M T Ch17 AdaptiveImmunity s

7/25/2019 M T Ch17 AdaptiveImmunity s

1/33

17AdaptiveImmunity:Specific

Defenses

of the Host


2/33

Copyright 2010 Pearson Education, Inc.

SLOs

Differentiate between innate and adaptive iunity, and huora! and ce!!u!ar iunity.

Define antigen, epitope, and hapten.

E"p!ain the function of antibodies and describe their structura! and cheica!characteristics. #ae one function for each of the five c!asses of antibodies.

Copare and contrast $%dependent antigens and $%independent antigens.

Differentiate between p!asa ce!! and eory ce!!.

Describe c!ona! se!ection.

Describe how a huan can produce different antibodies.

Describe four outcoes of an antigen%antibody reaction.

Differentiate between he!per $ and cytoto"ic $

Define apoptosis.

Define antigen%presenting ce!!.Describe the ro!e of antibodies and natura! &i!!er ce!!s in antibody%dependent ce!!%

ediated cytoto"icity.

Identify at !east one function of each of the fo!!owing' cyto&ines, inter!eu&ins, interferons.

Distinguish a priary fro a secondary iune response.

Contrast the four types of adaptive iunity.


3/33


Immune System Overview

Innate immunity' (n individua!)s genetica!!y

predeterined resistance to certain diseases.

Adaptive immunity' (bi!ity of the body to react tospecific icrobia! infection.

(daptive iunity is antigen specific, has eory

is ade up of two branches

Humoral Immunity*+ ce!! ediatedCellular Immunity*$ ce!! ediated

co!!aborates with innate iunity

hasabi!ity to ignore hea!thy -se!f o!ecu!es*tolerance


4/33


oca!ulary

Anti"en*(g' ( substance that causes the body to

produce specific antibodies or sensiti/ed $ ce!!s. Anti!ody*(b' Proteins ade in response to an (g

can cobine with that (g.

Serolo"y' $he study of reactions betweenantibodies and antigens.

Antiserum' ( generic ter for seru because itcontains (b.

#lo!ulins' eru proteins

Iunog!obu!ins * 3aa * g!obu!ins' eruantibodies

Cop!eent'


5/33


Serum $roteins

Fig 17.18


6/33


(ntibodiesrecogni/e andreact with

antigenicdeterinants orepitopeson anantigen

Fig 17.1

Anti"ens and

anti"enic

Determinants

%he &ature of Anti"ens


7/33Copyright 2010 Pearson Education, Inc.

Haptens Fig 17.2

Definition' a!! separab!e part of an antigen thatreacts specifica!!y with an antibody but is incapab!eof stiu!ating antibody production e"cept incobination with a carrier protein o!ecu!e



%he &ature of Anti!odies

Fig 17.3

Iunog!obu!in tructure' 4 po!ypeptide chains *2

heavy and 2 !ight 5ariab!e regions

Constant regions

Fig 17.3



I"#anti!odies 'onomer

()* of serum anti!odies

Activate complement

In !lood+ lymph+ and intestine

Cross placenta

,nhance pha"ocytosis- neutrali.eto/ins and viruses- protects fetus

and new!orn

Half0life 23 days



I"'Anti!odies

$entamer

401)* of serum

anti!odies

5i/ complement

In !lood+ lymph+ and on

6 cells

A""lutinates micro!es-

first A! produced in

response to infection

Half0life 4 days



I"AAnti!odies

Dimer 1)014* of serum

anti!odies

In secretions

'ucosal protection

Half0life days



I",Anti!odies

'onomer )8))2* of serum

anti!odies

On mast cells+!asophils+ and in !lood

Aller"ic reactions- lysis

of parasitic worms

6a!f%!ife 2 days

'onomer

)82* of serum

anti!odies

In !lood+ lymph+ and on

6 cells

On 6 cells+ initiate

immune response

6a!f%!ife 7 days

I"DAnti!odies



6 cells and Humoral Immunity

Effective against free antigen *to"ins, bacteria!

surface structures, viruses in between ce!!s

+ ce!! receptors *ost!y Ig8 and IgD

(ctivated +%ce!!s go through c!ona! e"pansion!eading to

18$lasma cells*effector ce!! for

antibody production and

28'emory cells


14/33

Clonal Selection

Fig 17.5

(#I8($I9# 6uora! Iunity' C!ona! e!ection and E"pansion
http://humoral_clonal.html/



9esponse to % dependentanti"ens

+ ce!!s re:uire he!p of $ ce!!s for ost proteinantigens (T-dependent ag)

+ ce!!s interna!i/e antigen and present it to $%he!per ce!! in cobination with 'HC class II

o!ecu!es

If $ ce!! recogni/es antigen itactivates + ce!! c!ona! e"pansion

p!asa ce!!s and eory ce!!s

Review

Fig 17.4


16/33

Anti"en$resentation !y60cell

Compare to Fig. 17.4



9esponse to % IndependentAnti"ens

&o %0helper cells involved

$olysaccharides ;!acterial capsules< and L$S

=ea> response

with no memory

cells?oun" children

react poorly

Fig 17.6


18/33


Anti!ody Diversity

101;different +%ce!! receptors

6ow any genes in huan genoe

Documents

M T Ch17 AdaptiveImmunity s