Molecular Basis of ABO + Leucocytes

Flashcards about the molecular basis of ABO antigens, leukocytes, and related information.

Name the two categories of Nucleated White Blood Cells (leukocytes)

Neutrophils, Eosinophils, Basophils, Lymphocytes, Monocytes

Which WBC has the fastest response to bacteria?

Neutrophils

What do Neutrophils release to act directly against bacteria?

Lysozymes, defensin proteins, strong oxidants

What do Eosinophils release to slow down inflammation caused by basophils?

Histaminase

What do Basophils release to heighten the inflammatory response?

Heparin, histamine, and serotonin

What are the three main functions of T-Cells?

Attach to antigen bearing cells, release cytokines, and release toxins

What is the main function of B-Cells?

Differentiate into plasma cells and produce antibodies

What is the main function of Monocytes?

Destroy microbes and clean up dead tissue following an infection

What is Chemotaxis?

Movement of an organism in response to a chemical stimulus

What is cell adhesion?

Process by which cells interact and attach to neighboring cells through specialized molecules of the cell surface. Cell adhesion occurs from the interactions between cell-adhesion molecules (CAMs), transmembrane proteins located on the cell surface.

Into what four families are Cell Adhesion Molecules classified?

Integrins, immunoglobulins (Ig) superfamily, cadherins, and selectins

In the ABO blood group system, what are the variable number of alleles?

A, B, and O

What are the two antigens in the ABO blood group system?

Antigen A and antigen B

What are the two antibodies in the ABO blood group system?

Antibody A and antibody B

What are ABO substances?

Complex oligosaccharides

What are some functions of glycoproteins?

Hormones, antibodies, enzymes, structural components of extracellular matrix, lysosomal enzymes, secretory proteins, receptors

How is the carbohydrate chain extended during glycoprotein synthesis?

Sequential addition of sugar residues to the nonreducing end

Name some sugar-nucleotides used for glycoprotein formation

UDP-glucose, UDP-galactose, UDP-glucuronic acid, UDP-xylose, UDP-N-acetylglucosamine, UDP-N-acetylgalactosamine, CMP-N-acetylneuraminic acid, GDP-fucose, GDP-mannose

Describe the Synthesis of O-linked glycosides

Protein is synthesized in the RER and extruded into the lumen, glycosilation begins with the transfer of an N- acetylgalactosamine into the R group of a serine or threonine residue, transfer of N-acetylgalactosamine occurs from UDP-acetylgalactosamine, glycosiltransferases responsible for the stepwise synthesis of oligosaccharades

Describe the Synthesis of N-linked glycosides

Protein synthesis begins and the polypeptide chain is extruded into the endo- plasmic reticulum (ER). A branched oligosaccharide is synthesized bound to dolichol pyrophosphate. The oligosaccharide is transferred from dolichol to an asparagine residue of growing polypeptide chain. Trimming of the carbohydrate chain begins as the protein moves through the ER. In the Golgi, further trimming and/or addition of monosaccharides occurs.

What are glycolipids?

Molecules that contain both carbohydrate and lipid components

What are glycolipids derivatives of?

Derivatives of ceramides in which a long-chain fatty acid is attached to the amino alcohol spingosine

What are some functions of glycolipids?

Intracellular communication, cell recognition factors, cell surface receptors

What are the two types of neutral glycolipids?

Ceramide monosaccharides (cerbrosides) and ceramide oligosaccharides (globosides)

What are the two types of acidic glycolipids?

Gangliosides and Sulfatides

How do the H, A, B, and O genes affect blood group substances?

The H gene codes for a fucosyltransferase, which adds fucose to a peripherial galactose in the heterosaccharide precursor; The A allele encodes N-acetylgalactosamine glycosyltransferase; The B allele a galactosyltransferase; The O allele an inactive protein.