Effect of normal and immune IgG, IgM and IgA on the intestinal microflora of mice with experimental dysbacteriosis

Human IgG, IgM and IgA produce a pronounced protective effect, preventing enterobacteria from penetration into the mucous membrane of the proximal section of the small intestine of mice in antibiotic-induced dysbacteriosis. Normal mouse IgG and IgM, in contrast to IgA, are effective against mucosal enterobacteria of the small intestine. Immune mouse IgG, IgM and IgA show greater activity in protecting the mucous membrane than normal immunoglobulins of these classes.     

Age-related changes in the morphology and the distribution of IgA and IgG in the pharyngeal tonsils of yaks (Bos grunniens)

To evaluate age-related changes in the morphology as well as the expression and localization of IgA and IgG in yak pharyngeal tonsils, 20 healthy yaks were divided into four age groups [newborn (1–7 days old), juvenile (5–7 months old), adult (3–6 years old) and old (7–10 years old)]. Morphologic characteristics were observed by histological techniques. The expression and localization of IgA and IgG in pharyngeal tonsils were detected by enzyme linked immunosorbent assay (ELISA) and immunohistochemistry, respectively. The results showed that the epithelium of the pharyngeal tonsils included nonreticular epithelium with an intact basement membrane and reticular epithelium with a discontinuous basement membrane and nonepithelial cell infiltration. In newborn yaks, only primary lymphoid follicles were observed in pharyngeal tonsils. In other age groups, both primary and secondary lymphoid follicles were observed, but some of the lymphoid follicles in the old yaks were degenerated. The number of lymphoid follicles increased from the newborn to the adult group and peaked in the adult group, but the number decreased in the old group. In addition, the age-related trends of IgA and IgG protein expression were similar to those of the number of lymphoid follicles. The concentration of IgG was significantly higher than that of IgA in all age groups. Both IgA and IgG antibody secreting cells (ASCs) were distributed in the subepithelial region of the nonreticular epithelium, the reticular epithelium, the lymphoid follicles, the interfollicular areas and in between the salivary glands. The densities of IgA and IgG ASCs in pharyngeal tonsils were similar to the expression trend of both proteins in each age group. The results indicate that the morphology and amount of lymphoid follicles in yak pharyngeal tonsils vary with age. Pharyngeal tonsils produce more IgG than IgA, indicating that IgG could be significant component of mucosal immune responses in yaks.     

Increased migration of IgA lymphocytes to VIP nerve fibers after DSS-induced colitis

Immunoglobulin-positive lymphocytes are present close to vasoactive intestinal polypeptide-positive (VIP(+)) nerve fibers in the lamina propria of the intestinal tract, and have an important role in mucosal defense. The number of immunoglobulin A-positive (IgA(+)) cells close to the epithelial basement membrane and nerve fibers is increased by the administration of lipopolysaccharides, which induce IgA secretion into the intestinal lumen. The relationship between immunoglobulin-positive lymphocytes and the VIP(+) nerve fibers during inflammation, such as in inflammatory bowel disease, however, is not well known. The morphological relationship between immunoglobulin-positive cells and the basement membrane or the VIP(+) nerve fibers in the colon was examined using double immunofluorescent labeling in an inflammatory bowel disease mouse model created by oral administration of dextran sodium sulfate (DSS). DSS administration induced goblet cell loss, crypt loss, intestinal epithelium deformation and infiltration of inflammatory cells in the mucosa. In the colon, the number and percentage of IgA(+) lymphocytes close to the basement membrane and the VIP(+) nerve fibers in the lamina propria increased after DSS administration, in parallel with the pathologic progress in the inflamed tissue. On the other hand, the percentage of immunoglobulin G-positive (IgG(+)) lymphocytes close to the basement membrane and the VIP(+) nerve fibers decreased, although the total number of IgG(+) lymphocytes in the lamina propria increased. We suggest that the immunoglobulin-producing lymphocytes and enteric nerve fibers in the colon normally have a close morphological relationship, and that this relationship is reinforced in a cell-specific manner during inflammation.     

Structure and histochemical characteristics of the mucosa of the Vater's ampulla in man (according to materials of aimed biopsies)]

Examination of 52 aimed duodenal biopsies has revealed that there are several variants of the structure of the Vater's papilla mucous membrane. In a number of cases it is identicalto the mucous membrane of the duodenum. In 20 cases the Vater's papilla was covered with mucoid epithelium which was histochemically similar to the epithelium lining the stomach, bile ducts and the gallbladder. The "intermedial" forms found in these cases appearedto be capable to change into mucoid or edging epithelium. The mucous cells occasionally found in the Vater's papilla epithelium might be a variation of goblet cells. It seems that they are secreting by holocrine type.     

The localization of IgA and IgE globulins in the palatinal tonsils,nasal mucous membrane and nasal polypi

Using the immunofluorescence method, the localization of IgA and IgE globulins was studied in tonsillar tissue, nasal and pharyngeal mucous membranes and nasal polypi of patients hospitalised at the Clinic of Otorhinolaryngology. No difference in either localization and number of cells containing blood and/or secretory IgA globulin could be found in individual patients. Great amounts of IgE globulin were found in nasal mucous membrane and nasal polypi in subepithelial plasma cells even in patients without demonstrable allergy.     

Quantitative analyses of the relationship between C3 consumption, C3b capture, and immune adherence of complement-fixing antibody/DNA immune complexes

We have studied the turnover of the third component of C (C3) and capture of the major cleavage fragment of C3 produced during C activation (C3b) that occurs when soluble antibody/DNA immune complexes (IC) active C. We used the Amersham RIA kit for the minor cleavage fragment of C3 produced during C activation (C3a), and a new assay utilizing mAb to C3b to measure the fraction of active C3 in a C source after the IC activate C. These mAb, along with a mAb to human IgG, allowed us to measure IC stoichiometries. The efficiency of C3 turnover by the IC is quite high, and under conditions of Ab excess, the maximum number of IgG bound per dsDNA corresponds to 1 IgG/20 to 30 base pairs. The maximum number of C3b found in the IC corresponds to less than 1 C3b/IgG, and the vast majority of the captured C3b is bound to the IgG, and not to the DNA. We identified several IC that consumed large amounts of C3, and captured large amounts of C3b, but did not bind to human E via C3b receptors (C receptor type 1). This finding suggests that the ability of IC to bind to human E depends upon the number and distribution of captured C3b molecules and the conformation and size of the DNA Ag, which reflects the need for multivalent binding between several properly arrayed C3b and a "cluster" of C receptor type 1 on the human E membrane. IC that activate C3 but do not bind to E would presumably "escape" the E IC clearance mechanism, but could deposit in susceptible organs and tissues and play a role in the pathogenesis of SLE because of their potential to generate the inflammatory products of C activation.     

Effect of a live enteral dysentery vaccine from spontaneous Flexner mutant 2a 516m on the immunoglobulin-producing cell count in the large intestine mucosa in dysentery

The influence of vaccinal therapy with live oral dysentery vaccine prepared from S. flexneri 2a 516M on the content of immunoglobulin-producing cells in the mucous membrane of the large intestine was studied. A considerable increase in the number of IgA- and IgM-synthetizing cells was shown to occur in the course of the infectious process in acute dysentery. In chronic dysentery the content of IgA- and IgM-synthetizing cells in patients was considerably lower than in a smooth course of acute dysentery. The use of the vaccine for the therapy of patients with chronic and especially acute dysentery resulted in a considerable rise in the number of plasma cells synthetizing IgA, IgM and IgG.     

A comparison of the dynamics of changes in large intestinal mucosa of acute dysentery patients with detection of a specific antigen in urine

The relationship between the elimination of shigellae from the body with urine and the dynamics of morphological changes in the mucous membrane of the large intestine of acute dysentery patients at the early convalescence period has been studied. The persistence of Shigella antigen in acute dysentery patients and its elimination with urine is, as a rule, accompanied by local immune cell reaction in the mucous membrane of the large intestine. The antigen circulating in the body is a factor contributing to the inflammatory process in the intestine, the amount of the eliminated antigen being higher in pronounced inflammations of the intestinal mucosa than in residual inflammatory phenomena. A group of patients (3 persons) releasing Shigella O-antigen with urine and having the inflammatory process in the large intestine, but showing no signs of local immune reaction in the lymphoid tissue of the large intestine, has been found. The reactivity of the lymphoid tissue of the intestine in such patients is a risk factor contributing to the development of prolonged dysentery or chronic postdysenteric colitis.     

Ultrastructural organization of the surface epithelium of gastric mucosa in vitamin A deficiency

Under conditions of experimental A-avitaminosis in cells of superficial epithelium of the chicken stomach mucous membrane certain ultrastructural changes of cytoplasmic membranes takes place. Amount of transport vesicles decreases, regeneration of membranes in the Golgi complex cisterns, secretory vesicles and apical part of the external cellular membrane with development of apical erosions is disturbed. The problem on influence of the changes mentioned to the process of mucus formation, in particular to protein glycosylation in the Golgi complex is discussed. Insufficient vitamin A amount, getting into the organism results in a decreased resistivity of the stomach mucous membrane as a consequence of disturbances in processes of mucus formation and in safety of the apical part of the external cellular membrane of the superficial epithelium.     

Morphological aspect of voice disturbances of aged persons coexisting hypopharynx cancer

The voice quality in prebysphonia is conditioned by morphological changes in the vocal folds mucosa. The studies including light microscopy and transmission electron microscopy (TEM) revealed changes within the basal membrane epithelium and the stroma of the vocal folds mucosa. Age-related changes in thickness of the epithelium and direction of the basal membrane, increased number of collagenous fibres (C) and fibroblasts and chronic inflammatory process in the stroma were found. Vacuolated and keratinised epithelial cells, enlarged extracellular spaces and numerous blood vessels confirm the edematous form of prebysphonia. Thinned epithelium with signs of hyalinization, inflammatory infiltrations in the stroma with numerous collagenous fibres and small number of blood vessels indicate atrophy of the vocal folds mucosa. Edematous and atrophic changes in the vocal folds mucosa are most frequently reported form of prebysphonia.     

Dynamics of Shigella interaction with the epithelium in the infection process

The study of the adhesion of Shigella flexneri to intestinal mucosal explants from human postabortion fetuses, used as an experimental model, has revealed that the process of interaction between the infective agent and the epithelium develops in accordance with Langmuir's equation of the adsorption isotherm. The specific biological feature of the adhesive interaction between bacteria and the mucous membrane is the fact that the effective adhesion of microbes is possible only in case of their high concentration on the surface of the mucous membrane. In case of their low concentration in the parietal layer no microbial adhesion is observed, whereas epithelial villi infected with shigellae and fixed to the mucous membrane of the explant produce a high parietal concentration of the infective agents, which leads to the increase of adhesion by more than two orders.     

Microcirculatory bed of the epithelial layer of human esophageal mucous membrane in postnatal ontogenesis

The analysis of histological changes in epithelium layer of mucous membrane and its microcirculatory channel of human oesophagus show that development and formation of epithelium and its capillary channel are interwoven processes. Dynamics of their morphological changes strictly correspond to a definite age stage of organ individual development. Changing each other determined four types of capillaries of mucous membrane epithelium layer and determined the degree of its functional development.     

Induction of granulocyte histaminase release by particle-bound complement C3 cleavage products (C3b, C3bi) and IgG

The interaction of opsonized particles with human granulocytes promotes a number of important biologic functions, including phagocytosis, superoxide generation, and release of a variety of enzymes, including histaminase. We have previously determined that histaminase release occurs via a C3-dependent process. Although fluid-phase C3b dimers can mediate release, the relative effects of particle-bound C3b and C3bi and of IgG have not been examined. In this report we demonstrate that particle-bound C3 deposited on activators of the alternative C pathway effected histaminase release in the absence of IgG. Particle-bound C3bi and C3b were both effective as mediators of histaminase release. The extent of release varied as a function of the activating surface on which C3 was deposited (zymosan C3b was considerably more potent than C3b bound to rabbit erythrocytes, which was slightly more potent than C3b bound to neuraminidase-treated sheep erythrocytes). In contrast, C3b or C3bi deposited on nonactivating surfaces (such as sheep erythrocytes) at inputs of up to 2,000,000 molecules per granulocyte failed to induce histaminase release unless IgG was also present. The ability of C3b bound to particles that serve as activators of the alternative pathway to induce histaminase release is apparently not the result of decreased susceptibility of C3b to proteolysis or to an increased binding affinity to the C3b receptor, but may relate to the interaction of other surface structures on activating particles with the PMN membrane.     

Functional and morphological characteristics of the digestive reaction of gastric mucosa

Morphological state of connective tissue (stromal) cells of the stomach mucous membrane has been studied in healthy persons, having a habitual regime of feeding. During digestive period in the stomach mucous membrane, certain changes develop, which are considered as a digestive reaction. Three stages of the digestive reaction, having strict morphological signs are determined, their connections being stated by means of morphometry and mathematical analysis. I stage (preparatory) is characterized with a moderate vascular reaction, degranulation of mast cells under the superficial++ epithelium of the mucous membrane, with a moderate neutrophilic leukopedesis and a moderate lymphocytic infiltration; II stage (developed) is distinguished as a definitely demonstrated reaction of the microcirculatory bed, intensive degranulation of mast cells at all levels of the mucous membrane, massive discharge of neutrophilic granulocytes and lymphocytes into stroma; III stage (restorative) is characterized with a predominance of fibroblasts and fibrocytes, with reparation of mast cells, with decreasing saturation of stroma with neutrophilic granulocytes, lymphocytes, an increased number of eosinophilic granulocytes takes place. The data obtained widen our knowledge on functional morphology of the stomach mucous membrane, normal and at gastroduodenal pathology.     

Class IgG,IgM and IgA antibodies againstStaphylococcus aureus antigens in human serum and saliva

Using the ELISA method antibodies against the sonicate, teichoic acid (TA) and exoproducts ofStaphylococcus aureus were determined in sera and saliva of healthy individuals. Main serum antibodies against all the antigens used were shown to be class IgG antibodies. However, antigens of the sonicate stimulated significantly even the systemic IgA response. In the saliva class IgA antibodies predominated, but IgG antibody levels against TA and exoproducts approached the level of IgA antibodies. Levels of IgM antibodies against all antigens tested were low in both the serum and saliva which corresponds with the anamnestic type of response. On the basis of these results one may assume that not only IgG, but also IgA antibodies are important in the systemic immunity against staphylococcal infection and in the immunity of mucous membranes; besides IgA, even class IgG antibodies play an important role.     

The effect of stress on the stomach of the European eel, Anguilla anguilla L.

The gastrointestinal tract is a system that is very sensitive to stress-like conditions in mammals. Fish display physiological reactions to stress that are fundamentally similar to those of the'General Adaptation Syndrome' in higher vertebrates. An investigation was therefore undertaken to determine if morphological changes equivalent to those affecting the stomachs of mammals also occur in fish under stress.
Conflict for social dominance served as the stressor. The unavoidable confrontation with a dominant fish in a tank proved to produce great stress for the subordinate eel. This was demonstrated by a number of physiological and haematological parameters.
Stressed eels have shrunken stomachs, the consistency of which is translucent and soft. The mucous membrane folds flatten or disappear. The mucous epithelium atrophies and during this process numerous residual bodies appear. The cell-to-cell contact loosens. The gastric glands degenerate developing large intracellular cavities, vacuolated ER and swollen mitochondria. The connective tissue proliferates replacing the necrotic glands. The submucosal vessels contract, thereby disturbing the circulation.
The consequences of the gastric atrophy (increased self-digestion, reduction of the immunological barrier, interference with protein digestion, endocrine function, etc.) are discussed.     

Epithelial ultrastructure and the distribution of an estradiol sensitive antigen in the vagina of adult mice

Summary The distribution of an antigenic material specific for the cervicovaginal epithelium (CVA) was studied in the vaginal epithelium of the adult mouse with immunofluorescence and immunoferritin techniques. The antigen localization has been correlated to the fine structure of the vaginal epithelium in various states of functional activity. The antigen distribution in adult ovariectomized mice and in ovariectomized mice treated with estradiol was compared with that in normal cycling mice. CVA was found to be associated with the exterior of the cell membrane of vaginal epithelium cells, being part of the glycocalyx.Two cell types, mucous or keratinized, are derived from the germinative cell layer of the vaginal epithelium, depending on the hormonal environment. Mucous cells with morphological features that characterize cells about to cornify have been demonstrated. Fluorescence as well as ferritin particles, indicating the presence of antigen-antibody complexes, were seen within the mucous droplets of the mucous cells. The CVA production is apparently connected with vaginal mucus formation. The CVA distribution in the adult vaginal epithelium is discussed in relation to the distribution demonstrated earlier in the cervicovaginal epithelium of neonatal mice.This investigation was supported by grants from the Norwegian Cancer Society (Landsforeningen mot Kreft) and the Norwegian Research Council.     

Regulation of mucous cell metaplasia in bronchial asthma

Mucous cell metaplasia (MCM), defined by the appearance of mucous cells in airways where mucous cells were not present, is a consistent pathologic characteristic in the peripheral airways of bronchial asthma. Under mild inflammatory conditions MCM occurs as a result of pre-existing airway epithelial cells (AECs) starting to express mucin genes and differentiating into mucous cells. Under extensive inflammatory responses, AECs proliferate, and the development of MCM involves the differentiation of pre-existing and proliferating cells into mucous cells. Epithelial cell numbers per mm basal lamina are increased by approximately 30%. IL-13 is the central cytokine that is responsible for MCM in asthma through GABA-R- and STAT6-mediated mechanisms involving the calcium-activated chloride channel CLCA. IL-13 is also responsible for the proliferation of AECs by causing cells to produce TGFalpha that acts on the epidermal growth factor (EGF) receptor. Normally, resolution of MCM involves two distinct mechanisms. 1) Some of the metaplastic mucous cells stop the synthesis of mucus and dedifferentiate into Clara or serous cells to reconstitute the epithelium. 2) When proliferation of epithelial cells had occurred, approximately 30% of metaplastic cells are eliminated during the resolution process. Thus, a safe approach to reducing IL-13-induced MCM would involve blocking mucous synthesis and storage, blocking secretion of stored mucus, and eliminating hyperplastic mucous cells. Understanding the molecular mechanisms of each of these processes is necessary for developing effective therapies for reducing mucous hypersecretion in asthma and leading to a repaired epithelium.     

The role of Candida kefyr (C. pseudotropicalis) in reproductive tract infections]

Frequency of appearance of C. kefyr strains, their diagnosis, susceptibility to drugs and importance in pathogenesis of reproductive tract mycoses were investigated. The investigated material consisted of 2717 strains, and there were 67 strains of C. kefyr isolated from vaginal mucous membrane. C. kefyr strains constituted 2.5% of total number of 2717 isolated strains and 8.2% within fungi other than C. albicans species. Vaginal mycosis caused by C. kefyr occurs in presence of Lactobacillus sp. and correct values of pH in vaginal contents, however changing leukocyte number was observed. Clinical symptoms and complaints regarding reproductive tract were present in 47.8% of patients with C. kefyr infections. Investigating susceptibility to antimycotic drugs, regardless of appointed method, low susceptibility of C. kefyr strains to amphotericin B was noted (79% resistant strains). Strain of C. kefyr were sensitive to all remaining drugs.