Table 1. Summary of results of included in vitro and clinical studies.

HS: hyperacute serum, MSCs: mesenchymal stem cells, PRP: platelet-rich plasma, FCS: fetal calf serum, EPRP: PRP prepared in the presence of EDTA, CPRP: PRP prepared in the presence of citrate, AD-MSCs: adipose-derived MSCs, 3D: three dimensional, IFP: infrapatellar fat pad, EVs: extracellular vesicles, VAS: visual analogue scale, KOOS: knee injury and osteoarthritis outcome score

Author	Reference	Study type	Main findings
Simon et al.	[11]	In vitro	Supplementation with HS led to significantly higher viability of MSCs, and bone and marrow explants along with higher integrity of bone marrow. In addition, it also led to significantly higher viability of osteoarthritic chondrocytes compared to PRP and FCS.
Kardos et al.	[12]	In vitro	Supplementation with HS led to significantly higher cell viability of cartilage, bone, and synovial membrane. It also led to a significant decrease in the expression of pro-inflammatory cytokines and an increase in the expression of anti-inflammatory cytokines.
Neubauer et al.	[13]	In vitro	Supplementation with HS led to significantly higher viability of AD-MSCs isolated from 3 different tissue types compared to EPRP and FCS. It also led to enhanced differentiation towards both osteogenic and chondrogenic lineages, unlike EPRP and CPRP which showed varied outcomes in terms of concentration used and differentiation towards specific lineage.
Otahal et al.	[14]	In vitro	EVs isolated from HS led to significantly higher expression of chondrogenic-lineage specific collagen type II and reduced expression of pro-inflammatory cytokines.
Kuten-Pella et al.	[15]	In vitro	Supplementation with HS led to significantly higher expression of chondrogenic-related genes in a 3D osteoarthritic chondrocyte pellet model.
Calvo et al.	[16]	In vitro	Supplementation with lyophilized HS led to a significantly higher rate of cell proliferation, similar to that of freshly prepared HS. In addition, it led to a significant reduction in the expression levels of pro-inflammatory cytokines.
Neubauer et al.	[17]	In vitro	Supplementation with HS led to the significantly higher metabolic activity of AD-MSCs isolated from the IFP. It also led to a significant increase in the expression of chondrogenic-lineage-specific genes.
Calvo et al.	[18]	Clinical	Intra-articular administration of 3 mL autologous HS (three times on a weekly basis) led to significant improvements in pain measured via VAS, and mobility/function measured via KOOS and Lysholm-Tegner score at six months follow-up compared to the baseline.