The discovery of broadly neutralizing antibodies (bNAbs) that target conserved epitopes on the HIV-1 envelope glycoprotein (Env) has garnered significant attention for its potential in the development of effective therapeutic and vaccine strategies. In this study, we isolated and characterized a CD4 binding site (CD4bs) antibody, FD22, from an elite neutralizer in China who had been infected with a clade B virus through contaminated blood plasma for 23 years. The heavy chain of FD22 was derived from a rarely reported IGHV3-30 germline gene and exhibited an exceptionally high degree of somatic hypermutation (SHM) (37%), along with a long and unique CDRH3 loop of 20-amino acids. FD22 exhibited potent and broad neutralizing activity, comparable to that of the well-known bNAb VRC01. It effectively neutralized 82% of a panel of 145 diverse HIV-1 pseudoviruses, including the two major circulating strains in China, CRF01_AE and CRF07_BC. FD22 bound strongly to HIV-1-infected cell lines, efficiently engaged FcγRIIIa receptors, triggered NK cell degranulation and the release of key cytokines such as IFN-γ and β-chemokines, and robustly induced antibody-dependent cellular cytotoxicity (ADCC) against HIV-1-infected target cells. Structural prediction for FD22 and the HIV Env SOSIP trimer performed by AlphaFold3, site-mutagenesis, and autologous virus reverse mutation assays revealed that the epitope of FD22 spans key CD4 binding site, including Loop D, the CD4 binding loop (CD4 BLP), and the V5 Loop. The unique long CDRH3 loop of FD22 interacts with the CD4 binding site through its negatively charged residue R102, distinguishing it from other CD4bs antibodies. Our findings provide valuable insights into the mechanisms of FD22 in viral neutralization and ADCC. The dual functionality of FD22 enhances its potential as a promising therapeutic antibody and offers new avenues for designing CD4bs-targeting vaccines with enhanced ADCC capabilities.
© 2025. The Author(s).

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related mortality, necessitating the exploration of alternate therapeutic approaches. Tumor-reactive or activated-by-cytokine killers (TRACK) are PD-L1+, highly cytolytic NK cells derived from umbilical cord blood NK cells and engineered to express soluble IL-15 (sIL15), and these cells show promise in preclinical studies against NSCLC.
We assessed safety, persistence, homing, and cytotoxic activity in 6 patients with advanced, refractory, and progressing NSCLC who received a low dose of unmatched, allogeneic, off-the-shelf sIL15_TRACK NK cells. We evaluated NK cell presence and persistence with droplet digital PCR (ddPCR), flow cytometry, and immunofluorescence staining.
sIL15_TRACK NK cells had peak measurements at 1 hour and became undetectable 4 hours after each infusion. Cognate ligands to activating NK cell receptors were found in NSCLC. sIL15_TRACK NK cells were observed in a lung tumor biopsy 7 days after the final infusion, confirming their sustainment and tumor-homing ability. They retained cytolytic function following isolation from the lung tumor. Three of 6 patients achieved disease stabilization on repeat imaging, while the others progressed.
Unmatched, allogeneic, cryopreserved, off-the-shelf sIL15_TRACK NK cells express activating receptors, home to tumor sites that express their cognate ligands, and retain cytolytic activity after infusion, underscoring their potential as a therapeutic approach in solid tumors. At low doses, the therapy was safely administered and showed preliminary evidence of activity in 3 of 6 patients with advanced and progressive NSCLC. Additional dose escalation cohorts and coadministration with atezolizumab are planned.

gov NCT05334329.
Funding was provided by CytoImmune Therapeutics and grants from the National Cancer Institute (CA266457, CA033572, and CA210087).

Hemoglobin-based oxygen carriers have been developed to compensate the needs of blood for transfusions. Most of them were based on intracellular hemoglobin extracted from bovine or human blood, but unfortunately, this type of hemoglobin did not pass through the last steps of clinical trials. In this context, HEMARINA discovered a natural extracellular hemoglobin, possessing several advantages avoiding intracellular hemoglobin-related side effects. Many preclinical studies assessed the safety of M101 used in intravenous (IV) injection in rodents. To explore the safety of IV injections of M101 in large mammals, six dogs received each a single injection of liquid M101 according to a dose escalation with a 48 h follow-up. Then, two monkeys received multiple IV injections of the same dose of M101 every hour for seven hours. This study showed that single and multiple IV injections in dogs and monkeys did not cause clinical or histological lesions, nor did they induce immunological reactions. This makes M101 the best candidate to date for human use in emergency situations requiring blood and, in several diseases, causing hypoxia problems.

The risk of severe disease caused by co-infection with SARS-CoV-2 and influenza virus (IAV) raises an annual concern for global public health. Extracellular vesicles (EV) derived from mesenchymal stem cells (MSC) possess anti-inflammatory properties that can attenuate the inflammatory cytokine levels induced by viral infection. However, the effects of MSC-EV treatment on SARS-CoV-2 and IAV co-infection have not been elucidated. In the present study, we co-induced lung epithelial cells (EpiC) with SARS-CoV-2 Spike protein (S) and H1N1 influenza viral HA protein (HA) and found robust upregulation of inflammatory cytokines in comparison to those induced by either S or HA protein. Consequently, treatment of lung endothelial cells (EC) with conditioned medium from EpiC co-induced by both S and HA proteins resulted in increased apoptosis and impaired angiogenic ability, suggesting the effects of co-induction on epithelial-endothelial crosstalk. In addition, lung EpiC co-induced by both S and HA proteins showed paracrine effects on the recruitment of immune cells, including monocytes, macrophages and neutrophils. Of Note, EV derived from Wharton Jelly's MSC (WJ-EV) transferred miR-146a to recipient lung EpiC, which impaired TRAF6 and IRAK1, resulting in the downregulation of NF-κB pathway and secretion of inflammatory cytokines, rescuing the epithelial-endothelial crosstalk, and reducing the elevation of immune cell recruitment. Moreover, the anti-inflammatory properties of WJ-EV are affected by type 2 Diabetes Mellitus. WJ-EV derived from donors with type 2 Diabetes Mellitus contained less miR-146a and showed impaired ability to downregulate the NF-κB pathway and inflammatory cytokines in recipient cells. Taken together, our findings demonstrate the role of miR-146a in targeting the NF-κB pathway in the anti-inflammatory abilities of WJ-EV, which is a promising strategy to rescue the epithelial-endothelial crosstalk altered by co-infection with SARS-CoV-2 and IAV.
© 2024. The Author(s).

Type 2 innate lymphoid cells (ILC2s) are crucial in regulating immune responses and various physiological processes, including tissue repair, metabolic homeostasis, inflammation, and cancer surveillance. Here, we present a protocol that outlines the isolation, expansion, and adoptive transfer of human ILC2s from peripheral blood mononuclear cells for an in vivo lineage tracking experiment in a mouse model. Additionally, we detail the steps involved in the adoptive transfer of human ILC2s to recipient mice bearing human liquid or solid tumors. For complete details on the use and execution of this protocol, please refer to Li et al.1.
Copyright © 2024. Published by Elsevier Inc.