Jeike Biewenga

The role of nasopharyngeal lymphoid tissue

Nasal-associated lymphoid tissue (NALT), which comprises paired lymphoid organs in the nasopharynx of rodents, is the principal mucosal lymphoid tissue of the respiratory tract. As described in this review, NALT bears certain similarities to the Peyers patches of the intestine but the two differ remarkably in morphology, lymphoid migration patterns and the binding properties of their high endothelial venules (HEV).

Macrophage depletion in the rat after intraperitoneal administration of liposome-encapsulated clodronate: Depletion kinetics and accelerated repopulation of peritoneal and omental macrophages by administration of freund's adjuvant

The purpose of this study was to develop a method for the depletion of macrophages from the peritoneal cavity and the omentum of the rat. Rats received two intraperitoneal injections (at days 0 and 3) with liposome-encapsulated clodronate (dichloromethylene bisphosphonate: Cl2MBP-liposomes). This treatment resulted in complete elimination of mature tissue macrophages (ED2-positive macrophages) from the peritoneal cavity and the omentum within 2 days. The elimination included the strongly ED2-positive spindle-shaped cells of the omental membrane. Repopulation of the omental ED2-positive macrophages was not seen within the next 23 days. Whereas ED2-positive macrophages were completely depleted, few ED1-positive cells remained and repopulation of ED1-positive cells was faster. The treatment further depleted macrophages from the spleen, especially from the red pulp, parathymic lymph nodes and liver. Freunds incomplete adjuvant administered one day after the last injection of Cl2MBP-liposomes considerably accelerated repopulation in the omentum. The protocol described might be used to investigate the contribution of mature tissue macrophages to the induction of immune responses, drug metabolism and the elimination of intestinal tumours.

LDH-IgA immunoglobulin complexes in human serum.

Human sera containing complexes of lactatedehydrogenase (LDH) and immunoglobulin A (IgA) were studied. Such complexes could be demonstrated in a number of sera with abnormalities in electrophoretic pattern of the LDH isoenzymes. LDH-IgA complexes were observed in a number of sera in which the LDH-2 band was missing, in a serum with all LDH activity in the betta-gamma-globulin region, but also in some sera with only minor abnormalities in the LDH isoenzyme pattern. It is shown that the IgA bound to LDH is of the kappa light chain type. Auto-bodies were not detected in the sera. Therefore, the formation of the LDH-IgA complexes does not seem to be the result of an antigen-antibody reaction.

An immunohistochemical study on the postnatal development of rat nasal-associated lymphoid tissue (NALT)

SummaryThis study concerns the development of nasal-associated lymphoid tissue in the rat, using immuno- and enzyme-histochemical staining techniques on cryostat sections. Nasal-associated lymphoid tissue is present at birth as a small accumulation of mainly T lymphocytes and non-lymphoid cells; B cells are rare. Distinct areas of T and B cells appear at 10 days after birth; by that time high endothelial venules are also observed. Intra-epithelial lymphocytes are present, most of them being T-helper cells. ED1+ macrophages are seen throughout the tissue. The proportion of ED1+cells does not change during ontogeny. ED2+cells (tissue macrophages) are present predominantly at the border between the lymphoid tissue and the surrounding connective tissue, in all age-groups. ED3+mononuclear cells are scattered throughout the nasal-associated lymphoid tissue of young animals. Later on, the ED3+ cells migrate into the border-area between lymphoid and connective tissue. Ia+ non-lymphoid cells in the nasal lymphoid tissue increase in number during ontogeny. Only a few of them show acid phosphatase activity, indicating that the proportion of classical scavenger macrophages is low. Some of them may be antigen presenting (dendritic) cells. Ia+ dendritic cells also occur between the epithelial cells. Moreover, some epithelial cells express the Ia marker.

Lymphoid and non-lymphoid cells in nasal-associated lymphoid tissue (NALT) in the rat

SummaryLymphocyte and macrophage subpopulations and the stroma of mucosa-associated lymphoid tissue in the nasal cavity of the rat were examined by application of immunohistochemical and enzyme histochemical methods to cryostat sections. Nasal-associated lymphoid tissue was composed of a loose reticular network with lymphocytes and macrophages, covered by epithelium. The epithelium was infiltrated with B cells, T helper (W3/13-positive) and T suppressor/cytotoxic or large granular cells (OX8-positive), ED1-positive macrophages and Ia-positive cells. The B cell areas were populated by B cells, immunopositive for surface IgM or IgG. B cells with surface IgA or IgE were rare. Germinal centres were found infrequently. T helper cells were scattered throughout the B cell area. A few ED1-positive macrophages and ED5-positive follicular dendritic cells were observed. Strong Ia staining (mostly of B cells) was found in this area. The T cell areas contained T helper and T suppressor/cytotoxic cells in about equal amounts, and numerous ED1-positive macrophages. ED1 staining was also found in the subepithelial area. Numerous ED1-, ED2- and ED3-positive macrophages were found in the border between the lymphoid mass and the surrounding connective tissue. A few non-lymphoid cells showed weak acid phosphatase or non-specific esterase activity. The morphological observations suggest that nasal-associated lymphoid tissue plays an important role in the first contact with inhaled antigens.

Lactate dehydrogenase isoenzyme(s) linked to IgA immunoglobulin in a patient with a myocardial infarction

Abstract An anomaly of lactate dehydrogenase (LDH) in the serum of a patient with myocardial infarction is reported. Investigations showed that, next to a normal LDH1 fraction, two macromolecular fractions with lactate dehydrogenase activity were present. Routine immunoelectrophoretic technique followed by specific staining for lactate dehydrogenase activity showed that a linkage must be present between one (or more) isoenzyme(s) and immunoglobulin IgA.

The localization of macrophage subsets and dendritic cells in the gastrointestinal tract of the mouse with special reference to the presence of high endothelial venules. An immuno- and enzyme-histochemical study.

SummaryThis study concerns the distribution of macrophages and dendritic cells (DC) in the gastrointestinal tract of the mouse. Heterogeneity of macrophage population was found by using the MOMA-1, MOMA-2, ERTR-9, Mac-1 and F4/80 monoclonal antibodies. MOMA-1, ERTR-9, Mac-1 and F4/80+ cells were detected mostly at the villous cores in the lamina propria of the villi, whereas MOMA-2+ cells were primarily found around the crypts at the base of the villi. These MOMA-2+ cells revealed a granular appearance throughout the cytoplasm and displayed a strong acid phosphatase (AcPh) activity. Few MOMA-2+ cells were seen at the top of the villi in the epithelium. Although MOMA-1 and ERTR-9+ cells have similar morphology and the same distribution patterns in the lamina propria, they are likely different populations, because in Peyers patches (PP), MOMA-1+ cells were present, whereas ERTR-9+ cells could not be detected. Both populations displayed AcPh activity. Strongly stained Mac-1+ cells were abundantly seen in the lamina propria of the small intestine. F4/80+ cells were rare. NLDC-145+ cells with AcPh activity and weak Ia staining were also found. In the PP-associated villi and in the T-dependent area of PP, dendritic NLDC-145+ cells, which were strongly Ia positive, were detected. MIDC-8+ cells were found only in the T-dependent area. Few NLDC-145+ cells (dendritic cells) were found in the upper part of the oesophagus. These cells were also stained with the MIDC-8 antibody. The MECA-325 monoclonal antibody recognized high endothelial venules (HEV) in PP and blood vessels at the base of the villi of the jejunumileum and caecum. Unlike in PP, the endothelium of the venules in the villi was flat.

Lactate dehydrogenase (LDH)-IgG3 immunoglobulin complexes in human serum

Sera of fifteen patients containing complexes of LDH and IgG were analysed. The LDH-IgG complexes of fourteen of these patients were investigated for their subclass specificity. They appeared to consist of LDH and IgG3, except for one of the patients. The serum of the latter patient also contained complexes of LDH and IgG1. In this serum both types of the immunoglobulin light chains were involved in the formation of the complexes, whereas in the serum of the patients with LDH-IgG3 complexes alone, they only contained one of the two immunoglobulin light chain types; it mainly concerned kappa type. The results of the present study were compared to those of a previous study on LDH-IgA complexes, in which the IgA fraction always contained light chains of kappa type. The mean LDH activity and the heat stability of the LDH activity in the sera with LDH-IgA complexes appeared to be higher than in the sera with LDH-IgG3 complexes. In contrast to complexes of LDH and IgA which occurred in all age groups LDH-IgG3 complexes were mainly found in elderly persons. Although auto-antibodies to different tissue antigens were present in the majority of the sera containing LDH IgG3 complexes, antibodies to LDH could not be demonstrated. A relationship between the presence of the complexes in the serum and a particular disease could not be established.

Serum lactate dehydrogenase isoenzymes linked to immunoglobulin A

Abstract Electrophoretically abnormal serum LDH isoenzyme patterns due to the presence of LDH-IgA complexes are described. Evidence was obtained indicating that the complex formation is caused by the presence of an anomalous immunoglobulin A.

Evaluation of monoclonal antibodies with specificity for human IgA, IgA subclasses and allotypes and secretory component. Results of an IUIS/WHO collaborative study.

51 monoclonal antibodies (McAb) with putative specificity for human IgA, the IgA subclasses, Am allotypes or secretory component (SC) were evaluated for immunoreactivity and specificity by nine laboratories employing immunodiffusion, agglutination, immunohistological assays, immunoblotting and direct binding and competitive inhibition enzyme immunoassays. McAbs specific for IgA PAN (n = 24), IgA1 (n = 7), IgA2 (n = 3), IgA2m(2) (n = 2), non-IgA2m(2) (n = 4) and SC or secretory IgA (n = 5) were identified that were immunoreactive and specific in the assays employed. The McAbs identified as IgA- or SC-reactive were shown to be non-reactive to human IgG, IgM, IgD, IgE, kappa and lambda by direct binding and competitive inhibition immunoassays. Interestingly, no McAbs with restricted specificity for IgA2m(1) were identified. Some McAbs displayed higher affinity and/or better performance in one or several of the assay groups. The IgA- and SC-specific McAbs identified in this international collaborative study have potential as immunochemical reference reagents to identify and quantitate monomeric and polymeric IgA in human serum and secretions.