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Biomedical subjects

M G Lewis

Publications and source records attributed to M G Lewis.

At least 91 records · Page 5Linked to original sources
PubMed1979

Ia antigens on indeterminate cells of the epidermis: immunoelectronmicroscopic studies of surface antigens.

An antiserum against human B-lymphoblastoid cell membrane alloantigens (Ia-like antigens) was used to study the presence of such antigens on dendritic cells in human epidermis. Only Langerhans cells and the majority (85%) of so-called indeterminate cells were positively stained, as shown by immuno-electron microscopy. Fifteen percent of the indeterminate cells were negative and were considered to be immature melanocytes. A relationship exists between the indeterminate cell and the Langerhans cell. A proposal is made concerning emigration of Langerhans cells in response to haptenic stimulation, and the immigration of indeterminate cells to restore the status quo.

Antigens, Surface↗
PubMed1979

Immune derangement in patients with malignant melanoma.

The interaction between immune system and growing tumor can be expressed differently at different stages of the disease. This presentation covers three facets of these reactions in melanoma patients. A. The Primary Tumor. Time-lapse cinematography, with an analysis of lymphocyte movement demonstrated positive and negative chemotaxis against tumor tissues which correlated with their histological presence or absence within the primary tumor. B. The Regional Lymph Nodes. Histological examination of regional lymph nodes showed an increase in germinal center activity and B cell number, with a decrease in sinus histiocytosis and monocyte count as the tumor progressively invaded the node. This correlated with the elution studies, wherein the antimembrane antibody decreased and the anti-cytoplasmic antibody increased during the same period of progression. C. Humoral Immunity and Metastasis. Clinical metastasis heralded the decrease of anti-membrane antibodies with a rise in anti-immunoglobulins, especially anti-idiotypic antibodies and immune complexes containing tumor-directed antibody and either antigen or anti-immunoglobulin. This triad of anti-immunoglobulin, immune complexes and anergy as seen in other diseases with persistent antigenic stimulation, results in abnormal regulation and derangement.

Antibodies, Neoplasm↗
PubMed1979

Target role of Langerhans cells in mycosis fungoides: transmission and immuno-electron microscopic studies.

Langerhans cells of the epidermis are "special" macrophages, as indicated by their expression of Fc and C3 receptors and Ia antigen. Functionally, they can replace macrophages in presentation of antigens to T cells and in the MLR. Ultrastructural and immunologic studies were carried out on epidermal samples of mycosis fungoides. As in contact allergy, apposition of lymphocytes to Langerhans cells was noted. Destruction of Langerhans cells appeared to act as the focus for the development of Pautrier microabscesses. This destruction was accompanied by ingress of histocytic cells, probably related to the stem cell population for Langerhans cells. The target cell role of Langerhans cells appears to be similar in contact allergy and mycosis fungoides.

Antigens↗
PubMed1979

Malignant melanoma with renal dense deposits containing tumor antigens.

A patient with disseminated malignant melanoma developed mild renal failure with proteinuria four months following the diagnosis of his neoplasm. Renal biopsy showed a membranoproliferative glomerulonephritis. Electron microscopy revealed intramembranous dense deposits in the glomeruli as well as in tubular basement membranes and Bowman's capsule. Immunofluorescence microscopy demonstrated granular staining for C3 in these same locations and granular deposits of immunoglobulins in the glomerular capillary loops. Light and electron microscopy of the autopsy kidney obtained 5 months later revealed progression of the number, size and density of the deposits. Eluates from both autopsy and biopsy kidney contained melanoma antigen and anti-melanoma antibodies. This case illustrates the association between the dense deposits and neoplasia with the dense deposits representing immune complexes with the tumor as antigen.

Antigen-Antibody Complex↗
PubMed1979

Rhodopsin determinations in C57BL/6J-pallid strain mice.

The influence of light environment on rhodopsin concentration per eye was determined in littermate pigmented and nonpigmented C57BL/6J-pallid gene mice reared under cyclic light or continuous dark environments. Attempts to exacerbate a congenital manganese deficiency in pallid strain mice included dietary deprivation and supplementation with manganese and exposure to intense light followed by the determination of rhodopsin recovery rates in darkness. Homozygous pallid mice (pa/pa) reared in cyclic light had rhodopsin levels which were significantly lower than heterozygous (+/pa) or homozygous (+/+) black control mice. Dark-rearing resulted in a significant increase in rhodopsin per eye in pallid strain mice and equivalent levels in adult mice, but young pallid strain mice did not achieve the same rhodopsin concentration as young +/+ mice. Although dietary manganese deprivation or supplementation did not significantly alter rhodopsin levels among pallid mice, the deficient diet resulted in lower rhodopsin per eye in the young +/+ control animals. The recovery of rhodopsin in darkness following intense light exposure was equal and complete within 24 hr for most genotypes. However, recovery by pallid mice after 24 hr was significantly lower than by pigmented or albino genotypes.

Animals↗
PubMed1978

Immunologic changes in regional lymph nodes of melanoma patients.

In tumor-draining lymph nodes, humoral immunity is diverted from individually specific, cytotoxic anti-membrane AB to less specific anti-cytoplasmic AB with progression of the disease. Auto-anti-anti-bodies and suppressor cells seem to be involved in the failure of control of metastasis.

Antibodies, Neoplasm↗
PubMed1978

Immune reactions in patients with bladder and prostatic cancer.

Although there are many reports of cellular immune reactions in bladder and prostatic carcinoma patients, few have demonstrated the presence of humoral reactivity. The use of microtechniques, especially the enzyme-linked immunosorbent assay (ELISA), has made sequential studies possible on patients with early or small tumours. Using this assay, the presence of serum antibodies has been demonstrated in both bladder and prostate patients, the specificities of these reactions being checked against a battery of different tumours and normal tissues. In many of the patients, with low or transient antibody levels, the presence of circulating immune complexes was shown by the Raji cell assay and analysed by double counter-current immunoelectrophoresis (DCIE). The content of these complexes appeared to be either antibody and tumour antigen or antibody and antiimmunoglobulin. In a small series of cryosurgically treated prostatic carcinoma patients, the course of these antibodies was monitored over several weeks, and the fluctuations in antibody levels were related to the presence of these different types of complexes.

Antibodies, Neoplasm↗
PubMed1978

[Possibilities of immunotherapy in malignant melanoma].

The immune response of malignant melanoma bases on evident humoral and cellular defence mechanisms of the host against his tumor. Of special interest is a defective immune response, developing in the course of the disease. Hence, any immunotherapy aims at an immunostimulation and immunoregulation. Local and systemic nonspecific immunotherapy try to raise an immune response against the tumor by stimulating unspecifically the whole immune system. On the contrary, specific immunotherapy tries to stimulate directly the defence mechanisms against the tumor by transfusion of antisera (passive immunotherapy) and sensitized cells (adoptive immunotherapy) and by immunizing the patient with tumor tissue (active immunotherapy). One of the best ways in therapy of melanoma seems to be the combination of immunotherapy with chemotherapy, as yet employed in BCG and DTIC treatment.

Antigen-Antibody Reactions↗
PubMed1978

Specificity of tumor-associated antibodies in sera of patients with uveal melanoma.

We have identified antibodies against cytoplasmic components of allogeneic uveal melanoma cells in the sera of 16 of 31 patients with proven intraocular melanoma. Similar antibodies were found in 27% of controls and in 24% of patients with uveal nevi. The antibodies in these 3 groups of subjects were absorbed by components of uveal and cutaneous melanoma cells but not by those of normal choroidal melanocytes, normal uvea and retinal pigment epithelium, dermal nevus, pigmented skin or fetal cells. We found that specificity of the antibodies was also demonstrated by absence of reactivity with normal choroidal melanocytes, loss of reactivity after immune blocking, and absence of reactivity of melanoma antigen with conjugated antihuman immunoglobulin alone. Attempted absorption of the conjugated antihuman immunoglobulin by components of uveal melanoma cells did not alter the reactivity of the conjugated antihuman immunoglobulin.

Antibodies↗
PubMed1977

[The influence of humoral immune mechanisms on metastasizing tumors in humans (author's transl)].

Long-continued stimulation of the immune system by chronic infections or tumors leads to dysfunction of the immunoregulation. Different types of antibody, anti-antibody and immunocomplex point to the fact that it is not a matter of the weakening of the patient's immune defense but that these antibodies are important regulating mechanisms for the immune system. While antibodies directed against a tumor have a useful function for the patient with dissemination of metastasizing tumors, the anti-antibodies and antigenotypic antibodies represent a counterregulation which, in the advanced stage of the disease, eliminates the initial control.

Antibodies, Anti-Idiotypic↗
PubMed1977

[Replication of immune RNA by human lymphoblastoid cells].

Animal immune RNA used for the induction of the human lymphoblastoid cell line LDV/7, induces the appearance of receptor sites on the surface of these cells and the synthesis of specific immunoglobulins which are liberated into the culture medium. Furthermore, RNA has been extracted from these cells, which possesses the same properties of specific cytotoxicity as the RNA used for induction. It is supposed that the immune RNA derepresses specific genes on the genome of the induced cells.

Cell Line↗
PubMed1977

Complications of cancer immunotherapy with levamisole.

In a group of 69 patients receiving levamisole the drug had to be discontinued in 15 (21-7%) because of intolerable but reversible side-effects including gastrointestinal upset, "flu-like" syndrome, central nervous system disturbances, and skin rash. Reversible agranulocytosis with life-threatening sepsis occurred in a patient receiving levamisole immunotherapy for colonic carcinoma. Neutrophils and platelets were both severely affected. Levamisole-dependent leucoagglutinins appeared with circulating immune complexes during the acute phase of the illness, suggesting an immune drug reaction.

Adult↗
PubMed1977

Immunological studies in patients with malignant melanoma of the uvea.

Antibodies directed against different components of ocular melanoma cells were identified by indirect immunofluorescence in the sera of 12 patients with histologically proven malignant melanoma of the uvea. Antibodies reacing with autologous surface membrane antigens were found only in the sera of the 5 patients with the smallest tumors. The sera from most of the patients with small, large, or extraocular tumor contained antibodies directed against autologous cytoplasmic components while about one-half of the tests for antibodies reacting with allogeneic cytoplasmic antigens were positive. The incidence of positive tests with cytoplasmic antigens, in 67 patients with clinically diagnosed benign uveal nevi and 56 other individuals not showing evidence of proliferative lesions of uveal melanocytes, was 25%.

Adult↗
PubMed1976

Fetal antigens on the surface of human lymphoid cells.

Human B-lymphoblastoid cells established in long-term culture from healthy adults carry surface components that are normally found in human fetal tissues at about 10 wk of age. These antigens are strongly expressed on neoplastic B lymphocytes but not on thymocytes or a cultured T-cell line. They are carried by a small subpopulation of normal adult peripheral blood lymphocytes as well.

Antigens↗