CD8A and obesity due to melanocortin 4 receptor deficiency: This is achieved by inducing glucose intolerance, subsequently resulting in increased fat mass and body weight, hence modelling obesity and metabolic dysfunction (Figure 6B,C), with apparent sex effects in observed pathologies of HFD‐fed mice (Figure S5), giving importance to the continued inclusion of sex‐stratification in ongoing and future studies of systemic CD8 T cell dysfunction.