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M Geuna

Publications and source records attributed to M Geuna.

At least 37 records · Page 2Linked to original sources
PubMed1996

p53 expression and proliferative activity predict survival in non-invasive thymomas.

We performed p53 immunohistochemistry, DNA flow cytometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) in formalin-fixed, paraffin-embedded sections from 46 non-invasive thymomas and correlated the results with the traditional clinicopathologic features of the tumor. p53 immunopositivity was detected in 21 of 46 cases; it was not associated with any clinicopathologic features nor DNA content but significantly correlated with AgNOR counts. On univariate analysis, 10-year survival rates were 100% for p53-negative cases but only 71% for p53-positive cases and 93% for patients with low AgNOR counts but only 77% for patients with high AgNOR counts. Age, sex, histologic type, myasthenia gravis and DNA content did not correlate with survival. Our results indicate that p53 staining and evaluation of proliferative activity allow assessment of prognosis in non-invasive thymomas, when all of the other parameters are insufficient. Furthermore, the high rate of p53 expression in non-invasive thymomas suggests that abnormal p53 immunoreactivity may occur early in the neoplastic process.

Adolescent↗
PubMed1996

Systemic high-dose recombinant-alpha-2a-interferon therapy modulates lymphokine production in multiple sclerosis.

Chronic systemic high-dose recombinant alpha 2a-interferon (rIFNA) therapy reduces exacerbation rate and MRI signs of disease activity in relapsing/remitting multiple sclerosis (RR MS) patients. In order to clarify the possible mechanisms underlying the clinical efficacy of rIFNA in MS, several immunologic studies were performed as a part of a pilot clinical trial. Twenty RR MS patients were treated with 9 x 10(6) IU of rIFNA (n = 12) or placebo (n = 8) intramuscularly every other day for 6 months. Cytokine production by cultured lymphocytes, major histocompatibility complex class II (MHC-II) antigen expression on cultured macrophages, peripheral blood (PB) and cerebrospinal fluid (CSF) lymphocyte phenotype, and IgG and beta 2 microglobulin levels were studied before therapy, after 6 months of therapy, and 6 months after stopping therapy. rIFNA therapy was associated with reduction of interferon-gamma and tumor necrosis factor-alpha production by PB lymphocytes (p < 0.04), and with slight, not significant, increase of transforming growth factor-beta 2 or interleukin (IL)-10 production. IL-4 was undetectable in the culture supernatants both before and after therapy. rIFNA therapy had no effect on macrophage MHC-II molecule expression. An increased percentage of CD8+, CD8+ high CD11b+ low, and CD3- CD16+ CD56+ cells, and of CD4+ absolute cell number was observed in CSF after rIFNA therapy. After rIFNA administration, IgG level significantly increased both systemically (p < 0.02) and intrathecally (p < 0.001). Serum beta 2 microglobulin level increased (p < 0.01), as well. Only 1 out of the 12 rIFNA treated patients developed neutralizing antibodies against rIFNA during therapy. Six months after stopping therapy all the immunologic changes returned to baseline. These data suggest that the beneficial effect of rIFNA therapy on MS disease activity is probably mediated by a downregulation of proinflammatory cytokine synthesis by PB lymphocytes rather than by macrophage MHC-II antigen expression. The immunologic effects of high-dose systemic rIFNA therapy are temporary and restricted to the period of drug administration.

Antibodies↗
PubMed1996

DNA ploidy and p53 expression correlate with survival and cell proliferative activity in male breast carcinoma.

DNA flow cytometry and the monoclonal antibody DO7 were applied in formalin-fixed, paraffin-embedded specimens from 34 primary male breast carcinomas to verify whether DNA ploidy and p53 expression were associated with survival and proliferative activity. They were compared with tumor clinicopathologic features, sex steroid hormone receptors and cell proliferative activity, assessed by the counts of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody PC10 against the proliferating cell nuclear antigen and the monoclonal antibody MIB-1. A significant correlation was found between survival and tumor ploidy (median survival, 77 months for diploid but only 38 months for aneuploid cases; P = .03) and p53 expression (median survival, 95 months for cases with p53 scores < or = 14.06% versus 33 for cases with P53 scores > 14.06%; P = .0004; median survival, 99 months for p53 negative vs 39 for positive cases; P = .007). Tumor histological grade (P = .006), AgNOR counts (P = .0001), PC10 scores (P = .002), and MIB-1 scores (P = .001) were also associated with prognosis. In the multivariate analysis, only p53 scores (P = .001) or p53 immunopositivity (P = .003) and AgNOR counts (P = .022) retained an independent prognostic significance. Aneuploid tumors had higher AgNOR counts (P = .002), PC10 (P = .007), MIB-1 (P = .006), and p53 scores (P = .01) than diploid cases. A linear relationship was observed between p53 scores and AgNOR counts (r = .41; P = .014), PC10 (r = .46; P = .005), and MIB-1 scores (r = .44; P = .011). These results indicate that DNA ploidy and p53 expression are associated with survival and cell proliferative activity in male breast carcinoma. Quantitative parameters, such as DNA ploidy, p53 scores, AgNOR counts, PC10, and MIB-1 scores substantially improve the prognostic significance of the traditional parameters in male breast carcinoma.

Adult↗
PubMed1996

Prolactin increases the susceptibility of primary leukemia cells to NK and LAK effectors.

Our previous studies have shown that prolactin (PRL), a pituitary and lymphocyte hormone and a ligand of the cytokine/hemopoietin receptors (R) superfamily, acts synergistically with interleukin (IL)-2 on the development of lymphokine activated killer (LAK) cells and enhances the effects of GM-CSF and IL-3 on myeloid progenitors' proliferation and differentiation. More recently, we have demonstrated that GM-CSF and IL-3 increase the sensitivity of acute myeloid leukemic (AML) cells to LAK activity. Together, these findings have prompted us to study the role of PRL on the target arm of the LAK response. We show here that CD33+ blasts from AML patients express membrane PRL-R and that the PRL/PRL-R interaction is followed by increased susceptibility to natural killer (NK) (p < 0.02) and LAK (p < 0.001) cells. As predicted from the dimerization model of PRL-R and in agreement with previous reports, the response of AML blasts to PRL was bell-shaped with a trend peak at 25 ng/ml. Although enhanced lysis occurred at the target recognition level, it was not accompanied by changes in the MHC class I, cellular adhesion molecules, or myeloid differentiation antigens. Cell cycle recruitment and lysis increased concurrently in three cases studied, suggesting a modulatory action of PRL on the expression of putative cycle-related NK/LAK-target structures. Together, these data strengthen the role of PRL in the LAK response.

Adjuvants, Immunologic↗
PubMed1996

Interferon alpha-2a treatment of relapsing-remitting multiple sclerosis: disease activity resumes after stopping treatment.

We evaluated the long-lasting effects of systemic high-dose recombinant interferon alpha-2a (rIFNA) in relapsing-remitting (RR) MS after discontinuing treatment in a single-blind randomized placebo-controlled trial with 20 RR clinically definite MS patients using either nine million IU intramuscular rIFNA (n = 12) or placebo (n = 8) every other day for 6 months. Follow-up continued for a further 6 months without IFN treatment. In rIFNA-treated patients, main outcome measures, significantly different from placebo during treatment, returned, after discontinuing treatment, to values similar to placebo or baseline. Active MRI lesions per patient increased from 0.08 +/- 0.08 to 1.2 +/- 0.4 (p < 0.02), number of patients with clinical MRI signs of disease activity from 2 of 12 to 8 to 12 (P < 0.04), lymphocyte IFN gamma production from 3.0 +/- 0.7 to 12.4 +/- 2.2 IU/mL (p < 0.01), lymphocyte tumor necrosis factor alpha production from 5.8 +/- 0.9 to 18.9 +/- 6.3 pg/mL (p < 0.05). All side effects of rIFNA treatment disappeared after discontinuing the drug. The reduction of clinical MRI signs of disease activity and the immunologic effects were temporary and restricted to the period of rIFNA administration. The depression of many immunologic and clinical MRI responses during drug administration and their simultaneous return to baseline after discontinuing the drug strongly argue all observed changes were related to drug administration.

Adult↗
PubMed1995

Regulatory action of prolactin on the in vitro growth of CD34+ve human hemopoietic progenitor cells.

The pituitary hormone prolactin (Prl) is known to act as a local regulator of immune cell function, and Prl-binding receptors (Prl-R) have been described to share distinctive features with the members of the newly described cytokine/hemopoietin receptor superfamily. Here we show that the hormone can functionally interact with lineage-specific hemopoietic factors. When highly purified progenitor cells (CD34+ve) were seeded in semisolid methylcellulose cultures in the presence of interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), and erythropoietin (Epo), a selective enhancing effect of Prl on the formation of colony forming unit-granulocyte (CFU-G) and burst forming unit-erythroid (BFU-E) colonies was observed. The effect of the hormone was plotted as a bell shaped curve, with the optimal response at the supraphysiological concentration of 50 ng/ml. Limiting dilution analysis showed that Prl acted directly on hemopoietic progenitors. This was confirmed by the observation on the CD34+ve cells of Prl-binding sites reacting with the specific monoclonal antibodies (mAbs), U5 and PrR-7A. Immunoprecipitation of the metabolically labeled CD34+ve cells with the PrR-7A mAb revealed a structure of 43 kD under reducing conditions. Analysis of the early events associated with the Prl/Prl-R interaction showed an increased number of cells engaged in DNA and hemoglobin synthesis. Enhanced erythroid differentiation of CD34+ve cells in the presence of Prl was secondary to upmodulation of receptors for the lineage-specific factor Epo. Together these data demonstrate the existence of a functional interplay between Prl and hemopoietic factors.

Antibodies↗
PubMed1995

Isochromosome 6p and deletion of 6q characterize two related cytogenetic clones in a patient with immunoblastic lymphoma.

In a case of immunoblastic lymphoma we observed the presence of either a deletion of the long arm of chromosome 6 or of an isochromosome, i(6p), which occurred alternatively in metaphase cells. This suggests a selective pressure for loss of heterozygosity of genes located on 6q and is in accordance with the hypothesis that one or more tumor suppressor genes might be located on the long arm chromosome 6.

Aged↗
PubMed1995

Long-term survival of thymoma patients by histologic pattern and proliferative activity.

We performed DNA flow cytometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) in formalin-fixed, paraffin-embedded sections from 60 surgically resected thymomas. The results were correlated with histologic pattern, stage, associated clinical features, and survival to assess which parameters could best predict prognosis. On univariate analysis, the 10-year survival rates were 86% for predominantly lymphocytic type but only 42% for predominantly epithelial, mixed lymphoepithelial, or spindle cell thymomas (p = 0.006); survival rates were 85% for noninvasive but only 34% for invasive thymomas (p = 0.0002); 73% for diploid but only 38% for aneuploid cases (p = 0.005); 88% for thymomas with 5.75 AgNORs per cell or fewer but only 34% for thymomas with more than 5.75 AgNORs per cell (p < 0.0001). On multivariate survival analysis, tumor stage (p < 0.001) and AgNOR counts (p = 0.009) retained independent prognostic significance. The 16 patients with predominantly lymphocytic type and 5.75 AgNORs per cell or fewer were all alive at the end of the observation period. In conclusion, the histologic type of the American classification and the proliferative activity evaluated by AgNOR analysis are the best predictors of long-term survival for patients with thymoma. Both predictors can be easily evaluated in the same histologic section, are highly reproducible, and permit identification of a group of patients with a favorable outcome regardless of other clinicopathological features.

Adolescent↗
PubMed1995

Biological heterogeneity of diffuse mixed small and large cell non-Hodgkin's lymphomas assessed by DNA flow cytometry and Ki67.

The cell proliferative activity of the clinico-pathologically heterogeneous non-Hodgkin's lymphomas (NHL) included in the intermediate grade F category of the Working Formulation (WF) was investigated. S-phase fraction with flow cytometry on cell suspensions, and Ki67 on frozen tissue sections were performed in 42 F NHL. An avidin-biotin immunocomplex method was used and 1000 cells from 10 representative fields were counted. DNA content, S-phase and Ki67 were also detected in 194 NHL covering the whole spectrum of the WF. DNA content anomalies were found in 52 of 194 NHL. Their incidence, like that of S-phase fraction and Ki67 positive cells, progressively increased from low- to high-grade. A linear correlation was found between Ki67 and S-phase (r = .59). Using the median value of proliferating cells obtained with both procedures as a cut off, two very different groups of lymphomas could be distinguished within a series of 42 F-intermediate NHL: with low and high proliferative cell activity (p < .0001) that were termed F(low) and F(high), respectively. A intermediate group was placed between them. It differed significantly from the others if Ki67 was used but only from the F(high) group if the S-phase fraction analysis was applied. No significant differences were seen when comparing F(low) with the single categories of low-grade NHL and F(high) with H high-grade NHL; no significant differences were found between F(high) and G, and between G and H categories. The existence of distinct groups of NHL in the F category, as defined by biological parameters assessing the cell proliferative activity, indicates that this category includes biologically heterogeneous lymphoma subtypes with different grades of aggressiveness. The results also indicate that the G intermediate category displays proliferation indices similar to those of H high grade category.

Aneuploidy↗
PubMed1995

Interferon alpha treatment of relapsing-remitting multiple sclerosis: long-term study of the correlations between clinical and magnetic resonance imaging results and effects on the immune function.

Interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) are proinflammatory cytokines which may be involved in the pathogenesis of MS. IFN-alpha counteracts many of the proinflammatory actions of IFN-gamma and TNF-alpha. We treated 20 patients with relapsing-remitting (RR) MS with 9 MIU of recombinant IFN-alpha-2a (rIFN-alpha) (n = 12) or placebo (n = 8) intramuscularly every other day for 6 months. Clinical exacerbations or new or enlarging lesions at serial MRI occurred in 2/12 rIFN-alpha-treated and in 7/8 placebo-treated patients (P < 0.005). Only one new MRI lesion was detected in the rIFN-alpha group, while 27 new or enlarging lesions were detected in placebo group (P < 0.01). Baseline lymphocyte IFN-gamma (19.10 +/- 7.12 U ml-1) and TNF-alpha (18.05 +/- 5.34 pg ml-1) production significantly decreased to 3.03 +/- 0.66 (P < 0.04) (for IFN-gamma) and to 5.78 +/- 0.90 (P < 0.04) (for TNF-alpha) after rIFN-alpha treatment. IFN-gamma and TNF-alpha production was unchanged in the placebo group. rIFN-alpha was tolerated without drop-outs or serious side-effects, but fever, malaise, fatigue (interfering with daily activities in two patients) and leukopenia frequently occurred. High-dose chronic systemic rIFN-alpha might reduce clinical and MRI signs of disease activity in RRMS. The changes in cytokine production suggest that the effect is probably mediated by a down-regulation of proinflammatory cytokine.

Adolescent↗
PubMed1994

Expression of beta 1B integrin isoform in CHO cells results in a dominant negative effect on cell adhesion and motility.

The integrin subunit beta 1B, a beta 1 isoform with a unique sequence at the cytoplasmic domain, forms heterodimers with integrin alpha chains and binds fibronectin, but it does not localize to focal adhesion sites (Balzac, F., A. Belkin, V. Koteliansky, Y. Balabanow, F. Altruda, L. Silengo, and G. Tarone. 1993. J. Cell Biol. 121:171-178). Here we analyze the functional properties of human beta 1B by expressing it in hamster CHO cells. When stimulated by specific antibodies, beta 1B does not trigger tyrosine phosphorylation of a 125-kD cytosolic protein, an intracellular signalling pathway that is activated both by the endogenous hamster or the transfected human beta 1A. Moreover, expression of beta 1B results in reduced spreading on fibronectin and laminin, but not on vitronectin. Expression of beta 1B also results in severe reduction of cell motility in the Boyden chamber assay. Reduced cell spreading and motility could not be accounted for by preferential association of beta 1B with a given integrin alpha subunit. These data, together with our previous results, indicate that beta 1B interferes with beta 1A function when expressed in CHO cells resulting in a dominant negative effect on cell adhesion and migration.

Animals↗
PubMed1994

B-cell chronic lymphocytic leukaemia stage 0. An immunophenotypic study of 66 cases and comparison with B small cell lymphomas.

The cells of 66 B-CLL stage 0 patients were analyzed using a large panel of monoclonal antibodies in order to better define the immunophenotype of B-CLL. The data were compared with the immunophenotypes of lymph node cells from 51 patients with diffuse B small cell lymphoma or leukaemia with lymph node enlargement. The most frequent immunophenotype of B-CLL stage 0 was SIgM(D)+ EmR+ CD5+ CD9+ CD21+ CD23+ CD35- CD38-. Among the lymphomas, EmR-positive and EmR-negative cases were identified. The vast majority of the EmR-positive cases usually showed the leukaemic pattern, immunophenotype and lymph node histology of B-CLL. The EmR-negative cases usually had immunophenotypes quite different from those of B-CLL and the histology of indented cell lymphoma (centrocytic or intermediate) or features of lymphoplasmacytoid/cytic lymphoma. More than 20% of EmR-positive cells proved to be the most important marker to distinguish B-CLL from other lymphocytic lymphomas. Indeed this was a sign of better prognosis. Lymphoplasmacytoid/cytic lymphomas were EmR-positive with the immunophenotype of B-CLL or EmR-negative with a definitely different immunological profile. This suggests two morphologically similar but biologically different subgroups of these diseases.

Antigens, CD↗
PubMed1994

MIB-1, Ki67, and PCNA scores and DNA flow cytometry in intermediate grade malignant lymphomas.

AIMS: To verify the correlation between MIB-1, Ki67, and proliferating cell nuclear antigen (PCNA-PC10) scores and S-phase fraction in intermediate grade non-Hodgkin's lymphomas (Working Formulation F); and their reliability in differently processed tissues. METHODS: Forty one non-Hodgkin's lymphomas were classified as (F) intermediate grade malignant lymphomas according to the Working Formulation; mitotic counts and percentage of large cells were assessed for each case. Sections from formalin fixed, paraffin wax embedded tissues were stained with anti MIB-1 monoclonal antibody, after microwave oven processing, and anti-PCNA (PC10) monoclonal antibody using an avidin-biotin immunoperoxidase (ABC) method. One thousand cells from 10 representative fields were scored. Frozen sections from surgical specimens were stained with Ki67 monoclonal antibody using the ABC method; the fraction of Ki67 positive cells was calculated scoring 1000 cells. Flow cytometry analysis (FCM) was performed on cell suspensions from fresh tissues. Correlations between data were estimated using linear regression. RESULTS: A linear correlation was found between MIB-1 and Ki67 scores (r = 0.92; p < 0.00001); between MIB-1 and PCNA scores (r = 0.79; p < 0.00001); and between MIB-1 score and S-phase fraction (r = 0.51; p = 0.0006). A linear correlation was also found between Ki67 and PCNA scores (r = 0.85; p < 0.00001); between Ki67 score and S-phase fraction (r = 0.6; p = 0.0002); and between PCNA score and S-phase fraction (r = 0.74; p < 0.00001). A correlation was found between mitotic counts and MIB-1 (r = 0.56; p = 0.0001), PCNA (r = 0.51; p = 0.0007), or Ki67 scores (r = 0.47; p = 0.002); between the percentage of large cells and MIB-1 (r = 0.49; p = 0.0009), PCNA (r = 0.6; p = 0.00003), and Ki67 scores (r = 0.53; p = 0.0003) and S-phase fraction (r = 0.55; p = 0.0002). CONCLUSION: MIB-1, Ki67, and PCNA (PC10) scores and S-phase fraction are highly correlated and equally well represent the proliferative activity of intermediate grade non-Hodgkin's lymphomas in differently processed material. MIB-1 and PCNA stains can be applied even on small biopsy specimens. MIB-1 produces homogenous staining without background; it also strongly stains mitotic figures. It can be performed on routinely processed tissues, permitting the simultaneous evaluation of the morphology and tumour cell kinetics. The wide standard deviations of the proliferative indices found for intermediate grade NHL suggest that this category probably includes various degrees of malignancy.

Antibodies, Monoclonal↗
PubMed1994

Chronic systemic high-dose recombinant interferon alfa-2a reduces exacerbation rate, MRI signs of disease activity, and lymphocyte interferon gamma production in relapsing-remitting multiple sclerosis.

We report a randomized, double-blind, placebo-controlled pilot trial of systemic high-dose recombinant interferon alfa-2a (rIFNA) in 20 patients with relapsing-remitting (RR) multiple sclerosis (MS). Patients received 9 million IU rIFNA (n = 12) or placebo (n = 8) intramuscularly every other day for 6 months. Clinical exacerbations or new or enlarging lesions on serial MRI occurred in two of 12 rIFNA-treated and in seven of eight placebo-treated patients (p < 0.005). There was only one enlarging MRI lesion in the rIFNA group, whereas 27 new or enlarging lesions were present in the placebo group (p < 0.01). Baseline lymphocyte interferon gamma production of 19.10 +/- 7.12 IU/ml significantly decreased to 3.03 +/- 0.66 IU/ml (p < 0.04) in the rIFNA group, whereas production was unchanged in the placebo group. The rIFNA was tolerated without dropouts or serious side effects, but fever, malaise, fatigue (interfering with daily activities in two patients), and leukopenia occurred frequently. Neuropsychological tests excluded neurotoxicity. High-dose systemic rIFNA might reduce clinical and MRI signs of disease activity in RR MS and should be investigated in larger trials.

Adolescent↗
PubMed1993

An immunoenzyme technique for the identification of granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors using digoxigenated-GM-CSF.

A method for detecting granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors has been devised using human macrophages and a GM-CSF/IL-3-dependent human megakaryoblastic leukemia cell line (M-07e). Recognition of the factor-binding site was accomplished by linking recombinant human (rh) unglycosylated GM-CSF previously labeled with digoxigenated compounds. Digoxigenates were able to link amino and sulphydryl groups of the soluble factor and an immunoperoxidase technique using monoclonal anti-digoxigenin antibody was employed to demonstrate the interaction. To support morphological data cross-linking analysis was performed with M-07e cells using digoxigenated-rh-GM-CSF. Macrophages and M-07e cells incubated with digoxigenated-rh-GM-CSF showed intense positivity by the immunoperoxidase technique. In cross-linking, M07e cells showed a 96 kDa band corresponding to receptor plus bound factor. This technique permits a high degree of specificity in the detection of GM-CSF receptors with good morphological preservation of cellular detail.

Cells, Cultured↗
PubMed1993

Heterogeneous immunoglobulin gene rearrangement in a B-chronic lymphocytic leukemia progressing into non-Hodgkin lymphoma (Richter syndrome).

BACKGROUND: The relationship between chronic lymphocytic leukemia (CLL) and supervening non-Hodgkin lymphoma is debated, as is whether a particular genomic pattern is related to the emergence of the terminal lymphoma. To investigate these features, the molecular organization of the immunoglobulin (Ig) gene region in a case during both the B-CLL and Richter transformation phase was studied. METHODS: B-CLL and non-Hodgkin lymphoma cells were processed for Southern blot analysis of Ig heavy- and light-chain gene configuration. RESULTS: Molecular studies of B-CLL cells revealed the presence of a single Ig heavy-chain rearrangement with both kappa and lambda light-chain rearranged genes, which was consistent with the occurrence of multiple mutational events during the development of the B-CLL clone. Molecular analysis of the lymphoma DNA showed new Ig heavy- and kappa light-chain rearrangements in addition to the original ones related to the CLL phase, indicating that the lymphoma tissue consisted of two genotypically distinct populations of cells. CONCLUSIONS: On the basis of the overall molecular configuration, this heterogeneous pattern of Ig gene rearrangement was interpreted as an inherent genetic instability of the CLL clone, in which multiple mutational events allowed a selective pressure toward more aggressive subclones, resulting in the emergence of the terminal lymphoma.

Antigens, CD↗
PubMed1992

Distribution of interferon-gamma receptor in human tissues.

Interferon-gamma (IFN-gamma) is produced by activated T lymphocytes and plays a regulatory role in immune responses. The nature and location of cells that express the IFN-gamma receptor (R) and respond to this lymphokine are not well documented. The distribution of human IFN-gamma-R (HuIFN-gamma-R) was, therefore, investigated in situ by immunohistochemistry, using affinity-purified rabbit polyclonal antibodies directed against the extracellular domain of the receptor. In lymphoid organs, IFN-gamma-R expression is restricted to the B cell areas of lymph nodes, adult and fetal spleen, tonsils, appendix, and mucosa-associated lymphoid tissue of the small bowel. Macrophages and other reticular cells in lymphoid tissues and other organs are strongly positive for IFN-gamma-R, whereas its expression was consistently negative in the cortical and medullary thymocytes. Two-color flow cytofluorometric analysis of blood, lymph node, tonsil, spleen and thymus cells confirms that most B lymphocytes are IFN-gamma-R positive, whereas T lymphocytes are negative. However, after in vitro activation, peripheral blood T cells become IFN-gamma-R+. In non-lymphoid organs, IFN-gamma-R is expressed on endothelial cells of the medium- and small-size vessels. In epithelial tissues, high expression of IFN-gamma-R is detected on trophoblastic epithelium, glandular cells of stomach, ileum and colon, lung alveolar cells, salivary duct cells, renal tubular cells, and endometrial mucosa cells. Hepatocytes are weakly positive, while squamous epithelial cells are negative. The distribution of the HuIFN-gamma-R is discussed in view of the known functions of IFN-gamma.

Animals↗