Erythrocyte lysate

We obtained samples by isolating total blood mononuclear cells from whole blood samples (about 2 mL) taken from each participant’s stored specimens using the erythrocyte lysate (Sango Biotech, Shanghai, China) according to the manufacturer's instructions. We extracted total DNA with a DNA extraction kit (Generay Biotech, Shanghai, China). Three SNPs (rs2305619, rs3816527, and rs1840680) of PTX3 were candidates based on their associations and functional consequences with pulmonary infectious diseases in previous studies.^{24 (link),28 (link)–30 (link, link)} We conducted real-time polymerase chain reaction (qPCR) in triplicate using the TaKaRa Premix Ex Taq II Kit (TaKaRa Bio Inc., Dalian, China) according to the manufacturer’s instructions. A melting curve analysis according to the fluorescent color of the probes was used to define the genotyping of the SNPs, which was analyzed with CFX Manager software 1.6 (Bio-Rad, Hercules, CA, USA).

In line with previous studies (18 (link)-20 (link),23 (link)), three SNPs (rs2305619, rs3816527, and rs1840680) of PTX3 were selected. The genotypes are shown in Table 2.
Peripheral blood obtained from each subject was isolated by erythrocyte lysate (Sango Biotech, Shanghai, China) according to the manufacturer’s instructions. Genomic DNA was extracted using a genomic DNA extraction kit (Shanghai Generay Biotech, China).