Ligand affinity chromatography was used to purify a cell surface alpha 2-macroglobulin (alpha 2M) receptor. Detergent extracts of human placenta were applied to an affinity matrix consisting of alpha 2M, previously reacted with methylamine, coupled to Sepharose. Elution with EDTA specifically released polypeptides with apparent molecular masses of 420 and 39 kD. In some preparations, small amou...

Human class I transplantation antigens are cell-surface-expressed molecules composed of one glycosylated, membrane-integrated heavy chain and one nonglycosylated, water-soluble subunit, beta 2-microglobulin (beta 2m). We have examined the intracellular transport of the two subunits by microinjecting mRNA into Xenopus laevis oocytes. Beta 2m, translated in oocytes, was transported and secreted i...

Cytotoxic T lymphocytes (CTL) can recognize antigenic peptides bound in a groove formed by the alpha 1 and alpha 2 domains of the heterodimeric major histocompatibility complex class I molecule. Proper assembly, transport, and stability of functional class I molecules is thought to require beta 2 microglobulin (beta 2m), the light chain of the class I heterodimer. We show here that the requirem...

Despite being an ancient disease, leprosy remains a public health problem in several countries -particularly in India, Brazil and Indonesia. The current operational guidelines emphasize the evaluation of disability from the time of diagnosis and stipulate as fundamental principles for disease control: early detection and proper treatment. Continued efforts are needed to establish and improve qu...

Endogenous opioid peptides take part in various functions as hormones or neuromodulators. In 1979, Takagi and his co-workers identified a new morphine-like substance “kyotorphin” (Kyo) a dipeptide synthesized in specific brain regions. The highest levels were found in the lower brain stem and dorsal spinal cord areas closely associated with the pain regulatory system. The peptide binds to a spe...