Unprovoked Submassive Saddle Pulmonary Embolism in an Adult Male After Pfizer COVID-19 Vaccination.

Pulmonary emboli (PEs) occur when the pulmonary artery is blocked by foreign material. In one such instance, this foreign material can be a blood clot that may occur from patient risk factors inducing a prothrombotic state. The relationship between COVID-19 vaccines and a prothrombotic state is novel and changing as our understanding of the relationship between the two evolves. The patient in this case study presented with unrelenting and progressive dyspnea, tachycardia, and unilateral lower extremity swelling two days after receiving the second dose of the Pfizer COVID-19 vaccine. After diagnostic testing, the patient was found to have a submassive saddle pulmonary embolism with subsequent right heart strain. This patient was treated with appropriate anticoagulation therapies, including heparin and apixaban, as well as thrombectomy, and made a complete recovery. The possible relationship between COVID-19 vaccines and thrombotic events supports the need for increased awareness of a potential new risk factor behind the development of PE. It is our hope that this case report will help raise awareness of an association despite the lack of incident data at this time.

Unique glandular ex-vivo Th1 and Th17 receptor motifs in Sjögren's syndrome patients using single-cell analysis.

Primary Sjögren's syndrome (pSS) is an autoimmune disease in which the underlying cause has yet to be elucidated. The main objective of this study was to determine the T cell receptor (TCR) repertoires of individual infiltrating T helper (Th)-1 and 17 cells of pSS patients using single-cell analysis. Single-cell analysis of ex-vivo infiltrating T cells demonstrated that pSS patients had higher frequencies of activated Th17 cells. Single-cell TCR sequencing revealed that TCRß variable (TRBV)3-1/joint (J)1-2 (CLFLSMSACVW) and TRBV20-1/J1-1 (SVGSTAIPP*T) were expressed by activated Th1 and Th17 cells in both cohorts. Uniquely, TCRα variable (TRAV)8-2/J5 (VVSDTVLETAGE) was expressed by Th1 cells present only in patients and complementarity-determining region (CDR)3α-specific motif (LSTD*E) present in both Th1/Th17 cells. The study demonstrates that both activated Th1 and Th17 cells of pSS patients showed restricted clonal diversities of which two CDR3 motifs were present in controls and patients, with another two motifs unique to pSS.