Late effect of carbon disulfide on the lymph nodes in rats]

Cell composition of the cortical plateau, medullary cords and lymphoid nodules++ has been determined in 180 Wistar rats in 2 weeks, 1 and 3 months after inhalation of carbon disulfate vapour for 2, 7 and 14 days in a maximum permissible concentration (1 mg/m3) and in the control group. In 2 weeks after cessation of the vapour inhalation activity of lymphocytopoiesis, blastopoiesis, cell differentiation decreases, macrophagal and plasmocytic reactions are weakly manifested. In 1 month certain signs of compensatory-adaptive reaction are noted; they are seen as increasing proliferative processes and activation of cell differentiation in the lymphoid nodules++ and a sharp plasmatization of the medullary cords. In 3 months after the experiment retardation of lymphocytopoiesis is still definitely manifested in the cortical plateau and medullary cords and essential destructive processes are observed against the background of local increase of the functional activity of the lymphoid nodules++.     

The microscopic anatomy of the human pharyngeal tonsil in the postnatal period of ontogeny

Histological sections of the pharyngeal tonsil (PhT) have been investigated in 55 corpses of persons of both sex and various age, that had no disease connected with lesions of the PhT by the time of their death. The aim of the work is to determine relative areas of each structural element of the PhT in comparison to the whole section area taken as 100%. The PhT lymphoid tissue reached its maximal relative development at the first childhood. Then the lymphoid tissue area in the PhT histological sections decreases gradually, making already in the second mature age one half of the tonsil section area, and in the elderly age--nearly one-fourth. The decrease of the relative lymphoid tissue area takes place at the expense of decreasing area of the lymphoid nodules. The relative area of the connective stroma increases inversely to the relative decrease of the lymphoid tissue area parameters. The germinative centers in the lymphoid nodules are absent in newborns and old persons. The greatest value of the relative area of the germinative centers falls to the early infancy. The lymphoid nodules with the germinative centers, according to their relative area during all age periods, besides the newborn period, the second mature, elderly and old age periods, essentially exceed the area, that occupy the nodules without the germinative centers on the PhT sections.     

Microscopic anatomy of small-intestinal lymphoid patches in children and adults

Longitudinal histological sections of lymphoid patches (LP) in the small intestine, stained after van Gieson and with hematoxylin--eosin, obtained from 105 corpses of persons at the age of 0 up to 90 years have been studied. The LP parenchyma is presented as accumulation of lymphoid nodules++ with a germinative center, or without it and diffuse lymphoid tissue. The lymphoid nodules++ situate both in the mucous membrane and in the submucous tela of the small intestine. The area of the LP components in the newborns is the greatest--84% from the whole area of the LP section. During the human life it decreases and by the old age it makes 47%. The lymphoid nodules++ area with the germinative center in the newborns makes 21% from the area of the LP section, in children from 1 to 3 years of age it increases up to 50%, then it gradually decreases and in the elderly age it makes only 3.8%. The diffuse lymphoid tissue in the LP composition is revealed in all age periods. Size of the lymphoid nodules++ patches, situating in the jejunum and ileum walls in the newborns is the same. In children at the age of 10 days--12 years the LP nodules++ in the ileum are larger than those in the sejunum. The size of the LP noduli increase up to the period of the second childhood then decreases. The height of the lymphoid noduli in persons of mature, elderly and old ages decreases twice in comparison with the children of 3-12 years of age.     

Cellular composition of tracheal lymphoid tissue in children in their first year of life]

By means of morphometrical methods in histological preparations the quantitative relations of various cell types of lymphoid formations has been studied in newborns and in suckling children. The trachea in the newborns practically does not possess any morphological substrate in the form of lymphoid accumulations, responsible for immune defense of the organ from any external influence. Development of the lymphoid tissue begins in the suckling age and its cytoarchitectonics depends on their localization in the organ's wall. A special place among the accumulations of the lymphoid cells occupy connective tissue spaces of the tracheal glands, where besides lymphocytes and fibroblasts a great amount of plasma cells is situated. Under epithelium these cells are in the least amount, in the prenoduli they are of an intermediate amount. In all the lymphoid structures investigated reproductive function is absent; this is proved by absence of blasts and mitotically dividing cells. Increase in amount of the tracheal lymphoid formations in all age groups studied takes place at the expense of cells migration across blood vessels.     

Age-related aspects of the anatomy and topography of the human tubal tonsil

The tubal tonsil (TT) has been investigated in 60 preparations of the auditory tube (right and left), obtained from 30 corpses of persons at various age, those died from traumas and having neither any pathological changes in their acoustic organs, nor chronic inflammatory diseases by the time of death. The TT is presented as a solid or interrupted lymphoid tissue plate, situating in the mucosal membrane in the area of the pharyngeal opening to some extent in the inferior, posterior and anterior walls of the auditory tube. In newborns the TT is presented as a diffuse lymphoid tissue, where lymphoid nodules begin to form. The greatest amount of the lymphoid nodules in the TT are revealed in the infantile age and this sign is kept during subsequent age periods, including the first period of mature age. During these age periods on the surface of the mucosal membrane in the area of the pharyngeal opening numerous small eminences are seen--tubercles, corresponding in their position to lymphoid nodules under them. Beginning from the second mature period and up to old age the amount and size of the lymphoid nodules in the TT decreases. At that time on the surface of the mucosal membranes in the area of TT only single tubercles are revealed.     

Cellular composition of structural components of the lymph nodes of rats during rehabilitation after dimethyl sulfate poisoning

By means of microanatomical methods the inferior tracheobronchial lymph nodes have been investigated in 48 Wistar rats in 2 weeks and 3 months after discontinuance of inhalation of dimethylsulfate (DMS) vapours for 2 and 14 days by the animals in concentration 2.0 mg/m3, that is to say during rehabilitation period. Comparison of relative parameters of the structural components areas and cell composition of the lymph nodes has been carried out. During rehabilitation period after DMS inhalation for 2 days the cortical and medullary areas in histological preparations do not essentially differ from corresponding parameters of an acute experiment (2 days, 2.0 mg/m3, without rehabilitation). Amount (%) of cells with mitotic figures in the lymphoid nodules++ increases in 2 weeks and in 3 months. Contents of poorly differentiated cells during rehabilitation periods increase in the cortical plateau, but keeps nearly at the same low level as during the acute experiment in the lymphoid nodules++. In 2 weeks after DMS influence for 14 days, the cortical and medullary area in the histological preparations reach the control levels. In the lymphoid nodules++ a relative amount of reticular, poorly differentiated, mitotically dividing cells increases, and in the medullary cords contents of middle and small lymphocytes become greater in comparison with the acute experiment (14 days, 2.0 mg/m3, without rehabilitation).(ABSTRACT TRUNCATED AT 250 WORDS)     

Evidence of a true pharyngeal tonsil in birds: a novel lymphoid organ in Dromaius novaehollandiae and Struthio camelus (Palaeognathae)

ABSTRACT: BACKGROUND: Tonsils are secondary lymphoid organs located in the naso- and oropharynx of most mammalian species. Most tonsils are characterised by crypts surrounded by dense lymphoid tissue. However, tonsils without crypts have also been recognised. Gut-associated lymphoid tissue (GALT), although not well-organised and lacking tonsillar crypts, is abundant in the avian oropharynx and has been referred to as the "pharyngeal tonsil". In this context the pharyngeal folds present in the oropharynx of ratites have erroneously been named the pharyngeal tonsils. This study distinguishes between the different types and arrangements of lymphoid tissue in the pharyngeal region of D. novaehollandiae and S. camelus and demonstrates that both species possess a true pharyngeal tonsil which fits the classical definition of tonsils in mammals. RESULTS: The pharyngeal tonsil (Tonsilla pharyngea) of D. novaehollandiae was located on the dorsal free surface of the pharyngeal folds and covered by a small caudo-lateral extension of the folds whereas in S. camelus the tonsil was similarly located on the dorsal surface of the pharyngeal folds but was positioned retropharyngeally and encapsulated by loose connective tissue. The pharyngeal tonsil in both species was composed of lymph nodules, inter-nodular lymphoid tissue, mucus glands, crypts and intervening connective tissue septa. In S. camelus a shallow tonsillar sinus was present. Aggregated lymph nodules and inter-nodular lymphoid tissue was associated with the mucus glands on the ventral surface of the pharyngeal folds in both species and represented the Lymphonoduli pharyngeales. Similar lymphoid tissue, but more densely packed and situated directly below the epithelium, was present on the dorsal, free surface of the pharyngeal folds and represented a small, non-follicular tonsil. CONCLUSIONS: The follicular pharyngeal tonsils in D. novaehollandiae and S. camelus are distinct from the pharyngeal folds in these species and perfectly fit the classical mammalian definition of pharyngeal tonsils. The presence of a true pharyngeal tonsil differentiates these two ratite species from other known avian species where similar structures have not been described. The pharyngeal tonsils in these ratites may pose a suitable and easily accessible site for immune response surveillance as indicated by swelling and inflammation of the tonsillar tissue and pharyngeal folds. This would be facilitated by the fact that the heads of these commercially slaughtered ratites are discarded, thus sampling at these sites would not result in financial losses.     

Detection of intraepithelial and stromal Langerin and CCR5 positive cells in the human endometrium: potential targets for HIV infection

Both the upper (endocervix and uterus) and lower (ectocervix and vagina) female genital tract mucosa are considered to be target sites for sexual transmission of HIV. There are a few reports on the T cell and antigen-presenting cell distribution in human endometrial tissue however, there is little known about the expression of the HIV co-receptor CCR5 and HIV-binding C-type lectin receptors on endometrial cell subsets. We therefore assessed endometrial tissue sections from HIV seronegative women undergoing hysterectomy of a benign and non-inflammatory cause for phenotypic characterization of potential HIV target cells and receptors by immunohistochemistry. Langerin was expressed on intraepithelial CD1a+CD4+ and CD11c+CD4+ Langerhans cells. Furthermore, CCR5+CD4+CD3+ T cells, DC-SIGN+MR+CD11c+ myeloid dendritic cells and MR+CD68+ macrophages were found within or adjacent to the epithelium of the uterine lumen. In addition, occasional CD123+ BDCA-2+ plasmacytoid dendritic cells were detected deep in the endometrial stroma. Both T cells and several antigen-presenting cells were detected in lymphoid aggregate formations in close proximity to the epithelial lining. The finding of intraepithelial and stromal Langerin+ cells as well as CCR5+ CD4+ T cells is novel for human endometrium.     

Lymphoid nodules of the urinary bladder in man

Basing on macro- microscopical investigation of the urinary bladder in 94 persons, died at the period of birth up to old years and by the time of death having not any disease of the urinary apparatus, structure and topography of the lymphoid nodules, their amount, density of distribution in the mucous membrane of various parts of the organ have been studied. The germinative centers in the lymphoid nodules of the urinary bladder are not revealed. The external appearance of the nodules is not the same; some have clear contours others have no clearly manifested borders. We call them prenodules. The lymphoid nodules are situated near to each other without any definite order. And only near the ureteral openings they are always revealed in a small amount, in the area of the triangle; they are oriented, as a rule, from the ureteral openings towards the exit from the urinary bladder. The amount of the lymphoid nodules in the organ's wall varies (at an average) from 18, in newborns, up to 415, in adolescents, and up to 129, in old persons. Distribution density of the lymphoid nodules in the fundal area of the urinary bladder is somewhat greater, than in its superior parts. The size of the lymphoid nodules during all age periods is not more than 900 mcm.     

Motile cells in the mucosa of the cloacal urodaeum and proctodaeum of the hen

Summary Motile cells (mast cells, granulocytes, lymphoid cells) are described in the mucosa of the cloacal urodaeum and proctodaeum of the female domestic fowl. Diffuse lymphoid tissue with lymphatic nodules occurs in the urodaeum at the ureteral ostium. Small local aggregations of lymphoid tissue can be observed in the mucosa of the proctodaeum. Cells originating from these sites penetrate the basal lamina of the epithelium and are then found between the epithelial cells.In the subepithelial layers the motile cells sometimes are in contact with each other. Mast cells (tissue basophils) form contact zones, resembling desmosomes or half desmosomes, with smooth muscle cells. In the mast cells three types of granules can be distinguished. Their ultrastructure is discussed in comparison with that in similar cells of the guinea pig.Dedicated to Professor Dr. med. M. Watzka in honor of his 75th birthday     

Formation of spontaneous and immune rosettes by the cells of the thymus and other formations of the rabbit lymphoid system]

Only T1--RFC (rosette-forming cells) are revealed in the thymus of nonimmunized rabbits. Their number is 2--2.5 times less than in the palatine tonsils, submaxillary lymph nodes and the spleen. T2--RFC are present in these lymphoid formations. There is an increase in the T1--RFC in the thymus after the intravenous immunization of rabbits with sheep erythrocytes. In other lymphoid formations the correlation of the population of cells of the thymus origin altered as a result of increase in the number of T2--RFC. B--RFC accumulated in considerable amounts. Dynamics of T2 and B--RFC accumulation in the lymphoid formations corresponded to the highest antibody titres in the rabbit blood. In the formation of primary immune response the amount of the T1 and T2-RFC in the formations of rabbit lymphoid system depended on the dose of the antigen.     

Morphofunctional changes in the lymphoid tissue of the respiratory organs in gamma-globulin administration

By means of macro-microscopic, histologic, radioautographic and immunomorphologic methods, three forms of the lymphoid tissue structural organization have been revealed in the rat respiratory organs: a lymphoid cluster, a lymphoid follicle and a lymphoepithelial nodule. After gamma-globulin is administered intranasally, the ratio of the lymphoid cells in the organs mentioned changes: the number of small lymphocytes decreases, while that of middle, large lymphocytes and blast cells increase. The lymphoid follicles consist of a central and a marginal zones, in the lymphoepithelial nodules the subepithelial and paranodular zones also exist. The gamma-globulin administration stimulates DNA synthesis by the cells of the lymphoid type and their proliferation; that results in increasing number of the antibody-synthesizing cells and is accompanied with an increasing titre of antibodies in washing from the bronchial tree. At a repeated stimulation, the processes are more intensive and develop more quickly.     

Microscopic endometrial perivascular epithelioid cell nodules: a case report with the earliest presentation of a uterine perivascular epithelioid cell tumor

ABSTRACT: Perivascular epithelioid cell (PEC) tumors (PEComas) are a family of related mesenchymal tumors composed of PECs which co-express melanocytic and smooth muscle markers. Although their distinctive histologic, immunohistochemical, ultrastructural, and genetic features have been clearly demonstrated, their histogenesis and normal counterpart remain largely unknown. Precursor lesions of PEComas have rarely been reported. We herein describe a tuberous sclerosis patient with microscopic PEC nodules in the endometrium of adenomyosis, pelvic endometriosis, an ovarian endometriotic cyst, and the endometrium of the uterine cavity. The nodules showed a mixture of spindle-shaped and epithelioid cells concentrically arranged around small arteries. The cells exhibited uniform nuclei, light eosinophilic cytoplasm, and immunoreactivity with HMB-45 and CD10. Some nodules revealed continuity with a PEComa in the myometrium. These findings support microscopic endometrial PEC nodules possibly being precursor lesions of uterine PEComas. The wide distribution of the nodules in the pelvis may be related to the multicentricity of PEComas in tuberous sclerosis patients. Owing to the immunoreactivity with CD10, microscopic endometrial PEC nodules may be misinterpreted as endothelial stromal cells unless melanocytic markers are stained. To the best of our knowledge, this is a case with the earliest manifestation of PEC lesions occurring in the endometrium.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9658280017862643.     

Cytopathology and diagnostics of Warthin's tumour

Warthin's tumour (WT) is a benign epithelial salivary tumour, one type of salivary adenoma. Histologically, WT is structured of two components, epithelial tissue that often lines cystic formations and lymphoid tissue in the tumour stroma. FNA is a reliable diagnostic approach in the diagnosis of salivary gland lesions allowing a highly accurate categorization of benign tumour‐like lesions, benign tumours and malignant tumours. In the proposed Milan reporting system of salivary gland lesions, WT is categorized in the IVA group of benign neoplasms. Accurate cytological diagnosis is straightforward when three characteristic components are present: oncocytes, either isolated or associated in clusters, lymphocytes and lymphoid cells and often an inflammatory/necrotic‐like substance. Also, specific features of scintigraphy and radiological imaging contribute to the diagnosis of WT. WT is categorized according to Seifert G. et al in 4 types, depending on the proportions of the epithelial component and lymphoid stroma. Differential cytopathological and pathohistological diagnosis include other salivary gland lesions with lymphoid, oncocytic epithelial and cystic components. In some cases, such as the metaplastic WT variant, there are additional cytopathological and histological diagnostic difficulties. Moreover, bilateral, multicentric or multiple and infrequently seen extra‐salivary localizations of WT are associated with further cytopathological diagnostic difficulties. Also, a rare possibility of malignant transformation of the epithelial or lymphoid component of WT as well as possible association with other primary tumours remains a challenge in accurate cytopathological and histological diagnosis of WT.     

Phylogeny of Gut-Associated Lymphoid Tissue

Gastrointestinal (GI) tracts from four anuran and four urodelespecies were examined macroscopically and histologically fromthe esophagus to the cloaca. Anatomic observations were facilitatedby treating the GI tracts with acetic acid, a procedure whichremoves gut epithelium and exposes underlying structures. Histologicanalysis involved routine as well as specific histochemicaltechniques. Detailed observations reveal that anuran amphibianspossess nodular, well-organized gut-associated lymphoid tissue(GALT) throughout their GI tracts. In striking contrast, nosuch patterns of lymphoid tissue have been noted in the Urodela. Similar techniques have revealed the location of lymphoid tissuesin the urogenital system (e.g., cloaca and bladder) of advancedanurans. These nodules appear to be lacking in the primitiveanuran Xenopus and in all the urodele species we examined. Preliminary observations have confirmed GALT and urogenital-associatedlymphoid tissues in the snapping turtle.     

A morphologic study of bronchus-associated lymphoid tissue in turkeys

Bronchus-associated lymphoid tissue (BALT) in normal turkeys of ages 1 day and 1, 2, 3, 4, 8, and 18 weeks was examined by light microscopy and by scanning and transmission electron microscopy. Turkey BALT resembled other mucosa-associated lymphoid tissues; it was made up of a population of lymphocytes covered by a specialized epithelium different from typical pseudostratified ciliated columnar bronchial epithelium. There were distinct age-related differences in BALT structure. Bronchus-associated lymphoid nodules were larger and more numerous in older turkeys. In 1-day- to 2-week-old turkeys, the primary cell type of BALT epithelium was nonciliated cuboidal; in 2-week old turkeys it was squamous; and in turkeys older than 4-weeks of age, the epithelium was primarily ciliated columnar. In 1- to 4-week old turkeys, large numbers of intraepithelial lymphocytes disrupted the normal organization of the epithelium. In older turkeys, epithelial and lymphoid cells were in discrete compartments separated by connective tissue. Lymphocytes in 1-day-old turkeys were found in loose aggregates around venules and within the epithelium. In 1-week old turkeys, lymphocytes were organized into compartments of morphologically similar cells. By 3-weeks of age, lymphocytes were present in distinct germinal centers. Epithelial cells of BALT did not have large numbers of apical vesicles and thus were not structurally specialized for antigen uptake by endocytosis. However, the epithelial barrier appeared to be disrupted over lymphoid nodules, suggesting that antigen would be readily available to lymphocytes and phagocytes in BALT. Age-related differences in turkey BALT structure may have functional consequences with respect to the respiratory immune response.     

The development of lymphoid and haemopoietic tissues in pig fetuses

This paper presents the results of the development of lymphatic and haemopoietic organs in pig fetuses of various ages. The thymus appears to be the first lymphatic organ in these fetuses as well as in other animal species so far studied. On the 77th day the thymus is fully morphologically developed. The accumulations of lymphocytes in the spleen appear on the 70th day. The development of periarteriolar formations takes place around the 84th day of gestation. Further development of lymphoid tissue in the lymph nodes, tongue (tonsilla lingualis) and intenstine is described. Lymphatic follicles were observed both in the tongue and the small intestine on the 77th day. The dynamics of haemopoietic activity in the liver and bone marrow is characterized. The germinal centers in lymphoid folicles were never observed as well as cells of the plasmatic series.     

Phagocytosis in the spleen of the sunfish Lepomis spp.

A histological investigation of the filtering function of the spleen of the sunfish Lepomis spp. was conducted by light, scanning, and transmission electron microscopy. The parenchyma of the organ is predominantly red pulp, a system of splenic cords and sinuses. The white pulp consists of loose lymphoid tissue which forms a cuff around the pulp arteries. Filtering of particulate matter from the blood occurs in the red pulp by phagocytes of the pulp cords and ellipsoids (periarterial macrophage sheaths). The ellipsoids are pale-staining cuffs of macrophages and reticular cells in a framework of reticular fibres surrounding the arterial capillaries. Destruction of effete blood cells (especially erythrocytes) is confined to the pigment nodules; particulate matter is not taken up by the nodules. These yellow-brown bodies are dispersed throughout the red pulp and are bounded by a reticular capsule. They contain masses of phagocytes and have the appearance of a morula. They are associated with blood vessels and are surrounded by sinusoids. Prussian Blue stain shows the presence of haemosiderin within their phagocytes. The phagocytes of the pigment nodules are filled with inclusions such as residual bodies, siderosomes, and fragments of erythrocytes. The early filtering of particulate matter by the phagocytes of the pulp cords and ellipsoids may allow for a more efficient phagocytosis of erythrocytes by the pigment nodules, followed by storage and reutilization of iron-containing compounds uncontaminated by other phagocytosed material.     

Postnatal development of bronchus-associated lymphoid tissue (BALT) in the rat, Rattus norvegicus.

The pattern of development of bronchus-associated lymphoid tissue (BALT) in specified-pathogen-free and conventional (non-barrier maintained) rats over the initial 4 weeks of life appeared to be similar. BALT first appeared around the 2nd week of life and increased in amount over the following 2 weeks. Overlying large nodules of BALT the bronchial epithelium becomes infiltrated by lymphocytes to form a lymphoepithelium. This transformation occurs earlier in conventional rats, possibly because of the differing antigen levels to which they are exposed.