AB Rh Research Articles

Distribution of abo and rhesus (D) blood groups in Kano metropolis

Background : To provide information in the distribution of ABO and Rhesus (D) blood groups since there has been no such study carried out in Kano. Study Population/Method : A total of 5,303 blood donors and pregnant women who came for antenatal care at Aminu Kano Teaching Hospital, Kano between January and December, 2003 were determined by Dacie and Lewis method. Result : Blood group O had the highest distribution of 55.3%, followed by similar result of 20.8% and 207% of blood groups A and B respectively while blood group AB had the lowest distribution of 3.2%. The prevalence of Rh(D) negative subjects amongst the population studied was 5.1%. Similar result were obtained when the distribution of A Rh (D) positive, A Rh (D) negative, B Rh (D) positive, B Rh(D) negative, O Rh(D)positive and O Rh (D)negative(20.1%, 1.3%, 19.6%,1.1%, 50% and 2.3% respectively) of pregnant women were compared to 19.6%, 0.83%, 19.7%, 1.0%, 53.9%,and 3.% respectively of blood donor. However, striking differences were observed when AB Rhesus (D) positive (5.4%) and AB Rh(D) negative (0.24%) of pregnant women were compared to 1.6% and 0.1% respectively of blood donors. Conclusion : Similar result of ABO and Rhesus (D)blood groups distribution have been observed in this study when compared to previous studies in Nigeria. However, there is a need for further study to be carried out with regard to tribes since ethnicity and inter-tribal marriage have been found by earlier authors to influence the ABO and Rhesus blood groups distribution most especially in the urban areas. Keywords : distribution, ABO and rhesus (D) groups, Kano Highland Medical Research Journal Vol. 3(2) 2005: 139-143

Age of blood in inventory at a large tertiary care hospital.

This major tertiary care centre transfers over 1000 red cell units monthly. Units are rotated as part of inventory management to ensure minimum wastage. In 1998, the expiration date of AS3 red cells was extended from 35 to 42 days, potentially affecting inventory. The average age of the red cell units in inventory on any given day was evaluated to determine whether the extended expiration date would affect blood availability and to determine the feasibility of using blood at different ages for various purposes. Over a 6-month duration, 20 days were selected for review: units were categorized according to ABO group and Rh type and then analysed for age within certain categories. The average age of the blood in inventory was 1 to 2 weeks. The probability of having units less than 1-week old was highest for Group O and zero for Group B Rh(+) and Group AB Rh(+). More than 60% of the O Rh(-) blood was older than 28 days. The age of units in inventory varies with respect to ABO group, Rh type and weekday. In practice, the stock rarely reaches 42 days of age. Future studies on the effects of age of blood on patient outcome must consider the logistics of supply and the availability of blood of each group. Transfusion of large numbers of units of the same age and of a specific blood group and type may not always be possible.

Determination of fetal RhD status by maternal plasma DNA analysis.

In this study, we assessed the feasibility of fetal RhD genotyping by analysis of cell-free fetal DNA(cffDNA) extracted from plasma samples of Rhesus (Rh) D-negative pregnant women by using real-time polymerase chain reaction (PCR). Fetal genotyping was performed on 30 RhD-negative women between 9 and 39 weeks of gestation who were referred to us for invasive testing [amniocentesis/chorionic villi sampling (CVS)]. The fetal RHD genotype was determined based on real-time PCR method. Exons 7 and 10 of the RHD and SRY genes were targeted. Among the pregnant women, 12 were carrying male and 17 were carrying female fetuses. Out of 29 pregnant women, 21 had RhD-positive and nine had RhD-negative fetuses. One sample )case 12, whose blood group was found to be AB Rh [+] (was excluded due to controversial results from repeated serological analyses. All prenatal results were in concordance with postnatal RhD status and fetal sex without false- positive or -negative results. Performing real-time PCR on cffDNA showed accurate, efficient and reliable results, allowing rapid and high

DEFECTIVE REDUCING ACTIVITY OF NEWBORN PLATELETS

Activation of platelet(Plt)plasma membrane is associated to Cytochrome C(Cyt.C)reducing activity.We studied this activity in newborn Plts stimulated by low or high molar ADP, collagen,thrombin and opsonized-zymosan(opZ).Cord blood was collected from placental end of the cut umbelical cord.The platelet-rich plasmas(PRPs)were layered on Ficoll 23%(w/v) to eliminate leukocyte contamination.Zymosan was opsonized with adult citrated-plasma(AB Rh-).Cyt.C reduction was determined spectrophotometrically,and aggregation(in PRPs or Plt suspensions)by the change in light transmission.The Cyt C reduction was undetectable(n=20)in newborn Plts stimulated with all stimuli(adult controls:10-20 nmol/109 Plts/10 min)including collagen(4 μg/ml)and thrombin(1.67 U/ml)able to induce their aggregation.Newborn Plts did not aggregate after low molar concentrations of agonists(Hathaway,1970)or after immunologic stimulation(Del Principe,ESPHI 1985).opZ plus subthreshold ADP elicited a 90% aggregation, but not Cyt.C reduction.The defective membrane redox reactions reflect an alteration in the process leading to membrane activation,and possibly account for the impaired functional response of newborn platelets.

Immunoglobulin subclass (IgG3) restriction of anti-P and anti-Pk antibodies in patients of the rare p blood group.

Serum antibodies against globoside and ceramide trihexoside, two major glycolipids in human erythrocytes, were investigated in 29 individuals with the rare p blood group. Antibodies of the IgM and of the IgG3 classes were detected. In AB Rh(-) blood donors, who were not of the p blood group, low levels of antibodies of the IgM class were found against P and Pk, whereas no antibodies were detected in cord blood. The increased number of spontaneous abortions and stillbirths observed among the p individuals may relate to the presence of IgG3 antibodies, because such antibodies pass the placental barrier and are efficient in complement activation and in mediating antibody-dependent cytotoxicity.

Membrane associated antigens of human malignant melanoma V: Serological typing of cell lines using antisera from nonhuman primates

Antisera against various melanoma cell lines were raised in nonhuman primates (Cercopithecus aethiop.). After exhaustive absorption with AB Rh + red blood cells and pooled platelets from about 200 donors the sera were still reactive to various degrees in the microimmune adherence test with other melanoma lines, with embryonic fibroblasts, and with non-melanoma lines. As proven by absorption experiments, the main-specificity of the antisera was not directed against components of the fetal calf serum used for cell culture or against mycoplasma grown from commercial fetal calf serum. In addition, no cross-reactivity was observed with Bacillus Calmette-Gerin, and in blocking experiments no reactivity against extracts of common bacterial antigens or mixed molds was detected. Absorption with embryonic fibroblasts or embryonic tissue showed that the reactivity of most antisera was directed against melanoma-associated antigens expressed also on fetal tissue. It was not possible to determine whether the remaining reactivity on some cell lines was melanoma-specific or directed against fetal antigens not contained in the fetal material used for absorption. Cross-absorption of antisera with other melanoma cells revealed that various cell lines express different patterns of tumor-associated antigens with no, or only partial, overlap. The cross-absorption experiments made it possible to type the cell lines according to their surface antigens and arrange the cell lines in order according to the degree of mutual antigenic relationship.

Membrane associated antigens of human malignant melanoma. III. Specificity of human sera reacting with cultured melanoma cells

Sera from melanoma patients, healthy donors, pregnant women and patients with types of tumors other than melanoma were tested on various melanoma lines as well as on a cultured brain tumor and adult skin fibroblasts, using a microimmune adherence test. Positive reactions against all cell lines were found in serum from each group of donors. The degree of reactivity was dependent on the cell line used. Sequential absorption with AB Rh+ and pooled platelets of more than 200 donors either reduced the titer of sera or rendered a great part of the sera negative, demonstrating that antibodies against HL-A antigens and other tissue antigens were involved. The remaining positive sera were further absorbed with pooled cells from 6- to 8-week-old fetuses. This step abolished the reactivity of most sera, indicating the relatively high frequency of antibodies in males and females against fetal antigens expressed also on melanoma and other cells. In order to determine the specificity of the few remaining positive sera, absorptions with three different melanoma cell lines, a brain tumor and fibroblasts were carried out. The results showed only partial cross-reactivity between different cell lines. No evidence was obtained from this study for the existence of a common cross-reacting membrane-associated antigen on human malignant melanoma. Antigens that could be readily detected seemed mostly to be tumor-associated fetal antigens.

An antigenic relationship between kidney and certain Escherichia coli strains.

By means of double diffusion analyses supplemented with absorption experiments an antigenic relationship was shown between human kidney and three out of nine tested <i>E.coli</i> strains. Antiserum to bacteria of these strains (serotypes O2:K1:H4, O14:K7:H- and O22:K13:H1) precipitated with kidney antigen from three adults and one infant, and antiserum to human kidney precipitated with veronal buffer extract antigens from the 3 <i>E.coli</i> strains. The veronal buffer extract antigen from the O2 strain contained at least 2 such antigenic factors, one related to the O2 lipopolysaccharide and another which was present also in the O22 and the O14 strains in an antigenically identical or related form. No antigens related to the tested <i>E.coli</i> strains were found in spleen, liver or AB Rh( + ) red cells. A possible significance of this antigenic relationship between kidney and some <i>E.coli</i> strains for the pathogenesis of the renal parenchymal reduction and scarring processes observed in some cases of pyelonephritis is proposed.

Congenital Ovarian Cyst and Erythroblastosis Fetalis

To the Editor:— Ovarian tumors are uncommon in pediatric practice and very rare in the newborn. An extensive reference survey failed to reveal any cases occurring in connection with erythroblastosis fetalis. A white female baby, born spontaneously at term on Feb 2, 1964, weighed 6 lb 12 oz (3.04 kg). The mother, age 27, had had no miscarriages, and there were two other children, ages 6 and 5. The pregnancy was uneventful, but because the mother was known to have AB Rh negative blood, titers were run and the indirect Coombs test on Jan 18, 1964, was 1:2048. The baby was referred to the Missouri Methodist Hospital and Medical Center two hours after birth. Cord blood revealed a total bilirubin of 5.4 mg/100 cc, and shortly after admission it was 20 mg/100 cc on baby's blood, with a hemoglobin level of 16.6 gm/100 cc. The baby's abdomen was large and

A heretofore unreported agglutinable human blood factor and its possible relationship to blackwater fever.

Summary It appears that a new human agglutinable blood factor has been demonstrated by the use of chimpanzee-immune serum developed in rabbits. The presence in 97 per cent of all healthy white group O individuals and 97.4 per cent of all healthy group O negroes studied strongly suggested that it is not associated with the AB, MN, Rh-Hr, or P systems. While we are not certain as to the usefulness of this factor it appears from previous work that its absence is intimately associated with the etiology of blackwater fever. It is possible that this factor may explain the unaccounted for reactions following the transfusion of compatible bloods of both AB group and Rh type.