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Biomedical subjects

B Morris

Publications and source records attributed to B Morris.

At least 145 records · Page 8Linked to original sources
PubMed1972

Ultrastructural analysis of antibody synthesis in cells from lymph and lymph nodes.

A variety of cells containing antibody were found in lymph from sheep responding to secondary challenges with horseradish peroxidase. Antibody was present in blast cells in lymph within the perinuclear space, the endoplasmic reticulum, the Golgi apparatus and on polyribosomes. Some lymphocytes in lymph also contained antibody but in these cells it was located principally in the perinuclear space. No cells were found containing antibody distributed throughout their cytoplasm nor were any lymphocytes found with a Golgi apparatus positive for antibody. After the immune response in the lymph had died away, a population of cells containing antibody was still present in the regional lymph node. These were all plasma cells in which the antibody was present for the most part in a highly organized endoplasmic reticulum. Cells of this type were never found in the lymph. The cells containing the smallest amounts of antibody had a few discrete focal points in the perinuclear space and a few positive groups of ribosomes in their cytoplasm. The endoplasmic reticulum in some cells was filled completely with antibody, while in others positive segments were found adjacent to negative ones. The antibody in the cytoplasmic endoplasmic reticulum was in continuity with the antibody in the perinuclear space. The Golgi apparatus contained antibody in only a small proportion of the cells but when it was positive it was strongly so, suggesting that antibody was concentrated in this organelle. In some cells a positive reaction to horseradish peroxidase antibody appeared in the nucleus over the nucleoli. The significance of this finding is not known.

Animals↗
PubMed1971

The lymphatics of the kidney and the formation of renal lymph.

1. The anatomy of the renal lymphatics and the flow and composition of renal lymph have been investigated in sheep. Lymphatic capillaries were demonstrated in the cortex and cortico-medullary areas of the sheep's kidney but not within the medulla. The lymph formed in the sheep's kidney drains from the hilum through several small lymphatics; there is no lymphatic drainage from the renal capsule.2. Lymph flow from the sheep's kidney varied from 0.5 to 3.0 ml./hr. The concentrations of electrolytes and urea in renal lymph were found to be similar to lymph from other regions of the body, but the concentration of endogenous creatinine was lower. The average concentration of protein in renal lymph was 43% of the plasma levels; there was a significantly higher proportion of albumin in renal lymph than in plasma. When labelled albumin was injected intravenously, the specific activities of the plasma and renal lymph albumin equilibrated in about 2 hr.3. When [(14)C]inulin, [(125)I]hippuran or [(14)C]creatinine were infused intravenously radioactivity appeared rapidly in the renal lymph. When steady-state levels were reached in the circulating plasma, the renal lymph/jugular vein plasma ratios for [(14)C]inulin and [(14)C]creatinine were 0.82 while for [(125)I]hippuran the ratio was 0.34. It was considered that the concentration of these substances in renal lymph was similar to the concentration in renal vein plasma.4. The concentration of renin enzyme was on the average about 8 times higher in renal lymph than in jugular vein or renal vein plasma or in lymph from the hind limbs.5. Renal lymph appeared to be formed principally, if not entirely, in the renal cortex and appeared to be a modified filtrate derived from post-glomerular blood capillaries. If any contribution to renal lymph does come from the medulla, it must be small in relation to the volume of lymph formed in the cortex.

Albumins↗
PubMed1970

The role of the lymphatic system in the rejection of homografts: a study of lymph from renal transplants.

The rejection of renal homografts has been studied in sheep by transplanting kidneys into the neck and preserving the renal lymphatic drainage intact. Chronic fistulae were established in the transplanted renal lymphatics and lymph collected throughout the life of the graft. The changes that occurred in homografts during the process of rejection were reflected in changes in the lymph. Large numbers of basophilic, blast, lymphoid cells appeared in the lymph, and lymph production in the grafted kidney increased 20-50 fold. Over a period of about 10 days, up to 60 g wet weight of lymphoid cells and up to 10 liters of lymph were collected from the graft. Within 24 hr of grafting, the host cells present in the renal lymph had become sensitized to the graft and transformed into blast cells when cultivated in Millipore chambers in vitro. When the cells leaving the graft during the first 18-48 hr were injected into distant nonstimulated lymph nodes of the host sheep, they evoked significant cellular and antibody responses in the nodes. Within the graft, the main pathological changes were found in the vascular endothelium and many of the peritubular capillaries become plugged with emboli comprised of blast cells. There was extensive infiltration of the renal parenchyma with lymphoid cells and evidence of their transformation and proliferation within the renal blood capillaries. When all the lymph and cells leaving the homograft were diverted from the body, there was a greatly decreased reaction in the regional prescapular lymph node, and no reaction in lymph nodes distant from the graft. In these circumstances, the survival of the graft was not prolonged, and it was rejected without involvement of the lymph nodes of the host. Humoral antibody was produced in the lymph node regional to the homograft within 48-60 hr of grafting. Antibody was not detected in the blood or in the renal lymph until near to the time the graft was rejected. It was thought that this was due to the binding of antibody by the kidney graft tissue. We conclude that all the events which lead to the recognition and rejection of renal homografts can occur centrally within the graft itself.

Animals↗
PubMed1967

The ultrastructure and function of the cells in lymph following antigenic stimulation.

When a lymph node receives an antigenic stimulus the cell population in the efferent lymph changes and large basophilic cells appear. During a secondary immune response cells of this type may account for over 50% of the cells present in lymph. When examined by electron microscopy, many of these cells were found to be primitive undifferentiated blast cells with many free ribosomes in their cytoplasm and only an occasional piece of endoplasmic reticulum. Their nuclear chromatin was sparse and the nuclei contained several nucleoli. Many other cells which were judged to be more differentiated had large numbers of ribosomes arranged in clusters which took the form of rosettes or spirals. These cells also had more ergastoplasm but this occurred usually in the form of short pieces of disorganized endoplasmic reticulum. No cells with the ultrastructure of classical plasma cells were found in efferent lymph although these cells were abundant in the stimulated lymph nodes. It was shown that when the lymph which contained these cells was collected quantitatively no systemic immunity developed even though a vigorous immune response took place in the lymph node with the formation of many plasma cells. Failure of the systemic immune response to develop could not be explained merely in terms of the loss of antibody. It was concluded that these basophilic cells rather than antigen are responsible for propagating the immune response throughout the body and that they depend on an intact lymphatic pathway for their immediate transport. This view was supported by experiments which showed that these cells are capable of initiating immune responses in other lymph nodes of the same animal and of transferring active immunity between chimeric twins. The most likely explanation of these results is that the basophilic lymphoid cells carry out their messenger function by developing into plasma cells at sites remote from the site at which antigen is localized. However this has yet to be proven and the possibility remains that these mobile, highly motile, RNA-rich cells may express their messenger function by transferring information to other effector cells.

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