Table 2.

Immunity to B. pertussis infection and vaccines in humans

Immune responses to:	Humoral responses		T-cell responses
	Antibody (Ab) levels	Memory B cells	Th	Memory T cell
Natural infections	Levels and avidity index of anti-PT antibodies is higher in infected individuals compared to pertussis (wP/aP)- vaccinated individuals (Barkoff et al. 2012); Abs recognizing protective PT epitopes better elicited by natural infections compared to aP (Sutherland et al. 2011)	Pertussis-specific IgG levels and memory B cells decrease with time postinfection (9 mo); overall weak correlation between circulating pertussis IgG response and memory B cell frequency; PT responses decline faster than FHA and PRN ones; higher numbers of pertussis memory B cells in older (adult and elderly) compared to younger age (4 yr and preschool) in the acute phase (van Twillert et al. 2014); lower memory B cells and Abs responses in infants undergoing recurrent episodes of acute otitis media (Basha and Pichichero 2015)	Lower magnitude of PT-specific T-cell responses in naturally infected children (8–59 mo) compared to aP-vaccinated kids (Ausiello et al. 2000); Th1/Th17 responses are elicited (Mascart et al. 2003; Schure et al. 2012a)
Whole-cell pertussis vaccines	Lower Abs levels and avidity with wP compared with aP at 4 yr of age after primary series; preschool booster induces stronger responses in wP primed (Schure et al. 2013); avidity of Ab levels upon aP boost can be increased similarly in wP-primed and aP-primed adolescents (Prelog et al. 2013)	Lower frequency of memory B cells compared to aP (4 yr of age) after primary series; preschool booster induce stronger memory B-cell responses in wP primed (Schure et al. 2013)	Lower IFN-γ secreting T cells when compared to aP primary series (4 yr of age); preschool booster induces stronger Th responses in wP primed (Schure et al. 2013)	Better preschool boostability in wP-primed versus aP-primed individuals at 4 yr of age (Schure et al. 2012b)
Acellular pertussis	Th2 skewing (IgG4) after primary aP series in infants (Hendrikx et al. 2011c) and in adolescents (Jahnmatz et al. 2014b); lower avidity of PT-specific Ab responses when compared to those upon natural infections (Barkoff et al. 2012)	80% of aP-primed infants still show circulating memory B cells after primary series (Carollo et al. 2014); aP booster vaccine improve B-cell memory immunity (> wP) in 4-yr-old children in some cases but it wanes gradually (Hendrikx et al. 2011a)	aP booster vaccines improve T-cell (helper and memory) immunity (> wP) in 4-yr-old and 9-yr-old children (Schure et al. 2012b); Th1 in adolescents upon booster aP series, irrespective of wP or aP primary series (Rieber et al. 2011); overall, aP induces a more Th2 or balanced Th1/Th2 profile (Ausiello et al. 1997; Ryan et al. 1998; White et al. 2010); Th1 responses impaired upon vaccination during pregnancy (Huygen et al. 2015); T-cell immunodominance patterns are similar for wP and aP; the respective Th1 and Th2 skewing of wP and aP are unchanged for decades with aP boosters (Bancroft et al. 2016)	As good CD4 and CD8 T cells priming between aP and wP, there is a limited effect of a fifth aP dose in preschool children (de Rond et al. 2015); level of functionality (cytokine production) is weaker in aP-vaccinated preadolescents (Smits et al. 2013); 10 years post–last booster, T-cell responses still detectable even after Abs have decayed (Grondahl-Yli-Hannuksela et al. 2016)