PubMed Health⌕ Search

Biomedical subjects

I Olah

Publications and source records attributed to I Olah.

At least 37 records · Page 2Linked to original sources
PubMed1986

Effect of carrageenan on the histology of the bursa of fabricius and the humoral immune response to Salmonella O antigen.

Bursal secretory cells have been studied with light and electron microscope after prolonged carrageenan treatment. Intravenous injected carrageenan decreased the number of secretory cells as early as 4 days after the first carrageenan administration. Degranulation of the secretory cells may have made it difficult to identify these cells. The discharge of granules from the secretory cells was indicated by the appearance of a large amount of extracellular substance on the cell surface. The carrageenan may have accelerated the IgM-IgG switch after immunization with Salmonella O antigen. The rapid IgM-IgG switch was preceded by degranulations of the secretory cells. Therefore, the secretory products of the cells might have contributed to the switch. The number of secretory cells in the carrageenan-treated birds increased by the secondary immunization. Many of these secretory cells were immature and located close to the corticomedullary border. The young cells revealed a large blastlike nucleus and bulky cytoplasm with granules surrounding the cytocentrum and Golgi zone.

Animals↗
PubMed1985

Effect of surgical bursectomy on the ellipsoid, ellipsoid-associated cells, and periellipsoid region of the chicken's spleen.

Surgical bursectomy resulted in cellular depletion of the periellipsoid white pulp, confirming its bursa dependency. Also, in bursectomized birds, the ellipsoid could not be identified, although a small number of abnormal ellipsoid-associated cells (EAC) were observed in the periellipsoid region. The most characteristic finding was the degeneration of the EAC. Degeneration of EAC indicated that the intact bursa was mandatory for normal differentiation of cells of the periellipsoid white pulp into EAC. The promoting effect of the bursa might take place by a bursal hormone. The histological impairment of the EAC was followed by reduced carbon binding and migrating capabilities. Bursectomy resulted in a shift in bacterial phagocytosis in that many cells of the periellipsoid phagocytosed Salmonella. The reduced heterophil infiltration of the ellipsoid in bursectomized birds might be explained by the impaired granular content of the EAC. The impaired migration capability of the EAC might contribute to the low number of germinal centers in bursectomized birds.

Animals↗
PubMed1985

Lymphocyte migration through the lymphatic sinuses of the chicken's lymph node.

We have described the lymphocyte migration through the sinus wall of the lymph node. The sinuses showing lymphocyte migration are located in a given area of the node that might be comparable with the T-dependent deep cortex of the mammalian lymph nodes. The lymphocyte migration takes place through the cytoplasm of the endothelial cell presumably by formation of the transendothelial channels, which are produced by vesicles of the endothelial cell. The intensive vesiculation preceding the formation of transendothelial channels might indicate the direction of the migration. The absence of vesicles in the endothelial cell and the dilated intercellular space between the lymphocyte and endothelial cell suggest that the lymphocyte in the sinus wall may be "resting". The presence of the multivesicular body in the pseudopod or in the vicinity of the pseudopod of the lymphocyte may contribute to the migration.

Animals↗
PubMed1984

Lymphopineal tissue in the chicken.

We have studied the chicken's pineal gland by light and electron microscopy at 3 and 4 weeks of age. The results indicated that lymphocytes, plasma cells, secretory cells, basophil and eosinophil granulocytes enter the parenchyma and a new histologically defined tissue is formed which we call lymphopineal tissue. Inside the pineal parenchyma, the number of thymidine labeled cells is almost three times higher than in the interstitium suggesting that the pineal's products might be blastogenic for the cells and/or exert an influence on post-thymic T-cell differentiation.

Animals↗
PubMed1983

Ascites formation in the chicken.

We have observed the rapid development (4 to 7 hr after injection) of an ascitic condition in the hepatoperitoneal sac after the i.v. injection of large amounts of carbon. The amount of ascitic fluid varied from .5 to 12 ml/chicken. The protein content of the fluid was identical with that of the sera, but the specific IgM immunoglobulin was lower in the ascitic fluid than in the sera. The cellularity of the ascitic fluid was poor. Mononuclear cells containing lipid and phagosomes and aggregated thrombocytes were the predominant cells. A mechanism regulating water balance between the liver and cecal pouch was suggested by the ascitic fluid data.

Animals↗
PubMed1981

Effect of levamisole on the phytohemagglutinin induced basophil hypersensitivity reaction in the chicken wattle.

The potentiating effect of levamisole (L) on the phytohemagglutinin (PHA) induced hypersensitivity skin reaction in the chicken's wattle was studied. The L increased the number of heterophils and basophils 10 and 6 times, respectively. The number of mononuclear phagocytic cells in the PHA skin reaction was unaltered. These results contrast slightly with those of mammals.

Animals↗
PubMed1980

Lectin-induced giant cell formation in the chicken wattle.

The fusion of mononuclear cells has been observed in inflammatory reactions and in cell culture experiments. This report describes the in vivo fusion of macrophages and their cytological structures. Thick (1 micrometer) and thin sections of wattle were prepared 6, 12, 24, 48, and 96 hr after a single subcutaneous-wattle injection of phytohemagglutinin (PHA-P; .1 ml; 100 microgram) in saline. The injection of PHA-P induced withn 6 hr a blood borne mononuclear cell infiltration of the chicken's wattle. Giant cells (3 to 8 mononuclear cells) were found by 24 hr, reached a maximum number by 48 hr and declined perceptibly by 96 hr. After 48 hr the mononuclear cells possessed a well-developed Golgi apparatus, ergastroplasmic cisternae, and large amounts of glycogen-like granules which diminished by 96 hr. The influence of lectin on the glycogen content of macrophages is similar to published observatins on small lymphocytes and suggests a similar carbohydrate metabolism between these two cell types.

Animals↗
PubMed1979

Structure of the germinal centers in the chicken caecal tonsil: light and electron microscopic and autoradiographic studies.

The light and electron microscopic structure of the germinal center of chicken caecal tonsils were studied. Two kinds of germinal centers were revealed; the first was located deep in the lymphatic tissue close to the muscle layer of the caeca. These germinal centers frequently have an incomplete capsule, and are not, therefore, separated from the diffuse lymphatic tissue. The second kind of germinal center was located closer to the epithelium and had a complete capsule separating it from the diffuse lymphatic tissue. Both germinal centers possessed an outer dark cortical zone which contained smaller lymphoblasts (of less than 10 micron in diameter) and a central medullary area which contained larger lymphoblasts (up to 16 micron). Autoradiographic studies revealed that the small lymphoblasts of the outer cortical zone are concerned with cell generation and that the large lymphoblasts of the medullary area may have derived from the small lymphocytes. Within the medullary area of the germinal center are cells which are embedded in an intercellular substance of high density. We propose that the intercellular substance may be a product of this cell. For discussion purposes we have called this cell a secretory cell. The secretory cell may originate from a small lymphocyte-like cell.

Aging↗
PubMed1979

The chicken's femoral-lymph nodules: T and B cells and the immune response.

Femoral lymph nodules (FLN), which are barely perceptible in normal birds, after a footpad injection of sheep red blood cells (SRBC) may either significantly enlarge (responder) or remain reduced in size (nonresponder). There were approximately 38% T cells and 53% B cells in the FLN of responder chickens. Significantly more plaque-forming cells (PFC) developed in the FLN than in the spleen after a footpad injection of SRBC. Total antibody, mercaptoethanol- (ME) resistant, and ME-sensitive fractions were significantly higher in birds given i.v. than in those given footpad injections. There were no differences in PFC and agglutinin titers between FLN-responders and nonresponders. The number of PFC in FLN exceeded the number of splenic PFC previously reported. The high PFC response of the FLN may reflect the large percentage of B cells in this lymphomyeloid tissue or the presence of antigen-experienced B cells in the FLN. Although FLN may influence a systemic immune response its major role appears to be restricted to a local response.

Animals↗
PubMed1978

A scanning electron microscope study of the caecal tonsil: the identification of a bacterial attachment to the villi of the caecal tonsil and the possible presence of lymphatics in the caecal tonsil.

A scanning electron microscope (SEM) was used to compare the proximal region (PR) and distal region (DR) of the caecum. The caecal tonsil (CT) occupied the initial 4-10 mm of the PR. Villi were present in the PR and absent from the DR. Segmented structures were attached to the surface of PR. Transmission electron microscopy (TEM) revealed these structures to be bacteria. No difference in surface morphology could be discerned between the CT and the remainder of the PR. Lymphatic vessels were observed in the CT by employing TEM.

Animals↗
PubMed1978

The number and size of the follicular epithelium (FE) and follicles in the bursa of Fabricius.

In a four-week-old chicken .1 ml carbon solution was deposited on the vent. The carbon was sucked into the lumen of the bursa and absorbed by the follicular epithelium which appeared as black dots on the surface of the folds. The number of black dots on the surface of a fold represents the number of follicles per fold. The average number of follicles per fold was 820. Since the number of folds per bursa ranges between 10--15, we were able to calculate 8000--12000 follicles per bursa. The volumetric mathematical analysis of the follicles and folds confirmed our calculated number of follicles. On a stereomicrograph from a randomly selected area of a fold surface, a trapezoid was outlined and measured. The surface analysis of the black dots within a trapezoid area revealed that about 10% of the bursal surface was covered by follicular epithelium which is immunologically oriented.

Animals↗
PubMedDate not supplied

Anti-S-100 antibody recognizes ellipsoid-associated cells and other dendritic cells in the chicken spleen.

The chicken spleen was studied immunohistochemically with anti-S-100 protein polyclonal antibody. S-100-positive cells accumulated around the penicilliform capillaries during the first 3 weeks of life. After 2 weeks posthatch the S-100-positive cells appeared in the red pulp, periarterial lymphatic sheath, and subsequently in the germinal center. Their ontogenetic development and intrasplenic distribution strongly suggested that the S-100-positive cells were identical with ellipsoid-associated cells. The S-100-negative cells of the periellipsoidal white pulp gradually transformed to S-100-positive, functionally active cells on the surface of the ellipsoid. The immunohistological findings support the hypothesis that the interdigitating dendritic cells and follicular dendritic cells were not of monocytic origin but belong to a splenic resident, endocytic cell line located on the surface of the ellipsoid.

Animals↗