Abstract: - ABO blood group is determined by the presence or absence of A and B antigens on the surface of RBC

and of anti-A and anti-B antibodies in the serum. The relatively weak expression of A and B antigens in newborns

due to their developing immune systems poses challenges in accurately detecting naturally occurring IgM

antibodies against these antigens. This difficulty in immunoserological methods contributes to the potential for

errors in determining the blood groups of newborns. Despite this, the Rh antigen expression in newborns remains

comparable to that in adults. Nonetheless, various factors contribute to diverse blood typing results in newborns,

including the utilization of alternative testing methods. The complexity of blood typing is magnified when using

samples from the umbilical vein. Furthermore, compared to adults, the exploration of ABO antigen expression in

newborns and were typed by forward and reverse blood typing methods with monoclonal antibodies and srandart

erythrocytes. The distribution of phenotypic groups within the ABO system among the newborns was not uniform.

The r allele was identified with the highest frequency in the analyzed samples (0.6), while the prevalence of the p

allele significantly lags at 0.3. The q allele has the lowest frequency (0.1). In our study, we propose that for the

majority of cases (43.94±3.5%) among the studied newborns, there was an absence of naturally occurring anti-A

and anti-B antibodies (n=87). In a specific scenario, within the O(I) blood group nwborns, partial synthesis of these

antibodies was detected in 14.14±2.4% (n=28). Meanwhile, 41.92±3.5% of the newborns in our study exhibited

natural antibodies similar to those found in adults. We didn’t find any difficulties in typing the Rh blood group

antigens in the newborns. In conclusion, our study's findings indicate that newborns, in certain instances, exhibit

strongly pronounced natural anti-A and anti-B antibodies within the ABO system. However, in the majority of

Blood group antigens are considered to play a role in

how well the biological species of Homo sapiens has

Transfusion (ISBT) recognizes a total of 45 blood

group systems encompassing 360 antigens for human

red blood cells, [4].

polysaccharides, though they can also be proteins or

complexes of proteins, carbohydrates, and lipids.

Blood group antigens are primarily involved in the

trophic and regulatory functions of blood cells. Due

to their presence within cell receptors, they play a

antigens of the ABO system, which were also the

first blood groups to be recognized, [6]. Among the

nearly 45 blood group systems investigated thus far,

the identification of these systems and the subsequent

revelation of naturally occurring antibodies targeting

antigens absent on certain cells explained the prior

inconsistencies in blood transfusion and organ

transplantation. This breakthrough paved the way for

safer transfusion practices in situations of critical

inherent and predominantly IgM class. These

antibodies are generated without antigen stimulation,

unlike those produced during the conventional

adaptive immune response. The exact nature of their

production remains a subject of debate. Anti-ABO

IgM is usually not present in newborns but appears in

the first year of life. The antibodies may be produced

against food and environmental antigens (bacteria,

viral, or plant antigens), which are similar in structure

to A and B antigens, [9], [10].

ABO typing discrepancy. The AB (IV) group is

typically determined first, followed by the A (II) or B

(II) group a week later. In some circumstances,

different blood types are identified using distinct

alternative techniques in the same sample of

newborns.

there exists an increased potential for errors when

ascertaining the blood group from samples obtained

through the umbilical vein in newborns, which is the

received more extensive attention compared to the

analysis conducted in newborns. Notably,

information about to A1 and A2 subgroups is limited

in its availability.

study was to thoroughly investigate various facets of

blood group characterization in newborns. This

encompassed a comprehensive analysis, involving

the identification of A1, A2, B, H, and D antigens on

the surface of red blood cells (RBCs), alongside the

approach is crucial for reducing the potential for

errors and inaccuracies in blood group determination,

ultimately leading to more reliable and precise

results.

Newborns’ blood samples were collected from the

"M. Iashvili Batumi Maternal and Child Central

Hospital" and "Iris Borchashvili Health Center

Medina", in accordance with the approved ethical

and AB) and two types of Rh system (Rh+ and Rh-)

based on this method. Agglutination processes were

meticulously observed and recorded, following

standardized protocols and guidelines. The standard

erythrocytes with A and B blood groups and

newborns’ plasma were taken for reverse methods for

ABO blood system natural antibodies (anti-A and

anti-B) typing. Agglutination reaction was observed

with the naked eye, but in some cases, especially in

cases of so-called “weak” agglutination reaction, we

platform, [17].

Determining the blood group of a newborn is an

essential laboratory test conducted shortly after birth.

It involves obtaining biological material from either

the umbilical cord or the peripheral blood of the

newborn. However, it is crucial to exercise caution

and take special care when collecting blood from the

umbilical cord to avoid potential contamination.

Contamination can adversely impact the serological

expression of antigens, leading to false agglutination

distribution characteristic has A (II) blood group.

41.35±3.4% of the studied newborns have A (II)

blood group phenotypical characteristics

(n=86). B(III) blood groups have 21 studied

newborns (10.10±2.0%) and only 10 studied

newborn’s blood samples show both A and B

antigens specifications and 4.8 ±1.4% of the studied

newborns have AB (IV) blood group. There are four

categories - O (I), A (II), B (III), AB (IV) and based

on these degrees of freedom (df) is - 3. One variable

(n=9). The degrees of freedom (df) is equal to 3 in

this particular case. Chi-square (χ2) equals 16.6,

which is 2.12 times more than Critical Values

(CV=7.815). The P-value is < .00001. The result is

significant at p < .05 (Table 3).

*df – Degrees of freedom; * χ2 - Chi-square; *CV-

Critical values

Adult persons with A (II) blood group in the plasma

have natural anti-B antibodies. We find that 40.7

±3.4% case studied newborns have the anti- B

antibodies in the plasma as an adult (n=35), but the

majority of them 59.3±5.2% (n=51) did not show any

agglutination reaction with standard erythrocyte mass

with B blood group, which means that there weren’t

.05.

*df – Degrees of freedom * χ2 - Chi-square *CV- Critical

values

In our current study we found that unlike the adults,

in some studied newborns, ABO blood group system

A and B antigens are poorly expressed on the surface

of the red blood cell. In the majority of cases, we

used the optic microscope with low and/or high

poorly expressed at the newborn stage we will follow

the genetic mechanism of the expression of

erythrocyte ABO antigens in the surface of the red

blood cell. The main reason is that for the synthesis

of the mentioned antigens, stepwise biochemical

reactions are needed. Because the mentioned antigens

are chemically carbohydrates and are not direct

products of the specific genes, and accordingly,

special transferases are formed first, which then

change the structure of the precursor substance on the

genetic inheritance of the ABO blood group system

A and B antigens is due to multiple alleles and is one

of the solid genetic traits. Usually, they do not change

residue to the terminal chain of the galactose

oligosaccharide. Transferases encoded by genes A

and B can attach the corresponding immunodominant

sugar residues to galactose, but only if the fucose

residues are already attached (i.e., the middle chain

has already been transformed to the H antigen). A

and B antigen-determining carbohydrates

reciprocally reduce the number of H-antigen

molecules, [18].

typing showed A or O phenotypical

characteristics. The gorillas were shown B

phenotype specification. The expression of A and B

antigens here is like humans, but lower primates do

not have these characteristics. Interestingly, they

express A and B antigens in respiratory or digestive

epithelium. In some cases, it is also expressed in the

biological secrets, especially in the saliva, [19].

at an early stage of embryogenesis can be found in

vesicle (yolk sac) nearly 14 days after fertilization.

development of the embryo and fetus. During

embryonic and fetal life, erythropoiesis occurs in two

different types. The first form consists of nucleated

erythroblasts that form the formation process going

erythrocytes that differentiate processes going in the

embryonic liver and fetal bone marrow, [25], [27],

[28], [29]. After is the formation of RBCs antigens,

compare our current study information with the

available literature. In all studies, it is mentioned that

newborns have specific ABO antigen and antibody

expression, but it is not described in detail O, A, B

blood group newborns antibodies prevalence and

compared to adults. If this antibody synthesis process

is related to food and environmental antigens we

think that this current study will be different from

other regions' newborns' study. All regions have their

specific diet and environmental conditions.

the first few days of postnatal life. All errors can be

detected by this method, [31].

embryonic life by using the amniotic fluid, which is

collected from the amniocentesis from 12 to 28

weeks of gestation. Scientific research has shown

that

correlated with the secretory status of the newborn,

which is determined from the saliva (98% of cases),

blood group in the newborns, because in all cases of

the Rh+ samples D antigen was well agglutinated

with monoclonal antibodies. The reason is that

the Rh antigen is the direct product of the RhD gene,

[37], [38].

The ABO antigens and antibodies expression process

starts prenatally and continues postnatally, especially

during the first six months. We suggested that in

some cases newborns have normal expression of

ABO antibodies as adult, but they are not expressed

[8] J. Milland and M. S. Sandrin, «ABO blood

[9] D. R. Branch, «Anti-A and anti-B: what are

[12] S. B. Abegaz, «Human ABO Blood Groups

[13] H.-Y. Li and K. Guo, «Blood Group Testing»,

[15] S. Mu, C. Sha, S. Ren, and D. Xiang, «Clinical

[16] S. Fathima and R. B. Killeen, «ABO Typing