Kamal Srivastava

Engineered Recombinant Peanut Protein and Heat-Killed Listeria monocytogenes Coadministration Protects Against Peanut-Induced Anaphylaxis in a Murine Model

Peanut allergy (PNA) is the major cause of fatal and near-fatal anaphylactic reactions to foods. Traditional immunotherapy using peanut (PN) protein is not an option for PNA therapy because of the high incidence of adverse reactions. We investigated the effects of s.c. injections of engineered (modified) recombinant PN proteins and heat-killed Listeria monocytogenes (HKLM) as an adjuvant on anaphylactic reactions in a mouse model of PN allergy. PN-allergic C3H/HeJ mice were treated s.c. with a mixture of the three major PN allergens and HKLM (modified (m)Ara h 1–3 plus HKLM). The effects on anaphylactic reactions following PN challenge and the association with Ab levels and cytokine profiles were determined. Although all mice in the sham-treated groups exhibited anaphylactic symptoms with a median symptom score of 3, only 31% of mice in the mAra h 1–3 plus HKLM group developed mild anaphylaxis, with a low median symptom score of 0.5. Alterations in core body temperature, bronchial constriction, plasma histamine, and PN-specific IgE levels were all significantly reduced. This protective effect was markedly more potent than in the mAra h 1–3 protein alone-treated group. HKLM alone did not have any protective effect. Reduced IL-5 and IL-13, and increased IFN-γ levels were observed only in splenocytes cultures from mAra h 1–3 plus HKLM-treated mice. These results show that immunotherapy with modified PN proteins and HKLM is effective for treating PN allergy in this model, and may be a potential approach for treating PNA.

Food Allergy Herbal Formula-2 silences peanut-induced anaphylaxis for a prolonged posttreatment period via IFN-γ-producing CD8+ T cells

BACKGROUND Food allergy is a serious and sometimes fatal condition for which there is no cure. We previously reported that Food Allergy Herbal Formula (FAHF)-2) protected peanut-allergic mice against anaphylactic reactions as long as 4 weeks posttherapy. This formula is now in clinical trials in the United States. OBJECTIVE We sought to determine whether FAHF-2-mediated protection could be extended long-term and explored the mechanisms underlying its persistent immunomodulatory effects. METHODS Peanut-allergic mice received FAHF-2 daily orally by gavage for 7 weeks, and then received 7 oral peanut challenges at intervals of 4 to 10 weeks over a period of 36 weeks. For mechanistic studies, some mice received CD4(+) or CD8(+) T-cell-depleting antibodies or IFN-gamma-neutralizing antibodies. Anaphylactic symptoms, body temperatures, and plasma histamine levels were recorded after each challenge, and peanut-specific immunoglobulin levels and cytokine profiles of splenocytes, mesenteric lymph node cells, and purified CD4(+) and CD8(+) T cells were determined. RESULTS Food Allergy Herbal Formula-2 treatment protected mice from anaphylaxis for more than 36 weeks after discontinuing treatment. Peanut-specific IgE levels were reduced as much as 50%, whereas IgG(2a) levels were increased as much as 60%, and these effects persisted over time. T(H)2 cytokine production by CD4(+) T cells from FAHF-2-treated mice was reduced as much as 75%, whereas CD8(+) T-cell IFN-gamma production was markedly increased by as much as 85% at the final challenge. Neutralization of INF-gamma and depletion of CD8(+) T cells markedly attenuated FAHF-2 efficacy. CONCLUSIONS Food Allergy Herbal Formula-2 provides long-term protection from anaphylaxis by inducing a beneficial shift in allergen-specific immune responses mediated largely by elevated CD8(+) T-cell IFN-gamma production.

Induction of tolerance after establishment of peanut allergy by the food allergy herbal formula‐2 is associated with up‐regulation of interferon‐γ

Background Peanut (PN)‐anaphylaxis is potentially life threatening. We previously reported that a Chinese herbal medicine preparation, food allergy herbal formula‐2 (FAHF‐2), prevented peanut allergy (PNA) in mice when administered during sensitization.

Effect of ageing on pulmonary inflammation, airway hyperresponsiveness and T and B cell responses in antigen‐sensitized and ‐challenged mice

Background The effect of ageing on several pathologic features of allergic asthma (pulmonary inflammation, eosinophilia, mucus hypersecretion), and their relationship with airway hyperresponsiveness (AHR) is not well characterized.

Maternal peanut exposure during pregnancy and lactation reduces peanut allergy risk in offspring.

BACKGROUND Maternal allergy is believed to be a risk factor for peanut allergy (PNA) in children. However, there is no direct evidence of maternal transmission of PNA susceptibility, and it is unknown whether maternal peanut exposure affects the development of PNA in offspring. OBJECTIVE To investigate the influence of maternal PNA on offspring reactions to the first peanut exposure, and whether maternal low-dose peanut exposure during pregnancy and lactation influences these reactions and peanut sensitization in a murine model. METHODS Five-week-old offspring of PNA C3H/HeJ mothers (PNA-Ms) were challenged intragastrically with peanut (first exposure), and reactions were determined. In a subset of the experiment, PNA-Ms were fed a low dose of peanut (PNA-M/PN) or not fed peanut (PNA-M/none) during pregnancy and lactation. Their 5-week-old offspring were challenged intragastrically with peanut, and reactions were determined. In another subset of the experiment, offspring of PNA-M/PN or PNA-M/none were sensitized with peanut intragastrically for 6 weeks, and serum peanut-specific antibodies were determined. RESULTS PNA-M offspring exhibited anaphylactic reactions at first exposure to peanut that were associated with peanut-specific IgG(1) levels and prevented by a platelet activation factor antagonist. In a subset experiment, PNA-M/PN offspring showed significantly reduced first-exposure peanut reactions, increased IgG(2a), and reduced mitogen-stimulated splenocyte cytokine production compared with PNA-M/none offspring. In an additional experiment, PNA-M/PN offspring showed reduction of peanut-specific IgE to active peanut sensitization. CONCLUSION We show for the first time maternal transmission of susceptibility to first-exposure peanut reactions and active peanut sensitization. Low-dose peanut exposure during pregnancy and lactation reduced this risk.

Pharmacology and immunological actions of a herbal medicine ASHMITM on allergic asthma

Allergic asthma is a chronic and progressive inflammatory disease for which there is no satisfactory treatment. Studies reported tolerability and efficacy of an anti‐asthma herbal medicine intervention (ASHMI) for asthma patients, developed from traditional Chinese medicine. To investigate the pharmacological actions of ASHMI on early‐ and late‐phase airway responses (EAR and LAR), Ovalbumin (OVA)‐sensitized mice received 6 weeks of ASHMI treatment beginning 24 h following the first intratracheal OVA challenge. EAR were determined 30 min following the fourth challenge and LAR 48 h following the last challenge. ASHMI effects on cytokine secretion, murine tracheal ring contraction and human bronchial smooth muscle cell prostaglandin (PG) production were also determined.

The Sophora flavescens flavonoid compound trifolirhizin inhibits acetylcholine induced airway smooth muscle contraction.

Asthma is a serious health problem worldwide, particularly in industrialized countries. Despite a better understanding of the pathophysiology of asthma, there are still considerable gaps in knowledge as well as a need for classes of drugs. ASHMI™ (Anti-asthma Herbal Medicine Intervention) is an aqueous extract of Ganoderma lucidum (Fr.) P. Karst (Ling Zhi), Sophora flavescens Aiton (Ku Shen) and Glycyrrhiza uralensis Fisch. ex DC (Gan Cao). It prevents allergic asthma airway hyper-reactivity in mice and inhibits acetylcholine (ACh) induced airway smooth muscle (ASM) contraction in tracheal rings from allergic asthmatic mice. The purpose of this research was to identify individual herb(s) and their active compound(s) that inhibit ASM contraction. It was found that S. flavescens, but not G. lucidum or G. uralensis aqueous extracts, inhibited ASM contraction in tracheal rings from asthmatic mice. Bioassay-guided isolation and identification of flavonoid fractions/compound(s) via methylene chloride extraction, preparative HPLC fractionation, and LC-MS and NMR spectroscopic analyses showed that trifolirhizin is an active constituent that inhibits acetylcholine mediated ASM contraction or directly relaxes pre-contracted ASM independent of β2-adrenoceptors.

The traditional Chinese herbal formula ASHMI inhibits allergic lung inflammation in antigen-sensitized and antigen-challenged aged mice.

BACKGROUND Although asthma is typically characterized as a childhood disease, it can develop later in life. Older asthmatic patients may be at increased risk for corticosteroid adverse effects. We developed a novel traditional Chinese medicine to treat asthma called antiasthma simplified herbal medicine intervention (ASHMI). Herbal products may offer safer adjunctive treatment for older asthmatic patients. OBJECTIVE To investigate the effects of ASHMI on characteristics of allergic asthma in an aged mouse model of asthma. METHODS BALB/c mice (6 weeks old [young] and 6, 12, and 18 months old [aged]) received ASHMI treatment before and during intraperitoneal ovalbumin sensitization and intratracheal challenges. The control groups were untreated, age-matched, ovalbumin-sensitized and ovalbumin-challenged mice (ovalbumin mice) and naive mice. After the final antigen challenge, airway pressure (defined as the time-integrated change in peak airway pressure) after acetylcholine provocation was measured, representing airway hyperresponsiveness, and bronchoalveolar lavage fluid, sera, lung tissues for histologic analysis, messenger RNA, and collagen were collected. RESULTS Mean time-integrated change in peak airway pressure values in 6-week-old and 6-, 12-, and 18-month-old ASHMI ovalbumin mice were significantly reduced compared with those of age-matched, nontreated ovalbumin mice. Bronchoalveolar lavage fluid eosinophil numbers were significantly lower in all ASHMI ovalbumin mice. Treatment with ASHMI of young and aged ovalbumin mice resulted in significantly decreased lung inflammation, detected via hematoxylin-eosin staining; airway mucous cell metaplasia, determined by means of periodic acid-Schiff staining; and messenger RNA copy numbers of the mucin gene MUC5AC. Levels of ovalbumin specific IgE and the T(H)2 cytokines interleukin 4 (IL-4), IL-5, and IL-13 in lung and splenocyte cultures were reduced. Interferon gamma secretion was increased. Treatment with ASHMI reduced collagen production. CONCLUSION Treatment with ASHMI reduces several features of asthma in aged antigen-sensitized and antigen-challenged mice.

Pharmacological and immunological effects of individual herbs in the Food Allergy Herbal Formula-2 (FAHF-2) on peanut allergy.

It was previously shown that a Chinese herbal formula, Food Allergy Herbal Formula 2 (FAHF‐2) composed of nine herbs, blocked peanut‐induced anaphylaxis in a murine model. The current study was designed to investigate the pharmacological actions of individual herbs comprising FAHF‐2 on peanut‐induced anaphylactic reactions in a murine model of peanut allergy and to determine if all nine herbs are necessary to prevent an anaphylactic reaction, or if a simplified formula containing fewer herbs would be equally effective. Some individual herbs reduced peanut‐induced anaphylactic symptoms but no single herb offered full protection from anaphylactic symptoms equivalent to FAHF‐2. The herbs had highly variable effects on histamine release, as well as peanut‐specific serum IgE and IgG2a levels. The herbs also had variable effects on IL‐4, IL‐5 and IFN‐γ levels. A simplified formula comprising the most efficacious tested individual herbs showed only partial efficacy and was not able to reproduce comparably the effects of FAHF‐2, suggesting that component herbs of FAHF‐2 may work synergistically to produce the curative therapeutic effects produced by the whole formula, which appears to be the best option for future clinical trials. Copyright

Efficacy, safety and immunological actions of butanol‐extracted Food Allergy Herbal Formula‐2 on peanut anaphylaxis

Cite this as: K. Srivastava, N. Yang, Y. Chen, I. Lopez‐Exposito, Y. Song, J. Goldfarb, J. Zhan, H. Sampson and X‐M. Li, Clinical & Experimental Allergy, 2011 (41) 582–591.