Ubiquitinated Hepatitis D Antigen-Loaded Microvesicles Induce a Potent Specific Cellular Immune Response to Inhibit HDV Replication in Vivo

Hepatitis D is the most severe viral hepatitis with accelerating the process of liver cirrhosis and increasing the risk of hepatocellular carcinoma. However, there are no effective antiviral drugs.

The changing trend of alloimmunization in antenatal females: experience from a tertiary care centre in north-western India

Background: Haemolytic disease of the foetus and new-born (HDFN) is a major concern during the antenatal period, especially in countries with low human development index (HDI). The guidelines for antenatal screening and management significantly vary from one geographical region to another. Since the introduction of RhIG immunoprophylaxis, the incidence of HDFN caused by alloimmunization to D antigen has markedly reduced, while that caused by other minor blood group antigens has not been addressed significantly and needs to be given due consideration.Methods: The study was carried out to evaluate the incidence of alloimmunization and analyse various factors associated with HDFN in north-western India. A total of 1700 antenatal cases were evaluated over a period of 20 months, antibody screening and identification was performed on their samples and results were analysed.Results: Out of the 1700 cases, 21 were detected to have the presence of an alloantibody with a prevalence of 1.24%. Out of these, 11 were Rh (D) negative while the remaining 10 were Rh (D) positive. The rate for alloimmunization was higher in females who had a history of blood transfusion (1.24%), bad obstetric history (1.24%), and multigravida status (1.24%).Conclusions: Screening all pregnant females for alloimmunization to RBC antigens, irrespective of their Rh status will help in minimizing the incidence of the HDFN. The practice of providing partial phenotype matched blood to the females of the childbearing age group should be encouraged to reduce the overall incidence of alloimmunization and HDFN.

Prevalence of Some Common Human Traits: An Updated Survey Report From Rajshahi University Campus, Bangladesh

Prevalence of some common human traits viz., body weight, height and body mass index (BMI), pattern baldness, body hair, chin, colour blindness, cheek dimples, earlobes, length of index finger, lips, nose, polydactyly, tongue and widow’s peak, and ABO blood groups along with their Rh-D antigen, were recorded and analyzed from 500 male and 1000 female students of the Rajshahi University (RU) Campus. Results showed that body weights of the male students (66.42±8.92 kg) were significantly higher (t= 35.14; P<0.001) than those of the female students (51.64±6.97 kg). The differences in BMI between males (23.32±3.26) and females (20.85±2.63), as expected, were also highly significant (t= 15.79; P<0.001) and notably, some of the female students were underweight (BMI< 18.5). No female had baldness compared to 15.8% bald males. Sparse body hair was prevalent over the dense body hair in both genders. The females had much higher smooth chin (89.6%) than the males (58.0%) but the males had much higher cleft chin (42.0%) compared to the females (10.4%). No female was colourblind whereas 7.4% males were colourblind. Absence of dimples was recorded in 92.4% males and 85.7% females. Attached earlobes were higher than the free earlobes in both sexes. Compared to the length of the ring finger, shorter index finger was prevalent both in males (85.4%) and females (68.6%). Frequencies of the broad lips in males and females were 53.4% and 58.6%, respectively. Females dominated large and broad noses (76.1%) in comparison with their male counterparts (61.4%). Polydactyly was a rare trait in the Campus, where only 2.2% males and 0.2% females had extra digits in their hands or feet. Tongue rollers (53.8%) outnumbered the tongue folders in males, but tongue folders (54.4%) outnumbered the tongue rollers in females. Males with widow’s peak were higher (25.8%) than that in the females (19.0). Blood groups in the males and females were in the order: B (32.0) > O (29.8) > A (22.4) > AB (15.8) and O (34.8) > B (34.4) > A (21.9) > AB (8.9), respectively. As a whole, 85.4% males and 98.0% females were Rh-positive where the blood group phenotypes did not affect body weight, height and BMI of the subjects (r=0.012; P=0.63). The relevance of these findings to the physical, physiological, social and clinical well-being of the humans has been discussed. Bangladesh J. Zool. 49 (2): 215-228, 2021

Rhesus Negative Pregnancy: Prevalence and Foetomaternal Outcomes in a Tertiary Hospital, South-South Nigeria

Rhesus incompatibility can pose a problem in pregnancy and cause obstetric failure in a handful of women. The Rhesus factor is a red blood cell surface antigen; and there are many antigen subtypes that make up the Rhesus blood group systems, of which the most commonly involved and most immunogenically associated with Rhesus isoimmunisation is the D antigen. The objective of this study is to determine the prevalence of Rhesus negativity and the foetomaternal outcomes at the Federal Medical Centre, Yenagoa, Bayelsa State, Nigeria. This was a 5-year retrospective study conducted between 1st January, 2016 and 31st December, 2020 at our Obstetric Unit. Data were retrieved, entered into a pre-designed preformed and analyzed using SPSS version 25.0. Results were presented as mean and standard deviation for continuous variables and frequencies or percentages for categorical variables. Of the 4,571 pregnant women, 104 were Rhesus negative, giving a rate of 2.27%. The most common blood group among the women (53.8%) and their partners (84.6%) was the O blood group. Only 2 (1.9%) women were sensitised. Out of the 104 Rhesus negative women, 81 were unsensitised (77.9%) and received anti-D immunoglobulin. Majority of the babies had a good outcome, though 19 (18.2%) of them were admitted into the special care baby unit for various conditions. The incidence of Rhesus negative pregnancy in our study was 2.27%, and 1.9% of the women were sensitised. Prompt administration of anti-D immunoglobulin after sensitising events and post-delivery is key in the prevention of Rhesus isoimmunisation.

DEL in China: the D antigen among serologic RhD-negative individuals

Background Providing RhD-negative red cell transfusions is a challenge in East Asia, represented by China, Korea, and Japan, where the frequency of RhD-negative is the lowest in the world. Findings Among 56 ethnic groups in China, the RhD-negative frequency in Han, the prevalent ethnicity, is 0.5% or less, similar to most other ethnic groups. The Uyghur ethnic group has the highest reported RhD-negative frequency of up to 4.7%, as compared to 13.9% in the US. However, an estimated 7.15 million RhD-negative people live in China. The RhD-negative phenotype typically results from a loss of the entire RHD gene, causing the lack of the RhD protein and D antigen. The DEL phenotype carries a low amount of the D antigen and types as RhD-negative in routine serology. The DEL prevalence in RhD-negative individuals averages 23.3% in the Han, 17% in the Hui and 2.4% in the Uyghur ethnicities. The Asian type DEL, also known as RHD*DEL1 and RHD:c.1227G > A allele, is by far the most prevalent among the 13 DEL alleles observed in China. Conclusion The purpose of this review is to summarize the data on DEL and to provide a basis for practical strategy decisions in managing patients and donors with DEL alleles in East Asia using molecular assays.

RHD Genotyping of Rh-Negative and Weak D Phenotype among Blood Donors in Southeast Iran

Background: The D antigen is a subset of Rh blood group antigens involved in the hemolytic disease of the newborn [HDFN] and hemolytic transfusion reaction [HTR]. The hybrid Rhesus box that was created after RH gene deletion, was known as a mechanism of the Rh-negative phenotype. Hybrid marker identification is used to confirm the deletion of the RHD gene and to determine zygosity. This study aims to detect this marker in Rh-negative and weak D phenotype blood donors of the southeast of Iran. Materials and Methods: The molecular analysis of the hybrid Rhesus box was performed on the 200 Rh-negative blood donors in Sistan and Baluchestan province, southeast Iran. The presence of alleles responsible for the D variants was assessed by DNA sequencing in 26 weak D phenotype donors. Results: Of the 200 Rh-negative blood samples, 198 samples were homozygous (99%), and two samples were heterozygous (1%). Heterozygous samples had RHD*01N.73 allele and the RHD*01N.18 allele. Of the 26 samples with weak D phenotype, 16 partial DLO (61%), 4 partial DBT1 (15.3%), 2 partial DV type 2 (7.7%), 1 weak D type 1, 1 weak D type 4.2.3, 1weak D type 105 and 1 RHD (S103P) (4%) were determined. Conclusion: Since RHD gene deletion is the main mechanism of the Rh-negativity in Sistan and Baluchestan provinces, a hybrid Rhesus box marker can be used in resolving RhD typing discrepancies by RHD genotyping methods.

Rhesus negative males have an enhanced IFNγ-mediated immune response to influenza A virus

The Rhesus D antigen (RhD) has been associated with susceptibility to several viral infections. Reports suggest that RhD-negative individuals are better protected against infectious diseases and have overall better health. However, potential mechanisms contributing to these associations have not yet been defined. Here, we used transcriptomic and genomic data from the Milieu Interieur cohort of 1000 healthy individuals to explore the effect of RhD on immune responses. We used the rs590787 SNP in the RHD gene to classify the 1000 donors as either RhD-positive or -negative. Whole blood was stimulated with LPS, polyIC, and the live influenza A virus and the NanoString human immunology panel of 560 genes used to assess donor immune response and to investigate sex specific effects. Using regression analysis, we observed no significant differences in responses to polyIC or LPS between RhD-positive and -negative individuals. However, upon sex-specific analysis, we observed over 30 differentially expressed genes (DEGs) between RhD-positive (n=401) and RhD-negative males (n=78). Interestingly these Rhesus-associated differences were not seen in females. Further investigation, using gene set enrichment analysis, revealed enhanced IFNγ signalling in RhD-negative males. This amplified IFNγ signalling axis may explain the increased viral resistance previously described in RhD-negative individuals.

Allo-Anti-D vs. Auto-Anti-D in Females of Child Bearing Years: The Critical Role of Rh Genotyping

Introduction/Objective In females of child-bearing years, establishing accurate D-antigen identification is critical; this can be further complicated when a D+ patient seemingly develops an allo-anti-D. We present a unique case series highlighting the critical role of genotyping in distinguishing allo-anti-D vs. auto-anti-D. Methods/Case Report Case 1: An African American, 21-year-old, nulliparous female with a history of sickle cell disease presented for transfusion. The patient’s blood type was O, Rh Positive on multiple testing platforms (ORTHO VISION® Analyzer, 1001 US Highway 202, Raritan, NJ 08869, and Immucor, Inc., 3130 Gateway Drive, Norcross, GA 30071). On type and screen performed by manual tube testing, anti-D was identified. DAT IgG was weakly positive. The patient’s phenotype had been performed previously, and she was negative for both the C and E antigens. Genotyping results: RhD homozygote. RHD*DAU0 and RHD*DIVa type 3. The patient was determined to have auto-anti-D formation. Case 2 A 42-year-old female presented for routine prenatal care. At a previous facility, the patient tested as D+ and typed as O, Rh Positive (ORTHO VISION® Analyzer). An anti-D pattern was identified. Due to the patient’s Rh+ history and early pregnancy status, no Rh immune globulin was administered. A sample was sent to the reference laboratory which confirmed D+ status and a pattern of anti-D. The current titer was 8. Genotyping results RhD hemizyote. Positive for hybrid Rhesus box associated with deletion of RhD and RHD*DIVa, Go(a+). The patient was determined to have an allo-anti-D. Results (if a Case Study enter NA) NA Conclusion These two cases highlight the importance of RhD genotyping for resolutions of anti-D. In case 1, the patient had two altered alleles. While DIVa, type 3, is associated with anti-D formation, she also expressed RhD*DAU0 which is not considered to lack D proteins. We report the rare association between DAU0 expression and auto-anti-D formation.

Improved library preparation protocols for amplicon sequencing-based noninvasive fetal genotyping for RHD-positive D antigen-negative alleles

Objective We aimed to simplify our fetal RHD genotyping protocol by changing the method to attach Illumina’s sequencing adaptors to PCR products from the ligation-based method to a PCR-based method, and to improve its reliability and robustness by introducing unique molecular indexes, which allow us to count the numbers of DNA fragments used as PCR templates and to minimize the effects of PCR and sequencing errors. Results Both of the newly established protocols reduced time and cost compared with our conventional protocol. Removal of PCR duplicates using UMIs reduced the frequencies of erroneously mapped sequences reads likely generated by PCR and sequencing errors. The modified protocols will help us facilitate implementing fetal RHD genotyping for East Asian populations into clinical practice.