Establishment and characterization of murine models of asthma and subcutaneous immunotherapy for Humulus pollen allergy.

INTRODUCTION: Humulus pollen is an important cause of allergic asthma in East Asia. There have been some murine models for Humulus pollen allergy established by intraperitoneal (IP) sensitization and nasal drip stimulation, but they were not comprehensive enough. Here, we used atomized inhalation for challenge and compared the subcutaneous (SC) and IP sensitization routes to determine the optimal method to establish a model of asthma induced by Humulus pollen. Subsequently, we tried to develop a rapid subcutaneous immunotherapy (SCIT) model for Humulus allergy. METHODS: BALB/c Mice were sensitized through the SC or IP route, with respective reference to previously established sensitization methods and allergen dosing, and challenged with nebulized Humulus pollen extract to induce asthma. To compare the two sensitization methods, airway hyperresponsiveness (AHR), inflammatory cell infiltration, allergen-specific serum immunoglobulin (Ig)E (sIgE) levels, cytokine levels, and lung histopathology were assessed. The effects of SCIT (once every other day for 16 days) on airway inflammation, AHR, sIgE, and allergen-specific serum IgG2a (sIgG2a) levels were evaluated by using the model established in this study. RESULTS: Although mice sensitized by the SC or IP routes both showed AHR and airway inflammation, the SC route elicited significantly higher levels of sIgE, eosinophil inflammation, and T helper type 2 cytokines, compared with the IP route. SCIT in the treatment group significantly reduced the titers of sIgE, enhanced the titers of sIgG2a, and effectively alleviated pulmonary inflammation and AHR, compared with the vehicle group. CONCLUSIONS: The SC route can be used to establish a murine model of Humulus pollen allergy that recapitulates the characteristics of clinical allergic asthma. Short-term SCIT can significantly improve symptoms and pathophysiology in asthmatic mice.

Identification of a linear epitope for Fc-binding in the mouse FcγRIII.

Fc receptors are transmembrane proteins, found on the surfaces of immune cells, that aid in the removal of foreign pathogens by binding to antibody-coated targets via the Fc regions of the antibodies. To identify sites on mouse FcgammaRIII (moFcgammaRIII) alpha-chain that bind to the Fc region, peptides derived from the proximal extracellular domain (EC2) of moFcgammaRIII alpha-chain corresponding to the homologous region of human FcgammaRIIIB alpha-chain were synthesized. Binding of mouse IgG to the different peptides was tested by Dot-blot assay. The effective peptide (119)SFFHNEKSVRYH(130) located in the putative C-C' loop of the EC2 domain was found to bind mouse IgG specifically with an affinity of approximately 5.58 x 10(-5) M and inhibit the binding of mouse IgG to the receptor. Such a functional peptide should be very useful for further understanding the IgG-FcgammaR interaction and development of FcR-targeting drugs.

Decreased cutaneous resonance running time in cured leprosy subjects.

BACKGROUND/OBJECTIVES: Leprosy prominently involves both the skin and peripheral neural tissues and some symptoms persist after microbial cure. Because alterations in the dermis also occur in leprosy, we assessed here whether there were changes in cutaneous resonance running time (CRRT), a parameter that is influenced by collagen properties, in cured leprosy subjects. METHODS: A reviscometer was used to measure the CRRT at various directions on the dorsal hand and the flexural forearms of 76 cured leprosy subjects aged 50-85 years and 68 age-matched normal subjects. RESULTS: In comparison to normal subjects, CRRTs on the hands and the forearms were significantly reduced in all directions in cured leprosy, except at the 1-7, 2-8 and 3-9 o'clock directions on the forearms. CRRTs were reduced significantly at both the 4-10 and 5-11 o'clock directions on the forearm in lepromatous (73.33 +/- 4.19 at 4-10 o'clock and 67.44 +/- 2.71 at 5-11 o'clock direction) and borderline lepromatous types (77.58 +/- 5.84 at 4-10 o'clock and 79.85 +/- 6.81 at 5-11 o'clock direction) as compared with normal (143.10 +/- 7.75 at 4-10 o'clock and 125.18 +/- 8.14 at 5-11 o'clock direction). On the hand, CRRTs at all directions, except that at 4-10 o'clock direction, were also significantly reduced in lepromatous and borderline lepromatous types in comparison with normal. Significant differences in CRRT at some directions were found among the various subtypes of leprosy. CONCLUSION: CRRTs were abnormal in the cured leprosy subjects as a whole, but varied with leprosy subtypes, which suggested that the extent of reduction of CRRTs correlates with the severity of immune alteration. These results suggest that CRRT measurements could be a useful approach to quantify the extent of some residual abnormalities in cured leprosy and perhaps could also be used to evaluate the efficacy of treatment.

Immunogenicity in Mamu-A*01 rhesus macaques of a CCR5-tropic human immunodeficiency virus type 1 envelope from the primary isolate (Bx08) after synthetic DNA prime and recombinant adenovirus 5 boost.

Envelopes of primary R5-tropic human immunodeficiency virus type 1 (HIV-1) isolates may be particularly relevant for vaccine purposes and should be evaluated for immunogenicity in animals including macaques before carrying out human vaccine trials. In the present study, the immunogenicities of synthetic HIV-1 env DNA vaccines, which had been derived from the early primary isolate Bx08 and contain humanized codons, were evaluated in mice, guinea pigs and rhesus macaques. Neutralization sensitivity of the HIV-1(Bx08) isolate was found to resemble that of other primary isolate prototypes. Immunogenicity of gp120 delivered as codon-optimized DNA vaccine was comparable to that of recombinant gp120 protein plus adjuvant in mice. Similarly, DNA vaccination of guinea pigs with synthetic gp140(Bx08) and gp150(Bx08) DNA induced a strong antibody response independent of the gene construct and DNA immunization route. Mamu-A*01 rhesus macaques were DNA vaccinated with synthetic gp150(Bx08) or gp140(Bx08) DNA and boosted with a replication-deficient recombinant human adenovirus type 5 expressing a synthetic gp120(Bx08) gene. DNA-vaccinated rhesus macaques developed specific CD8+ T lymphocyte responses and anti-rgp120(IIIb) antibody responses. Both the humoral and cellular responses were significantly improved following intramuscular boosting with the recombinant adenovirus. The demonstrated humoral and cellular immunogenicities of these HIV Bx08 Env vaccines in non-human primates encourages their further development as one component in candidate HIV vaccines for humans.