Spontaneous Abortion and Chikungunya Infection: Pathological Findings

Intrauterine transmission of the Chikungunya virus (CHIKV) during early pregnancy has rarely been reported, although vertical transmission has been observed in newborns. Here, we report four cases of spontaneous abortion in women who became infected with CHIKV between the 11th and 17th weeks of pregnancy. Laboratorial confirmation of the infection was conducted by RT-PCR on a urine sample for one case, and the other three were by detection of IgM anti-CHIKV antibodies. Hematoxylin and eosin (H&E) staining and an electron microscopy assay allowed us to find histopathological, such as inflammatory infiltrate in the decidua and chorionic villi, as well as areas of calcification, edema and the deposition of fibrinoid material, and ultrastructural changes, such as mitochondria with fewer cristae and ruptured membranes, endoplasmic reticulum with dilated cisterns, dispersed chromatin in the nuclei and the presence of an apoptotic body in case 1. In addition, by immunohistochemistry (IHC), we found a positivity for the anti-CHIKV antibody in cells of the endometrial glands, decidual cells, syncytiotrophoblasts, cytotrophoblasts, Hofbauer cells and decidual macrophages. Electron microscopy also helped in identifying virus-like particles in the aborted material with a diameter of 40–50 nm, which was consistent with the size of CHIKV particles in the literature. Our findings in this study suggest early maternal fetal transmission, adding more evidence on the role of CHIKV in fetal death.

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The Role of Microscopy in Preclinical Safety Assessment

Microscopy and Microanalysis ◽

10.1017/s143192760003748x ◽

2000 ◽

Vol 6 (S2) ◽

pp. 998-999

Author(s):

Barbara J. Dovey-Hartman

Keyword(s):

Electron Microscopy ◽

Vital Role ◽

Pathology Report ◽

Clinical Phase ◽

Transmission Electron ◽

New Chemical Entities ◽

Regulatory Submissions ◽

Hematoxylin And Eosin ◽

Preclinical Safety

Microscopy plays a vital role in assessing the safety of New Chemical Entities (NCE) in the pre-clinical phase of drug development. Light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) are used at the Schering-Plough Research Institute (SPRI) for evaluation of NCE. To support regulatory submissions, NCE are routinely tested in rodents in short-term studies such as one-month toxicity studies, and in longterm studies such as oncogenicity studies that may last 24 months. At the completion of a study, the animals are necropsied and the required tissues collected and stored in fixative. The tissues for LM are processed to slides and stained with Hematoxylin and Eosin (H&E). The information derived from the examination of these tissues by LM becomes an essential part of the pathology report. The LM examination of these tissues usually yields the information needed to either progress a NCE or otherwise deter or halt development.

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Recent Updates on Research Models and Tools to Study Virus–Host Interactions at the Placenta

Viruses ◽

10.3390/v12010005 ◽

2019 ◽

Vol 12 (1) ◽

pp. 5 ◽

Cited By ~ 5

Author(s):

Jae Kyung Lee ◽

Soo-Jin Oh ◽

Hosun Park ◽

Ok Sarah Shin

Keyword(s):

Viral Infections ◽

Protective Role ◽

Biological Mechanisms ◽

Cellular Targets ◽

Host Interactions ◽

Wide Range ◽

Hofbauer Cells ◽

Maternal Fetal Transmission ◽

Immunological Barrier

The placenta is a unique mixed organ, composed of both maternal and fetal tissues, that is formed only during pregnancy and serves as the key physiological and immunological barrier preventing maternal–fetal transmission of pathogens. Several viruses can circumvent this physical barrier and enter the fetal compartment, resulting in miscarriage, preterm birth, and birth defects, including microcephaly. The mechanisms underlying viral strategies to evade the protective role of placenta are poorly understood. Here, we reviewed the role of trophoblasts and Hofbauer cells in the placenta and have highlighted characteristics of vertical and perinatal infections caused by a wide range of viruses. Moreover, we explored current progress and future opportunities in cellular targets, pathogenesis, and underlying biological mechanisms of congenital viral infections, as well as novel research models and tools to study the placenta.

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The Elusive Role of Placental Macrophages: The Hofbauer Cell

Journal of Innate Immunity ◽

10.1159/000497416 ◽

2019 ◽

Vol 11 (6) ◽

pp. 447-456 ◽

Cited By ~ 10

Author(s):

Michael Z. Zulu ◽

Fernando O. Martinez ◽

Siamon Gordon ◽

Clive M. Gray

Keyword(s):

Human Placenta ◽

Viral Infections ◽

Normal Pregnancy ◽

Adverse Birth Outcomes ◽

Regulatory Cells ◽

Chorionic Villi ◽

Immunodeficiency Virus ◽

Hofbauer Cells ◽

Placental Macrophages

In this review, we discuss the often overlooked tissue-resident fetal macrophages, Hofbauer cells, which are found within the chorionic villi of the human placenta. Hofbauer cells have been shown to have a phenotype associated with regulatory and anti-inflammatory functions. They are thought to play a crucial role in the regulation of pregnancy and in the maintenance of a homeostatic environment that is crucial for fetal development. Even though the numbers of these macrophages are some of the most abundant immune cells in the human placenta, which are sustained throughout pregnancy, there are very few studies that have identified their origin, their phenotype, and functions and why they are maintained throughout gestation. It is not yet understood how Hofbauer cells may change in function throughout normal pregnancy, and especially in those complicated by maternal gestational diabetes, preeclampsia, and viral infections, such as Zika, cytomegalovirus, and human immunodeficiency virus. We review what is known about the origin of these macrophages and explore how common complications of pregnancy dysregulate these cells leading to adverse birth outcomes in humans. Our synthesis sheds light on areas for human studies that can further define these innate regulatory cells.

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TLR2 deficiency promotes IgE and inhibits IgG1 class-switching following ovalbumin sensitization

Italian Journal of Pediatrics ◽

10.1186/s13052-021-01088-3 ◽

2021 ◽

Vol 47 (1) ◽

Author(s):

Yuqin Li ◽

Qiu Chen ◽

Wei Ji ◽

Yujie Fan ◽

Li Huang ◽

...

Keyword(s):

Enzyme Linked Immunosorbent Assay ◽

Lung Pathology ◽

Toll Like Receptor ◽

Wild Type ◽

Rt Pcr ◽

Class Switching ◽

Th2 Cytokine ◽

Stat3 Phosphorylation ◽

Hematoxylin And Eosin

Abstract Background To explore the roles of Toll-like receptor (TLR)2 in Th2 cytokine production and immunoglobulin (Ig) class switching following ovalbumin (OVA) sensitization. Methods TLR2−/− and wild-type C57BL/6 mice were sensitized by intraperitoneal injection with OVA. Lung pathology was assessed by hematoxylin and eosin staining. Abundance of interleukin (IL)4, IL5, IL13, and IL21 transcripts in the lungs was quantified by RT-PCR. OVA-specific IgG1, IgG2a, IgG2b, IgE and IgM were quantified by enzyme-linked immunosorbent assay. Phosphorylated signal transducer and activator of transcription (STAT)3 in lung tissue was detected by immunohistochemistry staining and nuclear factor (NF) κB activation was measured by immunofluorescence staining. STAT3 activation was inhibited using cryptotanshinone (CPT) treatment. Germline transcripts (Iμ-Cμ, Iγ-Cγ, Iα-Cα or Iε-Cε), post-recombination transcripts (Iμ-Cγ, Iμ-Cα or Iμ- Cε) and mature transcripts (VHDJH-Cγ, VHDJH-Cα or VHDJH-Cε) were analyzed from splenic B cells of OVA-sensitized wild-type mice (with or without CPT treatment) and TLR2−/− mice (with or without IL21 treatment). Results The lungs of TLR2−/− mice showed a lesser degree of inflammation than wild-type mice after OVA sensitization. Following OVA sensitization, levels of IL4, IL13, and IL21, but not IL5, were significantly lower in TLR2−/− compared with wild-type mice. Moreover, OVA-specific IgG1 and IgE titers were markedly lower and higher, respectively, in TLR2−/− mice. TLR2 deficiency inhibited STAT3 activation but not NF-κB p65 activation. CPT treatment reduced IgG1 titers via inhibition of Stat3 phosphorylation. Both TLR2 knockout and CPT treatment reduced the frequencies of Iγ1-Cγ1, Iγ3-Cγ3 and Iα-Cα transcripts, but IL21 treatment compensated for the effects of TLR2 deficiency. Conclusion These results suggest a role of TLR2 in restricting OVA-sensitized lung inflammation via promotion of IgG1 and inhibition of IgE class switching regulated by IL21 and STAT3.

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DNA Sequences of Small DNA Tumor Viruses, Merkel Cell Polyomavirus and Human Papillomavirus, in Spontaneous Abortion Specimens

10.20944/preprints201811.0366.v1 ◽

2018 ◽

Author(s):

Andrea Tagliapietra ◽

John Rotondo ◽

Ilaria Bononi ◽

Elisa Mazzoni ◽

Federica Magagnoli ◽

...

Keyword(s):

Human Papillomavirus ◽

Spontaneous Abortion ◽

Dna Sequences ◽

Mononuclear Cells ◽

Merkel Cell Polyomavirus ◽

Merkel Cell ◽

Peripheral Blood Mononuclear ◽

Chorionic Villi ◽

Tumor Viruses

Background. The role of viruses in spontaneous abortion (SA) in not completely known. Methods. Merkel cell polyomavirus (MCPyV) and Human papillomavirus (HPV), two small DNA tumor viruses, were investigated in SA. MCPyV/HPV DNAs were investigated by PCR and droplet-digital/quantitative PCRs (ddPCR/qPCR) in chorionic villi and peripheral blood mononuclear cells (PBMCs) from SA females (n=100), the cases, and voluntary interruption (VI, n=100) of pregnancy females, the controls. Results. MCPyV DNAs were detected in 4% and 5% of SA and VI chorionic villi, respectively, with a mean DNA load of 1.99 copy/104 cells in SA and 3.02 copy/10,000 cells in VI (p>0.05). HPV DNAs were detected in 2% of VI chorionic villi, with a mean DNA load of 7.12 copy/cell. Two cases in the VI samples were HPV-45 positive. In PBMCs, MCPyV DNA was detected in 9% and 14% of SA and VI samples, with a mean viral DNA load of 2.09 and 4.70 copy/10,000 cells in SA and VI samples, respectively (p>0.05). None of PBMCs samples tested HPV-positive. Conclusions. MCPyV and HPV DNAs were quantified, for the first time, by ddPCR/qPCR in SA and VI chorionic villi and PBMCs. Data of the present study may help to better understand the role of MCPyV/HPV in SA.

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TLR2 deficiency promotes IgE and inhibits IgG1 class-switching following ovalbumin sensitization

10.21203/rs.3.rs-28854/v2 ◽

2020 ◽

Author(s):

Yuqin Li ◽

Qiu Chen ◽

Wei Ji ◽

Yujie Fan ◽

Li Huang ◽

...

Keyword(s):

Enzyme Linked Immunosorbent Assay ◽

Lung Pathology ◽

Toll Like Receptor ◽

Wild Type ◽

Rt Pcr ◽

Class Switching ◽

Th2 Cytokine ◽

Stat3 Phosphorylation ◽

Hematoxylin And Eosin

Abstract Background: To explore the roles of Toll-like receptor (TLR)2 in Th2 cytokine production and immunoglobulin (Ig) class switching following ovalbumin (OVA) sensitization.Methods: TLR2-/- and wild-type C57BL/6 mice were sensitized by intraperitoneal injection with OVA. Lung pathology was assessed by hematoxylin and eosin staining. Abundance of interleukin (IL)4, IL5, IL13, and IL21 transcripts in the lungs was quantified by RT-PCR. OVA-specific IgG1, IgG2a, IgG2b, IgE and IgM were quantified by enzyme-linked immunosorbent assay. Phosphorylated signal transducer and activator of transcription (STAT)3 in lung tissue was detected by immunohistochemistry staining and nuclear factor (NF) κB activation was measured by immunofluorescence staining. STAT3 activation was inhibited using cryptotanshinone (CPT) treatment. Germline transcripts (Iμ-Cμ, Iγ-Cγ, Iα-Cα or Iε-Cε), post-recombination transcripts (Iμ-Cγ, Iμ-Cα or Iμ- Cε) and mature transcripts (VHDJH-Cγ, VHDJH-Cα or VHDJH-Cε) were analyzed from splenic B cells of OVA-sensitized wild-type mice (with or without CPT treatment) and TLR2-/- mice (with or without IL21 treatment). Results: The lungs of TLR2-/- mice showed a lesser degree of inflammation than wild-type mice after OVA sensitization. Following OVA sensitization, levels of IL4, IL13, and IL21, but not IL5, were significantly lower in TLR2-/- compared with wild-type mice. Moreover, OVA-specific IgG1 and IgE titers were markedly lower and higher, respectively, in TLR2-/- mice. TLR2 deficiency inhibited STAT3 activation but not NF-κB p65 activation. CPT treatment reduced IgG1 titers via inhibition of Stat3 phosphorylation. Both TLR2 knockout and CPT treatment reduced the frequencies of Iγ1-Cγ1, Iγ3-Cγ3 and Iα-Cα transcripts, but IL21 treatment compensated for the effects of TLR2 deficiency.Conclusion: These results suggest a role of TLR2 in restricting OVA-sensitized lung inflammation via promotion of IgG1 and inhibition of IgE class switching regulated by IL21 and STAT3.

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Immunofluorescent staining of histaminase (diamine oxidase) in human placenta.

Journal of Histochemistry & Cytochemistry ◽

10.1177/26.11.102687 ◽

1978 ◽

Vol 26 (11) ◽

pp. 1021-1025 ◽

Cited By ~ 9

Author(s):

C W Lin ◽

C M Chapman ◽

R A DeLellis ◽

S Kirley

Keyword(s):

Intercellular Space ◽

Diamine Oxidase ◽

Intracellular Localization ◽

Immunofluorescent Staining ◽

Frozen Sections ◽

Chorionic Villi ◽

Tissue Sections ◽

Decidual Cells ◽

Tissue Space

An immunofluorescent procedure for the localization of histaminase in human tissue sections has been developed by using a specific antiserum against human placental histaminase. For localization of this enzyme in placental sections, fixation in equal volumes mixture of absolute ethanol and acetone provided the optimum visualization of this enzyme in both frozen sections and paraffin-embedded sections. The immunofluorescent staining of this enzyme in placenta is found to be localized in areas within the maternal decidua, both within the cytoplasm of the decidual cells and in tissue space between the cells. The chorionic villi are completely void of the immunofluorescent stain. Variations in patterns of histaminase localization have been found between term and premature placentas, with the former showing a predominantly intercellular localization and the latter a predominantly intracellular localization. The intercellular localization of this enzyme in the decidua may represent a nonspecific diffusion of the enzyme associated with delivery of the placenta or may reflex a specific functional role of the enzyme in the intercellular space during pregnancy.

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Ultrastructural Changes in Root Cap Cells of Two Australian Native Grass Species Following Exposure to Aluminium

Functional Plant Biology ◽

10.1071/pp96090 ◽

1997 ◽

Vol 24 (2) ◽

pp. 165 ◽

Cited By ~ 6

Author(s):

Simon A. Crawford ◽

Sabine Wilkens

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Root Cap ◽

Ultrastructural Changes ◽

Grass Species ◽

Aluminium Tolerance ◽

Secretory Vesicles ◽

Native Grass ◽

Transmission Electron

Transmission electron microscopy was used to investigate ultrastructural changes in root cap cells of two aluminium-tolerant native grass species, Danthonia linkii Kunth and Microlaena stipoides (Labill.) R.Br., following exposure to Al. Quantitative differences in root cap cells and organelles in response to 0–10 ppm aluminium were determined using image analysis of electron micrographs. Changes to the size of root cap cells due to exposure to Al were similar in the two species with a low Al concentration (1–2 ppm) resulting in larger cells, while higher Al levels (5–10 ppm) reduced cell size. In peripheral cap cells of the more Al-tolerant M. stipoides, the size of secretory vesicles was not affected by exposure to Al, while in peripheral cap cells of the less Al-tolerant D. linkii, exposure to Al resulted in significantly smaller secretory vesicles being produced. Central root cap cells from control plants of M. stipoides contained 90% more dictyosomes and had 50% larger amyloplasts than D. linkii. Measurement of mucilage droplets showed that roots of M. stipoides produced much more mucilage than D. linkii. Exposure of roots of M. stipoides to Al in the range 2–10 ppm had no effect on the size of mucilage droplets produced. The possible role of mucilage production in aluminium tolerance is discussed.

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Molecular Pathology Analysis of SARS-CoV-2 in Syncytiotrophoblast and Hofbauer Cells in Placenta from a Pregnant Woman and Fetus with COVID-19

Pathogens ◽

10.3390/pathogens10040479 ◽

2021 ◽

Vol 10 (4) ◽

pp. 479

Author(s):

Denise Morotti ◽

Massimiliano Cadamuro ◽

Elena Rigoli ◽

Aurelio Sonzogni ◽

Andrea Gianatti ◽

...

Keyword(s):

Molecular Pathology ◽

Nucleocapsid Protein ◽

Positive Staining ◽

Transplacental Transmission ◽

Placental Pathology ◽

Macrophage Marker ◽

Immunodeficiency Virus ◽

Hofbauer Cells ◽

Maternal Fetal Transmission

A small number of neonates delivered to women with SARS-CoV-2 infection have been found to become infected through intrauterine transplacental transmission. These cases are associated with a group of unusual placental pathology abnormalities that include chronic histiocytic intervillositis, syncytiotrophoblast necrosis, and positivity of the syncytiotrophoblast for SARS-CoV-2 antigen or RNA. Hofbauer cells constitute a heterogeneous group of immunologically active macrophages that have been involved in transplacental infections that include such viral agents as Zika virus and human immunodeficiency virus. The role of Hofbauer cells in placental infection with SARS-CoV-2 and maternal-fetal transmission is unknown. This study uses molecular pathology techniques to evaluate the placenta from a neonate infected with SARS-CoV-2 via the transplacental route to determine whether Hofbauer cells have evidence of infection. We found that the placenta had chronic histiocytic intervillositis and syncytiotrophoblast necrosis, with the syncytiotrophoblast demonstrating intense positive staining for SARS-CoV-2. Immunohistochemistry using the macrophage marker CD163, SARS-CoV-2 nucleocapsid protein, and double staining for SARS-CoV-2 with RNAscope and anti-CD163 antibody, revealed that no demonstrable virus could be identified within Hofbauer cells, despite these cells closely approaching the basement membrane zone of the infected trophoblast. Unlike some other viruses, there was no evidence from this transmitting placenta for infection of Hofbauer cells with SARS-CoV-2.

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Morphological Features of Mesenhymal Stroma Cells of Chorionic Villi

Annals of the Russian academy of medical sciences ◽

10.15690/vramn767 ◽

2017 ◽

Vol 72 (1) ◽

pp. 76-83 ◽

Cited By ~ 1

Author(s):

N. V. Nizyaeva ◽

Т. V. Sukhacheva ◽

G. V. Kulikova ◽

M. N. Nagovitsyna ◽

N. E. Kan ◽

...

Keyword(s):

Electron Microscopy ◽

Cell Culture ◽

Mesenchymal Stromal Cells ◽

Stromal Cells ◽

Placental Tissue ◽

Control Group ◽

Chorionic Villi ◽

Mean Values ◽

Hematoxylin And Eosin ◽

Hematoxylin And Eosin Staining

Background: Nowadays autologous mesenchymal placental stromal cells (MSCs) may use to treat for various diseases both of the mother and the child. Stroma of the placenta villi is appropriated origin for cell culture isolation. Aim of the study was to evaluate the possibility for selection and use of placental tissue for mesenchymal stromal cells. Materials and methods: The present study was based on 45 placental samples of women aged 27−38 yy. who underwent surgical delivery at 36−40 weeks of gestation. 30 of these women have been enrolled in the basic group including children with congenital abnormalities (CA). The comparison group consisted of 15 patients with physiological pregnancy. We performed histological examination (with hematoxylin and eosin staining), immunohistochemical examination (with use monoclonal antibodies CD90 (1:25; Abcam, UK), СD105 (1:500; Abcam, UK), CD44 (1:25; Dako), СD73 (1:200, Abcam, UK), and electron microscopy (by microscope Philips/FEI Corporation, Eindhoven, Holland). Eclipse 80i microscope (Nikon Corporation, Japan) was used to examine the immunohistochemical reactions as a brown staining. The evaluation of the intensity of reaction was conducted by NIS-Elements Advanced Research 3.2 program (Czech Republic). Student’s t-test and analysis of variance were used to compare the mean values. Differences were considered statistically significant at p0.05. Results: Interstitial cells of the stroma of the villi with CA had fibroblastic differentiation as revealed degenerative changes of the cells. The histologic examination with hematoxylin and eosin staining revealed significant fibrosis of the stroma of the placenta villi in CA group (p0,01). Immunohistochemical study of stem and intermediate chorionic villi revealed no significant differences in staining of CD44+, СD90+, СD73+, and CD105+ cells if compared to the control group (p0.05). Although CD105 expression was significantly lower in the CA group (0.058±0.0049) than in the control group (0.088±0.0039) (p0.05). However, electron microscopy detected the villi interstitial stromal cells with fibroblastic differentiation in CA group. Conclusions: Thus, it is necessary to exclude placenta with obstetrical history, somatic, and congenital pathology of the mother and the child when selecting the placental cell culture. Moreover, choosing a sample the morphological structure of the placenta should be taken into consideration. However, congenital malformations of the fetus, pathology of the mother cultivate mesenchymal stromal cells of placentas is inappropriate and should be taken advantage of the donor cells.

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