The effects of signal transducer and activator of transcription three mutations on human platelets

Figures & data

Table I. Patient characteristics.

Cohorts	STAT3 loss-of-function cohort		SNP cohort
	AD-HIES	Control subjects	Healthy individuals
Number (n)	8	10	483
Age (mean, SD)	38 ± 10.5	32 ± 9.2	28.5 ± 13.7
Gender (% male)	37.5	40	44.3
Mutation domain (n)		N/A	N/A
DNA-binding domain	5
SH2 domain	2
Linker-domain	1
SNP frequency*	N/A	N/A
rs744166			31.5/48.4/20.1%
rs3816769			58.6/37.0/4.4%
rs4796793			37.7/48.9/13.4%
Medication	Antifungal therapy, prophylactic antibiotic treatment	No medication	No medication
Clinical complications	Recurrent RTIs, eczema, “cold abscesses”	None	None

Characteristics of the two study cohorts. AD-HIES: Autosomal-dominant hyper IgE syndrome; N/A: not applicable; RTI: respiratory tract infection; SH2: Src Homology 2; SNP: single nucleotide polymorphism. *Homozygous for common allele/heterozygous/homozygous for rare allele.

Table II. STAT3 loss-of-function mutations.

Protein domain	Site of mutation	DNA sequence change	Predicted amino acid change	Number of patients
DNA-binding	Exon 13	1144C → T	R382W	2* ^(1)
	Exon 13	1145G → A	R382Q	1
	Exon 16	1387 deletion GTG	V463 deletion	1
	Intron 11	1110-2A → G	G380 deletion	1*
SH2	Exon 21	1909C → G	V637L	1
	Exon 21	1909G → A	V637M	1*
Linker domain	Exon 19	1679-1681 deletion	S560 deletion	1*

Specification of the STAT3 loss-of-function mutations. DNA: Deoxyribonucleid acid; SH2: Src Homology 2. Patients indicated with an asterisk (*) were functionally assessed. (1): one of the 2 patients was functionally assessed.

Figure 1. Functional assessment of GPVI-mediated platelet activation in STAT3 loss-of-function patients.

(A) Platelet P-selectin expression in unstimulated samples (median MFI 3.03 (IQR 2.62–3.84) in STAT3 loss-of-function versus 4.82 (IQR 3.53–5.67) in control subjects, p = 0.01). (B) Platelet P-selectin expression in GPVI-mediated platelet activation by CRP stimulation (p < 0.001). (C) Platelet P-selectin expression in PAR-1-mediated platelet activation by TRAP (p = 0.054). (D) P-selectin expression in GPVI-mediated platelet activation by CRP after blockade of the ADP pathway by apyrase. Data are presented as median with IQR (ADP: adenosine 5′ diphosphate; CRP: collagen-related peptide; GPVI: glycoprotein VI; MFI: mean fluorescence intensity; TRAP: thrombin receptor-activating peptide-6).

Figure 2. SNPs rs744166, rs3816769, and rs4796793 and P-selectin expression (AUC).

SNP characteristics are shown in the upper figure. P-selectin expression (AUC of MFI) after GPVI-mediated platelet activation by seven concentrations of CRP is shown in the lower figure. Data are presented as median with IQR (AUC: Area under the curve; CRP: collagen-related peptide, GPVI: glycoprotein VI; IQR: interquartile range; MAF: minor allele frequency; MFI: mean fluorescence intensity; SNP: single nucleotide polymorphism).

Table III. Median platelet numbers (range).

STAT3 loss-of-function cohort	Highest (platelets × 10^9/l)	Lowest (platelets × 10^9/l)
♀, 46 years	264	229
♀, 46 years*	247	160
♀, 23 years*	505	231
♂, 47 years*	317	168
♂, 26 years	242	133
♀, 34 years	314	205
♀, 32 years*	431	175
♀, 50 years	257	206
SNP cohort	Wild type	Heterozygous	Homozygous for SNP
rs744166	274 (132–470)	257 (132–491)	268 (133–488)
rs3816769	276 (132–470)	263 (132–491)	266 (133–488)
rs4796793	280 (159–401)	275 (132–491)	261 (132–488)

Platelet numbers from STAT3 loss-of-function patients, platelets × 10⁹/l, and platelet numbers from the SNP cohort, median platelet numbers × 10⁹/l (range). Patients indicated with an asterisk (*) were functionally assessed. ♀: Female; ♂: male; SNP: single nucleotide polymorphism.

Figure 3. TPO and IL-6 levels in plasma.

(A) Plasma TPO levels in STAT3 loss-of-function patients and control subjects. (B) Plasma IL-6 expression in STAT3 loss-of-function patients and control subjects (IL-6: Interleukin-6; TPO: thrombopoietin).