Detection of histamine by a new fluorescent omicron-phthalaldehyde stain

Teleost Basophils Have IgM-Dependent and Dual Ig-Independent Degranulation Systems

Recently, mammalian basophils have been highlighted as having roles in allergy and antiparasitic immunity; however, there is little information about the functions and evolutionary origin of basophils, because they are the least abundant leukocyte in most vertebrates. In this study, we characterized the teleost basophils that are abundant in the peripheral blood of fugu (Takifugu rubripes). Fugu basophils have two distinct granules: reddish-purple and dark violet ones. Teleost fish do not have IgG and IgE, but we found that fugu IgM bound on the surface of the basophils, and the cross-linked IgM induced degranulation of both types of granules. This indicates that teleost basophils can be activated in an Ab-dependent manner. Furthermore, papain induced the degranulation of the reddish-purple granules, which contain histamine, and the released granules stimulated the migration of various leukocytes. In contrast, chitin elicited the degranulation of the dark violet granules, which resulted in CD4⁺ T cell-specific migration. Thus, fugu basophils control immune responses via two distinct Ab-independent mechanisms. In addition, fugu basophils endocytosed soluble Ag and expressed MHC class II and B7-H1/DC. These findings suggested that fugu basophils can interact with T cells as APCs. Thus, the Ab-dependent basophil activation predates the emergence of IgG and IgE, and fish basophils exhibit different dynamics and features of degranulation to distinct stimuli compared with mammalian basophils. Some features of teleost basophils are more similar to those of mammalian mast cells than to those of mammalian basophils.

The Evolution of Human Basophil Biology from Neglect towards Understanding of Their Immune Functions

Being discovered long ago basophils have been neglected for more than a century. During the past decade evidence emerged that basophils share features of innate and adaptive immunity. Nowadays, basophils are best known for their striking effector role in the allergic reaction. They hence have been used for establishing new diagnostic tests and therapeutic approaches and for characterizing natural and recombinant allergens as well as hypoallergens, which display lower or diminished IgE-binding activity. However, it was a long way from discovery in 1879 until identification of their function in hypersensitivity reactions, including adverse drug reactions. Starting with a historical background, this review highlights the modern view on basophil biology.

Histamine immunocytochemistry: a new method for detection of basophils in peripheral blood

We report that basophils in peripheral blood can be stained using histamine immunocytochemistry. The staining is based on the fixation of leucocytes with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (CDI) and the subsequent incubation of these cells with antisera raised against histamine conjugated to different carrier proteins using CDI. The staining appears to be specific for basophils and stained cells can be examined using both fluorescence microscopy and flow cytometry. In addition, histamine immunocytochemistry can be combined with conventional immunocytochemistry by incubating leucocytes with antibodies to cell surface antigens prior to or following fixation of the cells with CDI. Thus, histamine immunocytochemistry may be a valuable tool in future studies of human basophils.

Histamine content and secretion in basophils and mast cells

Biochemical determinations of the histamine content and secretion from basophils and mast cells have been available for some time, and much of the complex anatomy of these cellular populations and their release reactions has been documented using the electron microscope. The ultrastructural analyses led to the description of vesicular transport between secretory granules and the plasma membrane as a mechanism for secretion from basophils and mast cells--a process termed piecemeal degranulation. Proof of concepts incorporated in a general degranulation model put forth in 1975 (DVORAK, H.F. and DVORAK, A.M.) requires high magnification imaging of a granule constituent in trafficking vesicles in the process of a stimulated release reaction in which the constituent release is monitored biochemically. Development and application of a new enzyme-affinity method to detect histamine at high magnifications in well-preserved ultrastructural samples have provided the necessary means to establish proof that appropriate secretagogues can stimulate the vesicular transport of histamine in basophils and mast cells during release reactions monitored biochemically. The background information necessary to the understanding of this result is presented here, as well as the development and verification of the diamine oxidase-gold method to image histamine in human mast cell granules as the test system. Also presented are applications using this technology to examine histamine stores and secretion in vitro, in vivo, and ex vivo in human basophils and mast cells and in mouse mast cells. Specifically examined are histamine stores developing in maturing mast cells induced to develop de novo from cultured human cord blood cells, secretagogue-stimulated release and recovery of histamine stores from isolated, purified human lung mast cells ex vivo, cytokine-stimulated degranulation of human skin mast cells and their histamine stores in vivo, piecemeal degranulation of human gut mast cells and their histamine stores in inflammatory bowel disease in vivo, piecemeal degranulation of mouse skin mast cells and their histamine stores in inflammatory eye disease in an interleukin-4 transgenic mouse model in vivo, and the stimulated secretion and recovery of histamine from human basophils ex vivo.

Histamine immunohistochemistry: a new and highly sensitive method for studying cutaneous mast cells

Mast cells have characteristic granulae containing various glucoseaminoglycans, proteases and amines (predominantly histamine). The conventional histological methods for studying mast cells are based upon acidic ortho- and metachromatic routine stains of the glucoseaminoglycans. However, the success of these procedures is dependent upon both the fixatives and the tissues used. In this study, we wanted to find out whether an immunohistochemical procedure could overcome some of these difficulties. Normal human skin was fixed in five different types of fixative and processed for indirect immunofluorescence, using an antiserum to histamine. Only one, 4% carbodiimide in 0.1 M phosphate buffer (pH 7.4), resulted in immunostaining. The quality of the staining was good, with a high signal-to-noise ratio, and was located on the mast cells. The method made it possible to visualize small structures such as a single secreted granula, the thin cytoplasmatic extension of some cells, and a previously undescribed dendritic morphology of some of the mast cells. We therefore recommend this procedure for cellular studies of mast cells when accuracy is needed.

Linear arrays of homogeneous mast cells in the dura mater of the rat

Using fluorescence histochemistry, 5-HT, histamine and heparin were colocalized in a large population of cells in the dura mater thereby identifying them as mast cells. In addition, because these cells were highly sensitive to compound 48/80 and were densely packed with granules of a consistent density, they were identified specifically as 'connective tissue' mast cells. Other types of mast cells, i.e. 'mucosal' or 'neurolipomastocytes', were not present in the rat dura mater. 5-HT immunohistochemistry was the best technique for demonstrating that there were populations of mast cells, one associated with each of the two layers of dura. Although shaped differently the type of mast cell in each layer was the same. It was observed that mast cell shape is dependent on the contiguity, density and orientation of its surrounding elements, not its type. In general, mast cells in the outer layer were aligned parallel to the middle meningeal artery and those in the inner layer were parallel to trigeminal nerve branches that coursed obliquely across the middle meningeal artery. Examination of cross-sections of dura revealed that most mast cells also were aligned at the interface between the two dural layers. The linear orientation of mast cells in two planes of each layer suggests a programmed lamellar seeding of these cells during development of the dura. This study also demonstrated that the majority of dural mast cells were more closely related to other connective tissue elements than to blood vessels and nerves. These results (1) are compatible with the suggestion that dural mast cells play a non-obligatory role in the neuroinflammatory response, (2) leave open to question the role of the dural mast cell in headache or the regulation of blood flow, and (3) support evidence that dural mast cells play an important role in connective tissue related functions, e.g. development, inflammatory response to injury and wound repair.

Histamine-containing neurons in the rat hypothalamus

A specific antiserum against histamine was produced in rabbits, and an immunohistochemical study of histamine-containing cells was carried out in rat brain. The antiserum bound histamine in a standard radioimmunoassay and stained mast cells located in various rat and guinea pig tissues. Enterochromaffin-like cells in the stomach and neurons in the posterior hypothalamic area could be detected with this antiserum. The staining was highly specific and was not abolished by preabsorption with histidine, histidine-containing peptides, serotonin, or catecholamines, whereas preabsorption with histamine completely abolished the staining. Immunoglobulins of this antiserum purified by affinity chromatography stained the same cells as did the crude antiserum, whereas the serum fraction, which was not absorbed by histamine-affinity ligand, failed to stain any neuron. Histamine-immunoreactive neuronal cell bodies were found only in the hypothalamic and premammillary areas of colchicine-treated rats. The largest group of cells was seen in the caudal magnocellular nucleus and medially on the dorsal and ventral aspects of the ventral premammillary nucleus. Immunoreactive nerve fibers, but no cell bodies, were detected in other parts of the brain. Histamine-immunoreactive mast cells were found in the median eminence and pituitary gland. The results suggest that histamine-containing neurons are located only in a small area of the posterior hypothalamus, and these cells are probably the source of ascending and descending fibers detected in other brain areas.

In vitro production of granular T cells and mast cells by use of different conditioned media. Ultrastructural and functional analysis

Normal mouse spleen cells were cultured in different conditioned media (CM). Mixed lymphocyte culture supernatant (MLC SN) was shown to promote the proliferation of cytotoxic, Thy-1+, Lyt-1+, Lyt-2+, asialo-GM-1+, weakly adherent cells with numerous vacuoles and lysosome-like cytoplasmic granules. In contrast, the Con A SN induced the proliferation of non-cytotoxic, Thy-1-, Lyt-1-, Lyt-2-, asialo-GM-1-, non-adherent cells with numerous cytoplasmic granules. The ultrastructural morphology of these cells and the cytochemical characteristics of their granules enable us to identify them as mast cells. The different effects of both CM could be related to their T-cell growth factor (TCGF) content. When the amount of TCGF of these two CM was determined (by assaying growth-stimulating activity for T-cell colonies), it appeared that the MLC SN contained larger amounts of TCGF than the Con A SN used in these experiments.

Ante-mortem injury or post-mortem?--Diagnosis using histamine as a marker

A relatively simple method for differentiating ante-mortem from post-mortem injuries is described. It involves the demonstration of an increase in free histamine at sites of injury by fluorescent microscopy on the basis that release of free histamine is a very early vital reaction to injury.

The persisting (P) cell: histamine content, regulation by a T cell-derived factor, origin from a bone marrow precursor, and relationship to mast cells

Histamine was detected at levels of 100 ng/10(6) cells in the metachromatic granules of the persisting (P) cell, which appears in cultures of murine lymphoid or bone marrow cells and is capable of long-term growth in vitro in the presence of a T cell-derived growth factor. This factor, which we termed P-cell stimulating factor, was distinct from t-cell growth factor and had an apparent molecular weight of 25,000-30,000. P cells did not originate from Thy.1-positive cells nor was the thymus necessary for the development of their precursors. Moreover, P cells grew directly from colonies generated in agar cultures of bone marrow cells, the nature of the colonies indicating that P cells shared a common precursor with hemopoietic cells. Mutant Wf/Wf mice, although deficient in certain mast cells, possessed P-cell precursors. It is hypothesized that P cells are related to a specialized subset of mast cells, derived from a bone marrow progenitor but regulated by activated T cells.

Characterization of intensely fluorescent cells in the liver of the rat. i. Histochemistry and 48/80-induced degranulation

The nature of the intensely fluorescent cells (IFC) in the livers of male Sprague-Dawley rats was evaluated using histochemical and pharmacological techniques. The number and distribution of IFC in portal areas were quantified using some of these techniques. Cells which were metachromatic as well as fluorescent for serotonin, histamine, and heparin were observed in the connective tissue of the portal space, hilus, and capsule of the liver. Cells with the characteristics of chromaffin, enterochromaffin, or enterochromaffin-like cells were not seen in these locations. Intravenous administration of compound 48/80 a known mast cell degranulator, caused a significant decrease in the number of fluorescent and metachromatic cells in the portal areas of the liver. However, no significant difference was found in the number of cells counted in either the 48/80 or control groups when comparing the data from several histochemical methods. These results provided evidence that: (1) IFC demonstrate both fluorescence and metachromasia and, therefore, are mast cells, (2) compound 48/80 causes a comparable decrease in the number of serotonin and histamine fluorescent as well as metachromatic cells, indicating concomitant rather than differential release of serotonin, histamine, heparin, and/or other metachromatic substances, and (3) each of the three histochemical methods appears of equivalent sensitivity when used to study the effect of various factors (i.e., 48/80) on the release of endogenous substances from IFC. The results of this study indicate that the effects of 48/80 in vivo might be mediated through the release of various vasoactive substances from these IFC (mast cells).

An immunocytochemical method for histamine detection

An anti-histaminic immune serum, prepared in New Zealand male rabbits by immunization with a chemospecific antigen (diazotized para-amino-benzoyl-azohistamine) was labeled with fluorescein isothiocyanate for the purpose of histamine detection or was employed for demonstration of histamine using fluorescein-labeled protein A. The IgG fraction of the hyperimmune serum was isolated, purified, and tested for specificity by binding to 3H-histamine or to histamine-containing or histamine-treated cells. Histological preparations used for detection of histamine should be fixed preferably in Carnoy solution. The procedure can also be employed for ultra-histochemical detection of histamine, using ferritin-conjugated antibody or the peroxidase technique.

Localization of histamine and histamine H2-receptor antagonists in the gastric mucosa

Histamine stimulates acid secretion by the parietal cell and this secretion is inhibited by the histamine H2-receptor antagonists. Whole body autoradiography showed that radioactivity from 14C-histamine was localized in the artery walls of the stomach and in the muscularis mucosae, but that the level in the fundic mucosa was the same as the blood. When the H2-receptor antagonists burimamide, metiamide and cimetidine were labelled with 35S, 14C or 3H and dosed to rats, whole body autoradiography showed that the stomach was predominantly labelled in the glandular mucosa from 5 to 120 min after administration. Microautoradiography in the rat and dog after intravenous injection of [3H]metiamide or [3H]cimetidine demonstrated an uptake of tritium in the parietal cell cytoplasm that was 3- to 4-times greater than that found in adjacent peptic cells or areas of muscularis mucosa. The preferential labelling persisted at a low level up to 6h after injection in the rat. The localization of radioactivity from the H2-antagonists in the parietal cell cytoplasm correlates well with their pharmacological activity in preventing acid secretion from this cell.

Cytochemical detection of histamine in the human granulopoietic series of healthy subjects and of patients affected by chronic myeloid leukaemia. A spectrophotofluorimetric test for checking OPT-induced fluorescence in isolated cells

Cellular histamine in blood and bone marrow has been identified histochemically using an o-phthaldialdehyde fluorescence reaction. The specificity of the reaction was tested by a spectrofluorometric analysis of cell extracts. In normal blood, the basophils emit a bright yellow fluorescence, whereas neutrophils, eosinophils and platelets react less consistently and when they do, they give off a less intense yellow or blue emission. In normal marrow, basophils react strongly whereas the metamyelocytes and later granular cells show only a weak yellow or blue fluorescence. In chronic myeloid leukaemia, cells of the granular series emit a strong yellow fluorescence at all stages of development, although still less intense than the basophils. During remission, the fluorescence pattern of cells from leukaemic subjects reverts to that of normal cells.

Serotonin containing and histamine containing cells in human stomach. Identification of these cells by fluorescent microscope and electron microscope

Paraformaldehyde (PF) treatment of epithelial cells of human stomach revealed intense yellow fluorescent granules within the cells. These granules were identified as serotonin on microspectrofluorometry. Serotonin containing cells were also identified as enterochromaffin cells (EC cells) under electron microscope and by the histochemical analysis. O-phthalaldehyde treatment (OPT) of epithelial cells in human stomach demonstrated whitish blue intracellular granules under fluorescence microscope. The cells containing these granules were identified as histamine containing cells on microspectrofluorometry, because of accordance in excitation and emission spectra with authentic histamine. Histamine-containing cells were considered to be identical to the mast cells, because of metachromatic property on toluidine blue staining and of close structural similarities under electron microscope.

[Biogenic amines in endocrine cells producing polypeptide hormones. The APUD-cells (Pearse) (author's transl)]

APUD-cells (A = Amine, P = Pprecursor, U = Uptake, D = Decarboxylation) are endocrine cells with numerous common characteristics: 1. They produce polypeptide hormones of low molecular weight. 2. They possess specific 1-amino acid decarboxylases to synthesize catecholamines and/or 5-hydroxytryptamine from precursors. 3. A part of the APUD-cell family primarily accumulates biogenic amines within their cytoplasm. 4. All APUD-cells are rich in specific secretory granules that are the morphological substrate for most of their common features.--Enzyme histochemically the APUD-cells represent a rather heterogenous population. The capacity to take up biogenic amines from the blood is confined to a smaller numer of APUD-cells. The concept of the APUD-cells representing a peripheral neurosecretory system (Pearse und Polak, 1971) appears to be premature. It is probable that in several APUD-cells the accumulation of biogenic amines only constitutes a phenomenon without any physiological relevance which, notwithstanding, could explain pathological reactions of APUD-cells.