Figure 7. B cell deficiency results in a significant reduction in cellular infiltration around vessel and bronchiole, hyperplasia of the bronchial epithelium and fibrosis.
B6.129S2-Igh-6tm1Cgn/J (B cell KO), control C57BL/6 (wild type), and B cell KO mice with passive transfer of 2.5×106 B cells were treated with either anti-MHC class I (anti-H2kb), isotype (C1.184) or nonspecific anti-MHC class I (anti H2kd) Abs on day 1, 2, 3, 6 and weekly thereafter (5 mice in each group). The lungs were harvested on day 30. Formalin preserved tissues were sectioned randomly and analyzed by H&E (a – e) and Masson's trichrome staining (d – i). Images were captured and representative area depicted in the figure. At least 4 out of 5 mice from each group demonstrated similar lesions in various sections of the lung. None of the B cell KO mice treated with anti-H2kb (b, g) demonstrated any significant fibrosis or airway obliteration, with minimal cellular infiltration and epithelial hyperplasia compared to wild type mice treated with anti-H2kd (c, h). B cell KO mice with passive transfer of B cells (e, j) demonstrated lesions similar to wild type mice. Wild type mice treated with non-specific anti-MHC class I (anti H2kd) (d, i) demonstrated no lesions. a,f: B cell KO with isotype control Abs; b,g: B cell KO with anti H2kb; c,h: wild type with anti-H2kb; d,i: wild type with anti-H2kd (non specific anti-MHC); e,j: B cell KO with passive transfer of B cells. B: bronchiole and V: vessels. Blue staining in trichrome stains denotes collagen deposition in the lungs.