Search PubMed⌕ Search

Biomedical subjects

G B Ferrara

Publications and source records attributed to G B Ferrara.

At least 109 records · Page 6Linked to original sources
PubMed1987

Human lymphoblastoid cell lines secreting antibodies with restricted HLA specificity.

Peripheral B lymphocytes obtained from three healthy individuals who had been immunized against peripheral blood lymphocytes from appropriate HLA-incompatible donors were transformed by the use of Epstein-Barr virus. The transformed blastoid B cells were repeatedly subcultured by means of "cluster picking," and the HLA antibody-producing cultures were identified by testing the culture supernatants by means of the cytotoxicity assay, using the corresponding donor cells. Thus far, four cell lines that secrete cytotoxic HLA antibodies (MP1, 3, 4, and 5) have been established. Specific immunoabsorption experiments revealed that the antibody activity is carried by lambda-type IgM for MP1, by kappa-type IgM for MP3 and MP5, and by both for MP4. Specificity analysis of a panel of HLA-pretyped cells indicated that MP1 detects DQw2, whereas MP5 recognizes B7. The specificity of MP3 was similar to a DQ specificity termed DC5 (probably equivalent to TA10) but not the same. In the case of MP4, both of the lambda-type and kappa-type antibodies appeared to be directed toward new HLA class II determinants.

Antibody Specificity↗
PubMed1987

DNA typing of HLA-DR beta chain genes can discriminate between undetected alleles and real homozygotes.

The polymorphism of HLA-DR antigens has been studied by Southern blot hybridization under conditions specific for the detection of the DR beta chain genes. Haplotype-specific patterns were defined with DNA from DR1, 2, 3, 4, 7, w8, w11, w12, and W13 homozygous typing cells, with restriction enzymes Eco RI, Bgl I, and Pvu II. Certain serological specificities, such as DR2, DR3, and DR7, can be encoded by distinct allelic forms of DR beta chain genes. The procedure of "DNA typing" was applied to family analysis of individuals expressing only a single DR specificity upon serological typing. Three cases are described here: (1) in family GR, phenotypic DR 7 homozygotes correspond to genomic heterozygotes, and a novel DR7 allele is described: (2) in family RU, the genes corresponding to a serologically undetected (blank) DR allele were identified by restriction fragment length polymorphism (RFLP); this novel DR haplotype has an RFLP pattern similar to those of the DRw52 family, even though this specificity was not expressed on the DR-blank lymphocytes; (3) in family RG, there is no blank allele, but a homozygote RFLP situation at the DR subregion.

Alleles↗
PubMed1987

Occurrence of lymphocyte proliferative response to thyroglobulin and antithyroglobulin antibodies in normal individuals: lack of correlation with HLA.

Peripheral mononuclear cells (MNC) of patients with autoimmune thyroid disease have been shown to proliferate when cultured with human thyroglobulin (hTg). In addition, such a phenomenon is apparent in a certain number of healthy individuals. In this study we have attempted to correlate hTg-induced MNC proliferation, occurrence of anti-hTg autoantibodies and HLA phenotype (including Class II DR and DQ loci) in a population of HLA-typed normal blood donors. Fourteen out of 56 subjects showed a significant MNC proliferation to hTg. Three of them had anti-hTg autoantibodies in the serum, while none of the hTg-unresponsive subjects showed such antibodies. No correlation with HLA phenotype (including Class II DR5 specificity, referred as associated with Hashimoto's thyroiditis, and DQ alleles) was observed.

Adult↗
PubMed1987

A human monoclonal antibody against HLA-A25.

We are reporting the production and characterization of a human monoclonal antibody recognizing antigen HLA-25. The antibody was developed by a line transformed in vitro by the Epstein-Barr virus. The immune B lymphocytes for transformation were generated by planned immunization of a volunteer with repeated doses of allogenic peripheral blood lymphocytes of one donor over the course of 7 years. The antibody showed correlation with A25 antigen on a panel of 244 individuals tested by microcytotoxicity. The antibody showed neither cytotoxic reactivity nor CYNAP phenomenon with antigens of HLA-10 CREG.

Antibodies, Monoclonal↗
PubMed1987

Correlation between steroid hormone receptors and prognostic factors in human breast cancer.

Knowledge of the tumor content of estrogen (ER) and progesterone (PgR) receptors has proved to be of significant value in human breast cancer. Relative determinations were performed in 589 specimens in our laboratory. The positivity of ER and PgR is correlated with the patients' age at diagnosis, tumor size and relative grade. In particular, the significance of PgR versus ER status and the possible prognostic role of these receptors are investigated.

Adult↗
PubMed1986

Subset analysis of human class II molecules controlled by the DR2/Dw2 haplotype: two separate DR subsets carry the DR2 specificity.

Human class II molecules were isolated from cells of a DR2/Dw2-homozygous cell line, PGF. The three mutually exclusive subsets were separated by selective binding with monoclonal antibody MCS7 and alloantisera CCB921 and KY22. The specificity involved in the binding with alloantisera was identified to be a supertypic specificity associated with DR1, 2, and w9 for CCB921 and the DQw1 specificity known to be associated with DR1, 2, w6, and w10 for KY22. The MCS7 specificity appeared to be a cross-reactive specificity related to the DRw52-like specificity. On peptide mapping, the alpha chains of MCS7- and CCB921-reactive subsets were the same, showing the pattern characteristic of DR alpha chains, whereas the beta chains were very similar to, but distinguishable from, each other. These structural features conformed to those of DR or DR-like subsets. The KY22-reactive subset was distinctive in both alpha and beta chains from the above two subsets, and it displayed peptide patterns typical to DQw1-bearing Ia molecules. Interestingly, the MCS7- and CCB921-reactive subsets both carried the DR2 specificity, as indicated by their binding to alloantiserum Fe73/22 which was proven to be DR2-specific.

Alleles↗
PubMed1986

Serological discrimination of DR4 haplotypes by radioimmunoassay.

Three new alloantigenic specificities of human major histocompatibility complex class II molecules have been defined by testing the reactivity of alloantisera at the molecular level. Two of these specificities identify different DR4 haplotypes. The Fe75 specificity is associated with the DR4/Dw10 haplotype and the CBC/MRG6 specificity with the DR4/DKT2 haplotype. Both are supertypic specificities and are associated with other DR specificities as well. Both specificities are carried by class II molecules belonging to the first DR subset. Together with previously described determinants, these specificities contribute to serological discrimination of the different DR4 haplotypes.

Antibody Specificity↗
PubMed1986

In vitro production of a human HLA alloantibody of restricted specificity (DQw2) via Epstein-Barr virus transformation.

This paper describes the in vitro production of the human alloantibody 454A.C5 with HLA-DQw2 specificity produced by a stable EBV-transformed cell line. Immune B cells for transformation were generated by planned immunization of a blood donor volunteer with repeated HLA-immunizations over the course of 9 yr. Reactivity of 454A.C5 was in exact concordance with the presence of the DQw2 antigen as defined by microcytotoxicity assay on a panel of 21 B lymphoblastoid cell lines with well-characterized HLA antigens. Family studies showed the segregation according to the HLA-DQw2 haplotype; thus we demonstrate by serological and formal genetics criteria, that the alloantibody is specifically directed against the DQw2. 454A.C5 antibody may be employed as a monospecific HLA typing reagent.

Antibody Formation↗
PubMed1985

A new allodeterminant on HLA-DQ molecules carrying the DQw3 specificity.

The la subset that reacts with alloantiserum HON known to possess a strong anti-DRw53 activity was isolated from a 125I-labeled Ia preparation obtained from cells of RPMI 8057 cell line (DR1,4) and was found on peptide mapping to be lacking in the pattern characteristic of DR-like molecules carrying the DRw53 specificity and to display the structural features of DQ molecules, particularly those carrying the DQw3 specificity. Distribution analysis on a panel of selected la-positive cell lines indicated that the specificity involved is associated only with DR4 and DRw9, differing from the known DRw53 pattern (DR4, 7, and w9) and also from the known DQw3 pattern (DR4 and 5). Reciprocal sequential binding experiments demonstrated that the HON-defined specificity resides along with DQw3 specificity on the same molecules. Thus, HON alloantiserum possesses two different antibody activities; one directed to DRw53 specificity and another directed to a new DR4- and w9-associated DQ specificity.

Epitopes↗
PubMed1985

DR5-associated DC molecules carry three different allospecificities.

Antiserum 8w670 which had been classified as anti-DR5 in the Workshop analysis was found by the direct binding test to react with about 40% of Ia molecules in an Ia preparation from LG38 cells (DR5,5) that was deleted of DR molecules and DR-like molecules we call BR and enriched in DC molecules by pretreatment with a rabbit antiserum raised against alpha-subunits of DR and BR molecules. The specificity involved in the binding reaction was shown by the binding inhibition assay to be present in 100% of DR5-positive cases (53 out of 53) and 8w13-positive cases (2 out of 2) and in 23% of DR4-positive cases (4 out of 17). This association pattern did not correspond to any of the known supertypic specificities including the DC beta 4 and DC alpha 3, both of which had been found on DR5-associated DC molecules. Yet sequential binding analysis revealed that the 8w670-defined specificity was indeed present on the same molecules carrying DC beta 4 and DC alpha 3 specificities. This specificity was designated DC5.

Antibody Specificity↗
PubMed1985

Preoperative carcinoembryonic antigen and prognosis in patients with colorectal cancer.

The relationship between preoperative CEA, Dukes staging and disease recurrence, was analyzed in 92 patients with colon-rectal cancer, all who underwent curative surgery. Sixty-five of the 92 patients were followed for 36 months. A significant increase in disease recurrence risk is observable starting from a preoperative CEA value of greater than 7.5 ng/ml; corresponding values as such are verified by a significant fall in the actuarial survival curve in comparison to the progress of the curves of the other two groups with lower CEA values. A statistically significant correlation between preoperative CEA and staging was not observed, while both parameters result statistically very reliable (p less than 0.001) for prognosis; preoperative CEA values, less or greater than 7.5 ng/ml can help to stratify the Dukes tumours with respect to the probability of recurrence.

Adenocarcinoma↗
PubMed1984

Evaluation of a new tumor-associated antigen in pancreatic cancer.

This study was carried out to assess the diagnostic accuracy of a new gastrointestinal cancer antigen ( GICA ) defined by a monoclonal antibody. Its sensitivity and specificity were assayed in a group of patients with different pancreatic diseases (10 acute pancreatitis, 27 chronic pancreatitis, 22 cancers of the pancreas) and in 29 normal individuals. The concentration of GICA was always inferior to 37 units/ml (our discriminant limit between cancer and noncancer patients) both in cases with chronic pancreatitis and in healthy subjects. Increased levels of the antigen were found in 16/22 (72.7%) pancreatic cancer patients and in 3/10 (33.3%) cases with acute pancreatitis. The assay was within the normal range in 2 (28.6%) out of 7 cancers judged resectable. The test is simple and rapid, but its relative sensitivity and the frequent elevation of GICA in other adenocarcinomas of the gastrointestinal tract make it unsuitable for screening programs in pancreatic cancer. Even its use for early diagnosis of cancer of the pancreas does not seem promising. The major finding of our study is the lack of false-positives in patients with chronic pancreatitis and therefore the usefulness of this test in differentiating preoperatively between chronic inflammation and cancer of the gland. Frequent increase of the marker in patients with acute pancreatitis is not yet clear.

Adenocarcinoma↗