Which of the following is NOT a protective outcome of antibody-antigen binding?

A direct ELISA test is utilized as a pregnancy test because it tests for:

(NCLEX/HESI/TEAS)

a. antibodies to the fetus in urine.

b. antibodies to a pregnancy hormone in urine.

c. an antigen that recognizes a pregnancy hormone in urine.

d. T cells that recognize a pregnancy hormone in urine.

e. the presence of a pregnancy hormone in urine.

Describe one difference between a direct ELISA and an indirect ELISA.

Which term describes antibodies binding to a virus preventing it from attaching to host cells?

The study of antigen-antibody reactions is referred to as _____.

DRAW IT Label components of the direct and indirect ELISA tests in the following situations. Which test is direct? Which test provides definitive proof of disease?

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How does the antigen in an agglutination reaction differ from that in a precipitation reaction?

Put the following in the correct sequence to elicit an antibody response: (1) TH cell produces cytokines; (2) B cell contacts antigen; (3) antigen fragment goes to surface of the B cell; (4) TH recognizes antigen fragment and MHC; (5) B cell proliferates.

a. 1, 2, 3, 4, 5

b. 5, 4, 3, 2, 1

c. 3, 4, 5, 1, 2

d. 2, 3, 4, 1, 5

e. 4, 5, 3, 1, 2

Explain the effects of excess antigen and antibody on the precipitation reaction. How is the precipitin ring test different from an immunodiffusion test?