Autoantibody-secreting Plaque Forming Cells in Spleen and Thymus of NZB and Normal Mice

NZB mice develop several manifestations of autoimmune disease and, in particular, Coombs positive haemolytic anaemia¹ which can be accompanied by hepatosplenomegaly, glomerulonephritis and the appearance of antinuclear antibodies. The anaemia is associated with erythrocyte autoantibodies detected by direct and indirect antiglobulin tests and which from 3–4 months of age appear in an increasing proportion of mice until virtually all are involved by 9–12 months. Although there has been a good deal of work on the various disorders in NZB mice, the aetiology of the disease remains obscure². The thymus has been suggested as the site of origin of the disease³ and recently a viral cause for the autoimmune state was proposed⁴, but this evidence for these hypotheses has been equivocal^5–7. Although the spleen has been implicated as the chief site of autoantibody production⁸, no direct demonstration of the autoantibody secreting cells in NZB mice has been reported.     

A novel mouse Chr5 locus <Emphasis Type="Italic">Diht</Emphasis> controls dopamine-induced hypothermia

Mice of the strain C3H.PRI-Flv^r, carrying genetically determined resistance to flaviviruses, have been shown to be more sensitive to the hypothermic effect of dopamine than congenic flavivirus-susceptible C3H/HeJARC mice. In the current study, the greater sensitivity to dopamine-induced hypothermia observed in flavivirus-resistant mice was shown to be dose-dependent, with strain differences being the most prominent at a moderate dose of apomorphine (1 mg/kg). In addition, hypothermic responses to apomorphine were shown to be under developmental regulation; aging increased the potency of apomorphine-induced hypothermia and abrogated strain and sex differences observed in young mice. Linkage analysis of mouse strain-dependent co-inheritance between flavivirus resistance and greater sensitivity to the hypothermic effect of dopamine was performed using two genetically unrelated flavivirus-susceptible and two highly congenic flavivirus-resistant mouse strains in parallel with C3H.PRI-Flv^r-and C3H/HeJARC reference strains. This study has revealed a clear segregation between flavivirus resistance conferred by the Flv locus and sensitivity to dopamine-controlled hypothermia conferred by a novel locus, Diht. Parallel studies in F1 and F2 heterozygote mice showed that the high sensitivity to hypothermic effect of dopamine (Diht^high) is inherited as the Chr5-linked dominant trait. The novel locus, Diht, has been mapped proximal to the Flv locus on a distal part of mouse Chr5 between microsatellite markers D5Mit41 and D5Mit158.     

IL-10 Production Is Critical for Sustaining the Expansion of CD5+ B and NKT Cells and Restraining Autoantibody Production in Congenic Lupus-Prone Mice

The development and progression of systemic lupus erythematosus is mediated by the complex interaction of genetic and environmental factors. To decipher the genetics that contribute to pathogenesis and the production of pathogenic autoantibodies, our lab has focused on the generation of congenic lupus-prone mice derived from the New Zealand Black (NZB) strain. Previous work has shown that an NZB-derived chromosome 4 interval spanning 32 to 151 Mb led to expansion of CD5⁺ B and Natural Killer T (NKT) cells, and could suppress autoimmunity when crossed with a lupus-prone mouse strain. Subsequently, it was shown that CD5⁺ B cells but not NKT cells derived from these mice could suppress the development of pro-inflammatory T cells. In this paper, we aimed to further resolve the genetics that leads to expansion of these two innate-like populations through the creation of additional sub-congenic mice and to characterize the role of IL-10 in the suppression of autoimmunity through the generation of IL-10 knockout mice. We show that expansion of CD5⁺ B cells and NKT cells localizes to a chromosome 4 interval spanning 91 to 123 Mb, which is distinct from the region that mediates the majority of the suppressive phenotype. We also demonstrate that IL-10 is critical to restraining autoantibody production and surprisingly plays a vital role in supporting the expansion of innate-like populations.     

Cd-Resistant Strains of B. cereus S5 with Endurance Capacity and Their Capacities for Cadmium Removal from Cadmium-Polluted Water

The goal of this study was to identify Cd-resistant bacterial strains with endurance capacity and to evaluate their ability to remove cadmium ions from cadmium-polluted water. The Bacillus cereusS5 strain identified in this study had the closest genetic relationship with B. cereus sp. Cp1 and performed well in the removal of Cd²⁺ions from solution. The results showed that both the live and dead biomasses of the Cd²⁺-tolerant B. cereus S5 strain could absorb Cd²⁺ ions in solution but that the live biomass of the B. cereus S5 strain outperformed the dead biomass at lower Cd²⁺concentrations. An analysis of the cadmium tolerance genes of B. cereus S5 identified ATPase genes that were associated with cadmium tolerance and involved in the ATP pumping mechanism. The FTIR spectra revealed the presence of amino, carboxyl and hydroxyl groups on the pristine biomass and indicated that the cadmium ion removal ability was related to the structure of the strain. The maximum absorption capacity of the B. cereus S5 strain in viable spore biomass was 70.16 mg/g (dry weight) based on a pseudo-second-order kinetic model fit to the experimental data. The Langmuir and Langmuir-Freundlich isotherm adsorption models fit the cadmium ion adsorption data well, and the kinetic curves indicated that the adsorption rate was second-order. For Cd²⁺ concentrations (mg/L) of 1–109 mg/L, good removal efficiency (>80%) was achieved using approximately 3.48–10.3 g/L of active spore biomass of the B. cereus S5 strain. A cadmium-tolerant bacteria-activated carbon-immobilized column could be used for a longer duration and exhibited greater treatment efficacy than the control column in the treatment of cadmium-polluted water. In addition, a toxicity assessment using mice demonstrated that the biomass of the B. cereus S5 strain and its fermentation products were non-toxic. Thus, the isolated B. cereus S5 strain can be considered an alternative biological adsorbent for use in emergency responses to severe cadmium pollution and in the routine treatment of trace cadmium pollution.     

Activity and Properties of Macrophage Migration Inhibitory Factor produced by Mixed Lymphocyte Cultures

THE macrophage migration test is an in vitro demonstration of delayed hypersensitivity. Supernatant fluids of sensitive lymphocytes cultured for 24 h in the presence of specific antigen contain migration inhibitory factor (MIF) that arrests the migration of macrophages of unsensitized animals in vitro¹,². In vivo, it induces delayed skin reactions³. The use of the macrophage migration test, based on differences of transplantation antigens in donor and recipient, to show histocompatibility has been suggested⁴. The test was also recommended as an indicator of immunological reactivity after organ transplantation, to demonstrate impending rejection⁵. It can demonstrate homograft sensitivity, for migration of peritoneal exudate cells (containing lymphocytes and macrophages) of CBA mice previously sensitized by grafts from A/Jax donors was inhibited when they were mixed with peritoneal exudate cells of the donor strain. However, histocompatibility was not demonstrated, for mixtures of peritoneal exudate cells of ungrafted CBA mice and A/Jax mice migrated regularly during the 24 h test⁶.     

Epithelial V-Like Antigen Mediates Efficacy of Anti-Alpha4 Integrin Treatment in a Mouse Model of Multiple Sclerosis

Natalizumab inhibits the transmigration of activated T lymphocytes into the brain and is highly efficacious in multiple sclerosis (MS). However, from a pharmacogenomic perspective, its efficacy and safety in specific patients remain unclear. Here our goal was to analyze the effects of epithelial V-like antigen (EVA) on anti-alpha₄ integrin (VLA4) efficacy in a mouse model of MS, experimental autoimmune encephalomyelitis (EAE). EVA has been previously characterized in human CD4 T lymphocytes, mouse thymic development, and choroid plexus epithelial cells. Further analysis here demonstrated expression in B lymphocytes and an increase in EVA⁺ lymphocytes following immunization. Following active induction of EAE using the MOG^35–55 active immunization model, EVA deficient mice developed more severe EAE and white matter tissue injury as compared to wild type controls. This severe EAE phenotype did not respond to anti-VLA4 treatment. In both the control antibody and anti-VLA4 conditions, these mice demonstrated persistent CNS invasion of mature B lymphocyte (CD19⁺, CD21⁺, sIgG⁺), increased serum autoantibody levels, and extensive complement and IgG deposition within lesions containing CD5⁺IgG⁺ cells. Wild type mice treated with control antibody also demonstrated the presence of CD19⁺, CD21⁺, sIgG⁺ cells within the CNS during peak EAE disease severity and detectable serum autoantibody. In contrast, wild type mice treated with anti-VLA4 demonstrated reduced serum autoantibody levels as compared to wild type controls and EVA-knockout mice. As expected, anti-VLA4 treatment in wild type mice reduced the total numbers of all CNS mononuclear cells and markedly decreased CD4 T lymphocyte invasion. Treatment also reduced the frequency of CD19⁺, CD21⁺, sIgG⁺ cells in the CNS. These results suggest that anti-VLA4 treatment may reduce B lymphocyte associated autoimmunity in some individuals and that EVA expression is necessary for an optimal therapeutic response. We postulate that these findings could optimize the selection of treatment responders.     

Early IFN-Gamma Production after YF 17D Vaccine Virus Immunization in Mice and Its Association with Adaptive Immune Responses

Yellow Fever vaccine is one of the most efficacious human vaccines ever made. The vaccine (YF 17D) virus induces polyvalent immune responses, with a mixed T_H1/T_H2 CD4⁺ cell profile, which results in robust T CD8⁺ responses and high titers of neutralizing antibody. In recent years, it has been suggested that early events after yellow fever vaccination are crucial to the development of adequate acquired immunity. We have previously shown that primary immunization of humans and monkeys with YF 17D virus vaccine resulted in the early synthesis of IFN-γ. Herein we have demonstrated, for the first time that early IFN-γ production after yellow fever vaccination is a feature also of murine infection and is much more pronounced in the C57BL/6 strain compared to the BALB/c strain. Likewise, in C57BL/6 strain, we have observed the highest CD8⁺ T cells responses as well as higher titers of neutralizing antibodies and total anti-YF IgG. Regardless of this intense IFN-γ response in mice, it was not possible to see higher titers of IgG2a in relation to IgG1 in both mice lineages. However, IgG2a titers were positively correlated to neutralizing antibodies levels, pointing to an important role of IFN-γ in eliciting high quality responses against YF 17D, therefore influencing the immunogenicity of this vaccine.     

Measurement of Tactile Allodynia in a Murine Model of Bacterial Prostatitis

Uropathogenic Escherichia coli (UPEC) are pathogens that play an important role in urinary tract infections and bacterial prostatitis¹. We have recently shown that UPEC have an important role in the initiation of chronic pelvic pain², a feature of Chronic prostatitis/Chronic pelvic pain syndrome (CP/CPPS)^3,4. Infection of the prostate by clinically relevant UPEC can initiate and establish chronic pain through mechanisms that may involve tissue damage and the initiation of mechanisms of autoimmunity⁵.A challenge to understanding the pathogenesis of UPEC in the prostate is the relative inaccessibility of the prostate gland to manipulation. We utilized a previously described intraurethral infection method⁶ to deliver a clinical strain of UPEC into male mice thereby establishing an ascending infection of the prostate. Here, we describe our protocols for standardizing the bacterial inoculum⁷ as well as the procedure for catheterizing anesthetized male mice for instillation of bacteria.CP/CPPS is primarily characterized by the presence of tactile allodynia⁴. Behavior testing was based on the concept of cutaneous hyperalgesia resulting from referred visceral pain^8-10. An irritable focus in visceral tissues reduces cutaneous pain thresholds allowing for an exaggerated response to normally non-painful stimuli (allodynia). Application of normal force to the skin result in abnormal responses that tend to increase with the intensity of the underlying visceral pain. We describe methodology in NOD/ShiLtJ mice that utilize von Frey fibers to quantify tactile allodynia over time in response to a single infection with UPEC bacteria.     

Regulatory role of CD1d in neurotropic virus infection

The GDVII strain of Theiler's murine encephalomyelitis virus (TMEV) causes an acute fatal polioencephalomyelitis in mice. Infection of susceptible mice with the DA strain of TMEV results in an acute polioencephalomyelitis followed by chronic immune-mediated demyelination with virus persistence in the central nervous system (CNS); DA virus infection is used as an animal model for multiple sclerosis. CD1d-restricted natural killer T (NKT) cells can contribute to viral clearance and regulation of autoimmune responses. To investigate the role of CD1d in TMEV infection, we first infected CD1d-deficient mice (CD1^−/−) and wild-type BALB/c mice with GDVII virus. Wild-type mice were more resistant to virus than CD1^−/− mice (50% lethal dose titers: wild-type mice, 10 PFU; CD1^−/− mice, 1.6 PFU). Wild-type mice had fewer viral antigen-positive cells with greater inflammation in the CNS than CD1^−/− mice. Second, an analysis of DA virus infection in CD1^−/− mice was conducted. Although both wild-type and CD1^−/− mice had similar clinical signs during the first 2 weeks after infection, CD1^−/− mice had an increase in neurological deficits over those observed in wild-type mice at 3 to 5 weeks after infection. Although wild-type mice had no demyelination, 20 and 60% of CD1^−/− mice developed demyelination at 3 and 5 weeks after infection, respectively. TMEV-specific lymphoproliferative responses, interleukin-4 (IL-4) production, and IL-4/gamma interferon ratios were higher in CD1^−/− mice than in wild-type mice. Thus, CD1d-restricted NKT cells may play a protective role in TMEV-induced neurological disease by alteration of the cytokine profile and virus-specific immune responses.     

Construction and immunogenicity of recombinant pseudorabies virus expressing the modified GP5m protein of porcine reproduction and respiratory syndrome virus

Pseudorabies virus (PRV), an alpha-herpesvirus, has been developed as a live viral vector for animal vaccines. However, the PRV recombinant virus TK⁻/gE⁻/GP5⁺ expressing GP5 of porcine reproductive and respiratory syndrome virus (PRRSV), based on the PRV genetically depleted vaccine strain TK⁻/gE⁻/LacZ⁺, scarcely stimulated the vaccinated animals to produce neutralizing antibodies against PRRSV. To develop a booster-specific immune response of such PRV recombinants, the ORF5m gene (the modified ORF5 gene having better immune responses) was substituted for the ORF5 gene and introduced into PRV TK⁻/gE⁻/LacZ⁺, resulting in a PRV recombinant named TK⁻/gE⁻/GP5m⁺, which expressed the modified GP5m protein. The recombinant virus was confirmed using PCR, Southern blotting and Western blotting. TK⁻/gE⁻/GP5m⁺ and TK⁻/gE⁻/GP5⁺ expressing the authentic GP5 protein were inoculated into Balb/c mice to evaluate their immune responses. The results indicated that the protecting neutralization antibodies (the 3/6 vaccinated mice obtained 1:16) and cell immune responses induced by TK⁻/gE⁻/GP5m⁺ against PRRSV were higher than that induced by TK⁻/gE⁻/GP5⁺. Thus, the development of the new PRV recombinant expressing the modified GP5m protein as a candidate vaccine established the basis for the study of bivalent genetic engineering vaccines against PRRSV and PRV. Translated from Journal of Biotechnology, 2005, 21(6): 858–864 [译自: 生物工程学报]     

Depletion of glycosphingolipids induces excessive response of chondrocytes under mechanical stress

Glycosphingolipids (GSLs) are ubiquitous membrane components that play an indispensable role in maintaining chondrocyte homeostasis. To gain better insight into roles of GSLs, we studied the effects of GSL-deletion on the physiological responses of chondrocytes to mechanical stress. Mice lacking Ugcg gene (Ugcg^-/-) were genetically generated to obtain GSL-deficient mice, and their chondrocytes from the joints were used for functional analyses in vitro culture experiments. The cells were seeded in a three-dimensional collagen gel and subjected to 5%, 10% or 16% cyclic tensile strain for either 3 or 24 h. The gene expressions of chondrocyte anabolic and catabolic factors, and the induction of Ca²⁺ signaling were analyzed. Our results revealed that chondrocytes derived from GSL-deficient mice exhibited an elevation in the expression of catabolic factors (ADAMTS-5, MMP-13) following the exposure to strain with amplitudes of 10%. Likewise, applying cyclic tensile strain with these amplitudes resulted in an increased Ca²⁺ oscillation ratio in chondrocytes from GSL-deficient as compared to the ratio from control mice. These results demonstrated that deletion of GSL stimulated the catabolic responses of chondrocytes to mechanical stress via the augmentation of the sensitivity to mechanical stress that may lead to the cartilage deterioration. These findings suggest that the regulation of the physiological responses of chondrocytes by GSLs could be a potential target in a therapeutic intervention in osteoarthritis.     

Genetic control of anti-Sm autoantibody production in NOD congenic mice narrowed to the Idd9.3 region

Anti-Smith (anti-Sm) autoantibodies are directed to proteins in the small-nuclear ribonucleoprotein (snRNP) family and are considered specific for systemic lupus erythematosus (SLE) in both humans and mice. We previously established that NOD.c3c4 mice, carrying B6 and B10 congenic segments from chromosomes 3 to 4 on an nonobese diabetic (NOD) background, and NOD.Idd9R28 mice, carrying a B10 segment on c4 alone, developed significant penetrance of anti-Sm antibody production. Here we determine autoantibody incidence in additional NOD.Idd9 congenic strains and use a congenic mapping approach to narrow the interval necessary for enhanced autoantibody production to a ∼5.6-Mb region containing insulin-dependent diabetes (Idd)9.3. The Idd9.3 interval contains the candidate molecule cluster of differentiation (CD)137, which is a member of the tumor necrosis factor (TNF) receptor superfamily, functions as an inducible costimulator of T cells, and controls T–B interactions. The NOD and B10 CD137 alleles have sequence polymorphisms and different functional effects on T cells; the NOD CD137 allele mediates weaker T cell proliferative responses and decreased interleukin (IL)-2 production after CD137-mediated costimulation. Our work establishes CD137 as a candidate gene for control of autoantibody production in NOD.Idd9.3 congenic mice.     

Optogenetic Stimulation of the Auditory Nerve

Direct electrical stimulation of spiral ganglion neurons (SGNs) by cochlear implants (CIs) enables open speech comprehension in the majority of implanted deaf subjects^1-6. Nonetheless, sound coding with current CIs has poor frequency and intensity resolution due to broad current spread from each electrode contact activating a large number of SGNs along the tonotopic axis of the cochlea^7-9. Optical stimulation is proposed as an alternative to electrical stimulation that promises spatially more confined activation of SGNs and, hence, higher frequency resolution of coding. In recent years, direct infrared illumination of the cochlea has been used to evoke responses in the auditory nerve¹⁰. Nevertheless it requires higher energies than electrical stimulation^10,11 and uncertainty remains as to the underlying mechanism¹². Here we describe a method based on optogenetics to stimulate SGNs with low intensity blue light, using transgenic mice with neuronal expression of channelrhodopsin 2 (ChR2)¹³ or virus-mediated expression of the ChR2-variant CatCh¹⁴. We used micro-light emitting diodes (µLEDs) and fiber-coupled lasers to stimulate ChR2-expressing SGNs through a small artificial opening (cochleostomy) or the round window. We assayed the responses by scalp recordings of light-evoked potentials (optogenetic auditory brainstem response: oABR) or by microelectrode recordings from the auditory pathway and compared them with acoustic and electrical stimulation.     

CpG or IFN-α are more potent adjuvants than GM-CSF to promote anti-tumor immunity following idiotype vaccine in multiple myeloma

Idiotype (Id) protein in combination with GM-CSF has been used as vaccines for immunotherapy of patients with myeloma and B-cell tumors and the results have been disappointing. To search for better immune adjuvants to improve the efficacy of Id-based immunotherapy in myeloma, we evaluated and compared the efficacy of vaccination of Id protein in combination with CpG or IFN-α, or GM-CSF as a control, in the 5TGM1 myeloma mouse model. Our results showed that Id vaccine combined with CpG or IFN-α, but not GM-CSF, not only efficiently protected mice from developing myeloma but also eradicated established myeloma. The therapeutic responses were associated with an induction of strong humoral immune responses including anti-Id antibodies, and cellular immune responses including Id- and myeloma-specific CD8⁺ cytotoxic T lymphocytes (CTLs), CD4⁺ type-1 T-helper (Th1) cells and memory T cells in mice receiving Id vaccine combined with CpG or IFN-α. Furthermore, Id vaccine combined with CpG or IFN-α induced Id- and tumor-specific memory immune responses that protected surviving mice from tumor rechallenge. Thus, our study clearly shows that CpG or IFN-α are better immune adjuvants than GM-CSF. This information will be important for improving the strategies of Id-based immunotherapy for patients with myeloma and other B-cell tumors.     

Genetic Regulation of Plasma Corticosterone Concentration and its Response to Castration and Allogeneic Tumour Growth in the Mouse

EXCESS fat deposition after castration is thought to be a response to hyperinsulinism induced by an increased level of adrenal glucocorticoids¹. Two mutant alleles, lethal yellow (A^y) and viable yellow (A^vy), at the agouti locus in the mouse induce excess fat deposition; the A^y allele has also been found to induce insulin resistance². Katsh³ concluded that in adrenalectomized KL strain mice a considerable portion of the high insulin tolerance depended on normal adrenal function. In the inbred YS/Wf and VY/Wf strains, both yellow pheno-types modulate serum insulin concentration⁴. Castration of inbred YS strain males causes a large decrease in serum insulin⁴, suggesting a possible relationship¹ to the concentration of adrenal glucocorticoids. Growth of allogeneic tumour cells has different effects on the serum insulin concentrations of YS and VY strain mice⁴.     

A Listeria ivanovii balanced-lethal system may be a promising antigen carrier for vaccine construction

Expressing heterologous antigens by plasmids may cause antibiotic resistance. Additionally, antigen expression via plasmids is unstable due to the loss of the plasmid. Here, we developed a balanced-lethal system. The Listeria monocytogenes (LM) balanced-lethal system has been previously used as an antigen carrier to induce cellular immune response. However, thus far, there has been no reports on Listeria ivanovii (LI) balanced-lethal systems. The dal and dat genes from the LI-attenuated LIΔatcAplcB (LIΔ) were deleted consecutively, resulting in a nutrient-deficient LIΔdd strain. Subsequently, an antibiotic resistance-free plasmid carrying the LM dal gene was transformed into the nutrient-deficient strain to generate the LI balanced-lethal system LIΔdd:dal. The resultant bacterial strain retains the ability to proliferate in phagocytic cells, as well as the ability to adhere and invade hepatocytes. Its genetic composition was stable, and compared to the parent strain, the balanced-lethal system was substantially attenuated. In addition, LIΔdd:dal induced specific CD4⁺/CD8⁺ T-cell responses and protected mice against LIΔ challenge. Similarly, we constructed an LM balanced-lethal system LMΔdd:dal. Sequential immunization with different recombinant Listeria strains will significantly enhance the immunotherapeutic effect. Thus, LIΔdd:dal combined with LMΔdd:dal, or with other balanced-lethal systems will be more promising alternative for vaccine development.     

Inheritance of an isoelectrically focused spectrotype linked to theIg-1 b allotype

The primary anti-NP response in C57BL/6 and CBA mice was analyzed by isoelectric focusing. Antibody responses in C57 mice were restricted in heterogeneity and over 80 % of this strain shared an isoelectric focusing spectrum characteristic of an homogeneous antibody (spectrotype). This spectrotype N-l was inherited as a dominant characteristic in (CBA×C57)F₁ mice, and backcross analysis revealed that it was genetically linked to the heavy chain allotypeIg-1 ^b . It thus behaved as a marker similar to the fine specificity characteristic of heteroclitic antibody. Elution studies showed that antibody with the spectrotype N-1 was heteroclitic, with a higher affinity for NIP and NNP than for the immunogen NP. It is argued that a) a single germ-lineV gene (designated N-1) codes for the V_H region of this antibody and b) in C57BL/6 mice this geneV _H N-1 is closely linked toIg-1 ^b .Abbreviations BSA bovine serum albumin - CG Chicken globulin - NP (4-Hydroxy-3-nitrophenyl)acetyl - NIP (4-Hydroxy-5-iodo-3-nitrophenyl)acetyl - NBrP (4 Hydroxy-5-bromo-3-nitrophenyl)acetyl - NNP (4-Hydroxy-3,5-dinitrophenyl)acetyl - NIP-Cap NIP-aminocaproate - I₅₀ Hapten concentration causing 50% inhibition of antigen binding - SRC Sheep red cells - IEF Isoelectric focusing - PBS Phosphate buffered saline, pH 7.4     

Non-H-2 and H-2-Linked immune response genes control the cytotoxic T-cell response to H-Y

The immunoregulation of cytotoxic T-cell responses to the male-specific antigen H-Y in mice has been found to be genetically controlled by genes of the major histocompatibility complex (H-2). Responsiveness was mainly confined to H-2 ^b strains, but it has also been found in recombinant strains, F₁ hybrids, and chimeras that carry at least part of the H-2 ^b haplotype. By using a different immunization procedure it has been shown recently that an H-2 ^k mouse strain (CBA) is also able to mount an equivalent H-Y-specific response. We investigate here, by applying this immunization technique, the responsiveness of other H-2 ^k strains and of strains of other independent H-2 haplotypes. Both responders and nonresponders are found in three haplotypes: k, s, and d. The strain distribution pattern of responsiveness shows a combined influence of non-H-2 and H-2 genes. In certain strains there is a high variability in responsiveness between genetically indentical individual animals. We discuss a model of immune response (Ir) gene function which could account for these observations.     

Evaluation of a New Tumor Necrosis Factor-α-Inducing Membrane Protein of Helicobacter pylori as a Prophylactic Vaccine Antigen

Background: Tumor necrosis factor (TNF)‐α‐inducing protein (Tipα) is a newly identified carcinogenic factor present in Helicobacter pylori. Tipα has the unique function of inducing TNF‐α production by gastric cells in vitro and is assumed to be related with the development of gastritis and gastric cancer. We investigated the effects of vaccination with Tipα against H. pylori infection and analyzed the immune responses. Methods: C57BL/6 mice were immunized via the intranasal route with CpG, recombinant Tipα + CpG, and recombinant del‐Tipα (a mutant of Tipα) + CpG. Eight weeks after the mice were infected with H. pylori (5 × 10⁷ CFU), the number of colonizing bacteria in the stomach was calculated, and the histological severity of gastritis was evaluated. Levels of Tipα‐specific IgG and IgA antibodies in mouse serum were measured by an enzyme‐linked immunosorbent assay (ELISA). Local production of cytokines including Interleukin (IL)‐10, TNF‐α and Interferon (IFN)‐γ in gastric mucosa was also measured by real time‐PCR. Results: Levels of Tipα‐specific antibodies were significantly higher in Tipα‐immunized and del‐Tipα‐immunized mice than in the infection control group. The numbers of colonizing bacteria were significantly reduced in Tipα‐immunized mice (4.29 × 10⁵ CFU/g) and del‐Tipα immunized mice (2.5 × 10⁵ CFU/g) compared with infection control mice (5.7 × 10⁶ CFU/g). The levels of IFN‐γ and IL‐10 were significantly higher in del‐Tipα‐immunized mice than the infection control group. Conclusion: Vaccinations with Tipα and del‐Tipα were effective against H. pylori infection. The inhibition of H. pylori colonization is associated mainly with Th1 cell‐mediated immunity.     

Prenatal TCDD causes persistent modulation of the postnatal immune response, and exacerbates inflammatory disease, in 36-week-old lupus-like autoimmune SNF1 mice

BACKGROUND: Prenatal exposure to the persistent environmental pollutant and model Ah receptor agonist, 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD), has been shown to permanently suppress postnatal cell‐mediated immunity. More recently, skewing of select adult T and B cell responses toward enhanced inflammation has also been described in C57BL/6 mice after prenatal TCDD. This raises questions about adverse postnatal immune consequences of prenatal TCDD in animals genetically predisposed to inappropriate inflammatory responses. METHODS: Lupus‐prone SNF₁ mice were exposed to 0, 40, or 80 µg/kg TCDD on gestation day (gd) 12 and examined at 36 weeks‐of‐age for immunomodulatory effects that correlated with worsened lupus pathology. RESULTS: Bone marrow pro‐ and large pre‐B cells were decreased by prenatal TCDD, in both adult male and female mice, as were pre‐ and immature B cells. Splenic CD23⁻CD1^hi and CD19⁺CD5⁺ B cells were increased in males, as were B220^hi B cells in females, further suggesting persistent disruption of B cell lymphopoiesis by prenatal TCDD. Female mice displayed decreased IL‐10 production by ConA‐activated splenocytes, while males underproduced IL‐4. Autoreactive CD4⁺Vβ17a⁺ spleen T cells were increased in both sexes by 80 µg/kg TCDD. Male mice but not females showed increased anti‐ds DNA and cardiolipin autoantibody levels. CONCLUSIONS: Prenatal TCDD augmented the hallmark indicators of SLE progression in the lupus‐prone SNF₁ mice, including renal immune complex deposition, glomerulonephritis, and mesangial proliferation. Prenatal TCDD therefore caused persistent modulation of the postnatal immune response, and exacerbated inflammatory disease, in lupus‐like autoimmune SNF₁ mice. Birth Defects Res (Part B) 92:82–94, 2011. © 2011 Wiley‐Liss, Inc.