Modulation of allergen and anti-igE induced human basophil activation by serial histamine dilutions

Basophil models of homeopathy: a sceptical view

This paper examines the activation and inhibition of activation of human basophils. After a brief description of human basophils, different methods to determine basophil activation are discussed with a special emphasis on the use of flow cytometric methods, as these circumvent the potential problems of assays based on the loss of colour by activated basophils. The activation of human basophils by ultra-high dilutions of anti-IgE is discussed. The majority of the paper describes the inhibition of basophil activation by ultra-high dilutions of histamine. The results from published papers are described and discussed. After over 20 years research trying to find out if high dilutions of histamine have a negative feedback effect on the activation of basophils by anti-IgE, what do we know? The methods are poorly standardized between laboratories - although the same is true for conventional studies. Certainly there appears to be some evidence for an effect - albeit small in some cases - with the high dilutions in several different laboratories using the flow cytometric methodologies. After standardization of a number of parameters, it is recommended that a multi-centre trial be performed to hopefully put an end to this "never-ending story".

Inhibition of basophil activation by histamine: a sensitive and reproducible model for the study of the biological activity of high dilutions

BACKGROUND

At the beginning of this series of experiments we were looking for a model based on the use of purified commercially available compounds based on a fully described and accepted pharmacological model to study of the biological effect of high dilutions. Negative feedback induced by histamine, a major pro-inflammatory mediator, on basophils and mast cells activation via an H2 receptor me these criteria. The simplest way of measuring basophil activation in the early 1980's was the human basophil activation test (HBDT).

OBJECTIVES

Our major goal was first to study the biological effect of centesimal histamine dilutions beyond the Avogadro limit, on the staining properties of human basophils activated by an allergen extract initially house dust mite, then an anti-IgE and N-formyl-Met-Leu-Phe (fMLP). Technical development over the 25 years of our work led us to replace the manual basophil counting by flow cytometry. The main advantages were automation and observer independence. Using this latter protocol our aim was to confirm the existence of this phenomenon and to check its specificity by testing, under the same conditions, inactive analogues of histamine and histamine antagonists. More recently, we developed an animal model (mouse basophils) to study the effect of histamine on histamine release.

METHODS AND RESULTS

For the HBDT model basophils were obtained by sedimentation of human blood taken on EDTA and stained with Alcian blue. Results were expressed in percentage activation. Histamine dilutions tested were freshly prepared in the lab by successive centesimal dilutions and vortexing. Water controls were prepared in the same way. For the flow cytometric protocol basophils were first labeled by an anti-IgE FITC (basophil marker) and an anti-CD63 (basophil activation marker). Results were expressed in percentage of CD63 positive basophils. Another flow cytometric protocol has been developed more recently, based on basophil labeling by anti-IgE FITC (fluorescein isothiocyanate) and anti-CD203 PE (another human basophil activation marker). Results were expressed in mean fluorescence intensity of the CD203c positive population (MFI-CD203c) and an activation index calculated by an algorithm. For the mouse basophil model, histamine was measured spectrofluorimetrically. The main results obtained over 28 years of work was the demonstration of a reproducible inhibition of human basophil activation by high dilutions of histamine, the effect peaks in the range of 15-17CH. The effect was not significant when histamine was replaced by histidine (a histamine precursor) or cimetidine (histamine H2 receptor antagonist) was added to the incubation medium. These results were confirmed by flow cytometry. Using the latter technique, we also showed that 4-Methyl histamine (H2 agonist) induced a similar effect, in contrast to 1-Methyl histamine, an inactive histamine metabolite. Using the mouse model, we showed that histamine high dilutions, in the same range of dilutions, inhibited histamine release.

CONCLUSIONS

Successively, using different models to study of human and murine basophil activation, we demonstrated that high dilutions of histamine, in the range of 15-17CH induce a reproducible biological effect. This phenomenon has been confirmed by a multi-center study using the HBDT model and by at least three independent laboratories by flow cytometry. The specificity of the observed effect was confirmed, versus the water controls at the same dilution level by the absence of biological activity of inactive compounds such as histidine and 1-Methyl histamine and by the reversibility of this effect in the presence of a histamine receptor H2 antagonist.

The in vitro evidence for an effect of high homeopathic potencies—A systematic review of the literature

OBJECTIVE

Systematic assessment of the in vitro research on high potency effects.

METHOD

Publications of experiments were collected through databases, experts, previous reviews, citation tracking.

INCLUSION CRITERIA

stepwise agitated dilutions <10(-23); cells or molecules from human or animal. Experiments were assessed with the modified SAPEH score.

RESULTS

From 75 publications, 67 experiments (1/3 of them replications) were evaluated. Nearly 3/4 of them found a high potency effect, and 2/3 of those 18 that scored 6 points or more and controlled contamination. Nearly 3/4 of all replications were positive. Design and experimental models of the reviewed experiments were inhomogenous, most were performed on basophiles.

CONCLUSIONS

Even experiments with a high methodological standard could demonstrate an effect of high potencies. No positive result was stable enough to be reproduced by all investigators. A general adoption of succussed controls, randomization and blinding would strengthen the evidence of future experiments.

Priorities and methods for developing the evidence profile of homeopathy Recommendations of the ECH General Assembly and XVIII Symposium of GIRI

To achieve scientific acceptance, homeopathy must investigate several questions: 1. The activity of very highly diluted preparations. The consensus of the meeting was that there is clear evidence of this. 2. The content of very highly diluted homeopathic preparations. More research is needed but evidence exists that a specific signal is present in homeopathic preparations. 3. A theoretical framework in which the effects of homeopathic diluted preparations can be explained. The 'Body Information Theory' is such a theory. 4. The clinical effectiveness of homeopathy. Because they avoid the placebo effect, animal studies are a priority. For human trials using Quality of Life questionnaires, studies on the activity, content and theoretical basis of homeopathic preparations were reviewed approximately 70% of cases; more in children showed improvement. Homeopathy reduced costs and allowed a better improvement in work-days lost compared with conventional practice. Randomised controlled trials (RCTs) implicitly test the placebo hypothesis; RCTs have been performed and meta-analyses conclude that there is clear evidence of efficacy which cannot be attributed to placebo effect. Priorities depend on the audience. More research is needed especially regarding the content of homeopathic preparations and the transmission of information. Theoretical issues are also important to avoid incorrect design of research protocols. More effort should be dedicated to veterinary research. Clinical effects analysis in humans remains important. Many other questions should be prioritised, such as the potential of homeopathy to avoid invasive procedures in children and the long-term effects of homeopathy in preventing chronic complications.

Towards understanding molecular mechanisms of action of homeopathic drugs: an overview

The homeopathic mode of treatment often encourages use of drugs at such ultra-low doses and high dilutions that even the physical existence of a single molecule of the original drug substance becomes theoretically impossible. But homeopathy has sustained for over two hundred years despite periodical challenges thrown by scientists and non-believers regarding its scientificity. There has been a spurt of research activities on homeopathy in recent years, at clinical, physical, chemical, biological and medical levels with acceptable scientific norms and approach. While clinical effects of some homeopathic drugs could be convincingly shown, one of the greatest objections to this science lies in its inability to explain the mechanism of action of the microdoses based on scientific experimentations and proofs. Though many aspects of the mechanism of action still remain unclear, serious efforts have now been made to understand the molecular mechanism(s) of biological responses to the potentized form of homeopathic drugs. In this communication, an overview of some interesting scientific works on homeopathy has been presented with due emphasis on the state of information presently available on several aspects of the molecular mechanism of action of the potentized homeopathic drugs.

Influence of the diluent on the effect of highly diluted histamine on basophil activation

BACKGROUND

In modern pharmaceutical practice, it is common to use purified ethanol and purified water for the preparation of homeopathic dilutions. Hahnemann in 1827 recommended good brandy as a diluent. Brandy contains a lot of accompanying substances in addition to ethanol.

PURPOSE OF THE STUDY

The research question was whether different diluents influence the effectiveness of high dilutions, especially above Avogadro's number. We compared two dilution media to investigate the diluent's influence. Within the limitations of the test-system, the dilution media were as similar to good brandy as possible and like purified ethanol. Dilutions of histamine were prepared with both media. As test-system, we used modified basophil activation in an in vitro cell system. Basophils are activated by anti-immunoglobulin E (anti-IgE). The activation of basophils is inhibited by prior incubation with histamine. The reduction in activation was measured with different dilutions of histamine. The test system used a 3-colour flow cytometric method. The interleukin-3 (IL-3) receptor CD123 was used to identify basophils in the leukocyte mixture. The CD63 surface marker was used for quantification of activated basophils.

RESULTS

With higher concentrations of histamine, we observed inhibition on optimally anti-IgE-stimulated basophil activation with a clear concentration dependency. With low concentrations of histamine (up to 10(-31)), we also observed inhibition of IgE-mediated basophil activation. Differences were observed between the dilution media.

CONCLUSION

The preliminary results support the hypothesis that the dilution medium may influence the effects of high dilutions. This could be of importance for homeopathic pharmaceutical practice as well as for ultra-high dilution experiments. The refined basophil test system proved to be highly sensitive and reliable. Further studies are needed.