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Biomedical subjects

R Hong

Publications and source records attributed to R Hong.

At least 181 records · Page 10Linked to original sources
PubMed1976

Synthesis of secretory component by human colon cancer cells.

Colon carcinoma, established in long-term tissue culture, has been shown to synthesize secretory component (SC). These molecules can be demonstrated both on the cell surface and in the cytoplasm by immunofluorescence. Regeneration of SC was demonstrable after trypsinization of the cells. In culture, two lines of carcinoma epithelium were shown to incorporate (14C) leucine into newly synthesized SC. These cell lines should provide useful preparations for studying the details of immunoglobulin-SC interactions.

Cell Line↗
PubMed1976

Morula forms of E rosettes: distribution, specific inhibition, and enhancement.

Rosetts-forming cells (RFC) with more than 10 sheep red blood cells (SRBC's) per cell defined as morula-forming cells (MFC) were studied in human lymphoid organs and in the peripheral blood (PBL). MFC are most common in the thymus (more than 50%) and the frequency is much less in peripheral lymphoid tissues and in the blood (29.8% in those less than 5 years old; 14.9% in adults). There is very slight decrease in total RFC in PBL over age 5, but the changes in MFC are quite striking. Treatment with antihuman thymus antiserum (ATS) and with anti-human lymphoblastic antiserum (ATL) resulted in significant inhibition of total rosette and morula rosette formation. No inhibition was seen using normal brain antiserum, anti-IgM antiserum, or anti-L chain antiserum. In two patients with chronic lymphocytic leukemia and in some cases of thymic deficiency the ratio of MFC to total RFC was unusually high. After culture with phytohemagglutinin (PHA) and conversion to blast forms or after surface peturbation by papain or freeze-thaw treatment, MFC numbers were increased.

Humans↗
PubMed1976

Peptide-binding macromolecules in the blood of seriously ill or mentally retarded patients.

This report describes macromolecules that bind (des-aspartic acid1)-angiotensin II, the des aspartic acid1 derivative of angiotensin I, and several biologically active and inactive analogues of these polypeptides. The macromolecules were found in the plasma of approximately 2 per cent of ambulatory adults and hospitalized children and 32 per cent of the patients at two institutions for the mentally retarded. The binding properties of these macromolecules were studied by incubating with peptides labeled with 125iodine, and separating bound from free labeled peptide using small gel filtration columns. The peptide-binding macromolecules from several patients were compared. They showed very similar specificity for a group of arginyl peptides of the des-aspartyl1-angiotensin sequence. The plasma binders differed from one another in their optimum pH and their mobility in electrophoretic fields. Those with more acid pH optima displayed more rapid electrophoretic mobility. The binders fell into two classes based on apparent molecular weight, approximately 140,000 and 250,000. Those with the higher apparent molecular weight contained a large proportion of binder that could be precipitated with antiserum to human IgA. Kinetic measurements showed that the plasma binders were somewhat heterogeneous with respect to affinity for (des-asp1)-angiotensin, with apparent association constants ranging from 10(7) to 10(8) M-1. Binding activity was labile to heat, and to treatment with pepsin or trypsin. It was inhibited by calcium, protamine, streptomycin, and some other cationic compounds. The plasma peptide binder differed in specificity and molecular weight from soluble angiotensin-binding molecules extracted from tissues, and from properties expected of a receptor for angiotensin. These macromolecules may be useful reagents for measuring (des-asp1)-angiotensins. Their presence in plasma samples may interfere with angiotensin assays in some circumstances.

Angiotensin II↗
PubMed1975

Treatment of severe combined immunodeficiency with bone-marrow from an unrelated, mixed-leucocyte-culture-non-reactive donor.

A 7-month-old boy with severe combined immunodeficiency had no relative who was a suitable bone-marrow donor as determined by mixed-leucocyte-culture (M.L.C.) testing. In the general population an M.L.C.-nonreactive, unrelated donor was found among individuals who were identical with our patient at the Four locus. Following a bone-marrow transplant this child showed signs of rapid immunological reconstitution and only a mild graft-versus-host reaction. Unfortunately, the child died 31 days post-transplantation of cytomegalovirus infection. The findings support the hypothesis that matching for lymphocyte-defined antigens among unrelated individuals will permit successful immunological reconstitution.

Bone Marrow Cells↗
PubMed1975

Antihistamine blockade of the ovarian hyperstimulation syndrome. II. Possible role of antigen-antibody complexes in the pathogenesis of the syndrome.

Antihistamine can prevent the ovarian hyperstimulation syndrome in the rabbit. The mechanism underlying this experimental observation has not been elucidated. Our experiments were directed at the question of whether antigen-antibody complexes are a factor in the development of the ovarian hyperstimulation syndrome. The results do not support the theory that antigen-antibody complexes play a role in the pathogenesis of this syndrome.

Animals↗
PubMed1975

Thymus transplants: a look to the future.

In a review of thymus transplants performed in a variety of immunodeficiency syndromes, results in the DiGeorge syndrome seen uniformly successful. Rapid restoration of lymphocyte responsibility in vitro and achievement of normal peripheral blood lymphocyte counts are characteristic. In nearly all other types of isolated thymic deficiency or combined immunodeficiency there has been only transient or meager restitution and more often than not complete failure. A few exceptions were noted in a combined immunodeficiency state and in two cases of isolated T-cell deficiency. The use of transfer factor may have played an important adjunctive role. Future attempts must depend upon more precise characterization of the defects, utilizing attempts to define subpopulations of T and B cells; consideration of HL-A restrictions; methods of implantation and use of adjunctive measures (eg thymosin) or other cell populations (such as liver or spleen).

Adolescent↗
PubMed1975

Selective IgA deficiency---some perspectives.

The clinical spectrum of IgA deficiency varies from good health to respiratory, gastrointestinal, autoimmune and malignant disorders. Evaluation of B lymphocytes with surface IgA receptors in this disease reveals cap formation, decreased to normal density of IgA receptors, and IgA secretion following pokeweed stimulation. Further study of antigen-induced B-lymphocyte phenomena is needed. The presence of decreased numbers of T-cell markers in some individuals with IgA deficiency suggests a T-"helper" cell defect.

Antibody Formation↗
PubMed1975

Deficiency of secretory Ig-A and intestinal malabsorption.

A patient under treatment with hemodialysis suffered increasing clinical and laboratory evidence of intestinal malabsorption. Jejunal aspirates revealed heavy bacterial and mycotic flora within the proximal jejunum. Secretory Ig-A and secretory component were present only in trace amounts. The deficiency of the generally ubiquitous secretory component is particularaly striking. Oral administration of 20-30 ml. colostrum daily reversed not only the clinical evidence but also laboratory findings of intestinal malabsorption.

Colostrum↗
PubMed1974

Small intestinal disease in T cell deficiency.

Biopsies of the proximal small bowel were obtained in four children with impairment of cell-mediated immunity, chronic diarrhia, and malabsorption; one child had an isolated T cell defect and three had significant B and T cell defects. All of them had malabsorption and, in addition to alterations of the small bowel epithelium, large vacuolated macrophages were seen in the lamina propria in all biopsies. Electron microscopy demonstrated lipid and patches of small pleomorphic inclusions within the macrophages. Since large vacuolated macrophages have also been described in Whipple's disease and chronic granulomatous disease, we suggest the possibility of a common thread of defective host defense and gastrointestinal malfunction in these three conditions.

B-Lymphocytes↗