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Biomedical subjects

S Ferrone

Publications and source records attributed to S Ferrone.

At least 469 records · Page 26Linked to original sources
PubMed1976

Isolation of human T and B lymphocytes by rosette formation with 2-aminoethylisothiquronium bromide (AET) -treated sheep red blood cells with monkey red blood cells.

Purified human B and T lymphocytes were obtained by rosetting HPL with AET-SRBC or MRBC and separating the non-rosetted from the rosetted cells on Ficoll-Hypaque gradient. 92 +/- 5% of the B cells were fluorescent positive for mBlg and 95 +/- 2% of the purified T cells rosetted with AET-SRBC. 69 +/- 5% of the B cells and 61 +/- 8% of the T cells present in the unifractionated HPL were recovered in the purified fractions.

Animals↗
PubMed1976

Comparison of histocompatibility antigens on cultured human tumor cells and fibroblasts by quantitative antibody absorption and sensitivity to cell-mediated cytotoxicity.

Human tumor and febroblast tissue culture cells were compared to determine the suitability of fibroblasts as control cells in experiments on human tumor serology and cellular immunology. Fibroblasts expressed the same HL-A antigen profile as did melanoma cells. Furthermore, the quantitative expression of the determinants was similar on both cell types. In four of five pairs tested, the fibroblasts displayed similar sensitivity to effector cells generated by mixed lymphocyte culture as did the tumor cells from the same donor, but there were some differences in the effects of specific alloimmune effector cells at high and low effector-to-target ratios on the two types of target cells. Results indicated that fibroblasts are legitimate control target cells for studies in human tumor immunology, if screening assays are done to verify their antigenicity and sensitivity to cell-mediated cytolysis.

Antigen-Antibody Reactions↗
PubMed1976

Natural antibodies to human lymphocytes in murine strains.

Murine strains vary greatly in their content of natural antibodies to human lymphocytes; sera from NZB, B10.BR/TSn, DBA/J, and B10.S mice reacted with more than 90% of the panel of human lymphocytes, yet those from other strains did not react. These levels of natural antibodies to human lymphocytes did not correlate with the H-2 type of mice, but appeared to be a dominant character with incomplete penetrance. Since sera from germfree mice also contained natural antibodies to human lymphocytes, their formation was not influenced substantially by bacteria.

Animals↗
PubMed1976

Humoral sensitization in parous women: cytotoxic antibodies to non HL-A antigens.

From sera of parous women, we selected 100 samples that lacked cytotoxic antibodies to human peripheral lymphocytes from at least 80 unrelated persons. These sera were then reacted with a panel of 17 cultured human lymphoid cells in the complement-dependent cytotoxic test. Forty-six sera contained cytotoxic antibodies apparently directed to an antigenic system distinct from HL-A antigens, and other known cell surface markers. Rabbit serum was the most efficient source of complement with these cytotoxic antibodies which did not appear to be directed to tumor associated antigens: in fact, no lysis of melanoma cells or leukemic cells could be detected. Ten specificities could be identified which were represented on the cultured human lymphoid cells in various combinations. It is suggested that antigens detected by this approach may be similar to the Ia antigens of the mouse.

Antibody Formation↗
PubMed1976

Inhibition of T-lymphocyte rosetting by HL-A alloantisera and complement.

The relationship between HL-A antigens and rosetting of sheep red blood cells (SRBC) with peripheral human lymphocytes has been investigated by incubating them with HL-A antibodies. Although sensitizing the lymphocytes with HL-A alloantisera had no effect on their ability to form rosettes with SRBC, further sensitization with C6 deficient rabbit serum as a source of early complement components inhibited the formation of rosettes with SRBC. The involvement of HL-A alloantibodies in the inhibition of rosette formation was shown first by correlating the HL-A phenotype of the lymphocytes and the HL-A specificity of the alloantisera and, second, by specifically absorbing the HL-A alloantibodies from the alloantisera. Complement was needed to inhibit rosette formation since this effect was lost when rabbit serum was treated to inactivate complement. The participation of complement's classical pathway in rosette inhibition was shown by chelating the Ca2+ ions by EGTA treatment of the C6 deficient rabbit serum. Perhaps, binding of HL-A antibodies and early complement components to the lymphocyte surface disturbs the distribution of the receptors or affects the charge of the cell membrane, thus inhibiting the rosette formation with SRBC.

Antigen-Antibody Reactions↗
PubMed1976

Characterization of Ia antigens in mouse serum.

Sera obtained from normal B10.BR mice were shown to inhibit selectively a specific anti-Ia alloantiserum. Partial purification of the Ia antigenic activity was accomplished by isolation of the high density lipoproteins from these sera by fractional precipitation with sodium phosphotungstate and MgCL2. Both H-2.23 and Iak antigens present in this high density lipoprotein fraction were completely adsorbed by rabbit anit-rat beta2-microglobulin immunoadsorbents, whereas specific anti-H-2.23 immunoadsorbents removed only the H-2 activity. These data deomnstrate that Ia antigens, like H-2 antigens in the sera of B10.BR mice are associated with high density lipoproteins and further suggest that both H-2 and Ia antigens are associated with a beta2-microglobulin-like molecule.

Animals↗
PubMed1975

Soluble HL-A antigens in serum. I. Isolation and purification.

A new method was developed which utilizes fractional salting out, gel filtration, ion exchange chromatography and polyacrylamide gel electrophoresis for the isolation and purification of soluble HL-A antigens from serum. The method produced purified antigens possessing HL-A 5,9 specificities with yield up to 60% of that detected in the original serum. Up to 150-fold increase in specific HL-A antigenic activity above that in the starting material could be achieved as measured by the ability of the purified antigens to specifically inhibit the cytotoxic activity of HL-A alloantisera against selected target cells. Electrophoretically purified HL-A antigens with different specificities appear to have a similar molecular size, i.e. 33 000, but differ in their electric charge properties, beta2-microglobulin (beta2m) seems to be noncovalently associated with HL-A antigens present in serum, but during purification beta2m in progressively lost until at the final purification by polyacrylamide gel electrophoresis, the material is completely devoid of beta2m.

Chemical Precipitation↗
PubMed1975

Production of anti-W24 xenoantisera in rabbits.

One out of four rabbits injected with partially purified soluble HL-A antigen from serum produced cytotoxic antibodies to human lymphocytes. These antibodies appear to be directed to the specificity W24 as determined by correlation studies with HL-A alloantisera and by absorption-inhibition experiments with human platelets and with serum soluble HL-A antigens. In the sera from the other three immunized rabbits, no antibodies to human lymphoid cells could be detected by the cytotoxic test, blocking of T cell rosette formation, stimulation of DNA synthesis and inhibition of mixed lymphocyte reaction.

Animals↗
PubMed1975

Utilization of cultured human lymphoid cells for detection of humoral sensitization in prospective recipients of kidney transplants.

Prospective recipients of kidney transplants were tested for lymphocytotoxicity; from these we selected 102 sera that lacked cytotoxic antibodies against peripheral lymphocytes from at least 80 unrelated subjects. To detect humoral sensitization, we then reacted these with 17 cultured human lymphoid cell lines having different HL-A phenotypes. Cytotoxic antibodies reacting with these cultured cells were now detected in some of the sera. These antibodies were not directed against HL-A antigens, yet mediated lysis of target cells in the presence of rabbit but not of human or guinea pig complement. Furthermore, they activated the classical pathway of the rabbit complement system. Later, a significant association was found between occurrence of cytotoxic antibodies and rejection of the transplant. Thus, cultured human lymphoid cells, because of their great susceptibility to complement-mediated lysis, appear to be useful in detecting humoral sensitization in candidates for kidney grafts.

Antibody Formation↗
PubMed1975

Distinction between malignant L cells and normal mouse fibroblasts by rosette formation with sheep red blood cells.

Murine L cell fibroblasts, and derivatives were found to rosette with sheep red blood cells (SRBC). Primary fibroblast explants from the parent murine strain, C3H, did not possess this potential. No rosettes were observed with primary fibroblast explants from C57BL and B10Br mice, with a human fetal lung fibroblast, with baby hamster fibroblasts or their polyoma transormed derivative, or with a cell line, 1T-22, derived from BALB/c mice. Hybridization of 1T-22 and L cells, by Sendai virus-mediated cell fusion, suppressed the rosette potential of the L cell parent. The receptor for SRBC on L cells appears to result from the expression of a recessive characteristic.

Animals↗
PubMed1975

Rosette formation of human lymphoid cells with monkey red blood cells.

Studies of human peripheral lymphocytes (HPL) from healthy subjects and of human lymphoblastoid cell lines (HLC) revealed spontaneous formation of rosettes with Macaca speciosa monkey red blood cells (MRBC). The percentage of HPL forming rosettes with MRBC paralleled the percentage of HPL exhibiting markers ascribed to human B cells. The MRBC-rosetting cells were positive for membrane-bound immunoglobulin (MBIg). Furthermore, by employing a mixed rosette method, lymphocytes carrying both EAC3dmo and FITC-MRBC were encountered. In contrast, no lymphocytes carrying both SRBC and FITC-MRBC were observed. Ninety-six per cent of purified B cells obtained at the interface after interaction of HPL with SRBC and Ficoll-Isopaque centrifugation formed rosettes with MRBC. In contrast, only 8% of an enriched population of T cells obtained at the interface after interaction with EAC3dmo and Ficoll-Isopaque centrifugation formed MRBC-rosettes. Incubation of HPL with MRBC and subsequent centrifugation on Ficoll-Isopaque resulted in a highly enriched T cell population at the interface. Several lymphoblastoid cell lines with B cell characteristics, but not two cell lines with T cell characteristics, formed spontaneous rosettes with MRBC. Inhibition experiments showed that the structure on the lymphoid cell surfaces mediating the adherence of MRBC was independent of the MBIg as well as the recptors for IgGFc, C3b, and C3d. It appears that rosetting with MRBC will provide a new detection marker for human cells classified as B type and a technique for obtaining an enriched T cell population.

Animals↗