Dynamic changes in the systemic immune responses of spinal cord injury model mice

Intraspinal inflammatory and immune responses are considered to play central roles in the pathological development of spinal cord injury.This study aimed to decipher the dynamics of systemic immune responses,initiated by spinal cord injury.The spinal cord in mice was completely transected at T8.Changes in the in vivo inflammatory response,between the acute and subacute stages,were observed.A rapid decrease in C-reactive protein levels,circulating leukocytes and lymphocytes,spleen-derived CD4~+interferon-γ+T-helper cells,and inflammatory cytokines,and a marked increase in neutrophils,monocytes,and CD4~+CD25~+FOXP3~+regulatory T-cells were observed during the acute phase.These systemic immune alterations were gradually restored to basal levels during the sub-acute phase.During the acute phase of spinal cord injury,systemic immune cells and factors showed significant inhibition;however,this inhibition was transient,and the indicators of these serious disorders gradually returned to baseline levels during the subacute phase.All experiments were performed in accordance with the institutional animal care guidelines,approved by the Institutional Animal Care and Use Committee of Experimental Animal Center of Drum Tower Hospital,China(approval No.2019 AE01040)on June 25,2019.

Photosynthetic microorganisms coupled photodynamic therapy for enhanced antitumor immune effect

The ideal photodynamic therapy(PDT)should effectively remove the primary tumor,and produce a stronger immune memory effect to inhibit the tumor recurrence and tumor metastasis.However,limited by the hypoxic and immunosuppressive microenvironment,the PDT efficiency is apparently low.Here,Chlorella(Chl.)is exploited to enhance local effect by producing oxygen to reverse hypoxia,and release adjuvants to reverse immunosuppressive microenvironment to enhance abscopal effect afterwards.Results from different animal models indicated that Chl.could enhance local effect and PDT related immune response.Ultimately,Chl.coupled PDT elicited anti-tumor effects toward established primary tumors(inhibition rate:90%)and abscopal tumors(75%),controlled the challenged tumors(100%)and alleviated metastatic tumors(90%).This Chl.coupled PDT strategy can also produce a stronger anti-tumor immune memory effect.Overall,this Chl.coupled PDT strategy generates enhanced local tumor killing,boosts PDT-induced immune responses and promotes anti-tumor immune memory effect,which may be a great progress for realizing systemic effect of PDT.