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PubMed1989

Postnatal development of mucosa-associated lymphoid tissues in chickens.

The postnatal development of chicken mucosa-associated lymphoid tissues of the eyes, lungs, and intestines were investigated with monoclonal antibodies specific for either all leucocytes, B lymphocytes, mononuclear phagocytes, IgM, IgG, or IgA. Attention has been paid to the relation of lymphoid infiltrates with their surrounding mucosae, the segregation into B-cell and T-cell areas, development of germinal centers, and secretory immunoglobulins. Abundant secretory IgM and IgA was detected in the epithelium of the Harderian glands in the orbits, even though they lacked large leucocyte infiltrates with germinal centers. Lymphoid tissues in the mucosae of lungs and intestines developed separate B-cell and T-cell areas. The proventriculus, Meckel's diverticulum, and Peyer's patches generally contained germinal centers from 12 weeks of age on. Because chickens as young as 2 weeks old had germinal centers in bronchus-associated lymphoid tissue and cecal tonsils, these areas were probably highly stimulated by antigens. Isotype-specific monoclonal antibodies were used to detect IgM-, IgG-, and IgA-bearing follicular cells in the same germinal center.

Animals↗
PubMed1987

Minor salivary gland duct-associated lymphoid tissue (DALT) in monkeys changes with age.

The duct-associated lymphoid tissue (DALT) of minor salivary glands (MSG) is accessible to oral antigens by retrograde passage. DALT responds immunologically to such purely local and duct-derived antigenic stimuli. This study addressed the question as to whether DALT, like other mammalian lymphoid tissues, would change with age. Labial and buccal mucosae of eight Macaca fascicularis animals of known age were processed for light microscopy by Epon embedding. Sections of approximately 1-2 microns thick were prepared, and a total of 144, more or less equidistant, labial and 63 buccal sections were selected and analyzed for various tissue components, by means of morphometric point-counting. The raw data were transformed into stereological parameters. The results showed that DALT and interacinar plasma cells are totally absent in the newborn monkey. They begin to appear early in life and reach a maximum volume density by one year of age. With further increasing age, the DALT volume showed a sharp decline, followed by a plateauing from year 3 onward, while the plasma cell concentration remained stable. This change was more pronounced in the labial mucosa. These observations on the age-related changes of simian DALT are suggestive of its antigen-induced and antigen-dependent nature. DALT, being part of the gut-associated lymphoid tissue, may play a substantial role in the local immuno-surveillance of the oral cavity.

Aging↗
PubMed1988

Spirochetal antigens and lymphoid cell surface markers in Lyme synovitis. Comparison with rheumatoid synovium and tonsillar lymphoid tissue.

Using monoclonal antibodies to spirochetal antigenes and lymphoid cell surface markers, we examined the synovial lesions of 12 patients with Lyme disease, and compared them with rheumatoid synovium and tonsillar lymphoid tissue. The synovial lesions of Lyme disease patients and rheumatoid arthritis patients were similar and often consisted of the elements found in normal organized lymphoid tissue. In both diseases, T cells, predominantly of the helper/inducer subset, were distributed diffusely in subsynovial lining areas, often with nodular aggregates of tightly intermixed T and B cells. IgD-bearing B cells were scattered within the aggregates, and a few follicular dendritic cells and activated germinal center B cells were sometimes present. Outside the aggregates, many plasma cells, high endothelial venules, scattered macrophages, and a few dendritic macrophages were found. HLA-DR and DQ expression was intense throughout the lesions. In 6 of the 12 patients with Lyme arthritis, but in none of those with rheumatoid arthritis, a few spirochetes and globular antigen deposits were seen in and around blood vessels in areas of lymphocytic infiltration. Thus, in Lyme arthritis, a small number of spirochetes are probably the antigenic stimulus for chronic synovial inflammation.

Adolescent↗
PubMed1997

Isolation and characterization of mouse nasal-associated lymphoid tissue.

A method for isolation of mouse nasal-associated lymphoid tissue (NALT), which is a principal mucosal lymphoid tissue of the respiratory tract in rodents, was developed. The paired lymphoid organs could be separated from the upper jaw by peeling away the palate where NALT was localized bilaterally on the posterior side. About 3 x 10(5) lymphocytes could be obtained from one NALT fragment. The NALT lymphocyte fraction from normal BALB/c mice contained T- and B-cells in about equal numbers, and contained about 4 times as many CD4+ T-cells as CD8+ T-cells when analyzed with a FACScan fluorescence analyzer. The composition of the NALT lymphocytes was similar to that of the lymphocytes from the portion of the nasal cavity remaining after isolation of the NALT. The NALT lymphocyte fraction from mice infected 7 days previously with influenza virus was also characterized. The numbers of NALT T- and B-cells from the infected mice were approximately 2 and 3 times higher than those of non-infected mice, respectively. In parallel with the cell increase, NALT lymphocytes produced IFN-gamma when cultured for 24 h and contained cells secreting influenza virus-specific IgA and IgG antibodies. The results suggest that this method can be successfully used for investigating cellular dynamics of mucosal immunology in the upper respiratory tract.

Animals↗
PubMed1997

The immune response following small bowel transplantation. II. A very early cytokine response in the gut-associated lymphoid tissue.

The small bowel has a unique amount of closely associated lymphoid tissue in the form of mesenteric lymph nodes (MLNs) and Peyer's patches (PPs). It is rather unclear how this may affect the immune response to transplants involving small bowel. It is clear, however, that host-derived leukocytes infiltrate this lymphoid tissue very rapidly after transplantation of small bowel, which suggests the possibility of an early immune response within this compartment. To investigate this possibility, we analyzed, using a semiquantitative reverse transcriptase-polymerase chain reaction, the level of cytokine transcripts within isolated MLNs and PPs for the first 7 days after small bowel transplantation. Heterotopic small bowel (n=32) transplants were performed using the following rat strain combinations: syngeneic Lewis (Lew)-->Lew (n=8), blood group D Agouti (DA)-->DA (n=8), allogeneic Lew-->DA (n=8), and allogeneic DA-->Lew (n=8). Two rats from each group were killed at 1, 3, 5, and 7 days after transplantation. RNA was prepared separately from PPs and MLNs before analysis of transcripts for interleukin (IL) 2, IL-4, IL-10, IL-6, IL-1alpha, and interferon (IFN) gamma. No increase in transcripts for IL-2 or IL-10 was observed in either PPs or MLNs of syngeneic grafts. A small rise in IL-6, IL-1alpha, and IFN-gamma transcripts was seen in MLNs and IFN-gamma transcripts in PPs of syngeneic grafts. In contrast, in allografts an extremely early increase in cytokine transcripts was observed; all cytokine transcripts tested were elevated within the first 24 hr after transplantation. Indeed, the peak response of both IL-2 and IL-10 occurred within 1 to 3 days after grafting. This early immune response in the lymphoid tissue may not be controlled by immunosuppression delivered only at the time of transplantation, and therefore may be responsible for the difficulty in achieving adequate immunosuppression in small bowel transplantation.

Animals↗
PubMed1999

Perforin is not co-expressed with granzyme A within cytotoxic granules in CD8 T lymphocytes present in lymphoid tissue during chronic HIV infection.

BACKGROUND: Residual HIV-1-infected cells are poorly eliminated from lymphoid tissue (LT) reservoirs by effector cytotoxic T lymphocytes (eCTL) despite antiretroviral therapy. Perforin and granzyme A (grA) constitute major effector molecules within eCTL granules that induce apoptosis and lysis of virally infected cells. OBJECTIVE: Expression of perforin and grA was studied at the single cell level in LT and blood from 16 patients infected with HIV-1 (stage A1-C) who were not taking antiretroviral therapy. METHOD: Immunohistochemical analysis by in situ imaging of cells from blood and LT. RESULTS: Quantitative in situ imaging showed that perforin-expressing CD8 T cells comprised 0.3-1.5% of total cells within the LT from recent HIV-1 seroconverters, while grA was found in 2.1-7.2% of total cells. However, despite high-level grA upregulation (1.5-4.5% of total cells) compared with that in non-infected individuals (0.4-0.9%), perforin expression remained low (< 0.1% of total cells) (P < 0.02) in LT from patients with chronic HIV-1 infection (stage A2-C). This contrasted with findings in peripheral blood mononuclear cells (PBMC) from the same HIV-1 infected cohort where perforin was detected in 13-31% of all PBMC, which was 10- to 100-fold higher than in lymphoid tissue (P < 0.001); grA was found in 14-32% of total PBMC. Two-colour staining showed that granular expression of perforin and grA was restricted to CD8 T cells in over 90% of total cells in both LT and blood. CONCLUSIONS: These findings indicate that cytotoxic perforin expression is impaired at local sites of HIV replication within lymphoid tissue. Since perforin is required together with grA for granule-mediated cytolysis, the low perforin expression in the LT may limit the ability of eCTL to eliminate HIV-1 infected cells in lymphoid tissue.

CD4 Lymphocyte Count↗
PubMed1999

Changes in macrophage and lymphocyte subpopulations of lymphoid tissues from pigs infected with the porcine reproductive and respiratory syndrome virus (PRRSV).

We used an immunohistochemical method to investigate changes in macrophage and lymphocyte subpopulations in various lymphoid tissues of pigs in the acute phase of porcine reproductive and respiratory syndrome virus (PRRSV) infection. The numbers of CD8+ cells and B-cells varied among lymphoid tissues after PRRSV infection. In the infected pigs, numbers of CD8+ cells increased in systemic lymphoid tissues whereas numbers of B-cells increased in mucosa-associated lymphoid tissues. There was no difference in the distribution of virus-infected cells and macrophages between lymphoid tissues of the infected pigs. These changes may be associated with the establishment of virus persistence or the emergence of concurrent infection in mucosal organs.

Animals↗
PubMed2000

Preclinical diagnosis of scrapie by immunohistochemistry of third eyelid lymphoid tissue.

Ovine scrapie is a member of the transmissible spongiform encephalopathies (TSEs), a heterogeneous family of fatal neurologic disorders characterized by deposition of an abnormal isoform (prion protein [PrP] PrP-Sc) of a cellular sialoglycoprotein in neural tissue. PrP-Sc is detectable in some lymphoid tissues of infected sheep months or years before development of clinical disease. Detection of PrP-Sc in these tissues is the basis for live-animal testing. In this study, we characterize the performance of a preclinical diagnostic test for ovine scrapie based on a monoclonal antibody (MAb)-based immunohistochemistry assay of nictitating membrane ("third eyelid")-associated lymphoid tissue. The results of third eyelid immunohistochemistry assay agreed with the scrapie status of the sheep for 41 of 42 clinical suspects with confirmed scrapie and 174 of 175 sheep without scrapie. Third eyelid sampling agreed with the scrapie status for 36 of 41 clinically normal sheep positive for PrP-Sc immunostaining of brain tissue, including 27 sheep with positive biopsy specimens that progressed to clinical disease with confirmed scrapie 3 to 20 months after biopsy. The assay used MAb F89/160.1.5, which binds to residues 142 to 145 of ovine PrP. This antibody can be used in combination with MAb F99/97. 6.1, which binds to residues 220 to 225. One or both MAbs in this cocktail recognize PrP sequences conserved in most mammalian species in which natural TSEs have been reported. Immunohistochemistry assay of routinely formalin-fixed lymphoid tissues with a cocktail of pan-specific MAbs is a practical, readily standardized live-animal and preclinical test for ovine scrapie.

Animals↗
PubMed2003

Structure, lymphatic vascularization and lymphocyte migration in mucosa-associated lymphoid tissue.

In this review, we consider the morphological aspects and topographical arrangement of gut-associated lymphoid tissue (GALT) (solitary and aggregate lymph nodules or Peyer's patches) and of vermiform appendix in the human child and in some mammals. The spatial arrangement of the vessels belonging to apparatus lymphaticus periphericus absorbens (ALPA) and of blood vessels within each lymphoid follicle as well as the ultrastructural characteristics of the lymphatic endothelium with high absorption capacity are considered. Particular attention is also paid to the morphological and biomolecular mechanisms inducing lymphocyte transendothelial migration to the bloodstream by means of lymphatic vessels as well as their passage from blood into lymphoid tissue through the high endothelial venules (HEVs). The preferential transendothelial passage of lymphocytes and polymorphonuclear neutrophils within ALPA vessels of the interfollicular area does not occur following the opening of intercellular contacts, but rather it occurs by means of 'intraendothelial channels'. In HEVs, on the contrary, the hypothesis is plausible that lymphocyte transendothelial migration into lymphoid tissue occurs through a channel-shaped endothelial invagination entirely independent of interendothelial contacts. The lymph of ALPA vessels of the single Peyer's patch is conveyed into precollector lymphatic vessels and into prelymph nodal collectors, totally independent of the ALPA vessels of the gut segments devoid of lymphoid tissue. The quantitative distribution of T lymphocytes in the lymph of mucosal ALPA vessels suggests a prevalent function of fluid uptake, whereas a reservoir and supply function is implicated for the vessels of interfollicular area. The precollector lymphatic vessels and prelymph nodal collectors are considered to be vessels with low absorption capacity, whose main function is lymph conduction and flow.

Animals↗
PubMed1965

Cellular localization of immunoglobulins with different allotypic specificities in rabbit lymphoid tissues.

The cellular localization of allotypes in rabbit lymphoid tissues has been studied by immunofluorescence. In heterozygous animals the double staining for two allotypes controlled by allelic genes (A1 and A2; A4 and A5; A4 and A6) has shown the existence of two populations of plasma cells, one containing one allotype and the other the alternative one. The localization in different cells of immunoglobulins marked by allelic allotypic specificities has been confirmed by microspectrography of single cells. An exception to this rule was given by the presence in the germinal centers of lymphoid follicles of apparently uniform mixtures of products of the two allelic genes. Double staining for two allotypes controlled by genes at different loci showed, instead, the presence of many cells containing both allotypes; the number of these cells was highest in doubly homozygotes, in the other it was consistent with random association of non-allelic specificities. In addition double staining for one allotype and gamma G globulins in the lymphoid tissues of rabbits homozygous at the a or at the b locus, has shown the presence of cells containing immunoglobulins that lack one allotype.

Animals↗
PubMedDate not supplied

Mucosa-associated lymphoid tissue lymphoma of the extrahepatic bile duct.

Mucosa-associated lymphoid tissue lymphoma of the extrahepatic bile duct has not yet been reported. Much more common than this is secondary involvement of the extrahepatic bile duct in cases of disseminated lymphoma. A 59-year-old man manifesting jaundice was referred to our hospital. PTC revealed an extrahepatic bile duct stenosis from the hilum to the lower part of the choledochus. On the operative specimen, we examined L26/CD20, Bcl-2, UCHL-1/CD45RO, cyclin D1 and p53. Histologically, follicular colonization, centrocyte-like cells and lymphoepithelial lesion was observed. Tumor cells were positive for L26/CD20 and Bcl-2 and were negative for intracytoplasmic immunoglobulins, UCHL-1/CD45RO, cyclin D1 and p53. Pathological diagnosis was mucosa-associated lymphoid tissue lymphoma of the extrahepatic bile duct. The authors present herein the first case of mucosa-associated lymphoid tissue lymphoma of the extrahepatic bile duct. It was very difficult to distinguish from hilar cholangiocarcinoma clinically. Only incomplete stenosis of the bile duct and 18-F fluoro-2-deoxyglucose positron emission tomography (FDG-PET) could suggest this unusual clinical entity.

Antigens, CD20↗
PubMed1999

Mucosa-associated lymphoid tissue lymphoma of the lacrimal gland.

PURPOSE: Mucosa-associated lymphoid tissue lymphoma recently has been defined as a distinct subtype of non-Hodgkin's lymphoma with characteristic clinicopathologic features. A 37-year-old woman with systemic lupus erythematosus and unilateral mucosa-associated lymphoid tissue lymphoma of the lacrimal gland is described. METHODS: The tumor was totally excised by lateral orbitotomy. Immunohistochemical studies were performed with UCHL-1, CD20 (L26), leukocyte common antigen, cytokeratin (CAM5), and kappa and lambda light chain antibodies. RESULTS: The tumor was composed of centrocyte-like lymphocytes, cells with plasmacytoid features, and lymphoepithelial lesions. Most of the cells expressed the CD20 protein and were positive for immunoglobulin kappa light chain. The patient received no supplemental therapy. No systemic dissemination or local recurrence occurred during a follow-up of 26 months. CONCLUSION: The features of this case support the association between systemic diseases and the subsequent development of mucosa-associated lymphoid tissue lymphoma.

Adult↗
PubMed2004

Role of inducible bronchus associated lymphoid tissue (iBALT) in respiratory immunity.

Bronchus-associated lymphoid tissue (BALT) is occasionally found in the lungs of mice and humans; however, its role in respiratory immunity is unknown. Here we show that mice lacking spleen, lymph nodes and Peyer's patches generate unexpectedly robust primary B- and T-cell responses to influenza, which seem to be initiated at sites of induced BALT (iBALT). Areas of iBALT have distinct B-cell follicles and T-cell areas, and support T and B-cell proliferation. The homeostatic chemokines CXCL13 and CCL21 are expressed independently of TNFalpha and lymphotoxin at sites of iBALT formation. In addition, mice with iBALT, but lacking peripheral lymphoid organs, clear influenza infection and survive higher doses of virus than do normal mice, indicating that immune responses generated in iBALT are not only protective, but potentially less pathologic, than systemic immune responses. Thus, iBALT functions as an inducible secondary lymphoid tissue for respiratory immune responses.

Animals↗
PubMed2002

Mucosa-associated lymphoid tissue lymphoma.

Since the first description of mucosa-associated lymphoid tissue (MALT) lymphoma in 1983 rapid advances have been made in the understanding of the pathogenesis and underlying molecular events associated with the development of this tumor. Lymphoma arises at extranodal sites in which a pre-existing inflammatory response has provoked the acquisition of organized lymphoid tissue. Specific molecular events have been associated with the development of MALT lymphoma including t(11;18) and alterations in Bcl-10 protein expression, and these appear to be interlinked. In gastric MALT lymphoma Helicobacter pylori is the most common stimulus for the acquisition of lymphoid tissue. Eradication of this organism has been shown to result in regression of the tumor in many cases, but there are a few that will not respond to this approach. Predicting those cases unlikely to respond to H pylori eradication alone has been investigated in a number of ways. An underlying t(11;18) within the tumor cells appears to predict for a lack of response. Clinical measurement of the depth of infiltration of the wall by gastric MALT lymphoma as measured by endoscopic ultrasound has been less clear. More superficial tumors are more likely to respond, but regression has been reported even in cases with local lymph node involvement. For superficial lymphomas at other sites alternatives to radiotherapy, chemotherapy, or surgery have been sought. Local injections of interferon (IF) alpha have been successful in treating conjunctival lymphoma, and this approach may be of use for other superficial lesions.

Adaptor Proteins, Signal Transducing↗
PubMedDate not supplied

Detection of PrPSc in lymphoid tissues of lambs experimentally exposed to the scrapie agent.

Histoblotting and immunohistochemistry were used to detect disease-associated prion protein (PrP(Sc)) in lymphoid tissues of lambs of known PrP genotype infected with the scrapie agent by stomach tube at the age of 2 months. The ileal and jejunal Peyer's patches and retropharyngeal and distal jejunal lymph nodes were studied 1 week, 5 weeks, 5 months and 11 months after inoculation. Other lymphoid tissues examined included superficial cervical lymph node, tonsil and spleen. PrP(Sc) was not detected in any tissue of any lamb at 1 week post-inoculation. At 5 weeks, PrP(Sc) was detected in tissues of lambs of susceptible PrP genotypes (AV(136)QQ(171) and VV(136)QQ(171)), but not lambs of other PrP genotypes (AA(136)QQ(171), AA(136)QR(171) and AV(136)QR(171)). PrP(Sc) was present in the germinal centres of tonsils, distal jejunal and retropharyngeal lymph nodes, and spleen. In the nodules of ileal and jejunal Peyer's patches, only occasional solitary cells showed the presence of PrP(Sc). At 5 months post-inoculation, increased accumulations of PrP(Sc) were detected in ileal and jejunal Peyer's patches, as well as in the retropharyngeal and distal jejunal lymph nodes of a single lamb inoculated with the agent from a sheep of the same susceptible PrP genotype. Eleven months after exposure to the scrapie agent, PrP(Sc) was detected in all lymphoid tissues examined from sheep of susceptible PrP genotypes. These studies show that PrP(Sc) was detectable in lymphoid tissues 5 weeks after exposure to the scrapie agent by stomach tube in lambs as young as 3 months of age and indicate that the PrP genotype is a significant factor for the rapid uptake and spread of the agent through lymphoid tissues.

Animals↗
PubMed1981

Canine transmissible venereal sarcoma: leukocyte adherence inhibition (LAI) reactivity of various lymphoid tissues of dogs with tumors at different stages of growth.

Leukocyte adherence inhibition (LAI) reactivity of various lymphoid tissues of dogs with canine transmissible venereal sarcoma (CTVS) at different stages of growth was determined by the tube LAI test. Tumors were classified at the time of excision into progressor, steady state, and regressor stages of growth. The LAI reactivity to CTVS antigen extract of spleen, draining and non-draining lymph-node cells, and peripheral blood leukocytes of regressors (non-adherence index--NAI of 172.8 +/- 46.8, 148.1 +/- 64.7, 138.7 +/- 47.3, and 172.2 +/- 60.7, respectively) was significantly greater than that of progressors (46.1 +/- 20.0, 38.5 +/- 21.5, 50.2 +/- 30.0, 24,6 +/- 37.2, respectively, p less than 0.001) and normal dogs (47.5 +/- 22.8, 54.6 +/- 24.6, 26.7 +/- 14.0, 50.9 +/- 22.4, respectively, p less than 0.001). In contrast, LAI reactivity of progressor lymphoid tissues to CTVS antigen extract did not differ significantly from that of normal dogs. LAI reactivity of lymphoid tissues from steady state tumor bearers (97.9 +/- 39.2, 80.7 +/- 47.3, 87.1 +/- 40.0, 85.1 +/- 53,9, respectively) was intermediate between and significantly different from LAI reactivities of regressor (p less than 0.05) and progressor (p less than 0.01) lymphoid tissues. Significant LAI reactivity observed in regressors suggests the presence of a functional effector cell mechanism associated with spontaneous regression of CTVS. The three distinct patterns of LAI reactivity observed in tumor-bearing dogs appear to correlate with the clinical course of tumor growth.

Animals↗
PubMed1985

Lymphomas of the mucosa-associated lymphoid tissue. Signet ring cell lymphomas presenting in mucosal lymphoid organs.

Four cases of lymphoma are reported which were postulate to have developed from neoplastic transformation of the lymphoid cells of the mucosa-associated lymphoid tissue (MALT). This contention is primarily based on two observations: the peculiar "homing" tendency of these lymphomas and the immunoglobulin isotype. Both properties are characteristic of the lymphoid cells of the MALT. These lymphomas can also be identified by their histologic structure (signet ring cell lymphomas) and their presentation in an MALT organ. These lymphomas are probably separable from other lymphomas proposed to arise from lymphocytes of the gut-associated lymphoid system (GALT).

Aged↗
PubMed1994

The arrangement of gut-associated lymphoid tissues and lymph pathways in the koala (Phascolarctos cinereus).

Gut-associated lymphoid tissues are poorly developed in koalas. They comprise paired caecocolic lymphoid patches, and a few small mesenteric lymph nodes. The patches lie opposite one another in the lateral gut wall at the junction of the ileum, caecum and proximal colon. The lymphoid parenchyma of the patches consists of a layer of nodules and internodular parenchyma in the submucosa. Apoptosis is common in the nodules. The mucosa and lymphoid tissue of each patch is continuous over a caecocolic recess, formed by the coalescence of laminae which extend along the large intestine. Lymph sinuses between and beneath the lymphoid nodules are continuous with efferent lymph vessels in the submucosa. These then enter 2-4 small lymph nodes at the root of the mesentery. The paucity of lymphoid tissue associated with the gut may be related to germicidal activity in the Eucalypt leaves eaten by the koala.

Animals↗