OTHER BLOOD GROUPS

2. OTHER BLOOD GROUPS DR MOHAMMED H SAIEM ALDAHR Faculty of Applied Medical Sciences MED TECH DEP. 3RD YEAR MT

3. OTHER BLOOD GROUP SYSTEMS • Terminology • A blood group system is a group of Ags produced by alleles at a single locus or at loci so closely linked that crossing over not occur or is very rare. • They are (blood group genes) located on the autosomal chromosomes and are inherited in straight forward mendeline fashion • Most blood group alleles are co-dominant and express a corresponding Ag. • Silent or amorphic alleles that produce no Ag are rare. When paired chromosomes carry the same silent allele, a null phenotype results.

4. OTHER BLOOD GROUP SYSTEMS • MNSs Blood Group System MNSs: Ab are usually a mixture of IgM and IgG Usually give dosage effect (variability of reactivity) • Dosage effect usually strong reaction with red cells from homozygous (MM) individuals and weak with red cells that are heterozygous (MN) • Anti-M does not cause transfusion reaction because of its low thermal range • Anti-N is naturally occurring IgMcold agglutinin range. • It does not cause transfusion reaction or HDN.

5. OTHER BLOOD GROUP SYSTEMS • Anti-S : Can be IgM or IgG • Anti-s: IgG • Anti-S and Anti-s can cause hemolytic transfusion reaction and HDN

6. OTHER BLOOD GROUP SYSTEMS • P Blood Group System (Labile with storage) • The genes code for transferases that attach a specific sugar to glycolipids on red blood cell membrane. • The Ags formed are P1, Pk, and P • Red cells that have no P1, Pk, and PAgs are termed p. • The serum of these individuals usually contains an Ab that reacts with the P1, Pk, and P Ag. • This Ab is called anti-Tja.

7. OTHER BLOOD GROUP SYSTEMS • P Antibodies • Anti-P1 • Naturally occurring IgM, allo-antibody frequently found in the serum of P2 individuals • Ab can be enhanced by enzyme treated cells • Can be clinically significant if it has a thermal range above 30 oC.

8. OTHER BLOOD GROUP SYSTEMS • Anti-P • Can occur as allo or auto-antibody • Allo-Ab is IgM, naturally occurring Ab with high thermal range • Found in the serum of Pk and p individuals. • Auto-Ab is an IgG biphasic Ab associated with Paroxysmal cold hemoglbinuria (P.C.H).

9. OTHER BLOOD GROUP SYSTEMS • Anti-Tja • Is a combination of anti-P and P1 anti-Pk produced by p individuals. • It can be IgM or IgGand can cause transfusion reaction and HDN

10. OTHER BLOOD GROUP SYSTEMS • The I Blood Group System • The I and i antigens are found on nearly all red cells. • The I Ag is present in large amount on the red cells of adults, but only small quantities on red cells of newborns • Ii Antibodies • Are IgM, naturally occurring auto-agglutinins with low thermal range. • They are not clinically significant unless they react above 30oC.

11. OTHER BLOOD GROUP SYSTEMS • The I Blood Group System • An increase in the titer of anti-I is frequently found in patients with Mycoplasma pneumonae infections. • Anti-I is rarely found in healthy individuals, but can form secondary to viral infection such as infectious mononucleosis. • It is usually not clinically significant but can cause hemolysis if it has a thermal range.

12. OTHER BLOOD GROUP SYSTEMS • DUFFY System Ag are far less common in blacks Can be neutralized by enzymes such as (ficin, papain, bromelin). Phenotype Frequency (Blacks) Fy (a+b-) 9% Fy (a+b+) 1% Fy (a-b+) 22% Fy (a-b-) 68%

13. OTHER BLOOD GROUP SYSTEMS • KIDD System Can be implicated in HDN and Warm AIHA 50% of delayed hemolytic transfusion reaction are due to Kidd Abs Phenotype Jk (a+b-) Jk (a+b+) Jk (a- b+) Jk (a- b-)

14. OTHER BLOOD GROUP SYSTEMS • LUTHERAN System • Can be both IgG and IgM • Anti-Lub tends to be more clinically significant. Phenotype Lu (a+b-) Lu (a+b-) Lu (a- b+)