You had two blood samples and needed to distinguish between TD and TI B cell responses. You performed a blood test and found that sample 1 was infected with TD antigen and sample 2 with TI and antigen. The results of the analysis showed that sample 1 Select] ( Select ] sample 2 ISelect] V have (select cor High levels of IgG in plasma Affinity of antibodies to antigen increased over time Low levels of membrane-bound IgD on B cells

For each item listed, indicate if it belongs primarily under the category Innate Immunity or the category of Adaptive Immunity: Lysozyme production in mucous membranes [Select] The Complement system [ Select] Inflammatory response [Select] Vaccine-based immunization [Select] Antibody production by activated B ce ✓ [Select] Adaptive Innate +

B lymphocytes require which of the following to become activated and to form plasma cells? 1. recognition and binding of an antigen to the B cell receptor 2. presentation of antigen fragments on the B cell surface by MHC I molecules 3. binding of the B cell to an activated T helper cell Choose one from the following: (A) 1 and 2 (B) 1 and 3 (C) 2 and 3 (D) 1,2 and 3

T-independent humoral immunity may be stunted in children because __________. View Available Hint(s) for Part A       the repertoire of T cells in children is not fully developed T cells are overactive in children children have a weak ability to produce tumor necrosis factor the repertoire of B cells in children is not fully developed

NK Activity (% lysis) 100 80 40 20 O ooo O O BOQ 10 00 20 Depression O 30 p=0.0001 R=0.604 40 FIGURE 4 | Correlation between natural killer (NK) cell activity and depression. There is a significant correlation between NK activity and depression (p = 0.001; R = -0.604).

Addition of immunoglobulin G (IgG) specific for hemoglobin to a solution of hemoglobin results in the formation of a red precipitate. In contrast, addition of the Fab fragments from this antibody to hemoglobin results in no such precipitate. What could explain this difference in results? Treatment with papain produces Fab fragments with different antigen specificity than the original IgG molecule. IgG can simultaneously bind two different antigens, whereas an Fab fragment can only bind one antigen at a time. The Fab fragments preferentially bind to other Fab fragments rather than to hemoglobin. The hemoglobin molecule antibody-binding sites can bind IgG molecules, but cannot bind Fab fragments.

eds Antibodies (Immunoglobulins) Objective 14 Antibodies (immunoglobulins) are glycoproteins secreted by plasma cells. They are located in interstitial fluid, plasma (gamma globulin fraction) and in body secretions. onse A. Antibody Structure Heavy chain Antigen-binding site Light chain Insmakamos Hinge region Complement- binding site Stem region Macrophage binding site OHO (a) Antibody molecule OHO X = Disulfide bond Carbohydrate four polypeptide chains (two heavy, two light) chains are held together by covalent disulfide bonds (S=S) each heavy chain and each light chain has two functional areas: consists of highly variable amino acid sequences which forms the basis of antibody specificity; antigen binds here ????? to more conserved amino acid sequences; there are five basic sequences of amino acids, which define the 5 antibody classes (IgG, IgA, IgM, IgE and IgD); ????? each class has its own characteristic set of effector functions (see next page) Your notes: 4 40 4. 39