MORPHOLOGICAL CHARACTERISTICS OF GUINEA PIGS BRONCHUS ASSOCIATED LYMPHOID TISSUE IN THE DYNAMICS OF EXPERIMENTAL OVALBUMIN-INDUCED ALLERGIC INFLAMMATION

The actual problem of modern medicine is the reaction of Bronchus associated lymphoid tissue in airways chronic allergic diseases, because the full functioning of the respiratory system depends on the state of its local immune system. The aim – to study morphological changes in Bronchus associated lymphoid tissue of guinea pigs in the dynamics of experimental ovalbumin-induced allergic inflammation. Material and Methods. We have studied the lung of 48 guinea pigs, using histological and morphometric methods, under conditions of experimental ovalbumin-induced allergic inflammation. To assess the structural and functional rearrangement of pulmonary lymphoid nodules, their diameter and number were determined. Results. We have shown that sensitization and allergization with ovalbumin leads to a significant structural and functional rearrangement of Bronchus associated lymphoid tissue of guinea pigs in the form of the elevation in their number and diameter. We found more pronounced morphological changes in the late period of development of allergic inflammation in peribronchial lymphoid nodules, confirmed by the maximum magnification factor – 2.6 (p*/**<0.001) of the diameter of peribronchial lymphoid nodules in the 4th experimental group compared to the control. Conclusions. Sensitization and inhalation with ovalbumin leads to structural reorganization of Bronchus associated lymphoid tissue of guinea pigs in the form of the elevation in their number and diameter, had the unidirectional staged character depending on localization of lymphoid nodules and the duration of the experiment and claimed proliferative changes in the cellular adaptive link of local lung immunity of guinea pigs in late period of allergic inflammatory process.

Histochemical Studies on Post Natal Development of Gut Associated Lymphoid Tissue (GALT) of Intestine of Pati Duck (Anas platyrhynchos domesticus) of Assam

Background: The Pati duck constitutes a major indigenous duck variety in the state of Assam. The study of the gut associated lymphoid tissue (GALT) of Pati duck of Assam is of great value in regard to normal academic and bio-medical research aspects. It is also pre-requisite for correct diagnosis and evaluating the treatment of certain diseases like duck virus enteritis, duck cholera, aflatoxicosis, botulism etc, caused by different types of pathogens, food poisoning and food allergy. Methods: The study was conducted on Pati duck of Assam in where 45 numbers of ducks were selected by irrespective of sex at different stages of development. The birds were divided into five groups depending on its age viz., 1st week, 4th week, 16th week, 24th week and 42nd weeks old. The pieces of gut having lymphoid tissue or Peyer’s patches were collected immediately after slaughter. Samples were made cryosections (-20oC) at 10µm in thickness and were temporally stored at (-22oC). The histochemical staining was done after that. Result: The acid phosphatase activity was weak in the lymphoid follicles of 1st and 4th week of age of Pati duck, while its activity was moderate in 16th, 24th and 42th week of age.The alkaline phosphatase activity was moderate reaction in the lymphoid follicles of 1st and 4th week of age of Pati duck, while its activity was intense in 16th, 24th and 42th week of age of duck. The lymphoid follicles of both Peyer’s patches and solitary lymphoid nodules were showed moderate activity for adenosine tri-phosphatase activity in 1st and 4th week old Pati duck and strong activity in 16th, 24th and 42th week of age of Pati duck, respectively. The lymphoid nodules of intestine showed strong reaction for non-specific esterase activity in all the age groups of Pati duck.

Immune competence and spleen size scale with colony status in the naked mole-rat

Naked mole-rats (NM-R; Heterocephalus glaber) live in multi-generational colonies with a social hierarchy, show low cancer incidence and long life-spans. Here we asked if such extreme physiology might have an immune component. The spleen is the largest lymphoid organ and plays an essential role in response to immunological insults and may participate in combating cancer and slowing ageing. We investigated the anatomy, molecular composition and function of the NM-R spleen using RNA-sequencing and histological analysis in healthy animals. We found that spleen size in healthy NM-Rs varies considerably. We therefore classified NM-Rs according to spleen size as NM-Rs with small spleens or enlarged spleens. Animals with enlarged spleens showed potentially better anti-microbial profiles and were much more likely to have a high rank within the colony. Splenomegaly was associated with infection in sick NM-Rs, but not in NM-Rs with enlarged spleens. In all healthy NM-Rs splenic erythropoiesis, megakaryopoiesis and myelopoiesis were increased, but B lymphopoiesis was reduced and splenic marginal zone showed markedly altered morphology when compared to other rodents. However, in NM-Rs lymphocytes were found in secondary sites such as lymph nodes, gut lymphoid nodules and thymus. Thus, the NM-R spleen is a major site of adult hematopoiesis under normal physiological conditions. Overall, the NM-R immune system seems to rely mainly on innate immune responses with a more restricted adaptive immune response. We propose that the anatomical plasticity of the spleen might be regulated by social interaction and gives immunological advantage to increase the life-span of higher ranked animals.

Content and location of lymphocyte subpopulations with markers CD4+, CD8+ and CD20+ in the esophageal tonsil of chickens and the Meckel diverticulum of ducks

Immune formations of birds' digestive organs, including the esophageal tonsil and Meckel’s diverticulum, protect the body from foreign antigens that enter the body with food and water and play an important role in maintaining the genetic constancy of its internal environment. This unique property of the immune system is formed during ontogenesis and is associated with maintaining the selection of lymphocyte clones that are able to respond to foreign antigens and carry out a specific immune response of two types: humoral and cellular. This article presents the results of a study of T- and B-lymphocyte subpopulations of the esophageal tonsil of Shever 579 cross chickens at the age of 25, 180 and 300 days, the Meckel diverticulum of the Blagovarsky cross ducks at the age of 30, 150 and 180 days. Immunohistochemical and statistical research methods were used to determine the localization and quantitative parameters of cell populations of lymphocytes (CD4+, CD8+, CD20+) using monoclonal antibodies and the DAKO EnVision FLEX+ imaging system (Dako Cytomation, Denmark). Separate subpopulations of T-lymphocytes (CD4+ - helpers, CD8+ -cytotoxic / T-suppressors) and mature B-lymphocytes (CD20+) were found in the esophageal tonsil and Meckel diverticulum of birds. Their presence confirms that antigen-independent proliferation and differentiation of lymphocytes into effector cells occur in the immune formations of the digestive system. The lymphoid tissue of these formations is represented mainly by a well-defined diffuse form and nodules with light centers (secondary). In the esophageal tonsil of chickens, these structures are located in the tunica mucosa and tela submucosa, and in the Meckel diverticulum of ducks – also in the tunica muscularis. The content of lymphocytes with these markers predominates in diffuse lymphoid tissue compared to that in secondary lymphoid nodules. In the diffuse lymphoid tissue of the esophageal tonsil, lymphocytes are located mainly near the adenomeres and excretory ducts of the esophageal glands, blood vessels, and under the surface epithelium, and in Meckel’s diverticulum – around the crypts, in their epithelium and in the epithelium of the villi. They are also found in the light centers of lymphoid nodules and on their periphery. The indices of the content of lymphocytes with the indicated markers in the esophageal tonsil and Meckel diverticulum which we determined were associated with age characteristics of the poultry in the postnatal period of ontogenesis. According to our observations, the content of CD20+ lymphocytes was the highest, while the populations of CD4+ and CD8+ lymphocytes were much smaller. This indicates an increase in the activity and predominance of the humoral immunity over the cellular one. The content of CD20+ lymphocytes was highest in birds at the age of 180 days, that is, during their sexual maturity. The data presented in the work can be used by morphologists researching the organs of the immune system, immunologists, poultry specialists involved in breeding, using and raising poultry and in educational work.

THE GLANDS AND LYMPHOID STRUCTURES OF THE HUMAN URINARY BLADDER IN SPHINCTERS ZONES

We have studied the glands and lymphoid structures of urinary bladder of human in sphincters zones with morphological methods on 38 preparations of different ages (from newborn till to senile period). the glands (by RD Sinelnikov method) and lymphoid structures were investigated by macro-microscopic methods after stained by Hellman method. The micro preparations incisions sphincters zones of a urinary bladder in the thickness 5-7 microns were stained with hematoxylin-eosin, by Van-Gizon, Veygert and Kreyberg methods. In the sphincters zones the glands are in close microtopographical relations with lymphoid structures (lymphoid nodules and diffuse lymph tissue) and as a rule the glands are located densely. Without dependence from age, microanatomy parameters of the glands and lymphoid structures of the sphincters zones of urinary bladder are more than in outside. Dimensional indicators at right and left ureters sphincters almost correspond. It is connected by a similar design. At senile age, lymphoid structures in sphincters of a urinary bladder are single or absent.

Functional zones of Peyer’s patch (PPs) in rabbits’ caecum

A feature of rabbit gut-associated lymphoid tissue is that its structure is more developed than in other animal species. In rabbits it is composed of sacculus rotundus, vermiform appendix and Peyer’s patches. These immune formations contain an organized component of lymphoid tissue – lymphoid nodules (B-cell zone) and interfollicular region (T-cell). Secondary lymphoid nodules with germinal centers presented in them are formed due to antigen stimulation. The caecum of Hyplus rabbits at the age of 30 -, 60 - and 90-days was investigated. Each age group consisted of 5 rabbits. Experimental rabbits are clinically healthy, unvaccinated and untreated against ecto- and endoparasites. Peyer’s patches of the caecum were selected for the study and fixed in 10% of formalin. Subsequently, the specimens stained with hematoxylin-eosin were prepared from the obtained samples. On the 30th day of life, Peyer’s patches in the cecum were detected by gross examination. On the histological level, they had formed interfollicular region and lymphoid nodules. In turn, lymphoid nodules were divided into primary and secondary ones. A well-defined mantle zone and germinal centers were observed in the secondary lymphoid nodules. The regularities of their area indicators increase (mean value, median and interquartile range (IQR)) and their correlation were studied. The most intensive growth of the mantle area and the germinal center was observed from the 30th to the 60th day. The relative area of the mantle zone and the germinal center as part of the secondary lymphoid nodule was determined. Its value did not change during the experimental period.

Histological studies on the oesophageal tonsils of broiler ducks

Histomorphological study was conducted on the oesophageal tonsils in six broiler Vigova Super-M ducks of six to eight weeks age. The location of the tonsil was at the junction between oesophagus and proventriculus. In histological sections six to eight isolated tonsillar units were seen in the lamina propria near the base of the oesophageal folds. Each tonsillar unit consisted of a crypt lined by lymphoepithelium and surrounded by dense lymphoid tissue. The tonsillar units were seen encapsulated by connective tissue and composed of many large lymphoid nodules separated by internodular areas. The secretory portion of the mucosal glands of the oesophagus were firmly associated with the lymphoid tissue and the cylindrical epithelium was transformed to lymphoepithelium. The oesophageal tonsils offered immunological protection at the entrance of stomach. Keywords: Oesophageal tonsils, Histomorphology, Ducks

Characteristics of Intestinal Mucosa-associated Lymphoid Tissue in Experimental Trichinellosis in Rats

The purpose of the research is studying intestinal mucosa-associated lymphadenoids (MALT) at trichinellosis. Materials and methods. The number of lymphoid nodules and Peyer’s patches was counted by grossing and microscope slides of intestinal specimen. We investigated their syntopy and morphological traits in Trichinella-infected and control animals. All morphological structures were described in accordance with anatomical, immunological and histological terminology. Results and discussion. The number of lymphoid nodules in the intestinal wall thickness increased by 1.63 times in the experimental group. The changes involved the syntopy of lymphoid tissue. There was an even distribution of lymphoid nodules being concentrated in some segments in the form of Peyer’s patches. The size of the grouped nodules in the experimental trichinellosis increased 1.31 times in the small intestine, and 1.26 times in the straight intestine. It was found that the MALTs were sensitive to the infection. Immunomorphological studies of the MALT should be considered in the development of safe complex drugs, immunostimulants or vaccines. Further, the condition of the MALT should be taken into account in the pathogenesis of trichinellosis along with classical methods such as parasitological (larvae or egg counts), immunological, immunohistochemical or other methods.

IMMUNOHISTOCHEMICAL CHARACTERISATION OF LYMPHOID POPULATIONS IN RABBIT JEJUNAL PEYER’S PATCH

Rabbits are an important livestock animal species, which are used for their meat and fur. Nowadays they are also becoming more popular as pets. Furthermore, rabbits are commonly used in research, inter alia in immunological studies and for studying pathogenesis of human and animal diseases. The lymphoid tissue is abundant in the rabbit intestine and a lot of it is concentrated in Peyer's patches, the majority of which is located in the jejunum. Understanding of the rabbit Peyer's patches functions is essential for the prevention and treatment of their diseases. In order to enhance it, accurate knowledge of its lymphocyte population composition is needed. At present, the cellular composition of the rabbit gut-associated lymphoid tissue remains insufficiently studied. Therefore, the aim of our study was to establish the content and localization of lymphoid populations in the domestic rabbit jejunal Peyer’s patches. We performed immunohistochemical studies using monoclonal antibodies CD3, CD10 and CD20 (DAKO, Denmark) to identify the distribution of lymphoid populations in jejunal Peyer's patches of a mature domestic rabbit. The results, obtained in our study, complement the existing data and determine the main lymphoid populations in the rabbit jejunal Peyer's patches. The presented data are fundamental for further studies of the rabbit gut-associated lymphoid tissue. We found that lymphoid nodules of jejunal Peyer's patches contains a predominant CD20+ cell population (B cells). It also contains many CD10+ cells (precursors of T cells and B cells), which are mostly concentrated in the germinal centers of lymphoid nodules. In the diffuse form of the lymphoid tissue the vast majority of cells are CD3+ cells (T cells)