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1.
J Hosp Infect ; 105(4): 615-618, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32446722

RESUMO

With the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), a high-speed and convenient detection technology should be at the forefront of medical care worldwide. This study evaluated the usefulness of GeneSoC, a compact, high-speed reciprocal flow quantitative reverse transcription polymerase chain reaction system, for the detection of SARS-CoV-2. The results support the use of this system for the rapid identification of SARS-CoV-2. This approach can contribute to the strategic selection of initial management strategies for patients with COVID-19.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/genética , Pneumonia Viral/diagnóstico , Pneumonia Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , COVID-19 , Humanos , Japão , Pandemias , SARS-CoV-2 , Sensibilidade e Especificidade
2.
Leukemia ; 18(5): 912-21, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14999295

RESUMO

Primitive hematopoietic progenitor cells such as severe combined immunodeficiency- repopulating cells and long-term culture-initiating cells are enriched in CD34+CD38- cells derived from various stem cell sources. In this study, to elucidate the features of such primitive cells at the molecular level, we tried to isolate genes that were preferentially expressed in umbilical cord blood (CB)-derived CD34+CD38- cells by subtractive hybridization. The gene for VPAC1 receptor, a receptor for the neuropeptide vasoactive intestinal peptide (VIP), was thereby isolated and it was shown that this gene was expressed in both CD34+CD38- and CD34+CD38+ CB cells and that the expression levels were higher in CD34+CD38- CB cells. Next, we assessed the effects of VIP on the proliferation of CD34+ CB cells using in vitro culture systems. In serum-free single-cell suspension culture, VIP enhanced clonal growth of CD34+ CB cells in synergy with FLT3 ligand (FL), stem cell factor (SCF), and thrombopoietin (TPO). In serum-free clonogenic assays, VIP promoted myeloid (colony-forming unit-granulocyte/macrophage (CFU-GM)) and mixed (CFU-Mix) colony formations. Furthermore, in Dexter-type long-term cultures, VIP increased colony-forming cells at week 5 of culture. These results suggest that VIP functions as a growth-promoting factor of CB-derived hematopoetic progenitor cells.


Assuntos
ADP-Ribosil Ciclase/análise , Antígenos CD34/análise , Antígenos CD/análise , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Receptores de Peptídeo Intestinal Vasoativo/análise , Peptídeo Intestinal Vasoativo/farmacologia , ADP-Ribosil Ciclase 1 , Southern Blotting , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Células-Tronco Hematopoéticas/química , Células-Tronco Hematopoéticas/fisiologia , Humanos , Glicoproteínas de Membrana , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo
3.
J Clin Endocrinol Metab ; 77(3): 704-9, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8370693

RESUMO

Interleukin-6 (IL-6) may play an important role in human CG (hCG) production by activating the IL-6-receptor (-R) system on human trophoblasts. Trophoblasts produced hCG in response to rIL-6 as well as to 8-bromo cAMP (8-Br-cAMP), 12-O-tetradecanoyl phorbol-13-acetate (TPA), and calcium ionophore A23187. To determine whether the signal transduction pathway activated by the IL-6-R system depends on protein kinases such as protein kinase A, protein kinase C, and Ca2+/calmodulin-dependent kinase, trophoblasts were stimulated with recombinant (r-) IL-6 in the presence or absence of protein kinase inhibitors such as N(2-methyl-aminoethyl)-5-isoquinoline sulfonamide dihydrochloride (H8), and 1-(5-isoquinolinesulfomyl)-2-methylpiperazine (H7) and a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1- napthalenesulfonamide (W7), H8, H7, and W7 failed to suppress rIL-6-induced hCG production but completely inhibited hCG production induced by 8-Br-cAMP, TPA, and the GnRH agonist (GnRHa), respectively. In contrast, genistein, a tyrosine kinase inhibitor, completely suppressed rIL-6-induced hCG production but failed to inhibit hCG production induced by 8-Br-cAMP, TPA, and A23187. Genistein also did not suppress GnRH-induced hCG production. The addition of genistein to rIL-1- and rTNF-alpha-stimulated trophoblasts inhibited rIL-1-induced and rTNF-alpha induced hCG production but maintained rIL-1- and rTNF-alpha-induced IL-6 production. These results show that the IL-6/IL-6-R system-induced signal transduction pathway in the placenta probably stimulates hCG production by activating a tyrosine kinase pathway. The experiment with genistein shows that the GnRH/GnRH-R system activates a signal transduction pathway distinct from that activated by the IL-6/IL-6-R system.


Assuntos
Gonadotropina Coriônica/biossíntese , Hormônio Liberador de Gonadotropina/farmacologia , Interleucina-6/fisiologia , Proteínas Tirosina Quinases/metabolismo , Receptores Imunológicos/fisiologia , Transdução de Sinais/fisiologia , Trofoblastos/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Calcimicina/farmacologia , Calmodulina/antagonistas & inibidores , Ativação Enzimática , Feminino , Genisteína , Humanos , Interleucina-1/farmacologia , Interleucina-6/biossíntese , Interleucina-6/farmacologia , Isoflavonas/farmacologia , Inibidores de Proteínas Quinases , Receptores de Interleucina-6 , Proteínas Recombinantes/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Trofoblastos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
4.
J Clin Endocrinol Metab ; 72(3): 594-601, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1997513

RESUMO

Interleukin-1 (IL-1) has a unique activity to stimulate the release of multiple hormones in a number of human and murine endocrine systems. IL-6 also expresses such activities by activating IL-6-receptor (R)-mediated signal transduction pathways. Since the placenta produces both of these cytokines and endocrine hormones such as hCG, we investigated how these cytokines regulate hCG release by normal trophoblasts. Trophoblasts purified by Percoll density gradient released hCG from 120 min after stimulation with recombinant (r) IL-1 alpha, and its release was dependent on the rIL-1 alpha concentration used. The rIL-1 alpha-stimulated trophoblasts released a molecule with IL-6 activity antecedently, as determined by an IL-6-dependent cell line, MH60.BSF2 cells. The IL-6 identity of the released molecule was confirmed by goat anti-IL-6 antiserum. rIL-1-mediated hCG release from trophoblasts was completely abrogated to the basal level by pretreatment of the trophoblasts with PM1, an anti-IL-6-R monoclonal antibody. Identical results were observed with rIL-1 beta. These results showed that rIL-1-induced hCG release was totally dependent on IL-6- and IL-6-R-mediated signal transduction in human trophoblasts. The presence of peripheral monocytes in the purified trophoblast fraction, however, induced a rapid decrease in IL-6 and hCG release after their maximal release, suggesting some regulatory interaction between trophoblasts and the monocytes. In contrast, rIL-1-mediated enhancement of IL-6 and hCG secretion by purified trophoblasts was no longer observed at 24 h compared with that of the unstimulated trophoblasts, while spontaneous hCG secretion was significantly inhibited by pretreatment of trophoblasts with PM1. The results showed that IL-6 and hCG secretion might also be regulated by a number of agents besides IL-1, and that hCG secretion as well as its release is dependent on IL-6 and IL-6-R system in trophoblasts.


Assuntos
Gonadotropina Coriônica/metabolismo , Interleucina-1/farmacologia , Interleucina-6/farmacologia , Receptores Imunológicos/farmacologia , Trofoblastos/efeitos dos fármacos , Anticorpos/imunologia , Ligação Competitiva , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Receptores Imunológicos/imunologia , Receptores de Interleucina-6 , Fatores de Tempo
5.
J Clin Endocrinol Metab ; 71(2): 436-41, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2116439

RESUMO

We examined the capacity of trophoblast-derived interleukin-6 (IL-6) to stimulate secretion of placental hormones, including hCG. IL-6 stimulated hCG secretion by trophoblasts to a level similar to that stimulated by a GnRH analog. The analog, however, released hCG by an IL-6-independent mechanism because PM-1, a monoclonal antibody specific for IL-6 receptors (R), failed to block GnRH-mediated responses, but completely blocked IL-6-mediated hCG secretion, suggesting the existence of two distinct regulatory pathways for hCG release. Immunohistochemical analysis with another IL-6-R-specific antibody, MT-18, showed that IL-6-R was located only on the trophoblast layer of the placenta. Our data revealed the existence of a local regulatory network by which trophoblast-derived IL-6 interacts with IL-6-R on the trophoblasts, resulting in hCG release. Thus, two different regulatory networks, an IL-6 and IL-6-R system and a GnRH and GnRH-R system, regulate hCG release by human trophoblasts independently.


Assuntos
Gonadotropina Coriônica/metabolismo , Interleucina-6/farmacologia , Trofoblastos/metabolismo , Anticorpos Monoclonais , Células Cultivadas , Escherichia coli/genética , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Hormônios/farmacologia , Humanos , Cinética , Leuprolida , Placenta/metabolismo , Gravidez , Proteínas Recombinantes/farmacologia , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos
6.
J Clin Endocrinol Metab ; 74(6): 1389-95, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1317386

RESUMO

The status of preservation of the ability to secrete cytokines, such as interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and IL-6, and the cytokine-mediated regulatory cascade was investigated in four choriocarcinoma cell lines. Each cell line constitutively produced IL-6, but not IL-1 alpha, IL-1 beta, or TNF alpha. Jar and HCCM-5 cells responded to IL-6, releasing hCG by direct activation of IL-6 receptors (IL-6-R) with IL-6. Both cell lines also responded to IL-1, but failed to responded to TNF alpha. When stimulated with recombinant IL-1 alpha, both cell lines released IL-6 and activated the IL-6-R system to release hCG, whereas stimulation with TNF alpha failed to release hCG. The experiments showed that both the Jar and HCCM-5 cell lines possessed a partially intact cytokine-mediated cascade, suggesting that IL-1-induced IL-6 release and IL-6-R activation operate in an autocrine manner. In contrast, NUC-1 and SCH cells failed to respond to IL-6, IL-1, or TNF alpha. Although 8-bromo-cAMP, which is a cAMP analog, stimulates hCG release by Jar cells, it failed to stimulate IL-6 release. Moreover, cAMP-mediated hCG release was not blocked by PM1, an anti-IL-6-R antibody. This suggests that elevation of the cytoplasmic cAMP level might activate a pathway different from the IL-6- and IL-6-R-dependent pathway. Moreover, IL-1- and IL-6-mediated hCG release was not blocked by H8, a cAMP-dependent kinase inhibitor, which further suggests that the IL-1- and IL-6-mediated pathway functions independently of the cAMP-dependent pathway in releasing hCG in Jar cells.


Assuntos
8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Gonadotropina Coriônica/metabolismo , AMP Cíclico/farmacologia , Interleucina-1/farmacologia , Interleucina-6/farmacologia , Receptores Imunológicos/fisiologia , Transdução de Sinais/fisiologia , Linhagem Celular , Coriocarcinoma , AMP Cíclico/metabolismo , Feminino , Humanos , Interleucina-1/metabolismo , Interleucina-6/biossíntese , Interleucina-6/fisiologia , Isoquinolinas/farmacologia , Cinética , Gravidez , Inibidores de Proteínas Quinases , Receptores Imunológicos/efeitos dos fármacos , Receptores de Interleucina-6 , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Neoplasias Uterinas
7.
J Clin Endocrinol Metab ; 74(1): 184-91, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1727819

RESUMO

The titer of tumor necrosis factor-alpha (TNF alpha) secreted by placental blocks was determined by enzyme immunoassay. The source of placental TNF alpha was immunohistochemically demonstrated with monoclonal anti-TNF alpha antibody to be only trophoblasts. Purified trophoblasts produced 174.4 ng/L TNF alpha by 24 h of culture in vitro. To investigate the role of TNF alpha in placental hormonogenesis, purified trophoblasts were stimulated with recombinant TNF alpha (rTNF alpha) to determine the hCG titer by enzyme immunoassay. Trophoblasts stimulated with rTNF alpha released hCG in a dose-dependent fashion with kinetics similar to those of recombinant interleukin-1 (rIL-1)-stimulated trophoblasts. The stimulated trophoblasts released IL-6 before hCG, but failed to show hCG release when pretreated with anti-IL-6 receptor (anti-IL-6-R) monoclonal antibody PM-1. However, the pretreatment of trophoblasts with PM-1 did not interfere with rTNF alpha-induced IL-6 release, ruling out the possibility of a nonspecific toxic effect of PM-1 on trophoblasts. These results suggest that trophoblast-derived TNF alpha induced IL-6 release and then activated the IL-6-R system in trophoblasts to release hCG. Since IL-1 has also been demonstrated to induce similar release of IL-6 and hCG from trophoblasts, the effects of TNF alpha and IL-1 on these trophoblast functions were also examined. Simultaneous stimulation of trophoblasts with rTNF alpha and gamma IL-1 alpha resulted in synergistic enhancement of IL-6 release, subsequently leading to enhanced hCG release. Collectively, trophoblast-derived TNF alpha and IL-1 synergistically regulated the level of IL-6 secreted by trophoblasts, the magnitude of which determined the level of hCG released by activating the IL-6-R system in trophoblasts.


Assuntos
Gonadotropina Coriônica/metabolismo , Interleucina-6/farmacologia , Receptores Imunológicos/fisiologia , Trofoblastos/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Anticorpos Monoclonais/imunologia , Gonadotropina Coriônica/antagonistas & inibidores , Sinergismo Farmacológico , Humanos , Interleucina-1/farmacologia , Receptores Imunológicos/imunologia , Receptores de Interleucina-6 , Proteínas Recombinantes , Valores de Referência , Trofoblastos/química , Fator de Necrose Tumoral alfa/análise
8.
J Clin Endocrinol Metab ; 74(1): 211-6, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1727823

RESUMO

Using a transforming growth factor-beta (TGF beta)-sensitive cell line, Mv1Lu (or CCL 64), we demonstrated that trophoblasts predominantly produced a latent form of TGF beta. After converting latent TGF beta to active TGF beta in vitro by acid (pH 2.5), alkali (pH 10.0), or heat (90 C; 10 min) treatment, addition of rabbit anti-TGF beta 1 antiserum resulted in the elimination of TGF beta activity, thus suggesting that trophoblasts produced at least a certain amount of latent TGF beta 1. To investigate the role of TGF beta 1 in placental hormonogenesis, we first studied the effect of recombinant (r) TGF beta 1 on the production of interleukin-6 (IL-6) and hCG by trophoblasts. rTGF beta 1 exerted no inhibitory activity on IL-6 and hCG production. The effect of rTGF beta 1 on cytokine-induced IL-6 and hCG release was then examined. While rTGF beta 1 failed to inhibit basal hCG secretion, it did inhibit recombinant tumor necrosis factor-alpha (rTNF alpha)-induced IL-6 release as well as rTNF alpha- and rIL-6-induced hCG release in a dose-dependent manner. However, rIL-1 alpha-induced IL-6 and hCG release was remarkably sensitive to rTGF beta 1-mediated suppression. In contrast, GnRH-induced hCG release, the response of which is independent of the IL-6 and IL-6 receptor system in trophoblasts, was completely resistant to rTGF beta 1. Thus, trophoblast-derived TGF beta 1 is an important regulatory molecule of cytokine-dependent, but not cytokine-independent, hCG release, possibly by converting latent TGF beta to active TGF beta at the local site of trophoblasts.


Assuntos
Gonadotropina Coriônica/metabolismo , Citocinas/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Trofoblastos/metabolismo , Humanos , Interleucina-1/antagonistas & inibidores , Interleucina-6/metabolismo , Proteínas Recombinantes , Valores de Referência , Fator de Crescimento Transformador beta/análise , Trofoblastos/química
9.
J Clin Endocrinol Metab ; 80(10): 2912-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7559874

RESUMO

To study the role of soluble interleukin-6 receptor (sIL-6R) during pregnancy, sIL-6R levels in the sera of pregnant women in the first, second, and third trimesters were determined and found to remain unchanged during pregnancy, but were significantly higher than those in nonpregnant women in the follicular, ovulatory, and luteal phases of the menstrual cycle (P < 0.001). IL-6 levels, however, in the sera of pregnant women at all trimesters showed no difference from those in nonpregnant women at any stage of the menstrual cycle. Recombinant sIL-6R (rsIL-6R) augmented hCG production by rIL-6-stimulated trophoblasts dose dependently, but failed to enhance hCG production by unstimulated trophoblasts. rIL-6- and rsIL-6R-induced hCG production was significantly blocked by anti-IL-6R antibody, PM1; antisignal transducing glycoprotein 130 (gp130) antibody, GPX7; or a tyrosine kinase inhibitor, genistein. Thus, sIL-6R in serum from pregnant women forms a complex with placental and decidual IL-6 in a manner similar to trophoblast membrane-bound IL-6R. These two discrete types of IL-6R and IL-6 complex might act cooperatively by binding to gp130 and subsequently evoking tyrosine kinase activity in the trophoblasts to produce hCG in vivo.


Assuntos
Antígenos CD/análise , Antígenos CD/metabolismo , Gonadotropina Coriônica/biossíntese , Interleucina-6/metabolismo , Ciclo Menstrual/imunologia , Gravidez/sangue , Gravidez/imunologia , Receptores de Interleucina/análise , Receptores de Interleucina/metabolismo , Trofoblastos/metabolismo , Aborto Legal , Biomarcadores/sangue , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Interleucina-6/farmacologia , Ciclo Menstrual/sangue , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Receptores de Interleucina-6 , Trofoblastos/efeitos dos fármacos , Trofoblastos/imunologia
10.
J Clin Endocrinol Metab ; 80(4): 1449-56, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7714123

RESUMO

We investigated the role of leukemia inhibitory factor (LIF) at the implantation site of human embryos. The first trimester decidual tissue produced higher levels of LIF than chorionic tissue, but the decidua produced much smaller amounts of interleukin-6 (IL-6) than the chorion in vitro, as determined by enzyme-linked immunosorbent assay. The reverse transcription-polymerase chain reaction and immunohistochemical analysis revealed the expression and localization, on the trophoblasts, of glycoprotein 130 (gp130), an IL-6 signal transducer receptor component shared by the cytokines such as LIF and IL-6. Trophoblasts stimulated by recombinant LIF (rLIF) produced CG titer at the amount similar to that induced by rIL-6. Recombinant LIF-induced CG production was significantly blocked by anti-gp130 antibody but not by anti-IL-6 receptor antibody, whereas rIL-6-induced CG was completely blocked by both antibodies. Recombinant LIF- and rIL-6-induced CG productions were both significantly blocked by genistein, a tyrosine kinase inhibitor, suggesting an involvement of tyrosine kinase in gp130-mediated CG production. Since CG is capable of stimulating trophoblast growth and differentiation as well as placental metabolism, LIF produced at the fetomaternal interface are considered to stimulate the trophoblasts to produce CG, which may contribute to the maintenance of the placental functions and embryonal growth.


Assuntos
Antígenos CD , Gonadotropina Coriônica/biossíntese , Implantação do Embrião/fisiologia , Inibidores do Crescimento/fisiologia , Interleucina-6 , Linfocinas/fisiologia , Gravidez/fisiologia , Anticorpos/imunologia , Vilosidades Coriônicas/metabolismo , Receptor gp130 de Citocina , Decídua/metabolismo , Feminino , Genisteína , Inibidores do Crescimento/farmacologia , Humanos , Isoflavonas/farmacologia , Fator Inibidor de Leucemia , Linfocinas/farmacologia , Glicoproteínas de Membrana/metabolismo , Placenta/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Recombinantes
11.
J Endocrinol ; 155(3): 401-10, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9487985

RESUMO

Chorioamnionitis has been shown to be one of the most important factors in inducing preterm delivery. The present study was undertaken to examine the effects of chorioamnionitis on placental endocrine functions. Preterm placentas with histologic chorioamnionitis produced smaller amounts of human chorionic gonadotropin (hCG) and human placental lactogen (hPL) than those without chorioamnionitis (P < 0.001). To examine the mechanism involved in the suppression of placental endocrine functions induced by chorioamnionitis, we initially confirmed the expression of lipopolysaccharide (LPS) receptor, i.e. the CD14 molecule, on trophoblasts by Northern blot analysis and immunohistochemistry. We then stimulated purified trophoblasts with LPS, which is the major agent which induces inflammatory responses in the host via the LPS receptor. The trophoblasts stimulated with LPS produced reduced amounts of hCG, hPL, and progesterone in a time- and dose-dependent fashion in spite of the induced manganese-superoxide dismutase (SOD) synthesis. Stimulation of trophoblasts with hypoxanthine and xanthine oxidase resulted in suppressed hCG production, while the simultaneous addition of SOD into the culture medium reversed the suppression of hCG production. LPS in the placenta with chorioamnionitis might directly stimulate trophoblasts through the LPS receptor (CD14), thus reducing placental endocrine functions. Superoxide anions which exogenously act on trophoblasts might be generated by simultaneous stimulation of neutrophils and monocytes at the feto-maternal interface by LPS, and additively reduce placental endocrine functions.


Assuntos
Corioamnionite/metabolismo , Gonadotropina Coriônica/biossíntese , Trabalho de Parto Prematuro/metabolismo , Placenta/metabolismo , Lactogênio Placentário/biossíntese , Adulto , Northern Blotting , Células Cultivadas , Feminino , Humanos , Hipoxantinas/farmacologia , Imuno-Histoquímica , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Placenta/efeitos dos fármacos , Placenta/imunologia , Gravidez , Progesterona/biossíntese , Estimulação Química , Superóxido Dismutase/farmacologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/imunologia , Trofoblastos/metabolismo , Xantina Oxidase/farmacologia
12.
Placenta ; 15(5): 453-66, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7997446

RESUMO

Human immunoglobulin G (IgG) Fc receptors are important in the materno-fetal relationship. Three classes of IgG Fc receptors are recognized which generate multiple isoforms, most of which are expressed in different cellular components of human placenta at different times during pregnancy. Although the distinct biological functions of Fc gamma R phenotypes expressed in human placenta are still unknown, recent data provide evidence for an important association between the Fc gamma R phenotype and transcytosis of IgG in the placenta. Selective transfer of maternal IgG across the placenta provides passive immunity to the fetus during the period when its own immune system is gaining protective potential. Furthermore, placenta-specific macrophages may contribute through Fc gamma R-mediated phagocytosis to the protection of the fetus from either infection or maternal immune attack against paternally inherited fetal antigens. Ontogeny and expression of various isoforms of Fc gamma R subtypes may be the key to the elucidation of the transport mechanism of maternal IgG to the fetus, in addition to the determination of the mechanisms of placental protection of the fetus against the maternal immune system.


Assuntos
Imunidade Materno-Adquirida , Placenta/imunologia , Receptores Fc/metabolismo , Feminino , Humanos , Macrófagos/imunologia , Gravidez , Receptores Fc/imunologia
13.
Placenta ; 12(1): 15-26, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1827890

RESUMO

We investigated the localization of the three subtypes of (Fc gamma R) in the normal human placenta using immunohistochemical and immunocytochemical techniques with specific monoclonal antibodies. The analysis revealed that Fc gamma RI was expressed on Hofbauer cells, that Fc gamma RII was expressed on Hofbauer cells and endothelial cells of fetal vessels, while Fc gamma RIII was expressed on trophoblasts, especially syncytiotrophoblasts. Moreover, we demonstrated that the expression of Fc gamma RI and Fc gamma RII on Hofbauer cells and endothelial cells of the fetal vessels in the 1st trimester placenta was different from that in the 3rd trimester placenta. These results, therefore, indicate that the three subtypes of Fc gamma R in the human placenta may contribute to maintenance of placental functions, because each Fc gamma R molecule displays unique biological functions similar to those on leukocytes.


Assuntos
Antígenos de Diferenciação/análise , Placenta/citologia , Placenta/imunologia , Receptores Fc/análise , Animais , Anticorpos Monoclonais , Antígenos de Diferenciação/classificação , Feminino , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G , Imuno-Histoquímica , Camundongos , Gravidez , Receptores Fc/classificação , Receptores de IgG , Tripsina
14.
Placenta ; 11(3): 205-13, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2371251

RESUMO

The placenta plays a number of important roles during pregnancy, some of which might be mediated by cytokines with multiple activities such as IL-6. Using an IL-6-dependent cell line, MH6o.BSF2, we showed that the placenta released IL-6 into the culture supernatant. Analysis of single-cell suspensions of placental cells determined the major source of IL-6 to be trophoblast. Using a mouse monoclonal antibody specific for IL-6 (alpha BSF2-I66), immuno-histochemical analysis of placental specimens demonstrated the localization of IL-6 only in the trophoblast layer. Additional immunocytochemical studies with single-cell suspensions of trophoblasts demonstrated the preferential presence of IL-6 molecules in syncytiotrophoblasts rather than cytotrophoblasts. The evidence that a high titer of IL-6 is produced spontaneously by syncytiotrophoblasts indicates that IL-6 may play immunological roles in fetomaternal interactions by means of IL-6-driven multiple immunoregulatory activities.


Assuntos
Interleucina-6/biossíntese , Trofoblastos/metabolismo , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Placenta/metabolismo , Gravidez
15.
J Reprod Immunol ; 15(3): 181-94, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2503614

RESUMO

We have investigated the functional ability of a choriocarcinoma-cell-derived factor to block human T cell responses and the factor's immunoregulatory site of action on the T cell signal transduction pathway. The factor completely suppressed human T cell responses activated by phorbol ester and calcium ionophore, reagents which strongly stimulate IL-2-mediated T cell responses. It failed to inhibit CD 25 expression and IL-2 production by T cell blasts in the T cell activation phase, but completely blocked recombinant IL-2-induced proliferation of T cell blasts in the T cell proliferation phase. Absorption experiments with the factor and Con A-induced T cell blasts as well as [125I]IL-2 binding experiments with T cell blasts revealed that the factor acted on the physiological events occurring after IL-2-mediated stimulation of IL-2 receptor complexes, demonstrating no interaction of the factor with either IL-2 molecules or IL-2 receptor complexes. Moreover, it suppressed murine IL-2 dependent T cell line proliferation, suggesting the presence of common pathways in human and murine T cell proliferation. The biological and immunological significance of the factor during pregnancy and in the immunosuppressed tumor-bearing hosts are discussed.


Assuntos
Tolerância Imunológica , Fatores Supressores Imunológicos/farmacologia , Linfócitos T/fisiologia , Trofoblastos/imunologia , Calcimicina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Coriocarcinoma , Concanavalina A/farmacologia , Humanos , Interleucina-2/farmacologia , Interleucina-2/fisiologia , Receptores de Interleucina-2/fisiologia , Proteínas Recombinantes/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas
16.
J Reprod Immunol ; 23(1): 1-12, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8429521

RESUMO

IL-8 is a chemotactic and activating cytokine for neutrophils which eliminate invading bacteria by releasing bactericidal metabolites. Cord blood mononuclear cells (CBMCs) obtained from neonates born to mothers with chorioamnionitis actively produced a significantly higher amount of IL-8 than those of neonates without chorioamnionitis, suggesting that the mononuclear cells of fetuses with chorioamnionitis had been activated in utero. As lipopolysaccharide (LPS) can often be detected in the uteroplacental space in chorioamnionitis, the LPS-mediated activation mechanism of neonatal mononuclear cells was analyzed in vitro to produce IL-8. Neonatal mononuclear cells stimulated with LPS increased IL-8 production in a time- and dose-dependent manner. The ability of term or preterm neonatal mononuclear cells to produce IL-8 was comparable with that of adult (maternal) mononuclear cells, suggesting functional maturity of the neonatal or fetal mononuclear cells to produce IL-8. However, IL-8 production by neonatal CBMCs was down-regulated by dexamethasone, a glucocorticoid which is clinically administered to mothers to promote fetal lung maturity in preterm delivery. Our present study revealed a regulatory mechanism of fetal IL-8 production, suggesting that functionally mature fetal mononuclear cells produce IL-8 in response to LPS in chorioamnionitis and activate the fetal defense mechanism against infection.


Assuntos
Corioamnionite/imunologia , Sangue Fetal/citologia , Interleucina-8/biossíntese , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/farmacologia , Gravidez/sangue , Células Cultivadas , Dexametasona/farmacologia , Relação Dose-Resposta Imunológica , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Recém-Nascido , Leucócitos Mononucleares/efeitos dos fármacos , Fatores de Tempo
17.
J Reprod Immunol ; 19(2): 101-14, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2008000

RESUMO

The immunosuppressive activity of a JEG-3 choriocarcinoma-derived factor in human IL-2-dependent T cell responses has been studied, together with its effect on IL-2-independent T cell responses induced by 10 nM TPA. The factor completely suppressed the IL-2-independent proliferative responses of T cells but failed to suppress antigenic expression of activation-associated CD 25 molecules. Further studies examined the effect of the factor on LAK cell generation induced by rIL-2. Recombinant IL-2-induced LAK cell proliferation was observed on Day 4 and Day 5, but not on Day 3. As the factor suppressed the responses of LAK cell proliferation, we tested whether it blocked the generation of Day 3, Day 4 and Day 5 LAK cells. The addition of the factor failed to suppress the generation of Day 3 LAK cells, while it partially suppressed the lytic activity of Day 4 LAK cells and completely suppressed that of Day 5 LAK cells. The data suggest the presence of a heterogeneous pattern for LAK cell generation; one without proliferation, but the other requiring proliferation, to acquire killer activity. Taken together with the evidence that the factor failed to suppress NK activity, the choriocarcinoma-derived factor suppressed only the proliferative events of immunocompetent cells, but inhibited neither their activation nor the differentiation events. This immunosuppressive factor might be involved in the prevention of host-mediated rejection of choriocarcinoma cells or maternal rejection of the fetus.


Assuntos
Coriocarcinoma/imunologia , Fatores Supressores Imunológicos/isolamento & purificação , Neoplasias Uterinas/imunologia , Feminino , Humanos , Tolerância Imunológica , Imunidade Celular , Interleucina-2/farmacologia , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Gravidez , Fatores Supressores Imunológicos/farmacologia , Linfócitos T/imunologia , Células Tumorais Cultivadas/imunologia
18.
Obstet Gynecol ; 82(4 Pt 1): 494-9, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8377970

RESUMO

OBJECTIVE: To determine the relationships among the pregnancy outcomes of growth-retarded fetuses, Doppler flow velocimetry of the fetomaternal circulation, and pathologic changes in the placenta. METHODS: Forty-seven fetuses confirmed to be growth-retarded by ultrasonographic biometry were monitored during pregnancy in terms of the resistance indexes of the maternal uterine, fetal umbilical, and fetal middle cerebral arteries. After delivery, the placentas were examined for pathologic changes such as infarction and villous ischemia. RESULTS: Compared with 23 fetuses with nonischemic placentas, 24 growth-retarded fetuses whose placentas showed ischemic lesions were more frequently delivered preterm (P < .001) and by cesarean for fetal distress (P < .01), and they also had lower mean pH, higher carbon dioxide pressure, and lower oxygen pressure values (P < .05). Compared with the fetal umbilical and middle cerebral artery resistance indexes, the uterine artery resistance index showed the highest sensitivity (91.7%), specificity (78.3%), and positive predictive value (81.5%) for detecting placental ischemic changes. Linear discriminative analysis also showed that the uterine artery resistance index had the strongest correlation (P < .00001) with the placental ischemic changes. CONCLUSION: Ischemia of the placenta is associated with an adverse pregnancy outcome in growth-retarded fetuses. The placental ischemic changes can be detected using Doppler flow velocimetry. Measurement of the uterine artery resistance index might be useful for determining the clinical management of growth-retarded fetuses.


Assuntos
Retardo do Crescimento Fetal/diagnóstico por imagem , Isquemia/diagnóstico , Placenta/irrigação sanguínea , Ultrassonografia Pré-Natal , Útero/irrigação sanguínea , Adulto , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Velocidade do Fluxo Sanguíneo , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiopatologia , Análise Discriminante , Feminino , Humanos , Placenta/patologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Sensibilidade e Especificidade , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/fisiopatologia , Resistência Vascular
19.
Obstet Gynecol ; 85(2): 242-9, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7824239

RESUMO

OBJECTIVE: To examine endocrine states of mothers with normal 75-g oral glucose tolerance tests (GTTs) who gave birth to large for gestational age (LGA) neonates (group I) and to examine those neonates. METHODS: We examined plasma glucose levels and serum immunoreactive insulin responses after the 75-g oral GTT was given to group I mothers (N = 34), mothers with an abnormal oral GTT who gave birth to LGA neonates (group II, N = 21), and those with normal oral GTTs having appropriate for gestational age neonates (group III, N = 173). We also examined the infants, checking neonatal birth weight, levels of immunoreactive insulin and C-peptide immunoreactivity in cord sera at birth and the lowest blood sugar level after birth to see if a correlation existed between them. RESULTS: Group I and II mothers showed higher titers in plasma glucose levels and remarkably enhanced ratios of 60- to 30-minute immunoreactive insulin values (immunoreactive insulin up-ratio) after load compared with those of group III mothers. Cord serum immunoreactive insulin and C-peptide immunoreactivity were significantly higher and the lowest blood sugar level was significantly reduced in group I and II neonates compared with those in group III. We observed a positive correlation between cord serum immunoreactive insulin, C-peptide immunoreactivity, and birth weight, but a negative correlation between cord serum immunoreactive insulin, birth weight, and the lowest blood sugar level in group I and II neonates (strongest tendency in group II), but not in group III neonates. CONCLUSION: All of the abnormal carbohydrate metabolic responses in group I mothers and neonates may result in the promotion of growth in LGA fetuses similar to group II, but to a lesser extent. Identification of group I mothers by the immunoreactive insulin up-ratio after oral GTT will help predict the occurrence of LGA neonates and their possible hypoglycemia.


Assuntos
Peso ao Nascer , Teste de Tolerância a Glucose , Glicemia/análise , Peptídeo C/sangue , Feminino , Sangue Fetal/química , Intolerância à Glucose/complicações , Humanos , Recém-Nascido , Insulina/sangue , Insulina/imunologia , Gravidez , Complicações na Gravidez
20.
Fertil Steril ; 59(4): 885-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8458511

RESUMO

OBJECTIVE: To determine if interleukin-8 (IL-8) is a normal constituent of seminal plasma and if leukospermia is a factor determining its elevation. DESIGN: Seminal plasma from 58 men obtained by masturbation was examined for the presence of IL-8 using an IL-8 specific sandwich ELISA. Semen samples were obtained from 34 infertile men without leukospermia, 10 infertile men with leukospermia, and 14 proven fertile men. The correlation of amount of IL-8 in seminal plasma with some spermiogram parameters and the amount of polymorphonuclear (PMN) elastase was statistically evaluated. RESULTS: Immunoreactive IL-8 was observed in the seminal plasma of all 58 subjects. The IL-8 titer in seminal plasma of patients with leukospermia (6.16 +/- 0.82 micrograms/L) was significantly higher than that in seminal plasma of patients without leukospermia (2.35 +/- 0.34 micrograms/L) and fertile men (1.64 +/- 0.29 micrograms/L). There was a high degree of correlation between PMN elastase and IL-8 levels in seminal plasma. CONCLUSIONS: These findings demonstrate IL-8 to be in seminal plasma and elevated IL-8 levels in infertile patients with leukospermia.


Assuntos
Infertilidade Masculina/metabolismo , Interleucina-8/sangue , Leucócitos , Sêmen/química , Humanos , Interleucina-8/biossíntese , Elastase de Leucócito , Masculino , Elastase Pancreática/sangue , Sêmen/citologia , Sêmen/enzimologia
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