CD4 and neoplasm: Subcutaneous synergic mouse tumour model with intra-tumoural OV injection:Survival: prolonged survival (IgG significant; scFV not significant) compared to parental OV and untreatedDisease control: significantly decreased tumour growth compared to parental OV and untreatedImmune response: IgG-OV significantly increased tumour infiltration of CD4+ and CD8+ T cells, the proportion of activated CD8+ T cells, and the CD8+/Foxp3+ T cell ratio compared to systemic anti-PD-L1 treatment, but to a lesser extent than parental OV alone