males during late pregnancy and lactation.     

Genetic control of interleukin-2 production in inbred mice

BALB/c mice (H-2d haplotype) produced IL 2 better than C57BL/6 mice (H-2d haplotype). However genetic analysis in F2 generation demonstrated independent segregation of the IL 2 production intensity and H-2 haplotype. Investigation of the IL 2 production intensity in BALB/c, C57BL/6 and their F1 and F2 generation revealed that this was controlled by only one gene.     

A new erythrocytic antigen of C57BL/10 (B10) mice

A new antigen, detectable on murine erythrocytes by hemagglutination assay with a (BALB/cCrl X SWR/J)F1 anti-B10.D2n/Sn alloantiserum, is described. Among the inbred and congenic mouse strains tested for reactivity with the antiserum, only the immunizing strain, B10.D2, and its congenic resistant partner, C57BL/10 (B10), reacted. Three other C57 strains, C57BL/6J, C57BL/6By, and C57L, were negative for the antigen. F1 hybrids between B10 and BALB/c, an antigen-negative strain, were positive for the antigen indicating that its expression is dominant. Typing of 39 (BALB/c X (BALB/c X B10)F1) and 62 [BALB/c X B10)F1 X BALB/c) backcross mice revealed that a single gene controls expression of the antigen. The gene is autosomal and not linked to H-2, Ly-4, or the c (albino) or b coat color genes.     

Genetic control of immune responses to the 18-kDa protein of Mycobacterium leprae. Different TH1 subsets may be involved in proliferative and delayed-type hypersensitivity responses.

In vitro and in vivo responses to the 18-kDa protein of Mycobacterium leprae have been analysed in different strains of mice. Lymphocytes from BALB/cJ (H-2d), BALB.B (H-2b), B10.BR (H-2k), and B10.M (H-2f) mice primed with 18-kDa protein yielded high T cell proliferative responses, while those from C57BL/10J (H-2b) mice yielded lower responses. Both H-2 and non-H-2 genes contributed to the magnitude of responsiveness. F1 mice from high and low responder strains showed high responsiveness to the 18-kDa protein. Supernatants from lymph node cell cultures prepared from 18-kDa protein-immunised BALB/cJ, B10.BR, and C57BL/10J mice contained IL-2 but no IL-4, indicating that activated T cells from both high and low responder mice were of a TH1 phenotype. Cell cultures from low responder C57BL/10J mice produced less IL-2 than those from high responders. The low responsiveness to the 18-kDa protein in proliferative assays might be due to a low frequency of antigen-specific T cells in the C57BL/10J mouse strain. BALB/cJ, C57BL/10J, and F1 (BALB/cJ x B10.BR) mouse strains were tested for in vivo DTH reactions to the 18-kDa protein. All strains, including C57BL/10J, were high DTH responders. Although DTH effector cells and 18-kDa protein-specific proliferative T cells belong to the TH1 subset, our data comparing high and low responder status indicate that distinct TH1 subpopulations are stimulated in response to the 18-kDa protein of M. leprae.     

Analysis of cytotoxic mechanisms induced by minor histocompatibility antigens in the mouse.

Following immunization of BALB/c (H-2^d) mice against the P815Y (H-2^d) mastocytoma, two populations of effector cells could be identified in the spleen, namely, the cytolytic T cell and a cytostatic effector, which was resistant to anti-T-cell serum and complement and appeared to be adherent. Quantitative comparison of the activities of both effectors has been made with the levels of activity obtained following immunization across the major H-2 barrier in C57BL10 (H-2^b) mice. While T-cell activity was significantly lower in BALB/c mice, the non-T-cytostatic activity was greater compared with C57BL mice. Therefore, H-2 antigens do not appear to be essential for the efficient induction of the cytostatic effector.     

Myelin proteolipid protein-induced experimental allergic encephalomyelitis. Variations of disease expression in different strains of mice

Strains of mice with diverse genetic backgrounds were tested for susceptibility to experimental allergic encephalomyelitis (EAE) induced by myelin proteolipid protein. EAE was elicited in all strains of mice tested, but the clinical and histologic features varied. SJL (H-2s) mice had a high incidence of both clinical and histologic disease characterized by early onset of clinical signs. Inguinal lymph node T cells from diseased animals responded specifically [( 3H]thymidine incorporation) to proteolipid protein and not to myelin basic protein. In contrast, BALB/c (H-2d), DBA/1 (H-2q), C57BL/6 (H-2b), AKR (H-2k), CBA (H-2k), C3H (H-2k), B10.BR (H-2k), and C57BR (H-2k) mice showed a later onset of clinical signs and typically a lower disease incidence. However, the most marked variations in disease incidence occurred among BALB/c (H-2d) substrains in which the incidence of EAE ranged from eight of nine (BALB/cPt) to complete resistance (BALB/cWt and BALB/cORNL). Because these BALB/c substrains were initially derived from the same inbred genetic source and are serologically identical at H-2, these results suggest that expression of proteolipid protein-induced EAE in the mouse involves additional loci outside the MHC.     

Dominantly inherited expression of BID, an invariant undiversified T cell receptor delta chain

In BALB/c lung and lymph node gamma delta T cells, a large fraction of the expressed V delta 5 genes consist of an invariant sequence, BID (for BALB/c invariant delta). BID results from a direct joining of the V delta 5, D delta 2, and J delta 1 segments, which conserve their complete germline coding sequences. In C57BL/6 (H-2b) mice, where identical and functional segments are present in the germline, BID is absent. It appears that BID+ gamma delta T cells are positively selected by factors encoded outside of the classical MHC region, as indicated by their dominance in F1(C57BL/6 x BALB/c) and in BALB.B (H-2b) mice. Additional observations, including the expression of BID in BALB/c nu/nu but not in C57BL/6 nu/nu mice, suggest that the expansion of BID+ T cells essentially occurs extrathymically.     

H-2-dependent binding of xenogeneic beta 2-microglobulin from culture media

Sera of C57BL/6 mice contained lymphocytotoxic antibodies after injections with syngeneic lymphoblasts. The antibodies were directed against bovine beta 2-microglobulin, a component of the culture medium, and mimicked H-2-specific antibodies by a preferential recognition of target cells expressing certain H-2 Ag. This "polymorphic" reactivity pattern was due to a variable capacity of H-2 molecules associated with bovine beta 2-microglobulin.     

Murine responses to (Tyr-Glu-Ala-Gly)n: II. H-2 and non-H-2 gene effects

Mice of the H-2^b haplotype responded to the sequential polymer poly(Tyr-Glu-Ala-Gly) in the in vitro T-cell proliferative assay, irrespective of whether they were homozygous or heterozygous at the H-2^b locus. The antibody responses of the H-2^b congenic mice to this polymer were variable, with A.BY and BALB.B showing responses better than those of C57BL/6 and C57BL/10 strains. The antibody responses of the F₁ progeny of (responder × nonresponder) strains of mice to this polymer are generally lower than the responder parents. F₁ mice with C57BL/10 background were the poorest responders. Studies with F₂ mice and backcross progenies of selective breeding of high and low antibody responder (C57BL/6 × BALB/c) F₁ to high responder C57BL/6 mice indicated that both non-H-2 genes and H-2 gene dosage effects influenced the magnitude of the humoral antibody responses. Animals having low responder non-H-2 background and only half the dosage of the responder immune response genes has greatly diminished antibody responses.     

Teratocarcinoma transplantation rejection loci: AnH-2-linked tumor rejection locus

Embryoid bodies (ascites tumor) from a 129/Sv transplantable teratocarcinoma produce tumors (100%) in syngenic 129/Sv mice but fail to form tumors (3–6%) in BALB/c mice, C3H/He mice and C57BL/6 mice, in spite of the fact that the malignant stem cells of this tumor do not express detectable H-2 antigens. The available evidence indicates that this allogeneic tumor restriction has an immunological basis; 100% of the F₁ hybrid mice between 129/Sv and the three other inbred mouse strains accept the 129/Sv teratocarcinoma. The backcross and F₂ mice segregate the BALB/c, C3H/He and C57BL/6 tumor transplantation rejection loci in a manner that indicates that each of these inbred strains of mice contain one to two major transplantation rejection loci. A linkage analysis in the BALB/c and C3H/He backcross and F₂ generations indicates that these mice have a teratocarcinoma transplantation rejection locus on chromosome 17, about eight to nine recombination units from theH- 2 complex. An F₁ complementation analysis between allogeneic mice that each reject teratocarcinomas tumors (BALB/c × C57BL/6 and C3H/He × C57BL/6), indicates that the C57BL/6 mice have the 129/Sv tumor-accepting (sensitive) allele at theH-2-linked locus but reject teratocarcinomas because of antigenic differences at a second locus.While these major teratocarcinoma transplantation rejection loci determine the acceptance or rejection of a tumor by a mouse injected with high doses of tumor tissue (750 g of tumor protein), evidence is presented for a number of minor genetic factors that can (1) affect the efficiency of tumor rejection and (2) cause complete tumor rejection at lower tumor doses (7.5–75 g of tumor protein).     

Genetically determined resistance to lethal murine cytomegalovirus infection is mediated by interferon-dependent and -independent restriction of virus replication.

Susceptibility of 4-week-old mice of different strains to lethal murine cytomegalovirus (MCMV) infection was studied. Strains homozygous for H-2k and C57BL strains were resistant to greater than or equal to 10(5.5) PFU. B10.BR mice congenic for C57BL background genes and H-2k were about 10-fold more resistant than either C3H/HeN or C57BL strains. BALB/c mice (H-2d) were susceptible (50% lethal dose, 10(5.05) PFU). This susceptibility was dominant over resistance associated with H-2k but not that associated with C57BL background genes. The dominant susceptibility trait segregated in backcross mice as if carried by a single gene. Virus replication in spleen cells in vivo correlated with susceptibility to lethal infection. A similar trend was found in tests of salivary glands. Replication of MCMV in vitro in cultures of adherent spleen cells and primary mouse embryo cells correlated with replication in vivo. Neutralization of interferon (IFN) in cultures of adherent spleen cells reversed H-2k-linked restriction of viral replication but had minor effects on cells of other strains. Natural killer cell responses to infection were often higher in more resistant strains, but B10.BR mice developed minimal natural killer cell responses. Specific antibody and cytotoxic T cell responses in B10.BR mice were similar or lower than in other strains. Thus, resistance to lethal MCMV infection was not immunologically mediated, was dependent on and reflected by the capacity of cells from a given mouse strain to support replication in vivo and in vitro, and was IFN dependent and recessive if linked to H-2k but IFN independent when associated with C57BL background genes.     

Major histocompatibility complex-dependent cytotoxic T lymphocyte repertoire and functional avidity contribute to strain-specific disease susceptibility after murine respiratory syncytial virus infection

Susceptibility to respiratory syncytial virus (RSV) infection in mice is genetically determined. While RSV causes little pathology in C57BL/6 mice, pulmonary inflammation and weight loss occur in BALB/c mice. Using major histocompatibility complex (MHC)-congenic mice, we observed that the H-2(d) allele can partially transfer disease susceptibility to C57BL/6 mice. This was not explained by altered viral elimination or differences in the magnitude of the overall virus-specific cytotoxic T lymphocyte (CTL) response. However, H-2(d) mice showed a more focused response, with 70% of virus-specific CTL representing Vβ8.2(+) CTL directed against the immunodominant epitope M2-1 82, while in H-2(b) mice only 20% of antiviral CTL were Vβ9(+) CTL specific for the immunodominant epitope M187. The immunodominant H-2(d)-restricted CTL lysed target cells less efficiently than the immunodominant H-2(b) CTL, probably contributing to prolonged CTL stimulation and cytokine-mediated immunopathology. Accordingly, reduction of dominance of the M2-1 82-specific CTL population by introduction of an M187 response in the F1 generation of a C57BL/6N × C57BL/6-H-2(d) mating (C57BL/6-H-2(dxb) mice) attenuated disease. Moreover, disease in H-2(d) mice was less pronounced after infection with an RSV mutant failing to activate M2-1 82-specific CTL or after depletion of Vβ8.2(+) cells. These data illustrate how the MHC-determined diversity and functional avidity of CTL responses contribute to disease susceptibility after viral infection.     

Function of CD8+ T lymphocytes in a self-curing mouse model of visceral leishmaniasis

CD8+ T lymphocytes play an important role in the control of visceral leishmaniasis in non self-cure mice (e.g. BALB/c). In the present study, the mode of action of CD8+ T cells and their in vivo contribution to immunity was addressed in self-curing C57BL/6 mice. During the course of the experimental infection, CD8+ T cells specific for Leishmania infantum (L. infantum) developed and apoptotic cell death subsequently followed. They exhibited perforin-dependent cytotoxicity and a T(C)1 profile characterized by secretion of IFN-gamma and CC chemokines. Despite evidence for activation of CD8+ T lymphocytes, both intravenous and intradermal infection of beta2-microglobulin deficient C57BL/6 mice with L. infantum showed that these knockout animals had similar parasite loads to their wild-type counterpart. Lymphocytes from the beta2-microglobulin deficient mice produced high levels of IFN-gamma, reflecting a T(H)1 response to the parasite, which was apparently sufficient for the immunologic control of the pathogen. Thus, despite their functional activation, CD8+ T lymphocytes do not appear to play a primary role in parasite restraint in the self-curing mouse model of visceral leishmaniasis, as shown using beta2-microglobulin deficient mice which do not produce functional CD8+ T lymphocytes.