Indirect immunofluorescence detection of xyloglucan and pectic HG epitopes in TS pea stem internode. a. Bright field image showing anatomy. b. Calcofluor White image of section shown in a showing all cell walls. c. LM15 binding to an equivalent section. The antibody binds most strongly to distal region of protoxylem (arrowheads). d. An equivalent section to c that had been pre-treated with pectate lyase to remove pectic HG. LM15 binds strongly to epidermal and parenchyma cell walls. e. Section immunolabelled with pectic HG probe JIM5. f. Equivalent section to e pre-treated with pectate lyase indicates that the JIM5 epitope had been abolished. Arrows indicate inner edge of pith parenchyma. Dotted shaft arrows indicate junction between non-sclerifed parenchyma cell walls with sclerified parenchyma/fibre cell walls. cp = cortical parenchyma, pp = pith parenchyma, ep = epidermis, vb = vascular bundle, pf = phloem fibre bundle. Scale = 100 μm.