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PubMed1976

[Lymphoid tissue and the body's non-specific resistance].

In experiments on rats and mice the author and his pupils showed that nonspecific effect of stimulators brought about in the first hours following the exposure migration of cells from the lymphoid organs, increase in the number of lymphoid cells in the bone marrow by 40-60%, appearance in the bone marrow of T-cells, and increase in the number of hemopoietic cells (CFU). This contributed to the activation of hemopoiesis and to development of transient hyperplasia of the bone marrow to the stage of elevated resistance of the organism. It was shown that transplantation of T-cells performed in the first hours after the sublethal irradiation hastened regeneration of hemopoiesis. All the data indicated above testify to the role of the lymphoid tissue in nonspecific resistance of the organism.

Animals↗
PubMed2000

Lectin binding patterns in rat nasal-associated lymphoid tissue (NALT) and the influence of various types of lectin on particle uptake in NALT.

We investigated the binding of four types of lectin to follicle-associated epithelium overlying the nasal-associated lymphoid tissue (NALT) of rats in order to identify M-cell specific surface markers and to determine the influence of lectin administration to NALT on the uptake of a particulate antigen. The NALT tissues were incubated with a panel of four types of lectin conjugated to horseradish peroxidase (HRP). Ulex europaeus-1 (UEA-1) and Dolichos biflorus (DBA) lectin stained the surface of M-cells and goblet cells. Uniform staining by Triticum vulgaris (WGA) was detected in the M-cells, ciliated cells and goblet cells. In contrast, staining of Griffonia simplicifolia I isolectin-B4 (GSI-B4) was almost exclusively M-cell specific. The administration of M-cell specific lectin (GS I-B4) to NALT suppressed the uptake of baker's yeast particles administered later, whereas the non-specific one (UEA-1) had no influence on the uptake. These results indicate that GS I-B4 is a useful marker for the identification of rat NALT M-cells and that such a specific expression of surface glycoconjugates by M-cells may permit the targeting of vaccines and drugs to the antigen sampling sites of the nose. It also appears possible to block the uptake of pathogens by an administration of M-cell specific lectin to NALT.

Animals↗
PubMed1999

The effects of dexamethasone on the response of bronchus-associated lymphoid tissue to intranasal administration of formalin-killed Pasteurella haemolytica A2 in goats.

A trial was conducted to observe the immediate and chronic effects in goats of dexamethasone administration on the bronchus-associated lymphoid tissue (BALT) response to intranasal administration of formalin-killed Pasteurella haemolytica A2. Twenty-four goats were divided into four groups. Those in group 1 were injected intramuscularly with 1 mg/kg dexamethasone on three consecutive days, followed by intranasal exposure to formalin-killed P. haemolytica A2 one day after the last dexamethasone treatment. The goats in group 2 were similarly injected with dexamethasone followed by intranasal exposure to formalin-killed P. haemolytica A2 21 days after the last dexamethasone treatment. The animals in group 3 were exposed intranasally to formalin-killed P. haemolytica A2 without prior dexamethasone treatment. The animals in group 4 were untreated controls. The intranasal exposures to formalin-killed P. haemolytica A2 were repeated 2 weeks later. Intranasal exposure to formalin-killed P. haemolytica 1 day after dexamethasone treatment further reduced the number and size of BALT compared to the untreated control. Significantly (p < 0.01) more reduction of BALT occurred in goats exposed to formalin-killed P. haemolytica A2 21 days after dexamethasone treatment. On the other hand, intranasal exposure of goats without prior dexamethasone treatment stimulated the BALT compared to the untreated controls.

Administration, Intranasal↗
PubMed1994

Feline lymphoid tissues engrafted into scid mice maintain morphologic structure and produce feline immunoglobulin.

To adapt the feline immune system to a small laboratory animal host, severe combined immunodeficient (scid) mice were engrafted with neonatal feline lymphoid tissues, including lymph node, thymus, spleen, and bone marrow. Lymph node and thymus tissue were implanted subcutaneously within the mammary fat pad, and a single-cell suspension of spleen, thymus, and bone marrow was inoculated intraperitoneally (IP). Seven groups of mice (three mice per group) were engrafted on day 0, and members of one group were euthanatized weekly from 2 to 8 weeks after engraftment. For each mouse, graft morphology was evaluated by light microscopy, feline DNA was detected in peripheral blood by polymerase chain reaction (PCR) amplification of feline-specific DNA sequences, and serum IgG concentration was measured by ELISA. Ten of 13 feline grafts evaluated histologically between 3 and 8 weeks after engraftment contained large focal aggregates of lymphocytes bordered by plasma cells. Of 14 thymus grafts evaluated histologically during the same period, 5 were characterized by dense accumulations of small lymphocytes surrounding thymic epithelial cells. Two of these thymus grafts were indistinguishable from age-matched feline thymus. At 2 weeks after engraftment, feline lymph node and thymus contained extensive central necrosis bordered by a narrow zone of lymphocytes and small-caliber blood vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

Hypertrophy, hyperplasia, and infectious virus in gut-associated lymphoid tissue of mice after oral inoculation with simian-human or bovine-human reassortant rotaviruses.

Oral inoculation of infants with a vaccine that contains simian-human reassortant rotaviruses has been found to be a rare cause of intussusception. Because intussusception can be associated with enlargement of gut-associated lymphoid tissue, we studied the capacity of simian-human and bovine-human reassortant rotaviruses to cause lymphoid hypertrophy and hyperplasia of Peyer's patches (PP) of adult BALB/c mice. Neither hypertrophy nor hyperplasia was detected in PP after oral inoculation with simian-human or bovine-human reassortant rotaviruses. However, infectious virus was detected in PP and mesenteric lymph nodes after oral inoculation with simian, but not bovine, reassortant rotaviruses. Implications of these findings on the pathogenesis of intussusception are discussed.

Administration, Oral↗
PubMed2001

CD5 expression in a lymphoma of the mucosa-associated lymphoid tissue (MALT)-type as a marker for early dissemination and aggressive clinical behaviour.

Mucosa associated lymphoid tissue (MALT) developing in response to chronic infection or autoimmune stimuli has been recognized as a possible site of origin for a distinct type of B-cell lymphoma. While preferentially occurring in the stomach, MALT-type lymphomas can be found in virtually all organs. MALT-type lymphomas normally follow an indolent course, with a tendency to remain localized at their site of origin for a prolonged period of time. Histologically, MALT-type lymphomas are heterogeneous covering a cytological spectrum ranging from centrocyte-like cells to smaller lymphoid cells or monocytoid B-cells. Usually a small number of transformed blasts are also present. Immunohistochemically, the malignant cells express markers of B-cell lineage, but are distinct from follicular lymphomas (which express CD10), mantle cell lymphomas (expressing cyclin D1 and CD5) and small lymphocytic lymphoma, which express CD5 and CD23. In contrast to the usual phenotype CD20+CD10-CD5-Cyclin D1-, scattered reports in the literature have documented expression of CD5 in marginal zone B-cell lymphomas of MALT-type. However, these cases are rare, and aberrant CD5-expression has been thought to be a marker for early dissemination and aggressive behavior in some patients, while other reports have also found CD5 expression in localized indolent MALT-type lymphomas. We report a patient with a CD5+ MALT-type lymphoma following an aggressive clinical course without histological progression who relapsed only 18 months after local radiotherapy at the initial localizations (conjunctiva of the right upper eye lid and hypopharynx), and showed a rapid generalization to the contralateral conjunctiva, mediastinal lymph nodes and the esophagogastric junction. Our case lends further support to the notion that CD5+ MALT-lymphomas arising in the head-and-neck area and/or the ocular adnexa might be characterised by an aggressive clinical course.

Aged↗
PubMed2003

A case of mucosa-associated lymphoid tissue lymphoma of the ampulla of Vater: successful treatment with radiation therapy.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the papilla of Vater is rare, and little is known of either its association with Helicobacter pylori infection or the optimal treatment modalities. We describe the first case of MALT lymphoma involving the major papilla that remained unchanged despite eradication of H. pylori, but which regressed following radiotherapy. A 46-year-old asymptomatic man was admitted to hospital for treatment of MALT lymphoma involving the papilla of Vater. Duodenal endoscopy showed multiple granules around the major ampulla, and biopsies revealed mucosal proliferation of centrocyte-like cells, lymphoepithelial lesions, hyperplastic lymphoid follicles and plasmacytic differentiation. The lymphoma cells were positive for B-cell but negative for T-cell markers, and expressed Bcl-2 but showed no immunoreactivity for CD5, CD10 and cyclin D, consistent with MALT lymphoma. The patient was successfully treated with triple therapy of lansoprazole, amoxicillin and clarithromycin for 1 week for coexisting H. pylori infection in the stomach, but the lymphoma lesions remained unchanged. Then, involved-field irradiation was applied at a total dose of 30 Gy delivered in 1.5 Gy fractions without any adverse events. Six months later, repeat endoscopy revealed disappearance of the granular lesions and lack of lymphoma cells in biopsy specimens. Four years after the commencement of radiotherapy, the patient is still in complete remission. Radiotherapy seems a safe and effective treatment modality for low-grade MALT lymphoma of the ampulla of Vater.

Ampulla of Vater↗
PubMed2000

Detection of clonally restricted immunoglobulin heavy chain gene rearrangements in normal and lesional skin: analysis of the B cell component of the skin-associated lymphoid tissue and implications for the molecular diagnosis of cutaneous B cell lymphomas.

A monoclonal B cell population is the hallmark of B cell neoplasms including cutaneous B cell lymphomas (CBCLs). We modified and tested several polymerase chain reaction (PCR)-based assays involving amplification of immunoglobulin heavy chain (IgH) gene rearrangements to optimize assays specifically for cutaneous lymphoid infiltrates. We achieved greatest sensitivity with an assay employing IgH consensus primers complementary to the framework 3 portion of the upstream variable region and the downstream joining region. We studied 12 CBCLs, 6 nodal lymphomas and 7 cell lines. In 17/25 of these B cell neoplasms (84%), we detected one or two dominant bands, consistent with one or both IgH alleles being rearranged in the neoplastic B cell clone. As expected, IgH PCR assays produced diffuse smears in agarose gels or complex ladders in polyacrylamide gels when polyclonal B cell controls (blood and tonsil) were analyzed. However, in normal skin and non-CBCL skin lesions, one or a small number of discrete bands were sometimes detected. In certain cases, this made it difficult to distinguish true positives (monoclonal CBCL) from false positives (clonally restricted benign B cells). Correlation with immunophenotyping confirmed that false positive results were confined to samples with sparse or immunohistologically undetectable B cell infiltrates. Pseudoclonal bands showed variable sizes in repeat PCR reactions and could be distinguished from monoclonal bands by polyacrylamide gel electrophoresis of pooled triplicate PCR products. These findings suggest that molecular diagnosis using IgH PCR assays is best suited for B-cell-rich infiltrates, and can be problematic when applied to suspected T-cell-rich CBCLs, cutaneous T cell lymphomas, or other lesions containing only few B cells unless one is cognizant of the potential pitfalls. Furthermore, these results demonstrate the presence of rare B cells in normal skin and immunohistologically defined cutaneous T cell infiltrates. This correlates with recent reports of sparse B cells within the lymph draining from normal skin and may represent molecular evidence for a trafficking B cell component of the skin-associated lymphoid tissue (SALT). It also suggests a candidate B cell subset for the pathogenesis of cutaneous lymphoid hyperplasia and CBCLs.

B-Lymphocytes↗
PubMed1979

Distribution of Ia-antigen-like molecules on non-lymphoid tissues.

Ia-antigen-like molecules are expressed on cells within several different non-lymphoid tissues of the guinea-pig. In indirect immunofluorescence analyses anti-Ia-antigen antibodies stained epithelial cells lining the intestinal tract, the bile ducts, the respiratory tract and the urinary tract. The rabbit antibodies against Ia antigens also stained the cells of the parotid and the submandibular glands. Evidence was also obtained suggesting that the reticuloepithelial cells of the thymus, like the Kupffer cells of the liver, express Ia-antigen-like molecules. In several cases indirect immunoprecipitation analyses and SDS-polyacrylamide gel electrophoresis confirmed the immunofluorescence studies inasmuch as Ia-antigen-like subunits with apparent molecular weights of 26,000 and 34,000 could be isolated from the non-lymphoid organs.

Animals↗
PubMed1996

Sequence analysis of immunoglobulin variable region genes that encode autoantibodies expressed by lymphomas of mucosa associated lymphoid tissue.

Aim-To determine whether the immunoglobulin genes used by three gastric mucosa associated lymphoid tissue type lymphomas with known autoreactivity are mutated from germline as mutation from germline is an indicator of exposure to a mutational mechanism which characteristically acts on B cells as they undergo a follicle centre response.Methods-Cell lines established from two cases of MALT type lymphoma secrete autoantibodies recognising follicular dendritic cells (one case) and basement membrane (one case). The immunoglobulin heavy chain variable region genes (IgV(H)) and light chain variable region genes (IgV(L)) used by these cell lines, and the IgV(H) genes from a third case recognising human IgG were sequenced.Results-All three cases studied had mutated IgV(H) genes, while the IgV(L) genes were unmutated.Conclusion-The presence of mutations in IgV(H) genes is consistent with the origin of gastric MALT type lymphomas from B cells which have traversed the lymphoid follicle.

Journal Article↗
PubMed2002

Accumulation of DC-SIGN+CD40+ dendritic cells with reduced CD80 and CD86 expression in lymphoid tissue during acute HIV-1 infection.

BACKGROUND: Dendritic cells (DC) are target cells for HIV-1 and play a key role in antigen presentation and activation of T cells. OBJECTIVE: To characterize interdigitating DC in lymphoid tissue (LT) with regard to maturation, expression of cytokines and co-stimulatory molecules in HIV-1-positive patients. METHODS: DC were characterized by immunohistochemistry and in situ imaging in LT from patients with acute HIV-1 infection (aHI), antiretroviral treated patients, long-term non-progressors/slow progressors with HIV-1 infection (LTNP/SLP), patients with AIDS, HIV-1-negative controls and patients with acute Epstein-Barr virus (EBV) infection. RESULTS: A significant increase of interdigitating DC expressing CD1a, S-100b, CD83 and DC-SIGN was found in LT from patients with aHI (P < 0.02). The co-stimulatory molecules CD80 and CD86 were, however, only partially upregulated and the complete parafollicular network found in acute EBV infection was not generated, despite increased expression of interleukins 1alpha, 1beta, 12; interleukin 1alpha receptor antagonist; interferon alpha; and CD40 expression. LTNP/SLP and treated aviremic subjects had increased frequency of interdigitating DC, albeit lower than in aHI, and low expression of CD80 and CD86. In contrast, patients with AIDS had fewer DC and reduced cytokine expression in LT. CONCLUSIONS: In the early phase of HIV-1 infection, there was a migration of DC to LT comparable to that found in acute EBV infection. The infiltration of DC in LT in acute EBV infection was accompanied by upregulation of CD80 and CD86 expression, which did not occur in aHI. This co-stimulatory defect in aHI may have an impact on the development of HIV-1-specific T cell immunity.

Acute Disease↗
PubMed1991

Monocytoid B-cell lymphoma: morphological variants and relationship to low-grade B-cell lymphoma of the mucosa-associated lymphoid tissue.

Twenty-eight cases of monocytoid B-cell lymphoma of lymph nodes and 16 lymph node metastases of primary gastric lymphomas, mostly low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) type were investigated morphologically and immunohistochemically. Both groups showed the same morphological and immunohistochemical features: diagnostically important sites of infiltration were the sinuses and the marginal zones. The tumour cells were either medium-sized or small. The cytoplasm stained grey with Giemsa and was sometimes rather pale. In imprints the grey colour of the cytoplasm was a characteristic feature. The medium-sized cell type was more frequent; in one third of the cases it was combined with a prominent lymphoplasmacytic component from the same clone, and it resembled the monocytoid B-cells of the sinuses. The small cell type was less common, was not combined with a lymphoplasmacytic component and more closely resembled marginal zone cells. The difference was underlined by the negative reaction with the monoclonal antibody Ki-B3 in the small cell type, which, conversely, was positive in the medium-sized cell type and in the monocytoid B-cell reaction of the sinuses. Both of these cell types, however, showed a granular reaction with the new monoclonal antibody Ki-Mlp. The morphological and immunohistochemical parallels are arguments in favour of the assumption that monocytoid B-cell lymphoma is the nodal equivalent of low-grade B-cell lymphoma of MALT type. This is further supported by the fact that in nine of our 28 cases of monocytoid B-cell lymphoma, lymphomas were found simultaneously or subsequently in organs of the MALT. Monocytoid B-cell lymphoma must be differentiated from an infiltration that occurs in the form of clusters of monocytoid B-cells in other low-grade B-cell lymphomas, especially in immunocytoma with a high content of epithelioid cells.

Adult↗
PubMedDate not supplied

Effects of modified-live infectious bronchitis virus vaccines on the head-associated lymphoid tissue (HALT).

Specific-pathogen-free (SPF) leghorn chicks were inoculated with different modified-live infectious bronchitis virus (IBV) vaccines to determine if the vaccines interfered with immune competence of the head region. A total of 16 vaccines were evaluated comprising nine Massachusetts, three Arkansas, two Holland, one Florida, and one combination vaccine (containing both Connecticut and Massachusetts). Chicks were vaccinated when they were 4 weeks, 2 weeks, or 1 day of age. When all chickens were 4 weeks 3 days of age, their glands of Harder (GH) were assayed for the ability to respond to antigenic stimulation. Tissues from chicks given GH-depressing and non-GH-depressing vaccines were also collected and scored for histological changes in the head-associated lymphoid tissue (HALT) sites and the trachea. All 16 vaccines depressed the GH response to antigenic stimulation when given to 4-week-old chicks. Six of these vaccines (two Massachusetts, two Arkansas, and two Holland) also depressed the GH response when given to 2-week-old chicks, and one, an Arkansas vaccine, depressed the GH response when given to 1-day-old chicks. The main histological changes associated with the vaccines were increases in lymphocyte populations in the nasal mucosa, eyelid, and, for some, the lacrimal gland and the GH. In addition, lymphoid follicles were increased in the eyelid, to a lesser degree in the GH, and occasionally in the trachea. No relationship was found between histologic changes and vaccine-induced suppression of the GH response.

Animals↗
PubMed1995

Expression of cell cycle regulatory proteins in chronic lymphocytic leukemias. Comparison with non-Hodgkin's lymphomas and non-neoplastic lymphoid tissue.

The expression of certain cell cycle regulatory proteins: cdk1, cdk2, cdk4, cyclin A, cyclin B, cyclin E, Bcl2 and PCNA was examined in peripheral blood lymphocytes (PBL) from 25 cases of chronic lymphocytic leukemias (CLL) in order to analyze a possible cell cycle involvement of CLL lymphocytes. For comparison, we also studied the expression of these proteins in: 23 samples of non-Hodgkin's lymphoma (NHL) tissue of different histological types, 10 samples of non-neoplastic lymphoid tissue (NLT), non-stimulated PBL (NS-PBL) and PHA-stimulated PBL (PHA-PBL) from three healthy donors. Samples were lysed and proteins were resolved on polyacrylamide gel followed by Western blot. The expression of cdk4 and cyclin E, both known to act in early cell cycle stage, was approximately on the same level in all groups of lymphoid pathology examined. In particular, we found that that 19 out of 24 CLL cases were cyclin E positive and all but one were cdk4 positive, ie they expressed these markers over twice the level of non-stimulated healthy PBL. The cdk1 expression was above the level seen in NS-PBL in 14 (56%) cases, but the average expression was significantly lower than in the other tissues examined, including low-grade lymphomas. Cdk2 expression was comparable in CLL and in low malignancy grade NHL, but weaker than in other NHL and in NLT. Cyclins A and B, normally observed in advanced cell cycle phases, were not seen in any CLL case. The presence of cdk4 and cyclin E in the blood cells of the majority of CLL cases studied, as well as cdk1 and cdk2 in some cases, indicate that the CLL cells are not quiescent, but are blocked in an early stage of the G1 cell cycle phase, and/or that the expression of these proteins is pathologically deregulated.

Adult↗
PubMed1967

Lysosomes in lymphoid tissue. I. The measurement of hydrolytic activities in whole homogenates.

Methods have been developed for the quantitative assay of cytochrome oxidase, esterase, and 11 acid hydrolases in rat-spleen homogenates. These methods seem to be applicable also to other lymphoid tissues. Preliminary studies, extended to nine of the acid hydrolases, indicate that these enzymes occur in partly latent and sedimentable form and that they can be unmasked and rendered soluble by some of the treatments that liberate the enzymes from rat-liver lysosomes. The spleen particles appear to be very sensitive to mechanical injury, a property which necessitates special precautions in homogenizing the tissue. Agglutination of spleen particles takes place to a larger extent in 0.25 M sucrose than in 0.15 M KCl.

Animals↗
PubMed1997

The nasal-associated lymphoid tissue of adult mice acts as an entry site for the mouse mammary tumor retrovirus.

Mouse mammary tumor virus (MMTV) is a B type retrovirus transmitted to the suckling offspring through milk. MMTV crosses the intestinal barrier of neonates, initially infects the lymphoid cells of the Peyer's patches, and later spreads to all lymphoid organs and to the mammary gland. Adult mice can be infected systemically, but not by oral MMTV administration. In this study, we show that nasal administration of infected milk induces the infection of adult mice. Nasal MMTV infection shared the main features of systemic and neonatal intestinal MMTV infections: deletion of the superantigen (SAg)-reactive T cell subset from the peripheral T cell population, presence of viral DNA in lymphoid cells, and transmission of MMTV from mother to offspring. Viral DNA was restricted to the lungs and nasal-associated lymphoid tissue (NALT) 6 d after nasal infection. Furthermore, SAg-induced T cell proliferation was only detected in NALT. These results demonstrate that MMTV crosses the intact epithelium of the upper respiratory tract of adult mice and infects the lymphoid follicles associated with these structures.

Animals↗
PubMed1998

Changes in lymphoid tissue after treatment with a gonadotropin releasing hormone antagonist in the neonatal marmoset (Callithrix jacchus).

PROBLEM: The effect of neonatal treatment with a gonadotropin releasing hormone (GnRH) antagonist on the morphology and distribution of lymphocytes in lymphoid tissue of the infant marmoset was examined. METHOD OF STUDY: From a screened panel of antihuman antibodies for specific immune cells, antibodies for the CD20 and CD3 antigens showed excellent reactivity with marmoset tissue. Five sets of marmoset twins were treated with either the GnRH antagonist or a vehicle from birth, and were euthanized at 7 to 9 (3 sets) or 16 to 20 weeks (2 sets) of age. The spleen, thymus, and inguinal lymph nodes from each animal were processed for immunocytochemistry, and the number of cells expressing the CD20 and CD3 antigens were quantified. RESULTS: Control twins exhibited high plasma levels of testosterone, characteristic of the neonatal period, whereas testosterone concentrations were reduced (P = 0.001) to detection limits in the GnRH antagonist-treated twins. Microscopic evaluation suggested that treatment reduced the volume and cellularity of the thymic cortex, resulting in a decrease in the cortical-to-medullary ratio. Treatment reduced (P = 0.046) the number of thymocytes expressing the B-cell antigen (CD20) and marginally lowered (P = 0.067) the number expressing the T-cell antigen (CD3) in the thymic medulla. In the spleens of treated animals, periarterial lymphatic sheaths were less prominent on microscopic examination, and there were marginally fewer (P = 0.064) CD3+ cells. Numbers of CD20+ lymphocytes in the peripheral white pulp of the spleen and in the germinal centers of the lymph nodes, or CD3+ cells in the paracortex and germinal centers of the lymph nodes, were not altered by treatment. CONCLUSION: Neonatal treatment with a GnRH antagonist may alter maturational processes for B and T cells in the thymus and spleen of the marmoset and may deprive the immune system of its normal sensitivity to GnRH at a potentially critical time in development.

Animals↗