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G C Faure

Publications and source records attributed to G C Faure.

At least 91 records · Page 5Linked to original sources
PubMed1992

Peripheral blood specific antibody-forming cells after oral stimulation with a ribosomal vaccine.

A double-blind study was performed in 12 healthy volunteers in order to determine whether circulating immunocytes are present after oral immunization. Sequential samples of peripheral blood were collected at various times after ingestion of a ribosome vaccine (D53) or placebo. Immunoglobulin-containing cells were identified in immunofluorescence and specific antibody-forming cells were detected in agarose ELISA-spot. Higher numbers of both types of cells were observed in the group of individuals receiving ribosomal extracts. An open study allowed a better approach to the kinetics of this phenomenon, related to the release of activated B-cells from Peyer's patches upon antigenic stimulation. This methodological approach has been described in animal models but seldom reported in humans.

Administration, Oral↗
PubMed1992

[Peripheral blood cells secreting specific antibodies after oral stimulation with a ribosomal vaccine].

This investigation was designed to investigate mechanisms underlying oral immunization in humans after ingestion of the ribosomal vaccine D53. Immunofluorescence and ELISA (Enzyme-Linked ImmunoSorbent Assay) spot techniques were used for peripheral blood studies. The first part of the investigation was a double-blind placebo-controlled study of 12 healthy volunteers; counts of cells containing immunoglobulins and cells producing specific antibodies were higher in the individuals given the oral ribosomal vaccine than in the placebo-treated controls. In the second part of the investigation, analysis of the kinetics of apparition of the immunoglobulin-containing and specific antibody-producing cells suggested prompt stimulation of Peyer patch B lymphocytes following ingestion of the vaccine. Lastly, a study of 5 children given the vaccine on a long-term basis demonstrated increased counts of both above-described cell types after one month treatment.

Administration, Oral↗
PubMed1992

Sequential assay of human milk immunoglobulins shows a predominance of lambda chains.

BACKGROUND: Little is known of the light chains associated to heavy chains in secretions immunoglobulins. We investigated the partition of light chains in a mucosal fluid of easy access and major physiologic importance: human milk. EXPERIMENTAL DESIGN: This study provides a sequential analysis of IgA, lambda and kappa chains levels in human milk during the first days of lactation. The levels of IgA alpha-chain and of lambda and kappa light chains of immunoglobulins were assayed in 162 samples of normal human milk collected during the first night of lactation, using a classical immunonephelometric assay. A specific enzyme-linked immunosorbent assay was developed to specifically measure the levels of IgA-linked light chains, yielding similar values. Ten samples of normal human serum obtained from healthy adults were tested in parallel. RESULTS: The highest levels were observed during the first 3 days of lactation, and a plateau appeared for the three proteins after day 4. Mean lambda chains levels were consistently higher than these of kappa chains, resulting in a reversed kappa/lambda ratio, significantly different from the classical 2:1 serum ratio confirmed with this method on control samples. CONCLUSIONS: This study indicates that milk immunoglobulins use an unusual partition of light chains, especially in IgA.

Humans↗
PubMed1991

Immunohistologic analysis of the cholesteatoma matrix in children.

The immunohistological characteristics of retraction pockets, cholesteatoma matrix and granulomatous tissue were compared in 14 samples from pediatric cholesteatoma. The junction between epidermis and the middle ear mucosa appeared as the most inflammatory area, displaying the characteristics of delayed type hypersensitivity. CD1 + Langerhans cells were observed in all epidermic areas, but expressed class II molecules only in the vicinity of polymorphonuclear infiltrates. Numerous mast cells and IgA producing cells were also observed, suggesting that defenses from the mucosal immune system are summoned and contribute to the pathogenesis of cholesteatoma.

Adolescent↗
PubMed1991

Confirmation of tonsillar anomalies in IgA nephropathy: a multicenter study.

Tonsillar abnormalities have previously been evidenced in IgA nephropathy (IgAN). We report the results of a systematic quantitative analysis of 303 tonsils obtained in 70 IgAN patients and 142 controls. IgG- and IgA-producing plasma cells, stained by immunofluorescence, were enumerated on serial sections of all samples. Both the percentage and number of IgA+ cells were significantly increased in IgAN patients. This anomaly was also observed in age- or sex-matched subgroups of patients. Performed on a large series of individuals this study confirms the dysregulation of IgA production the upper respiratory tract of IgAN patients.

Adolescent↗
PubMed1991

Alternative rearrangements of immunoglobulin light chain genes in human leukemia.

Immunoglobulin heavy and light chain genes undergo rearrangement before they can be expressed by B-cells. A sequence of successive rearrangements has been proposed, suggesting that these events are initiated on heavy chain genes and are followed by sequential attempts of light chain gene rearrangements involving kappa gene alleles before lambda genes. This hypothesis, mainly established on B-cell clones of medullary origin, is consistent with the predominance of kappa chains among human serum immunoglobulins. However, data from tumors or normal lymphoid tissue suggest that lambda chain expression could be favored outside the bone marrow, due to an alternative rearrangement hierarchy. We investigated this hypothesis further on 17 leukemia samples. In three instances, we observed that lambda genes had undergone rearrangement while kappa genes remained in germline configuration. These data support the hypothesis of occasional alternative rearrangements of light chain genes.

Antigens, CD↗
PubMed1991

[New concepts of the course of cholesteatoma from the immunohistological study of 96 samples].

The immunohistological characteristics of retraction pockets, cholesteatoma matrix and granulomatous tissue have been compared. Langerhans cells, epidemic folds and sub-epithelial tissue were labelled with specific markers (HLA II, adhesion receptors, KI 67). The junction between epidermis and sub-epithelial tissue of middle ear mucosa appeared as the most inflammatory area, displaying characteristics of delayed type hypersensitivity phenomenon. CD1+ Langerhans cells appear to express class II molecules only in the vicinity of polymorphonuclear infiltrates. Epidemic proliferation seems to able place mainly in the deepest recesses of the epidermis.

Acute Disease↗
PubMed1990

Pre-B lymphocytes with intracytoplasmic mu chains in the peripheral blood of rheumatoid arthritis patients.

A dysregulation of B-cell differentiation and activation has long been evidenced in rheumatoid arthritis (RA). Such analyses have, however, usually focused on the latest stages of B-cell development. Using a classical technique of immunofluorescence labeling on cytospins, we investigated the presence of peripheral pre-B lymphocytes in 92 RA patients and 23 controls. Cells with intracytoplasmic mu chains were evidenced in 58.7% of the RA patients studied, ranging between 0 and 30%, while small numbers of c-mu cells, never exceeding 6% of peripheral blood lymphocytes, were observed in 9 controls. Relationships between this feature and clinical or laboratory data were investigated, showing a negative correlation between the percentage of c-mu + lymphocytes and Ritchie's index (P = 0.05), the number of tender or swollen joints (P = 0.05), erythrocyte sedimentation rate (P = 0.005), seropositivity (P = 0.05), and disease duration (P = 0.01).

Adult↗
PubMed1990

Increase in specific antibody-forming cells in human tonsils after oral stimulation with D-53, a ribosomal vaccine.

Thirty subjects who had received an oral ribosomal vaccine to common bacteria of upper respiratory tract infections, and ten controls were tonsillectomized for recurrent infections or rhonchologic pathology. A three-step indirect immunofluorescence technique was used to identify and enumerate specific antibody forming cells (SAFC) in their tonsils. Plasma-cells specific of the four strains being constituents of the oral vaccine (H. influenzae, K. pneumoniae, S. pyogenes and S. pneumoniae) were observed in all samples. The numbers of SAFC were significantly higher in the subjects who had received the oral vaccine. These results support the efficiency or oral immunization in increasing local defenses, even at distance from the sensitized gut-associated lymphoid tissue. These data provide evidence for the homing phenomenon in human mucosae associated lymphoid tissue (MALT).

Adolescent↗
PubMed1990

Plasma cells producing lambda light chains are predominant in human gut and tonsils. An immunohistomorphometric study.

An immunohistomorphometric study was performed on human samples of duodenum (10) and tonsil (25) to assess the numbers of plasma cells producing kappa or lambda chains. Different reagents were used and carefully assayed for specificity and absence of cross-reactivity. Kappa chains were found predominantly with these antibodies in 46 bone marrow-derived B-cell proliferations used as reagents' control samples. In contrast, plasma cells producing lambda chains were found to be more numerous in the samples of mucosal tissues. The kappa/lambda ratio observed was 0.53. This finding could be another feature reflecting the autonomy of the immune system of mucosae (MALT) in humans.

Adolescent↗
PubMed1990

A CD4-like molecule can be expressed in vivo in human parathyroid.

The expression of several epitopes of CD4, a molecule usually restricted to a subset of T-lymphocytes, was observed after immunofluorescent labeling of frozen-cut sections of human parathyroid. Seven samples obtained from three subjects presenting adenomas and from seven renal insufficiency patients with secondary or tertiary hyperplasia were found to express this molecule. Dot enzyme-linked immunosorbent assay, polyacrylamide gel electrophoresis, and Western blotting were used to characterize this peptide in cytosol and membrane fractions of these glands. These studies confirmed, in the parathyroids found positive in immunofluorescence, the presence of a protein with a mol wt similar to that of lymphocyte-derived CD4.

Adult↗
PubMed1989

Correlations between acute lymphoid leukemia (ALL) immunophenotype and clinical and laboratory data at presentation. A study of 350 patients.

The phenotypes of malignant cells from 350 untreated patients with acute lymphoblastic leukemia (ALL) were determined at diagnosis with the use of a panel of monoclonal antibodies to leukocyte antigens. According to the phenotypes seen, the cases were divided into five groups, pre-B ALL, B-ALL, T-ALL, MO-ALL, and undifferentiated ALL. Each group was subdivided, resulting in 11 defined immunologic subtypes. Correlations between clinical and laboratory features were investigated at presentation. ALL of early-B phenotype associated with elevated cell counts occurred more often in female and infant patients than in male patients. Involvement of the central nervous system was frequent in B-ALL, which occurred mostly in male patients. A male prevalence was also seen in ALL of T-lineage in which significant differences regarding clinical characteristics and leukocyte counts appeared among the four subtypes. The clinical relevance of phenotypic subcategorization is supported by our observations.

Antibodies, Monoclonal↗
PubMed1989

Investigation of the CD10 (cALLA) negative acute lymphoblastic leukaemia: further description of a group with a poor prognosis. French Groupe d'Etude Immunologique des Leucémies.

The absence of CD10 (cALLA) in non-T non-B acute lymphoblastic leukaemia (ALL) is usually considered to be of adverse prognostic significance. From a large multicentre series of phenotyped ALL, we have identified a group of 23 non-T non-B ALL where blast cells were CD10 negative and CD19 positive. Class II antigens were present in 80% and C19 in 70%. Eight patients had successful karyotype analysis at diagnosis, and an additional patient at first relapse. Seven of these karyotypes showed a (4;11) (q21;q23) translocation. Most of the patients (70%) were young females, and they often presented with organomegaly. Six patients were less than 1 year old. The white cell count was over 100 x 10(9)/l in 48% of the cases. The FAB type was L2 in 56% of the patients. The most striking features were the poor response to therapy and survival. Six patients never attained complete remission and nine patients relapsed, most of them during the first year after diagnosis. Allogeneic bone marrow transplantation was performed in three children, of whom two are still alive 2 years after diagnosis. This study emphasizes the prognostic value of immuno-phenotypic and karyotypic investigations of ALL.

Adolescent↗
PubMed1988

Mesangial IgA in IgA nephropathy arises from the mucosa.

Numerous studies have attempted to elucidate the pathogenetic mechanisms of IgA nephropathy, analyzing kidney, serum, lymphocytes, and lymphoid tissue of patients with this glomerulonephritis. Based on studies of the molecular characteristics of the mesangial IgA, clinical features, and immunologic analysis of the mucosal tissue, a wide array of findings suggest that mesangial IgA indeed arises from the mucosa. These three areas of research are discussed, as well as the hypothesis of a systemic origin for the mesangial IgA.

Glomerular Mesangium↗
PubMed1988

IgA nephropathy and alcoholic liver cirrhosis. A prospective necropsy study.

The incidence of mesangial IgA nephropathy (mIgAN) was investigated in a series of patients with alcoholic liver cirrhosis (ALC). Biologic parameters classically reported in IgAN were assessed in 98 patients, namely hematuria, proteinuria, and serum IgA. An immunohistologic study of the liver and kidney was performed in 33 patients who died during the study. Renal data were compared with those obtained in a matched necropsic series of controls. This study confirmed a global elevation of serum IgA levels in ALC. A possible hepatic origin of these immunoglobulins was supported by the observation of plasma cells in portal spaces in 68% of the patients. Biologic signs of renal disease consistent with mIgAN were observed in 16% of the patients; IgAN was diagnosed in 18% of patients with ALC and 10% of the controls. These data suggest that the incidence of mIgAN in ALC is not different than in the general population.

Adult↗