INTRODUCTION: Pregnant women are reported to be at increased risk of severe coronavirus disease 2019 (COVID-19) due to underlying immunosuppression during pregnancy. However, the clinical course of COVID-19 in pregnancy and risk of vertical and horizontal transmission remain relatively unknown. We aim to describe and evaluate outcomes in pregnant women with COVID-19 in Singapore. METHODS: Prospective observational study of 16 pregnant patients admitted for COVID-19 to 4 tertiary hospitals in Singapore. Outcomes included severe disease, pregnancy loss, and vertical and horizontal transmission. RESULTS: Of the 16 patients, 37.5%, 43.8% and 18.7% were infected in the first, second and third trimesters, respectively. Two gravidas aged ≥35 years (12.5%) developed severe pneumonia; one patient (body mass index 32.9kg/m2) required transfer to intensive care. The median duration of acute infection was 19 days; one patient remained reverse transcription polymerase chain reaction (RT-PCR) positive >11 weeks from diagnosis. There were no maternal mortalities. Five pregnancies produced term live-births while 2 spontaneous miscarriages occurred at 11 and 23 weeks. RT-PCR of breast milk and maternal and neonatal samples taken at birth were negative; placenta and cord histology showed non-specific inflammation; and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulins were elevated in paired maternal and umbilical cord blood (n=5). CONCLUSION The majority of COVID-19 infected pregnant women had mild disease and only 2 women with risk factors (obesity, older age) had severe infection; this represents a slightly higher incidence than observed in age-matched non-pregnant women. Among the women who delivered, there was no definitive evidence of mother-to-child transmission via breast milk or placenta.
Abortion, Spontaneous/epidemiology* ; Adult ; COVID-19/transmission* ; COVID-19 Nucleic Acid Testing ; COVID-19 Serological Testing ; Cohort Studies ; Disease Transmission, Infectious/statistics & numerical data* ; Female ; Fetal Blood/immunology* ; Humans ; Infectious Disease Transmission, Vertical/statistics & numerical data* ; Live Birth/epidemiology* ; Maternal Age ; Milk, Human/virology* ; Obesity, Maternal/epidemiology* ; Placenta/pathology* ; Pregnancy ; Pregnancy Complications, Infectious/physiopathology* ; Pregnancy Outcome/epidemiology* ; Pregnancy Trimester, First ; Pregnancy Trimester, Second ; Prospective Studies ; RNA, Viral/analysis* ; Risk Factors ; SARS-CoV-2 ; Severity of Illness Index ; Singapore/epidemiology* ; Umbilical Cord/pathology* ; Young Adult

This study looked into a family involving a rare mother-child ABO blood type inconsistency and explored its genetic and molecular basis. In the family, the mother had type AB blood and the father was blood type B and they gave birth to a baby of blood type O. Their blood types were phenotypically identified by using different techniques, including micro-column gel test, immune inhibition test, absorption and elution tests. The sequences of all 7 exons of ABO allele from the core family members were determined by using PCR and clone-based sequencing. The loci of mutated gene were compared against normal human genes. The result showed that the mother's erythrocytes were agglutinable with monoclonal anti-A antibody (2+) and had agglutination reaction with anti-B antibody (4+). The mother's serum registered agglutination action with standard blood type A cells. The findings showed an ABO inconsistency. When domestic antibodies were used, the mother's erythrocytes yielded agglutination reaction with humanized anti-B serum (4+) and anti-B monoclonal antibody but were non-agglutinable with humanized anti-A serum and anti-A monoclonal antibody. Upon absorption and elution, the titer of anit-A antibody was 128 both before and after the absorption test, with no significant difference found between pre- and post-absorption values. Our results confirmed that the mother's allelic gene was type B and contained type A. The father's blood type was type B, and son's blood type was type O. Clone-based sequencing revealed that the mother carried a heterozygous gene of B101.01 (ntA640→G)/O01, which contained an M214→V mutation that could express a weak expression of antigen A, resulting in blood type AB. However, their son did not have the M214→V mutation, which yielded a false ABO-inconsistency between him and his mother. We were led to conclude that type B gene with a M214→V mutation can encode both antigen B and weak antigen B that can lead to false ABO-inconsistencies.
ABO Blood-Group System ; genetics ; immunology ; Adult ; Base Sequence ; DNA Primers ; Female ; Humans ; Maternal-Fetal Exchange ; Molecular Sequence Data ; Mutation ; Polymerase Chain Reaction ; Pregnancy ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid

PURPOSE: This study aimed to compare the regulatory T cells in cord blood of appropriate for gestational age (AGA) neonates with those of small for gestational age (SGA) neonates. MATERIALS AND METHODS: Umbilical cord blood was collected upon labor in 108 healthy full-term (between 37 and 41 gestational weeks) neonates, who were born between November 2010 and April 2012. Among them, 77 samples were obtained from AGA neonates, and 31 samples were obtained from SGA neonates. Regulatory T cells and lymphocyte subsets were determined using a flow cytometer. Student's t-test for independent samples was used to compare differences between AGA and SGA neonates. RESULTS: Regulatory T cells in cord blood were increased in the SGA group compared with normal controls (p=0.041). However, cytotoxic T cells in cord blood were significantly decreased in the SGA group compared with normal controls (p=0.007). CONCLUSION: This is the first study to compare the distribution of lymphocyte subsets including regulatory T cells in cord blood between AGA neonates and SGA neonates.
Biological Markers/metabolism ; Female ; Fetal Blood/*immunology ; Gestational Age ; Humans ; Infant, Newborn/*blood ; Infant, Small for Gestational Age/*blood ; Lymphocyte Count ; T-Lymphocytes, Cytotoxic/metabolism ; T-Lymphocytes, Regulatory/*metabolism

The study was aimed to investigate the effect of anti-mouse CD122 antibody on the hematopoietic repopulating capacity of cord blood CD34⁺ cells in a humanized murine model-non obese diabetic/severe combined immunodeficiency (NOD/SCID) mice. After sublethal irradiation with γ-ray, NOD/SCID mice were intraperitoneally injected with 200 µg mouse isotype control antibody or anti-mouse CD122 antibody. Human cord blood CD34⁺ cells or phosphate-buffered saline (PBS) were injected via the tail vein at 6-8 hours later. Cohort of the mice injected with anti-mice CD122 antibody or control antibody alone were sacrificed at different time point (at week 2, 3, and 4 weeks) after the injection, and the percentage of NK cells in the peripheral blood was analyzed by flow cytometry. To evaluate the effect of anti-mouse CD122 antibody on the repopulating capacity of cord blood CD34⁺ cells in the recipient mice, phenotype analysis was performed in the bone marrow at 6 and 8 weeks after the transplantation. The results showed that the proportion of NK cells in the peripheral blood were (4.6 ± 0.6)% and (5.7 ± 1.7)% at week 2 and 3 after anti-CD122 antibody injection respectively,which decreased by 60%, compared with the mice injected with isotype control antibody. After 6 and 8 weeks of cord blood CD34⁺ cell transplantation,the percentage of human CD45⁺ in the bone marrow of the recipient mice treated with anti-mice CD122 antibody was (63.0 ± 12.2)% and (53.2 ± 16.3)%,respectively,which were dramatically higher than that in the mice treated with isotype control antibody (7.7 ± 3.6)% and (6.1 ± 2.4)%. Moreover,at 8 weeks after transplantation,human CD34⁺ cells appeared significantly in the recipients treated with anti-CD122 antibody. It is concluded that the anti-mouse CD122 antibody enhances the hematopoietic repopulating capacity of cord blood CD34⁺ cells in the NOD/SCID mice through decreasing the proportion of NK cells.
Animals ; Antibodies ; immunology ; Antigens, CD34 ; Bone Marrow ; Cord Blood Stem Cell Transplantation ; Fetal Blood ; immunology ; Hematopoietic Stem Cell Transplantation ; Hematopoietic System ; cytology ; immunology ; Humans ; Interleukin-2 Receptor beta Subunit ; immunology ; Killer Cells, Natural ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Transplantation, Heterologous

This study was purposed to comparatively analyze the early T-lymphocyte subsets and T-cell receptor excision cycles (TREC) reconstruction in recipients with hematologic malignancies after myeloablative unrelated cord blood transplantation (UCBT) and sibling donor bone marrow and/or peripheral blood stem cell transplantation (BMT/PBSCT). The peripheral blood T lymphocyte subsets were detected using flow cytometry and TREC were detected using real-time quantitative PCR for 40 patients with hematologic malignancies in the first six months after myeloablative allogenic hematopoietic stem cell transplantation. The results showed that in the first month after transplantation, the absolute counts of CD3(+), CD3(+) CD4(+), CD3(+) CD8(+) cells were lower significantly in the UCBT group than those in the BMT/PBSCT group. And later the absolute counts of CD3(+), CD3(+)CD4(+), CD3(+)CD8(+) cells were not different between two groups. The ratio of CD3(+)T subset in the peripheral blood lymphocytes of the UCBT recipients was lower, but the difference was not statistically significant within 2 months after transplantation. The ratio of CD3(+)CD4(+) cells in the patients received the UCBT and BMT/PBSCT decreased obviously since engraftment happened. The CD3(+)CD4(+) cells on the 2 months after transplantation fell to the lowest level, then gradually increased, but did not reach to the normal level until 6 months after transplantation. CD3(+)CD8(+)cells were well reconstituted, rising to normal at the engraftment after transplantation, with a low CD4(+): [KG-*2] CD8(+) ratio over the first 6 months after transplantation. Compared with the BMT/ PBSCT group, the naive T cells (CD3(+)CD4(+)CD45RA(+)CD62L(+)) were more in the first month after transplantation and the terminally differentiated effector memory T cells (CD3(+)CD4(+)CD45RA(+)CD62L(-)) were more at the 3 month after transplantation in the UCBT group, and those were significantly more than the normal control group. TREC were lower and did not recovered until 6 months after transplantation in the recipients of the two groups. It is concluded that compared with sibling donor's BMT/PBSCT, early T cell reconstitution significantly delayed after UCBT, but the terminally differentiated effector memory T cells are higher after transplantation, and thus play a anti-infective or anti-leukemia role.
Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Fetal Blood ; transplantation ; Hematopoietic Stem Cell Transplantation ; methods ; Humans ; Male ; Receptors, Antigen, T-Cell ; immunology ; T-Lymphocyte Subsets ; immunology ; Young Adult

Puma (P53 upregulated modulator of apoptosis) is a BCL-2 homology 3 (BH3)-only BCL-1 family member and a critical mediator of P53-dependent and -independent apoptosis. Puma plays an essential role in the apoptosis of hematopoietic stem cells exposed to irradiation without an increased risk of malignancies. This study was purposed to develop an effective lentiviral vector to target Puma in human hematopoietic cells and to investigate the effect of Puma gene knockdown on the biological function of human cord blood CD34(+) cells. SF-LV-shPuma-EGFP and control vectors were constructed, and packaged with the pSPAX2/pMD2.G packaging plasmids via 293T cells to produce pseudo-type lentiviruses. SF-LV-shPuma-EGFP or control lentiviruses were harvested within 72 hours after transfection and then were used to transduce human cord blood CD34(+) cells. GFP(+) transduced cells were sorted by flow cytometry (FCM) for subsequent studies. Semi-quantitative real time RT PCR, Western blot, FCM with Annexin V-PE/7-AAD double staining, Ki67 staining, colony forming cell assay (CFC), CCK-8 assay and BrdU incorporation were performed to determine the expression of Puma and its effect on the cord blood CD34(+) cells. The results showed that Puma was significantly knocked down in cord blood CD34(+) cells and the low expression of Puma conferred a radio-protective effect on the cord blood CD34(+) cells. This effect was achieved through reduced apoptosis and sustained quiescence after irradiation due to Puma knockdown. It is concluded that knockdown of puma gene in CD34(+) hematopoietic stem cells of human cord blood possesses the radioprotective effect, maintains the cells in silence targeting Puma in human hematopoietic cells may have a similar effect with that on mouse hematopoietic cells as previously shown, and our lentiviral targeting system for Puma provides a valuable tool for future translational studies with human cells.
Antigens, CD34 ; immunology ; Apoptosis Regulatory Proteins ; genetics ; Fetal Blood ; cytology ; Flow Cytometry ; Gamma Rays ; Genetic Vectors ; HEK293 Cells ; Hematopoietic Stem Cells ; cytology ; immunology ; radiation effects ; Humans ; Lentivirus ; genetics ; Proto-Oncogene Proteins ; genetics

OBJECTIVETo evaluate the effects of endothelial cell- targeted soluble Notch ligand hD1R protein on expansion and engraftment of cord blood hematopoietic stem/progenitor cell (CB HSPCs).

METHODSRecombinant hD1R protein was first induced and purified. Human cord blood CD34⁺ cells were co-cultured on human umbilical vein endothelial cells (HUVECs) supplemented with a cocktail containing 5 types of human cytokines including TPO, SCF, FL, IL-6, IL-3 (5GF) and soluble hD1R. The expansion of CD34⁺ cells was tested under different culture conditions including PBS group (PBS replaces HUVEC), hD1R group, sup group (HUVEC supernatant replaces HUVEC), fix group (fixed HUVEC replaces HUVEC), Day 0 group (Control). Cell cycle and apoptosis of cultured cells were also analyzed. Their progeny expanded in PBS or hD1R group were transplanted into sublethally irradiated NOD/SCID mice. The percentages of human CD45⁺ (hCD45⁺) cells in the marrow of recipient mice were determined by FACS 12 weeks later.

RESULTShD1R induced more expansion in the total number of CD34⁺ cells cocultured with HUVECs plus 5GF, which was 87.50-fold increase compared to the Day 0 group, and 7.98-fold increase than that of PBS group. FACS analysis also showed that the percentage of CD34⁺ cells was 77.0% in G0/G1 phase in the hD1R group, which indicated that hD1R enhanced HSPCs expansion and inhibited apoptosis. Moreover, hD1R significantly promoted human HSPC engraftment after BM transplantation in irradiated mice.

CONCLUSIONThe Notch-mediated ex vivo expansion system has been established and hD1R promoted expansion and engraftment of human CB HSPCs, which provided the evidence for further clinical application.

Animals ; Antigens, CD34 ; Cells, Cultured ; Coculture Techniques ; Endothelial Cells ; immunology ; Fetal Blood ; Hematopoietic Stem Cells ; immunology ; Humans ; Membrane Proteins ; immunology ; Mice

OBJECTIVETo investigate the influence of maternal atopy on cord blood effector T cells and to identify these biologic markers as predictors of atopic dermatitis (AD).

METHODSSeventy mother-infant pairs were recruited in this prospective birth cohort study. Suspected factors for allergy, including maternal allergic history, total serum IgE, and maternal age at birth, were collected. Mother peripheral blood samples and cord blood were obtained and assayed for the percentage of interferon-γ (IFN-γ) and interleukin 4 (IL-4) producing T cells(Th1 and Th2 respectively) using flow cytometry. Their offspring at the age of 2 years old were evaluated by their dermatologist whether they had AD. Statistical analysis was performed using multiple logistic regression models and receiver-operating characteristic curve was employed to predict atopic dermatitis.

RESULTSTwenty-one allergic and 49 nonallergic mothers were recruited in this study. During the first two years of life, 15.7% children (n = 11) developed a physician-diagnosed AD (all children were the only child in the family). In group with maternal allergic rhinitis, a significantly increased percentage of Th2 was observed in peripheral blood of mother (7.10[1.18;16.1]% vs. 0.37[0.25;0.72]%, U = 10.0, P < 0.05) and cord blood of newborns (1.02[0.57;1.34]% vs. 0.21[0.15;0.42]%, U = 127.5, P < 0.05), respectively. Maternal atopic history did not affect the percentage of Th1 cells in cord blood (0.69[0.40;1.12]% vs.0.50[0.31;0.66]%, U = 361.0, P > 0.05). Children with reduced Th1/Th2 ratio in cord blood had a higher risk to develop AD (OR = 1.72, P = 0.001) . The model including Th1/Th2, maternal allergy, maternal age at birth and maternal total IgE showed high ability to discriminate children with and without AD. AUC was 0.907 (95% CI: 0.804-1.011, P < 0.001).

CONCLUSIONSElevated IL-4⁺CD4⁺ T cells in cord blood were of relevance with maternal allergic history. Imbalance between Th1 cell and Th2 cell at birth are associated with maternal allergy and promoted subsequent AD development.

Adult ; Child, Preschool ; Dermatitis, Atopic ; immunology ; Female ; Fetal Blood ; cytology ; Flow Cytometry ; Humans ; Immunoglobulin E ; blood ; Infant ; Infant, Newborn ; Mothers ; Prospective Studies ; Rhinitis, Allergic ; blood ; immunology ; Th1 Cells ; cytology ; Th1-Th2 Balance ; Th2 Cells ; cytology

OBJECTIVETo observe the anti-virus effects of andrographolide (AD) on the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) signaling pathway when immunological cells were infected with H1N1.

METHODSLeukomonocyte was obtained from umbilical cord blood by Ficoll density gradient centrifugation, and immunological cells were harvested after cytokines stimulation. Virus infected cell model was established by H1N1 co-cultured with normal human bronchial epithelial cell line (16HBE). The optimal concentration of AD was defined by methyl-thiazolyl-tetrazolium (MTT) assay. After the virus infected cell model was established, AD was added into the medium as a treatment intervention. After 24-h co-culture, cell supernatant was collected for interferon gamma (IFN-γ) and interleukin-4 (IL-4) enzyme-linked immunosorbent assay (ELISA) detection while immunological cells for real-time polymerase chain reaction (RT-PCR).

RESULTSThe optimal concentration of AD for anti-virus effect was 250 μg/mL. IL-4 and IFN-γ in the supernatant and mRNA levels in RLRs pathway increased when cells was infected by virus, RIG-I, IFN-β promoter stimulator-1 (IPS-1), interferon regulatory factor (IRF)-7, IRF-3 and nuclear transcription factor κB (NF-κB) mRNA levels increased significantly (P<0.05). When AD was added into co-culture medium, the levels of IL-4 and IFN-γ were lower than those in the non-interference groups and the mRNA expression levels decreased, RIG-I, IPS-1, IRF-7, IRF-3 and NF-κB decreased significantly in each group with significant statistic differences (P<0.05).

CONCLUSIONSThe RLRs mediated viral recognition provided a potential molecular target for acute viral infections and andrographolide could ameliorate H1N1 virus-induced cell mortality. And the antiviral effects might be related to its inhibition of viral-induced activation of the RLRs signaling pathway.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Antiviral Agents ; pharmacology ; Cells, Cultured ; Coculture Techniques ; DEAD Box Protein 58 ; DEAD-box RNA Helicases ; genetics ; metabolism ; Dendritic Cells ; drug effects ; immunology ; virology ; Diterpenes ; pharmacology ; Fetal Blood ; cytology ; Humans ; Influenza A Virus, H1N1 Subtype ; drug effects ; immunology ; Influenza, Human ; drug therapy ; immunology ; virology ; Interferon-beta ; genetics ; metabolism ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Leukocytes, Mononuclear ; drug effects ; immunology ; virology ; Macrophages ; drug effects ; virology ; NF-kappa B ; genetics ; metabolism ; Promoter Regions, Genetic ; drug effects ; immunology ; RNA, Messenger ; metabolism ; Signal Transduction ; drug effects ; genetics ; immunology

BACKGROUNDCell transplantation has great potential for promoting endothelial repair and reducing the complications of percutaneous coronary intervention (PCI). The aim of this study was to investigate the effect of transplantation of human umbilical cord blood endothelial progenitor cells (EPCs) on injured arteries.

METHODSUmbilical cord blood mononuclear cells were obtained from post-partum lying-in women, and EPCs were isolated, cultured, expanded and identified by immunofluorescence. The carotid arterial endothelium of New Zealand white rabbits was injured by dilatation with a 3F balloon, and the EPCs were injected into the lumen of the injured artery in the transplanted group (n = 16), while an equal volume of phosphated buffered saline (PBS) was injected into the control group after balloon injury (n = 16). The animals were sacrificed after either 2 or 4 weeks, and the grafted cells were identified by double immunofluorescence staining with human nuclear antigen (HNA) and CD31 antibodies. Arterial cross sections were analyzed by pathology, immunohistochemistry and morphometry to evaluate the reparative effects of EPCs. Proliferating cell nuclear antigen (PCNA) and transforming growth factor (TGF)-β1 mRNA expression were detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSFluorescence-labeled EPCs were found in the neointima. The neointimal area and the neointimal/medial area ratio were significantly lower in the transplanted group than in the control group (P < 0.05). von Willebrand factor (vWF) immunohistostaining showed more VWF-positive cells in the transplanted animals than in the controls (8.75 ± 2.92 vs. 4.50 ± 1.77, P < 0.05). Compared with the control group, the transplanted group had lower expression of PCNA mRNA (0.67 ± 0.11 vs. 1.25 ± 0.40, P < 0.01) and higher expression of TGF-β1 mRNA (1.10 ± 0.21 vs. 0.82 ± 0.07, P < 0.05).

CONCLUSIONSEPCs derived from human umbilical cord blood were successfully transplanted into injured vessels. The transplanted EPCs inhibited neointimal hyperplasia and promoted vascular re-endothelialization.

Animals ; Carotid Artery Injuries ; immunology ; pathology ; therapy ; Cell Differentiation ; Cells, Cultured ; Cytokines ; genetics ; Endothelial Cells ; cytology ; physiology ; Fetal Blood ; cytology ; Humans ; Hyperplasia ; Male ; Neointima ; pathology ; Proliferating Cell Nuclear Antigen ; genetics ; RNA, Messenger ; analysis ; Rabbits ; Stem Cell Transplantation ; Transforming Growth Factor beta1 ; genetics