Salivette plain cotton swabs

Blood samples were collected in citrate tubes and centrifuged at 1,000 g for 10 min followed by 2,500 g for 10 min. Plasma aliquots were stored at −20°C.
For saliva collection between 8 and 12 a.m., patients were asked not to eat, drink or perform dental hygiene for at least 1 h before collection. Saliva was collected using Salivette^® plain cotton swabs (51.1534, Sarstedt, Nümbrecht, Germany) and kept on ice during the collection procedure. Swabs were centrifuged at 1,000 g for 2 min and saliva aliquots were stored at −80°C.
Supplementary Table S1 provides the clinicopathological characteristics of patients included in this study.

Saliva samples were obtained from newly diagnosed, treatment-naïve HNSCC patients with histologically confirmed tumors seen at the ENT department of Ulm University Hospital as well as from healthy donors (HD) in agreement with the local ethics committee (Votum #90/15). Each patient provided informed consent. The lab examiners were not blinded to the source of the material analyzed. Tables 1, 2 show clinicopathological data of enrolled patients.
Saliva was collected using Salivette^® plain cotton swabs (Sarstedt, Nürmbrecht, Germany, 51.1534) between 07:00 and 10:00 a.m. Patients did not eat, drink or perform dental hygiene for at least 1 h before collection to reduce contamination. The probands sequentially chewed six swabs for 1 min until they were soaked with saliva. Samples were immediately put on ice during the collection process. The swabs were centrifuged at 1,000 × g for 2 min to gather the saliva in the reservoir. The obtained saliva of each sample was pooled to ensure a homogenous mix for each patient. The resulting saliva specimens were stored in aliquots at −80°C until further use.