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Biomedical subjects

N F Mendes

Publications and source records attributed to N F Mendes.

At least 37 records · Page 2Linked to original sources
PubMed1983

Detection of human T-lymphocyte receptor for sheep erythrocytes in immunoregulatory alpha-globulin.

Immunoregulatory alpha-globulin (IRA) has been shown to suppress T cell-dependent immune responses including inhibition of E-rosette formation between human peripheral lymphocytes and sheep erythrocytes. The human lymphocyte receptors, responsible for the interaction with E, can be obtained in soluble form. Recent papers have indicated that these soluble E-receptors may play a regulatory role in the thymus-dependent immune response. In the present paper a possible relationship between IRA and soluble E-receptors was investigated. Absorption of IRA with sheep erythrocytes removed its inhibitory effect upon both E-rosette formation and lymphocyte response to phytohemagglutinin. In gel diffusion experiments a pattern of total identity was obtained between a component of IRA and soluble E receptors, revealed by an anti-E-receptor-specific antiserum (obtained by immunizing a sheep with autologous erythrocytes sensitized with human soluble E-receptors). These results indicate that IRA preparations contain soluble E-receptors. The possibility that E-receptors may be related, to some extent, to the inhibitory effects of IRA protein deserves further investigation.

Absorption↗
PubMed1983

Detection of the human T lymphocyte soluble receptor for sheep erythrocytes by double gel diffusion.

An anti-human T lymphocyte serum specific to the membrane receptor for sheep erythrocytes (E) was produced by immunizing sheep with the autologous E-soluble E receptor complex. The soluble E receptor (RS) was obtained by heating human lymphocytes at 45 degrees C for 1 h. The anti-RS serum reacted by double gel diffusion with preparations containing Rs such as the supernatant of heated peripheral lymphocytes (SHPL), the supernatant of heated spleen lymphocytes (SHSL) and concentrated normal human serum (NHSc), producing a single precipitation line with each preparation. The pattern obtained was that of total identify. The reactivity of SHPL, SHSL or NHSc was abolished by previous absorption with 2-aminoethylisothiouronium bromide-treated E. Anti-RS serum also did not react with the supernatant of heated cells such as HeLa cells and polymorphonuclear leukocytes which do not have exposed E receptors.

Erythrocytes↗
PubMed1982

T and B lymphocytes in the aqueous humor of patients with uveitis.

Sixteen patients with different types of uveitis (ocular toxoplasmosis, chronic cyclitis, Vogt-Koyanagi-Harada syndrome, Behçet's syndrome, ocular herpes, and a probable nematode) had the aqueous humor withdrawn and had the number of T, B, and null lymphocytes assessed. T and B lymphocytes were identified by rosette formation with sheep erythrocytes and with human erythrocytes sensitized with IgM antibody and complement or zymosan-C3 complexes, respectively. A much higher number of T lymphocytes than B lymphocytes was observed in all cases. The results were not influenced by treatment with steroids or immunosuppressive drugs for local, periocular, or systemic effects.

Aqueous Humor↗
PubMed1981

HLA antigens in Tükuna Indians.

Ninety-nine Tükuna Indians, inhabitants of the high Amazon, were typed for the HLA antigens. The method used was the microlymphocytotoxicity technique recommended by the NIH. At the same time, cross-matching was performed between the lymphocytes of the 99 Indians and the sera of 240 other multiparous Indians. Later the multiparous sera were cross-matched with a selected panel of Caucasoid individuals. The results showed that the most frequent antigens for th HLA-A locus were A2, Aw24 and Aw31. As for the HLA-B locus, B5, Bw39 and B40 were most frequent. The haplotypes HLA-Aw31-Bw39, and A2-B5 were in linkage disequilibrium. The results of the cross-matching showed 21.3% sera with positive reactions against Indian cells. Ten sera presented antibodies against known HLA antigens; five of them were monospecific, four had two specificities, and one showed three specificities. It was not possible to arrive at any conclusion about the 41 remaining sera. Six sera had positive reactions only with Indians cells.

Brazil↗
PubMed1980

Expression of HLA-DR antigens on T lymphocytes.

Our data have demonstrated, for the first time, expression of HLA-DR antigens on heated T cells (45 degrees C, 1 h) and have confirmed the occurrence of these antigens on mitogen-stimulated T cells. HLA-DR antigens were detected by microlymphocytotoxicity employing defined and non-defined anti-HLA-DR sera. The HLA-DR T cell antigens proved to be the same as the ones expressed on B cells from the same donor. In addition, extra reactions were observed on mitogen-stimulated and on heated T cells which could be abolished by absorption with cytotoxicity negative B cells of the same donor (cytotoxicity-negative-absorption-positive phenomenon).

Absorption↗
PubMed1980

Identification of T and B lymphocytes in the human conjunctiva and lacrimal gland in ocular diseases.

The presence and localisation of T and B lymphocytes in biopsy specimens of human conjunctiva and lacrimal gland from 34 patients were studied in frozen sections. Eighteen patients had follicular conjunctivitis, 13 patients had Sjögren's syndrome, and 3 were normal. All cases of follicular conjunctivitis showed a similar picture. B cells were in higher number than T cells, but both types of lymphocytes were present in the infiltrates. In the developed follicles T cells occupied the periphery and B cells the central part of the infiltrates. In patients with Sjögren's syndrome the conjunctival biopsies showed a higher number of B lymphocytes. The number of T cells was higher in the lesions from Sjögren's syndrome than in cases of follicular conjunctivitis. The infiltrate in lacrimal gland biopsies showed T cells which were scattered while B cells were more numerous and formed clusters close to vessels. Normal conjunctiva and lacrimal gland showed no adherence of either sheep erythrocytes or human erythrocytes sensitised with antibody and complement.

B-Lymphocytes↗
PubMed1979

Serum amyloid protein SAA, C-reactive protein and lysozyme in leprosy.

Serum amyloid protein (SAA) appears to be the precursor of amyloid protein AA, the non-immunoglobulin fibril protein of secondary amyloidosis. Since amyloidosis is known to occur in high frequency associated with lepromatous leprosy (LL), we have examined the SAA levels in untreated LL patients and compared them to the levels observed in patients with tuberculoid leprosy (TT) and a large number observed in healthy controls. We found that SAA is markedly elevated in LL when compared to TT and controls. No clear correlation could be established with C-reactive protein, a well-documented acute phase reactant, or serum lysozyme levels that reflect the presence of monocyte activity. This study showed that SAA levels in leprosy do not appear to be a reflection of inflammatory activity or monocyte turnover. Whether amyloidosis will be more prevalent in patients who have higher SAA levels remains to be determined.

Amyloid↗
PubMed1978

Cellular immunity in squamous cell carcinoma of the uterine cervix.

The thymus-dependent immunity of 42 patients with SCCC was evaluated by: delayed cutaneous reactions to ubiquitous antigens, DNCB sensitization, and lymphocyte response to PHA. In addition, T and B lymphocytes were detected in peripheral blood and in tumor sections, by adherence to E and HEAC. Depressed CMI was more intense in patients with disseminated disease, although a premature impairment of CMI was observed in some patients with initial-stage tumors. The absolute number of peripheral T lymphocytes showed association with both cutaneous reactions and PHA response. However, there appeared to be no significant correlation between the stage of the tumor and the pattern of adherence of E or HEAC to the biopsies.

Adult↗
PubMed1978

Monocyte function in patients with solid neoplasms during immunotherapy with Corynebacterium parvum.

The present studies were performed in order to evaluate monocyte function in patients with solid neoplasms before and after administration of C. parvum. The results demonstrate that monocytes from cancer patients display increased numbers of C3 and Fc receptor sites after administration of C. parvum. It is concluded that characterization of monocyte receptor activity may be helpful in monitoring the effects of immunotherapy in the immune system.

Chemotaxis, Leukocyte↗