The M‐L blood group system and its influence on red cell potassium levels in sheep

Abstract

SummaryFive phenotypes within the M‐L blood group system of sheep were identified with three reagents: anti‐L(m), anti‐M and anti‐M'. Factor M' only occurred in combination with M. The serological properties were studied and the potassium concentrations in the red cells of the various phenotypes were compared. Like M, the L antigen was only weakly developed on the red cells of newborn lambs, and it was only when adult low potassium levels were established that full L activity was reached. These results support the hypothesis that antigen L is acting as an inhibitor of active potassium transport.

The relationship between the S system of blood groups and potassium levels in red blood cells of cattle

“…Anti-L reagent used for the serological tests was an isoimmune serum obtained by immunizing an HK-type sheep (R502) with homozygous LK-type red cells (Tucker & Ellory, 1970). The antiserum had been absorbed with pooled S-negative red cells from four Jersey cows whose red cells had more than 80 mmol K/litre, and was used at a dilution of 1 in 2.…”

“…The potassium levels of bloods from Friesian calves of six months of age or less are given in Fig. 2. As in lambs (Tucker & Ellory, 1970), there is a tendency for red cells of calves to be incompletely lysed by the various reagents. Some distinc- tions among serological types can be made at early ages, however, and there is little apparent difference in potassium levels among serological types in these calves.…”

“…In sheep there is a straightforward relagonship _between red cell potassium levels and the M system of blood gr6ups. Low>butassium type (LK) red cells have the L blood factor whereas high potassium type (HK) red cells have the M factor; heterozygous LK type cells have both M and L (Rasmusen & Hall, 1966;Tucker & Ellory, 1970). In cattle, preliminary tests have indicated that the S system of blood groups may be analogous to the sheep M system because certain sheep isoimmune anti-M sera can be used to identify certain S system types of cattle red cells (Rasmusen & Hall, 1966;Nguyen, 1972).…”

“…In cattle, preliminary tests have indicated that the S system of blood groups may be analogous to the sheep M system because certain sheep isoimmune anti-M sera can be used to identify certain S system types of cattle red cells (Rasmusen & Hall, 1966;Nguyen, 1972). In addition, Ellory & Tucker (1970) found that some cattle red cells were lysed by sheep anti-L as well as by anti-M, although they found no obvious relationship between the reactions of sheep anti-L and potassium type such as that found in sheep. At a sheep blood group workshop sponsored by the International Society for Animal Blood Group Research, factors M and L were given the new designations Ma and Mb, respectively (Nguyen, 1974).…”

The effect of sheep anti‐L and certain cattle S‐system reagents on active potassium transport in sheep and cattle red blood cells

“…Sheep. Sheep anti-L sera were obtained from 5 different high-potassium type (HK) sheep at various stages of immunization with low-potassium type (LK) sheep red cells (Tucker & Ellory, 1970).…”