What do we know about fetal-maternal microchimerism?

2021 ◽  
Vol 20 (5) ◽  
pp. 87-92
Author(s):  
I.V. Ignatko ◽  
◽  
M.T. Kazbekova ◽  
D.I. Yakubova ◽  
T.M. Silaeva ◽  
...  
Keyword(s):  
Immune System ◽  
Immune Tolerance ◽  
In Utero ◽  
Host Cells ◽  
Placental Barrier ◽  
Fetal Survival ◽  
Maternal Immune System ◽  
Fetal Microchimerism ◽  
Autoimmune Processes ◽  
The Impact

Microchimerism is a condition characterized by the presence of a small number of foreign cells genetically different from the host cells. Thus, during pregnancy maternal and fetal cells cross the placental barrier, enter the foreign bloodstream and settle in the organs, which leads to the formation of fetal-maternal microchimerism. This review covers some aspects of fetal-maternal microchimerism, including its impact on the course of pregnancy. The existence of fetal micro-chimerism during pregnancy confirms the fact that the maternal immune system interacts with fetal antigens long before delivery. Also, fetal microchimerism may influence the course of auto-immune diseases during pregnancy, which is associated with the fetal-maternal HLA compatibil-ity. Scientists suggest that autoimmune processes that develop after pregnancy are in fact “graft versus host” reactions that occur in response to fetal allogeneic cells. Maternal cells can also cross the placental barrier. This results in the development of tolerance to maternal antigens that are foreign to the fetus. This postnatal immune tolerance is presumably involved in the immuno-suppressive mechanisms that contribute to fetal survival in utero. It has been proven that the fetal immune system is functionally active and is formed in utero due to fetal-maternal microchimerism, non-sterile placental environment under the impact of maternal microbiota and transplacental transfer of immunoglobulins, by inflammatory mediators and cytokines. An important finding is the absence of signs of maternal microchimerism (MMc) in women with preeclampsia. Many questions remain unanswered, therefore, further studies on fetal-maternal microchimerism are needed to assess its impact on the human body. Key words: fetal-maternal microchimerism, immune tolerance, placental barrier, pregnancy, preeclampsia

COVID-19 Vaccines and Dentistry

Dental Update ◽  
2021 ◽  
Vol 48 (1) ◽  
pp. 76-81
Author(s):  
Lakshman Samaranayake ◽  
Kausar Sadia Fakhruddin
Keyword(s):  
Decision Making ◽  
Immune System ◽  
Antibody Response ◽  
Viral Proteins ◽  
Host Cells ◽  
Bad News ◽  
Host Immune System ◽  
Dental Practice ◽  
The Impact ◽  
Gift Wrapping

Transplant pioneer, Peter Medawar, once said that a virus is ‘simply a piece of bad news wrapped in protein’. One could opine then, that the new COVID-19 vaccines are ‘Bits of corona viral proteins in gift wrapping.’ For, most of the COVID-19 vaccines are based on the principle that pre-exposure of the vaccinee's host immune system to the spike proteins of SARS-CoV-2, the first part of the viral anatomy that touches the vulnerable host cells, will elicit an effective antibody response to curb potential future infections. COVID-19 vaccines come in many sizes and shapes, and clearly, a return to normal, post-COVID dental practice entails protecting all members of the dental team with an appropriate vaccine, as and when available. We provide a thumbnail sketch of the COVID-19 vaccines currently in the offing, which we hope will be helpful for decision-making for choice of vaccine. The commentary ends with a discussion of the impact of COVID-19 vaccines on dentistry, in general.

Immunology of pregnancy: cellular mechanisms allowing fetal survival within the maternal uterus

2007 ◽  
Vol 9 (10) ◽  
pp. 1-14 ◽  
Author(s):  
Ana Claudia Zenclussen ◽  
Anne Schumacher ◽  
Maria Laura Zenclussen ◽  
Paul Wafula ◽  
Hans-Dieter Volk
Keyword(s):  
T Cells ◽  
Immune System ◽  
Regulatory T Cells ◽  
Immune Cells ◽  
Heme Oxygenase 1 ◽  
Tolerance Mechanisms ◽  
Cellular Mechanisms ◽  
Fetal Survival ◽  
Maternal Immune System ◽  
Natural Tolerance

AbstractPregnancy success remains a fascinating phenomenon to immunologists as it defies the immunological rules of rejection. Although it was previously thought that the maternal immune system does not see the fetus, it is now well documented that fetal cells reach the maternal body and encounter host immune cells. Natural tolerance mechanisms following this interaction remain to be fully elucidated. This article reviews the current literature on mechanisms of adaptive immunity, with emphasis on regulatory T cells and heme oxygenase 1 (HO-1). We propose a scenario in which regulatory T cells create a tolerant microenvironment at the fetal–maternal interface characterised by the presence of tolerance-associated molecules such as HO-1, which has been shown to be of vital importance for fetal survival.

scholarly journals Collision between Two Pandemics: Obesity and COVID-19 Viral Infection

2021 ◽  
pp. 27-37
Author(s):  
Jehan Saad Alrahimi
Keyword(s):  
Immune System ◽  
Chronic Inflammation ◽  
Complex Disease ◽  
Viral Infections ◽  
Host Cells ◽  
Organ Injury ◽  
Primary Immune Response ◽  
Type I ◽  
Novel Coronavirus ◽  
The Impact

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the novel coronavirus disease 2019 (COVID-19). The principal risk factor for the development of serious forms of COVID-19 was found to be the precarious metabolic health. There are several mechanisms that are implicated in the seriousness of COVID-19 ranging from attenuation of immune system function to chronic inflammation. It is important to keep in mind that obesity is a complex disease when discussing the relation between obesity and the severity of COVID-19. An increasing body of proof links obesity to COVID-19. Obesity has an obvious role in the high incidence, symptoms severity and mortality rates of viral infections seen in obese patients. Adipose tissue shows a high expression of the angiotensin-converting enzyme 2 (ACE2), the receptor for entry of SARS-CoV-2 into host cells, so obese population exhibit higher vulnerability to COVID-19. The primary immune response is offered mainly by type-I interferon (IFN-I) that is suppressed in COVID-19. The pro-inflammatory state associated with obesity produces imbalance of the inflammatory response to COVID-19, as the cytokine storm found in subjects with serious disease form. Obesity is considered as chronic inflammation of low degree, so it shows a capacity for pathogenic immune amplification. In this review, the effect of obesity on the immune system is described. The authors described the dysfunctional immune responses caused by obesity that lead to organ injury in COVID-19 infection and impair the ability of patient to combat the virus. Further research is required to assess the impact of obesity control, immunonutrition and physical exercise in SARS-CoV-2 infection.

Paternal priming of maternal tissues to optimise pregnancy success

2018 ◽  
Vol 30 (1) ◽  
pp. 50 ◽  
Author(s):  
John J. Bromfield ◽  
Jason A. Rizo ◽  
Laila A. Ibrahim
Keyword(s):  
Immune System ◽  
Immune Tolerance ◽  
New Paradigm ◽  
Fetal Tissues ◽  
Maternal Immune System ◽  
The Face ◽  
Specific Antigens ◽  
Maternal Tolerance ◽  
Specific Tolerance ◽  
Fetal Antigen

The question of ‘how does the allogeneic fetus survive gestation in the face of the maternal immune system?’ has yet to be definitively answered. Several acceptable mechanisms exist to facilitate survival of the semi-allogeneic fetus in various species; paramount is the immunological separation of maternal and fetal tissues during gestation. However, keen observation of the maternal immune system during pregnancy has noted maternal immune tolerance to paternal-specific antigens. A mechanism by which the maternal immune system tolerates specific paternal antigens expressed on the fetus would be far more beneficial than the previously proposed immune indolence that would leave the mother susceptible to infection. In species like human or rodent, implantation occurs days after fertilisation and, as such, the mechanisms to establish antigen-specific tolerance must be initiated very early during pregnancy. We and others propose that these mechanisms are initiated at the time of insemination when paternal antigens are first introduced to the maternal immune system. Indeed, a new paradigm demonstrating the importance of paternal–maternal communication at the time of insemination is becoming evident as it relates to maternal tolerance to fetal antigen and ultimately pregnancy success.

Fetal Microchimerism and Women’s Health

2010 ◽  
Vol 13 (4) ◽  
pp. 346-350 ◽  
Author(s):  
Maureen W. Groër ◽  
Maura Manion ◽  
Charles Szekeres ◽  
Nagwa S. El-Badri
Keyword(s):  
Stem Cells ◽  
Immune System ◽  
Women’S Health ◽  
Women's Health ◽  
Malignant Disease ◽  
Term Survival ◽  
Maternal Immune System ◽  
Fetal Microchimerism ◽  
Risk Of Disease

Pregnancy is associated with transfer of maternal cells to the fetus and fetal cells to the mother. In both cases, the transferred cells are described as microchimeric. Fetal microchimeric cells include semi-allogeneic stem cells, which are few in number and are capable of long-term survival in the “foreign” host. They are recognized by the maternal immune system but not rejected or attacked. These cells appear to survive and even thrive for years in a mother’s body, perhaps for her lifetime. Previously regarded as potentially dangerous interlopers that might propagate autoimmune and even malignant disease, fetal microchimeric cells are now increasingly being recognized and analyzed for their healing, reparative, and perhaps regenerative roles. Fetal microchimerism (MC) may make significant and previously unknown positive contributions to women’s health, longevity, and risk of disease. This article reviews the history, major discoveries, and current concepts and gaps in knowledge in the field of fetal MC.

Pregnancy Immunogenetics and Genomics: Implications for Pregnancy-Related Complications and Autoimmune Disease

2019 ◽  
Vol 20 (1) ◽  
pp. 73-97 ◽  
Author(s):  
Hing-Yuen Yeung ◽  
Calliope A. Dendrou
Keyword(s):  
Genetic Variation ◽  
Immune System ◽  
Growth And Development ◽  
System Function ◽  
Uterine Tissue ◽  
Successful Pregnancy ◽  
Immune Systems ◽  
Immune System Function ◽  
Maternal Immune System ◽  
The Impact

Pregnancy presents a singular physiological scenario during which the maternal immune system must accommodate the semiallogeneic fetus. Fluctuations between pro- and anti-inflammatory states are required throughout gestation to facilitate uterine tissue remodeling, fetal growth and development, and finally birth. Tolerance for the fetus must be established and maintained without fundamentally compromising the maternal immune system function, so that both the mother and fetus are protected from foreign insults. Here, we review our current understanding of how genetic variation at both maternal and fetal loci affects implantation and placenta formation, thereby determining the likelihood of a successful pregnancy outcome or the development of pregnancy-related complications. We also consider the impact of pregnancy on both the maternal and fetal systemic immune systems and the related implications for modulating ongoing autoimmune diseases and triggering their development.

Corrigendum to: Paternal priming of maternal tissues to optimise pregnancy success

2018 ◽  
Vol 30 (2) ◽  
pp. 415
Author(s):  
John J. Bromfield ◽  
Jason A. Rizo ◽  
Laila A. Ibrahim
Keyword(s):  
Immune System ◽  
Immune Tolerance ◽  
New Paradigm ◽  
Fetal Tissues ◽  
Maternal Immune System ◽  
The Face ◽  
Specific Antigens ◽  
Maternal Tolerance ◽  
Specific Tolerance ◽  
Fetal Antigen

The question of ‘how does the allogeneic fetus survive gestation in the face of the maternal immune system?' has yet to be definitively answered. Several acceptable mechanisms exist to facilitate survival of the semi-allogeneic fetus in various species; paramount is the immunological separation of maternal and fetal tissues during gestation. However, keen observation of the maternal immune system during pregnancy has noted maternal immune tolerance to paternal-specific antigens. A mechanism by which the maternal immune system tolerates specific paternal antigens expressed on the fetus would be far more beneficial than the previously proposed immune indolence that would leave the mother susceptible to infection. In species like human or rodent, implantation occurs days after fertilisation and, as such, the mechanisms to establish antigen-specific tolerance must be initiated very early during pregnancy. We and others propose that these mechanisms are initiated at the time of insemination when paternal antigens are first introduced to the maternal immune system. Indeed, a new paradigm demonstrating the importance of paternal–maternal communication at the time of insemination is becoming evident as it relates to maternal tolerance to fetal antigen and ultimately pregnancy success.

scholarly journals Tinjauan Molekuler dan Epidemiologi Mutasi pada Virus SARS-CoV-2

bionature ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hartono Hartono ◽  
Yenni Yusuf
Keyword(s):  
Immune System ◽  
Literature Review ◽  
Viral Entry ◽  
Host Cells ◽  
Spike Protein ◽  
Wild Type ◽  
Viral Binding ◽  
Viral Mutation ◽  
Alpha Beta ◽  
The Impact

Abstract. The SARS-CoV-2 virus which is the cause of the COVID-19 pandemic since the end of 2019 has undergone many mutations that gave rise to several variants of concern (VOC) with higher transmission, virulence, and ability to evade the immune system than the initial variant (wild-type). Until now, there are four variants included in the VOC of the virus, namely alpha, beta, gamma and delta variants. The increased transmission and virulence of these VOCs were associated with mutational changes in the spike protein, which is the structure of the virus that plays a role in binding to host cells. In this article, we conduct a literature review on VOCs from the SARS-CoV-2 virus related to mutations that occur and their impact on the viral binding process. To gain an understanding of the impact of mutations in these variants, we also reviewed the structure of the spike protein and the process of viral entry into host cells. Keywords: viral mutation, variants of concern (VOC), COVID-19, SARS-CoV-2.

Uncovering the Diversification of Tissue Engineering on the Emergent Areas of Stem Cells, Nanotechnology and Biomaterials

2020 ◽  
Vol 15 (3) ◽  
pp. 187-201 ◽  
Author(s):  
Sunil K. Dubey ◽  
Amit Alexander ◽  
Munnangi Sivaram ◽  
Mukta Agrawal ◽  
Gautam Singhvi ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Stem Cells ◽  
Immune System ◽  
Clinical Application ◽  
Cell Types ◽  
Patient Specific ◽  
Potential Strategy ◽  
Induced Pluripotent ◽  
Treat All ◽  
The Impact

Damaged or disabled tissue is life-threatening due to the lack of proper treatment. Many conventional transplantation methods like autograft, iso-graft and allograft are in existence for ages, but they are not sufficient to treat all types of tissue or organ damages. Stem cells, with their unique capabilities like self-renewal and differentiate into various cell types, can be a potential strategy for tissue regeneration. However, the challenges like reproducibility, uncontrolled propagation and differentiation, isolation of specific kinds of cell and tumorigenic nature made these stem cells away from clinical application. Today, various types of stem cells like embryonic, fetal or gestational tissue, mesenchymal and induced-pluripotent stem cells are under investigation for their clinical application. Tissue engineering helps in configuring the stem cells to develop into a desired viable tissue, to use them clinically as a substitute for the conventional method. The use of stem cell-derived Extracellular Vesicles (EVs) is being studied to replace the stem cells, which decreases the immunological complications associated with the direct administration of stem cells. Tissue engineering also investigates various biomaterials to use clinically, either to replace the bones or as a scaffold to support the growth of stemcells/ tissue. Depending upon the need, there are various biomaterials like bio-ceramics, natural and synthetic biodegradable polymers to support replacement or regeneration of tissue. Like the other fields of science, tissue engineering is also incorporating the nanotechnology to develop nano-scaffolds to provide and support the growth of stem cells with an environment mimicking the Extracellular matrix (ECM) of the desired tissue. Tissue engineering is also used in the modulation of the immune system by using patient-specific Mesenchymal Stem Cells (MSCs) and by modifying the physical features of scaffolds that may provoke the immune system. This review describes the use of various stem cells, biomaterials and the impact of nanotechnology in regenerative medicine.

Sign in / Sign up

Export Citation Format

Share Document