Immunoreactive alpha A crystallin in rat non-lenticular tissues detected with a sensitive immunoassay method

Biochim Biophys Acta. 1991 Oct 25;1080(2):173-80. doi: 10.1016/0167-4838(91)90146-q.


For the quantitative analysis of the A subunit of alpha crystallin (alpha A) in the lens and for the survey of possible existence of alpha A in the non-lenticular tissues, we have established a highly sensitive and specific immunoassay method for alpha A. Antisera to alpha A were raised in rabbits with alpha A purified from bovine lens, or the C-terminal decapeptide (EEKPSSAPSS) of alpha A (alpha Apep). The antibodies to alpha A and alpha Apep were purified by the use of an alpha A-coupled Sepharose 4B column. The F(ab')2 fragments of purified anti-alpha A IgG were immobilized on polystyrene balls and the Fab' fragments of purified anti-alpha Apep IgG were labeled with beta-D-galactosidase from Escherichia coli. The minimum detection limit of the sandwich-type immunoassay using the two antibody preparations was less than 10 pg alpha A without any cross-reactivity with alpha B. By employing the present methods, it was found that a significant amount of immunoreactive alpha A was present in rat spleen and thymus. Very low levels of immunoreactive alpha A were detected in the rectum, caecum, liver, kidney, adrenal, cerebellum and brainstem. The immunoreactive alpha A in the spleen extract was purified partially (about 50% purity) by the use of anti-alpha Apep-coupled Sepharose. The concentration of alpha A in the spleen was less than 1 ng/mg protein before 3 weeks of age. After 5 weeks of age, however, it increased lineally reaching about 20 ng/mg protein by 18 weeks of age. Immunohistochemically, the alpha A was localized in the reticular cells in the spleen and thymus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Chemistry*
  • Cattle
  • Cross Reactions
  • Crystallins / analysis*
  • Crystallins / immunology
  • Electrophoresis, Polyacrylamide Gel
  • Immunoblotting
  • Immunoenzyme Techniques
  • Immunoglobulin G
  • Immunohistochemistry
  • Lens, Crystalline / chemistry*
  • Macromolecular Substances
  • Male
  • Organ Specificity
  • Rats
  • Rats, Inbred Strains
  • Spleen / cytology*
  • Thymus Gland / cytology*


  • Crystallins
  • Immunoglobulin G
  • Macromolecular Substances