Resistance against tolerance induction in SJL mice

Genetic influences upon eosinophilia and resistance in mice infected with Mesocestoides corti

The genetic influences upon host variation in eosinophilia and resistance to helminth infection, and the relationship between these parameters, was investigated in 9 inbred and 3 hybrid strains of mice infected with Mesocestoides corti. Blood, bone marrow, spleen and peritoneal fluid eosinophilia were far higher in SJL mice than in any other inbred strain. SWR, NIH, C3H and BALB/c mice were high responders to M. corti whereas CBA and 3 congenic strains sharing the B10 background (C57BL/10, B10.S, B10.G) were low responders. Some of the genes for high eosinophil responsiveness appeared to be dominant, as F1 hybrids from high and low response parental strains were intermediate to high in response to infection. SJL and NIH strains were highly susceptible to infection with M. corti, larval burdens at 21 days after infection with 100 tetrathyridia being considerably higher (greater than 1000) than all other strains. BALB/c (congruent to 700 larvae) were designated susceptible, SWR (greater than 400 larvae) were resistant and the B10 congenics (less than 400 larvae) were highly resistant. Genes influencing resistance also appeared to be dominant, as F1 hybrids between resistant and susceptible parental strains were intermediate to resistant on infection. The overall response patterns indicate a direct correlation between susceptibility to infection and high eosinophil responsiveness, but this relationship is not consistent in all strains.

The effect of histamine on the induction of experimental autoimmune hemolytic anemia on OF1, BALB/c and SJL mice

Erythrocyte autoantibodies can be elicited in mice by injection of rat red blood cells (RBC) which are cross-reactive with mouse RBC. In this report, we show that histamine injected in vivo delayed the production of autoantibodies among BALB/c and OF1 mice. In contrast, the induction of autoantibodies in SJL mice was not affected by histamine. Furthermore, histamine did not affect the production of anti-rat RBC. Cimetidine (anti-H2) but not diphenhydramine (anti-H1) inhibited the histamine effect.

Immunological relationships during primary infection with Heligmosomoides polygyrus (Nematospiroides dubius): expulsion of adult worms from fast responder syngeneic and hybrid strains of mice

The time-course of low and high intensity primary infections with Heligmosomoides polygyrus was monitored in SJL and SWR mice, both of which usually expel worms within 7 weeks of larval administration. Worm expulsion in these strains was not dependent on the intensity of infection, with low and high intensity worm burdens being lost within the same period of time. The ability to expel worms rapidly was inherited in a dominant manner in F1 offspring of SJL or SWR mice mated with C57Bl10 mice; the latter being a strain in which no loss of worms was evident within 10 weeks of infection. However, neither (SJL x C57Bl10)F1 nor (SWR x C57Bl10)F1 mice expelled worms as rapidly as the parental SJL and SWR strains. (SWR x B10G)F1 [H-2q] mice eliminated worms faster than (SWR x C57Bl10)F1 [H-2bq], suggesting that the b haplotype had a moderating influence on the expulsion process. In fact (SWR x B10G)F1 mice showed a significant reduction in worm burdens by week 4 but by weeks 6-8 the rate of worm loss had slowed considerably. In contrast, SJL and SWR mice, whilst initiating rejection slightly later, (after week 4) expelled all worms within the following 2 weeks. Thus two distinct patterns of response were observed among the fast responder strains as exemplified by SWR and SJL mice on the one hand and (SWR x B10G)F1 on the other. Our results support the hypothesis that the course of a primary infection with H. polygyrus is influenced by multiple host gene loci, some of which are encoded within the MHC. SJL and SWR mice probably have similar if not identical gene combinations at loci which determine a fast responder phenotype, distinguishing them from the other mouse strains which have been studied.

Sensitization of T and B cells by a normally tolerogenic macromolecule: the induction of unresponsiveness and of sensitization is polymorphic

Changes induced in B and T cells by tolerogen were experimentally defined in animals which resist down-regulation. Female A/J, C57BL/6J, MLR/MpJ-lpr/lpr, MLR/MpJ-+/+ and NZB/B1NJ mice were injected at various ages with a tolerogenic form of rabbit gamma globulin (sRGG) or were left uninjected, and all were then immunized with dinitrophenylated RGG (DNP-RGG) on alum. The degree of tolerance was estimated by measuring anti-DNP and anti-RGG spleen plaque-forming cell (PFC) numbers. In some cases, the state of T or B cells deduced from these experiments was further examined by cell transfer experiments. Four types of responsiveness to the tolerogenic form of RGG (sRGG) were distinguished: 1) persistent tolerance inducibility of T and B cells to tolerance induction (A/J); 2) T cells retaining tolerance-inducibility after initiation of age-dependent sensitization of B cells by the tolerogenic form of RGG (C57BL/6J, NZB/B1NJ); 3) age-dependent resistance of T cells to tolerance-induction and age-dependent sensitization of B cells by tolerogen, with the sensitization only manifesting itself in reactivity with T cells from immunized donors (SJL/J); and 4) sensitization of T cells by a usually tolerogenic form of RGG (MLR/MpJ-lpr-lpr). Thus, the development of resistance against tolerance induction is highly polymorphic, not only with respect to the age of onset, but also with respect to the cellular site of its first manifestation and the effect. Possible mechanisms of B-cell sensitization in sRGG-treated C57BL/6 and NZB mice are discussed in relation to the age-dependent emergence of a B-cell subpopulation and of non-specific helper T-cell factors.

Sensitized spleen B-cells in tolerance-resisting SJL mice

A subpopulation of B-cells becomes sensitized in the 15-week-old SJL mouse, exposed to aggregate-freed rabbit gamma-globulin, which is highly tolerogenic when given to younger animals. This state of activation can only be expressed in collaboration with sensitized T-cells. The sensitized B-cell does not play an important role in the response of the intact 15-week-old SJL mouse, since there are no sensitized T-cells in the sRGG-treated animals.

Accelerated development of Th-2 type of helper effect in MRL/MpJ-lpr/lpr and BXSB/MpJ mice

Age-dependent changes, during adult life, in suppressor capacity and B cell responsiveness have been known for some time. In this paper, an age dependent change in helper function, is being reported. A Th-2 type of helper effect can be observed in tissue culture of spleen cells from animals sensitized with a macromolecule. An indirect plaque-forming response to the hapten occurs when the spleen cells are exposed to the sensitizing macromolecule and to the hapten conjugated to a carrier, structurally unrelated to the sensitizing macromolecule. There is considerable polymorphism in the age at which this effect is first demonstrable and at which it reaches mature levels. Mice of inbred stains, with various defects in the suppressor cell circuit (SJL/J, MRL/MpJ-lpr/lpr, BXSB/MpJ show an accelerated development of Th-2 helper capacity in the indirect plaque-forming response.