TAS2R43 and obesity due to melanocortin 4 receptor deficiency: Double immunofluorescence staining of primary jejunal crypt cultures from patients with obesity showed that the bitter taste receptor TAS2R43 colocalized with α-defensin 5+ cells, a marker for Paneth cells (Figure 1A), and with mucin 2+ cells, a marker for goblet cells (Figure 1B).