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PubMed1988

Gut-associated lymphoid tissue in the large intestine of calves. II. Electron microscopy.

Scanning electron microscopy of lymphoid tissue in the large intestine of three germfree calves (age 3, 6, and 7 days) revealed two different units: propria nodules and lymphoglandular complexes (LGC). Propria nodules had lymphoid tissue predominantly in lamina propria and were covered by distinct follicle-associated epithelium which lacked goblet cells; nodules were surrounded by wide crypts, which were also lined by follicle-associated epithelium towards the luminal side. Lymphoglandular complexes had lymphoid follicles in the tunica submucosa; epithelial diverticulae extended through the muscularis mucosae branching into the lymphoid nodule. In centers of lymphoglandular complexes, protrusions of lymphoid tissue were covered with distinct follicle-associated epithelium. By transmission electron microscopy cells compatible with M cells in the small intestine of calves and cells with characteristics of both enteroabsorptive and M cells were found. Follicle-associated epithelium of propria nodules and lymphoglandular complexes differed only in the relative frequency of cell types.

Animals↗
PubMed1993

Immunohistochemical distribution of leucocyte antigens in lymphoid tissues of cynomolgus monkeys (Macaca fascicularis).

Crossreactivity of antibodies to human leucocyte antigens with lymphoid tissues of cynomolgus monkeys was studied by immunohistochemistry and immunoblotting. Of a total of 54 clusters of differentiation (CD) antigens, 39 were expressed essentially with the same immunostaining patterns in the monkey as in human lymphoid tissues. By immunoblotting L26 (CD20) detected a 35 Kd molecule in the monkey lymph node. Our observations indicated that most of the CD antigens are expressed and can be studied in lymphoid tissues of cynomolgus monkeys.

Animals↗
PubMed1986

The development of gut associated lymphoid tissue in the terminal ileum of fetal human intestine.

Lymphoid tissue in formalin fixed and snap frozen human fetal ileum has been studied using immunohistochemistry. At 11 weeks gestation clusters of cells expressing CD4 (leu-3a positive) are present in fetal ileum but these do not express CD3 (UCHT1 negative) and are probably macrophages. Aggregates of lymphoid tissue are apparent from 14 weeks gestation which contain T cells of helper/inducer and suppressor/cytotoxic phenotype. Both B and T cells are present at 16 weeks but with no cellular zonation. By 19 weeks, distinct follicles of B cells are present surrounded by T cells of helper/inducer and suppressor/cytotoxic phenotype. Follicular dendritic cells are also present within the B cell areas. The B cells at this age express surface IgM and IgD, C3b- and C3d-receptors. They also express the antigen CD5 which has been shown by others to be present on some fetal B cells but which is almost exclusively associated with T cells in the adult. HLA-D region antigens are present on apparently all of the cells within the fetal lymphoid follicles. The antigen on activated B cells, CD23 (recognized by MHM6), was present on some cells scattered within the B cell follicle. This is indicative of antigen independent B cell proliferation.

B-Lymphocytes↗
PubMed1993

Distribution of T cell subsets in chicken lymphoid tissues.

The distributions of T cell subsets in chicken lymphoid tissues were investigated immunohistochemically using monoclonal antibodies (Lc-6, Lc-4) with specificity for chicken CD4 and CD8, respectively. In thymic tissues, CD8+ cells were found only in the cortex, while CD4+ cells were detected not only in the cortex but also in the medulla. The cortex just below the capsule demonstrated no immunoreactivity to either antibody. In the cecal tonsile, CD8+ cells were found restrictly in the subepithelial lamina propria. It was noted that the germinal centers were clearly surrounded with many CD4+ cells in the mid and deep portions of the lamina propria. In the spleen, clusters of CD8+ cells were observed only in the red pulp. Most lymphocytes in the periarteriolar lymphatic tissue and perivenous lymphatic tissue showed a CD4-positive reaction. No lymphocyte in the germinal centers reacted with these two monoclonal antibodies. No immunoreactivity for either CD8 or CD4 was detected anywhere else in the bone marrow or bursa of Fabricius. In the case of exposure to the protein antigen (alum-precipitated bovine serum albumin), CD4+ cells were demonstrated in some germinal centers, which were increased in size, while the areas expressing CD8 in the red pulp were decreased in size. These results suggest that the preferential distributions of T cell subsets are inherent in chicken lymphoid tissues.

Animals↗
PubMed2003

Involvement of the chromosomal translocation t(11;18) in some mucosa-associated lymphoid tissue lymphomas and diffuse large B-cell lymphomas of the ocular adnexa: evidence from multiplex reverse transcriptase-polymerase chain reaction and fluorescence in situ hybridization on using formalin-fixed, paraffin-embedded specimens.

The chromosomal translocation t(11;18) is a unique chromosomal aberration associated with mucosa-associated lymphoid tissue lymphoma. API2 and MALT1 genes have been identified around this translocation. We attempted to find chromosomal abnormalities focusing mainly on the t(11;18) translocation in formalin-fixed, paraffin-embedded tissues of ocular adnexal lymphoproliferative disorders using multiplex reverse transcriptase-polymerase chain reaction and/or two-color interphase fluorescence in situ hybridization. By these methods, the t(11;18) translocation was detected in 1 of 8 patients with reactive lymphoid hyperplasia (13%), 3 of 23 with mucosa-associated lymphoid tissue lymphoma (13%), and 2 of 14 with diffuse large B-cell lymphoma with/without mucosa-associated lymphoid tissue lymphoma (14%). Moreover, we performed fluorescence in situ hybridization analysis to detect any numerical aberration of chromosomes 3, 7, 12, and 18 on some specimens nonselectively. No numerical chromosomal abnormalities were detected in 3 cases of reactive lymphoid hyperplasia, whereas three of four cases of mucosa-associated lymphoid tissue lymphoma and all four cases of diffuse large B-cell lymphoma with/without mucosa-associated lymphoid tissue lymphoma components exhibited one or more abnormalities. These findings indicate a possibility that at least in the ocular adnexa, some diffuse large B-cell lymphomas are derived from mucosa-associated lymphoid tissue lymphomas.

Adult↗
PubMed1987

Gut-associated lymphoid tissue as source of an IgA immune response in respiratory tissues after oral immunization and intrabronchial challenge.

Most IgA plasma cells in the digestive tract are thought to derive from gut-associated lymphoid tissue, whereas IgA plasma cells in the respiratory mucosa are thought to originate largely in bronchus-associated lymphoid tissue. However, previous work has also shown that IgA antibodies to gut antigens can be detected in immunocytes of the bronchial mucosa and in bronchial secretions after appropriate stimulation via the gut. To analyze the cellular origin of such respiratory antibodies, mice were orally immunized with ferritin for 40 days and then segregated for intrabronchial challenge as follows: one group was given saline, another group Formalin-fixed Escherichia coli as a nonspecific challenge, and a third group ferritin. Lungs and intestines from these animals were then examined by immunofluorescence for the presence of plasma cells containing particular isotypes of antibody to ferritin. Animals fed ferritin and given saline or E. coli intrabronchially showed a greater than 6-fold increment in IgA antiferritin plasma cells in the bronchial mucosa, compared to animals which had not received ferritin, whereas orally immunized animals challenged intrabronchially with ferritin showed a greater than 15-fold increase. In other experiments, ferritin-naive animals transfused with mesenteric node cells that were obtained from donors that had been orally immunized with ferritin and were already committed to IgA production showed a 4-fold or greater increase in IgA antiferritin plasma cells in respiratory mucosa after intrabronchial challenge with ferritin when compared to recipients of peripheral node cells from the same donors or to recipients of mesenteric node cells that had not been specifically boosted intrabronchially. These results suggest that immunologically specific IgA immunocytes from gut-associated lymphoid tissue can migrate to the respiratory mucosa after oral immunization, and that migration and/or local cell division are enhanced by subsequent intrabronchial challenge. In providing further evidence for interrelations between gut-associated and bronchus-associated lymphoid tissue, the findings lend added support to the overall concept of a generalized secretory immune system.

Administration, Oral↗
PubMed1984

Human antigen-specific IgA responses in blood and secondary lymphoid tissue: an analysis of help and suppression.

Antigen-specific IgA responses to influenza virus were obtained from lymphocytes derived from human secondary lymphoid tissue but not from the circulating pool (blood). T helper cells for IgA were present in both the circulating pool and secondary lymphoid tissue, were of the Leu-3A+ subset, and were relatively radioresistant. In addition, T alpha cells were shown to be important, but not crucial, for IgA helper responses. T cell-dependent suppression of IgA responses was demonstrated with T cells from both mucosal and systemic lymphoid tissue and was mediated by a radiosensitive Leu-2a+ cell. In contrast to T cells, functional B cell precursors for antigen-specific IgA responses were found only in secondary lymphoid tissue and not in the circulating pool.

Antibodies, Viral↗
PubMed2004

Regression of rectal mucosa-associated lymphoid tissue lymphoma but persistence of Helicobacter pylori infection of gastric mucosa after administration of levofloxacin: report of a case.

PURPOSE: Several articles have reported regression of rectal lymphoma of mucosa-associated lymphoid tissue after anti- Helicobacter pylori therapy. It remains unclear, however, whether lymphoma of rectal mucosa-associated lymphoid tissue is related to Helicobacter pylori infection. METHODS: A 60-year-old woman visited our hospital with a complaint of hematochezia. On colonoscopy a pale, ulcerated protrusion approximately 3.5 cm in diameter was found in the rectum. Pathologic diagnosis of a biopsy specimen was low-grade mucosa-associated lymphoid tissue lymphoma. The patient received a ten-day course of levofloxacin, and the cycle was repeated three times over seven months. RESULTS: Although persistence of Helicobacter pylori infection was confirmed, the tumor regressed completely. CONCLUSION: Our findings in this case suggest that rectal lymphoma of mucosa-associated lymphoid tissue may be related to unknown microorganisms other than Helicobacter pylori. Levofloxacin may be effective for treatment of rectal lymphoma of mucosa-associated lymphoid tissue regardless of Helicobacter pylori infection.

Anti-Infective Agents↗
PubMed2004

Histological studies on the ontogeny of bovine gut-associated lymphoid tissue: appearance of T cells and development of IgG+ and IgA+ cells in lymphoid follicles.

The development and distribution of lymphocyte subsets in bovine gut-associated lymphoid tissues (ileal and jejunal Peyer's patches (PP)) were examined. Before birth, the composition of lymphocyte subsets in both PP follicles did not differ except for the dimensions of the interfollicular area and the dome region. Many IgM+ cells were observed in these follicles, but very few CD3+, IgG+, and IgA+ cells could be found. At neonatal period, the IgG+ cells, which did not produce IgG mRNA, were dominant within both PP follicles. From 1 month after birth, many CD3+ cells, IgG mRNA expression, and IgA mRNA expression were detected within the jejunal PP follicles, but very few were in the ileal PP follicles. These data suggest that the characteristics of the jejunal PP follicles metamorphose into secondary lymphoid tissue such as germinal centers at around 1 month after birth, whereas the characteristics of ileal PP follicles were distinct from those of germinal centers.

Animals↗
PubMed1988

The effect of dietary lipid hydroperoxide on lymphoid tissues in mice.

Effects of dietary lipid hydroperoxides on lymphoid tissue were studied in mice. When graded amounts (190, 270 and 310 mg) of methyl linoleate hydroperoxide (MLHPO) were orally administered to male C57BL/6 mice (6 weeks old), necrosis was observed in lymphocytes located among the reticular network in the thymus, and thymus weight was significantly decreased 24 h after the treatment. The spleen weight of mice given MLHPO tended to decrease. Spontaneous chemiluminescence of the thymus was remarkably increased after the dose. Thiobarbituric acid reactants in the liver, thymus and blood were also increased after the dose of MLHPO. At intervals of 3, 6, 12 and 24 h after a dose of 14C-labeled MLHPO, 14C was detected in the blood and liver. Fatty infiltration of the liver was found after the treatment with MLHPO. These findings indicate that oral intake of lipid hydroperoxides causes significant damage to lymphoid tissues of mice.

Administration, Oral↗
PubMed1994

Functional studies on MEL-14+ and MEL-14- T cells in peripheral lymphoid tissues.

Functions of MEL-14+ T cells and MEL-14- T cells in peripheral lymphoid tissues were analyzed and compared. The MEL-14- T cells, representing a minor subpopulation of spleen and lymph node T cells, generated considerably higher mixed lymphocyte reaction and mitogen responses than the MEL-14+ T cells in any lymphoid tissues studied. Furthermore, upon stimulation with ConA the MEL-14- CD8+ T cells produced significantly larger amounts of IL-2 and IFN-gamma than MEL-14+ CD8+ T cells did. A similar but less marked observation was obtained with the CD4+ T cell population. Furthermore, when B10.BR mice were immunized with AKR (Mls-1a) spleen cells, the proportion of the Mls-1a reactive V beta 6+ T cells from draining lymph nodes increased and a substantial proportion of the increasing V beta 6+ T cells was shown to be MEL-14-. The present findings on the whole indicate that MEL-14- T cells in the peripheral lymphoid tissues are at functionally high levels and may represent memory cells which have been previously stimulated in vivo.

Animals↗
PubMed1999

Preferential coreceptor utilization and cytopathicity by dual-tropic HIV-1 in human lymphoid tissue ex vivo.

Many HIV-1 isolates at the late stage of disease are capable of using both CXCR4 and CCR5 in transfected cell lines, and are thus termed dual-tropic. Here we asked whether these dual-tropic variants also use both coreceptors for productive infection in a natural human lymphoid tissue microenvironment, and whether use of a particular coreceptor is associated with viral cytopathicity. We used 3 cloned dual-tropic HIV-1 variants, 89.6 and its chimeras 89-v345.SF and 89-v345.FL, which use both CCR5 and CXCR4 in transfected cell lines. In human lymphoid tissue ex vivo, one variant preferentially used CCR5, another preferentially used CXCR4, and a third appeared to be a true dual-tropic variant. The 2 latter variants severely depleted CD4(+) T cells, whereas cytopathicity of the virus that used CCR5 only in lymphoid tissue was mild and confined to CCR5(+)/CD4(+) T cells. Thus, (a) HIV-1 coreceptor usage in vitro cannot be unconditionally extrapolated to natural microenvironment of human lymphoid tissue; (b) dual-tropic viruses are not homogeneous in their coreceptor usage in lymphoid tissue, but probably comprise a continuum between the 2 polar variants that use CXCR4 or CCR5 exclusively; and (c) cytopathicity toward the general CD4(+) T cell population in lymphoid tissue is associated with the use of CXCR4.

Anti-HIV Agents↗
PubMed1986

Expression of HLA-DR antigens on epithelium associated with lymphoid tissue in the human gastrointestinal tract.

Mucosa from human stomach, terminal ileum, appendix, and colon was studied for epithelial HLA-DR expression using an immunoperoxidase technique with a monoclonal antibody that detects HLA-DR antigens in paraffin embedded tissues. Expression of HLA-DR by epithelial cells was studied with particular reference to the effect of adjacent lymphoid tissue or surrounding chronic inflammation. In the stomach, epithelial HLA-DR appeared to be induced by chronic inflammation. Where lymphoid nodules were present only that epithelium directly adjacent to the lymphoid tissue expressed HLA-DR. Expression was independent of cell type. Epithelium adjacent to normal lymphoid tissue in the terminal ileum, appendix, and colon also expressed HLA-DR, the relationship between expression and proximity to lymphoid tissue being remarkably precise. Expression of HLA-DR by gastrointestinal epithelium appears to be an effect of adjacent lymphocytes, whether part of an inflammatory response or normal tissue. This must be taken into account when assessing HLA-DR expression by gastrointestinal epithelium.

Appendix↗
PubMed2004

IgA class switch occurs in the organized nasopharynx- and gut-associated lymphoid tissue, but not in the diffuse lamina propria of airways and gut.

Secretory IgA plays a crucial role in the host immune response as a first line of defense. A recent demonstration of in situ IgA class switching in intestinal lamina propria provided an opportunity to reconsider the model for the homing of IgA-committed B cells characterized by distinctive trafficking patterns to effector sites. Those effector sites depend on the organized mucosa-associated lymphoid tissues as their site of induction. In this report we show the preferential presence of IgM(+)B220(+) and IgA(+)B220(+) cells belonging to pre- and post-IgA isotype class-switched cells in the organized mucosa-associated lymphoid tissues, such as nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches, and the defect of those populations in the diffuse effector tissues, such as the nasal passage and intestinal lamina propria. Consistent with these findings, the expressions of a series of IgA isotype class switch recombination-related molecules, including activation-induced cytidine deaminase, Ialpha-C micro circle transcripts, and Ialpha-C micro circle transcripts, were selectively detected in these organized mucosa-associated lymphoid structures, but not in the diffuse mucosal effector sites. Taken together, these findings suggest that IgA isotype class switching occurs only in the organized mucosa-associated lymphoid organs (e.g., nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches), but not in the diffuse effector tissues of the upper respiratory and gastrointestinal tracts.

Animals↗
PubMed1978

Immunology of the lower respiratory tract. III. Concentrations of antigen and of antibody-forming cells in pulmonary and systemic lymphoid tissues of dogs after intrapulmonary or intravenous administration of sheep erythrocytes.

The distribution of antibody-forming cells to sheep erythrocytes among canine pulmonary and systemic lymphoid tissues differs distinctively depending on whether antigen is administered by the intrapulmonary or the intravenous (i.v.) route. After local (intrapulmonary) immunization, antibody-forming cells are restricted to the lung and regional lymph nodes; after i.v., they are widespread. To test the hypothesis that the tissue distribution of antigen is an important determinant of the resultant distribution of antibody-forming cells, dogs were immunized with radioiodinated sheep erythrocytes, either intrapulmonary (i.p.) or i.v. After 4 days, the concentrations of tissue-bound radioactivity and of antibody-forming cells in various lymphoid tissues were compared. The distribution of tissue-bound radioactivity among lymphoid tissues was clearly determined and different depending on the route of immunization. After i.p. administration, radioactivity was bound to lung and hilar lymph nodes; after i.v., it was found in the lung, liver, spleen and occasionally hilar nodes. Antibody-forming cells appeared in those lymphoid preparations which contained tissue-bound radioactivity. The exception was that locally applied antigen elicited antibody-forming cells in the lung poorly, despite the fact that abundant antigen remained localized to the lung. Notably, i.v. immunization resulted in the appearance of both antibody forming cells and cell-bound radioactivity in the lung. It is concluded that the distribution of antigen among tissues is a major determinant of the distinctive patterns of appearance of antibody-forming cells after different routes of immunization.

Animals↗
PubMed1998

Oral administration of the bacterial superantigen staphylococcal enterotoxin B induces activation and cytokine production by T cells in murine gut-associated lymphoid tissue.

The toxicity of the staphylococcal enterotoxins (SEs) has been linked to the activation of large numbers of T cells in the peripheral lymphoid tissues. Because the primary manifestations of foodborne enterotoxic poisoning are associated with the gastrointestinal tract, we have compared the responses of T cells in the gut-associated lymphoid tissue and in the periphery to intragastric (i.g.) and i.p. administration of SEB. Intraperitoneal SEB results in an early expansion of peripheral Vbeta8+ T cells and Th1 cytokine secretion followed by deletion at 7-10 days. We found that i.g. SEB rapidly (within 4 h) leads to the expansion and activation of Vbeta8+ T cells in the Peyer's patch and mesenteric lymph nodes. Analysis of cytokine mRNA in purified Vbeta8+ T cells by competitive RT-PCR showed that, 4 h after i.g. SEB, the induction of mRNA for IL-2 and IFN-gamma is about 10-fold greater in mucosal than in peripheral lymphoid tissue. Our results show that activated mucosal T cells expand and up-regulate cytokine mRNA in response to luminal exposure to SEB, suggesting a role for the gut-associated lymphoid tissue in the gastrointestinal manifestations of enterotoxic poisoning.

Administration, Oral↗
PubMed2000

Evidence of M cells as portals of entry for antigens in the nasopharyngeal lymphoid tissue of humans.

The nasopharyngeal tonsils (adenoids) are prominent components of human nasal-associated lymphoid tissues (NALT). However, the role of the nasopharyngeal tonsils in antigen uptake for initiation of the mucosal immune response is unknown. The aims of this study were to describe the ultrastructure and function of the M cells of the human nasopharyngeal tonsils and to clarify their capacity for antigen uptake. Tissues obtained from eight patients undergoing adenectomy were examined by light and electron microscopy. Lymphoepithelium covers the nasopharyngeal lymphoid tissue and consists of ciliary epithelium, non-ciliary epithelial cells, M cells, goblet cells, and many intraepithelial lymphoid cells. M cells have irregular and broad cytoplasm-containing microvilli on their surface and small vesicles in their cytoplasm. Many lymphoid cells were enfolded by M cells. The uptake of horseradish peroxidase (HRP) in the tissue in organ culture was studied using histochemical techniques. Excised adenoid tissue was incubated in RPMI 1640 culture media with HRP for 10, 30, and 60 min. HRP which had adhered to the surface was taken up in vesicles and then transported in vesicles and tubules by M cells. The M cells of nasopharyngeal lymphoid tissue were ultrastructurally and functionally similar to those in human Peyer's patches and colonic lymphoid follicles. These findings indicate that NALT bears similarities to the gut-associated lymphoid tissue, and its antigen uptake capacity may be important for initiation of immunity in the upper aerodigestive tract.

Adenoidectomy↗