Antibodies to MHC class II molecules induce autoimmunity: critical role for macrophages in the immunopathogenesis of obliterative airway disease

Immunoinformatics study to search epitopes of spike glycoprotein from SARS-CoV-2 as potential vaccine

The Coronavirus disease named COVID-19 is caused by the virus reported in 2019 first identified in China. The cases of this disease have increased and as of June 1st, 2020 there are more than 216 countries affected. Pharmacological treatments have been proposed based on the resemblance of the HIV virus. With regard to prevention there is no vaccine, thus, we proposed to explore the spike protein due to its presence on the viral surface, and it also contains the putative viral entry receptor as well as the fusion peptide (important in the genome release). In this work we have employed In Silico techniques such as immunoinformatics tools which permit the identification of potential immunogenic regions on the viral surface (spike glycoprotein). From these analyses, we identified four epitopes E332-370, E627-651, E440-464 and E694-715 that accomplish essential features such as promiscuity, conservation grade, exposure and universality, and they also form stable complexes with MHCII molecule. We suggest that these epitopes could generate a specific immune response, and thus, they could be used for future applications such as the design of new epitope vaccines against the SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

Regulatory T Cell Transmigration and Intravascular Migration Undergo Mechanistically Distinct Regulation at Different Phases of the Inflammatory Response

Regulatory T cells (Tregs) play important roles in limiting inflammatory responses in the periphery. During these responses, Treg abundance in affected organs increases and interfering with their recruitment results in exacerbation of inflammation. However, the mechanisms whereby Tregs enter the skin remain poorly understood. The aim of this study was to use intravital microscopy to investigate adhesion and transmigration of Tregs in the dermal microvasculature in a two-challenge model of contact sensitivity. Using intravital confocal microscopy of Foxp3-GFP mice, we visualized endogenous Tregs and assessed their interactions in the dermal microvasculature. Four hours after hapten challenge, Tregs underwent adhesion with ∼25% of these cells proceeding to transmigration, a process dependent on CCR4. At 24 h, Tregs adhered but no longer underwent transmigration, instead remaining in prolonged contact with the endothelium, migrating over the endothelial surface. Four hours after a second challenge, Treg transmigration was restored, although in this case transmigration was CCR4 independent, instead involving the CCR6/CCL20 pathway. Notably, at 24 h but not 4 h after challenge, endothelial cells expressed MHC class II (MHC II). Moreover, at this time of peak MHC II expression, inhibition of MHC II reduced Treg adhesion, demonstrating an unexpected role for MHC II in Treg attachment to the endothelium. Together these data show that Treg adhesion and transmigration can be driven by different molecular mechanisms at different stages of an Ag-driven inflammatory response. In addition, Tregs can undergo prolonged migration on the inflamed endothelium.

A dendritic cell-based systemic vaccine induces long-lived lung-resident memory Th17 cells and ameliorates pulmonary mycosis

Tissue-resident memory T cells (TRMs) are a novel nonvascular memory T cell subset. Although CD8⁺ TRMs are well-characterized, CD4⁺ TRMs-especially lung-resident memory Th17 cells-are still being defined. In this study, we characterized lung-resident memory Th17 cells (lung TRM17) and their role in protection against the highly virulent fungus Cryptococcus gattii. We found that intravenously transferred DCs preferentially migrated to lungs and attracted recipient DCs and led to the induction of long-lived Th17 cells expressing characteristic markers. This population could be clearly discriminated from circulating T cells by intravascular staining and was not depleted by the immunosuppressive agent FTY720. The C. gattii antigen re-stimulation assay revealed that vaccine-induced lung Th17 cells produced IL-17A but not IFNγ. The DC vaccine significantly increased IL-17A production and suppressed fungal burden in the lungs and improved the survival of mice infected with C. gattii. This protective effect was significantly reduced in the IL-17A knockout (KO) mice, but not in the FTY720-treated mice. The protective effect also coincided with the activation of neutrophils and multinucleated giant cells, and these inflammatory responses were suppressed in the vaccinated IL-17A KO mice. Overall, these data demonstrated that the systemic DC vaccine induced lung TRM17, which played a substantial role in anti-fungal immunity.

Attenuating Effects of Nortrachelogenin on IL-4 and IL-13 Induced Alternative Macrophage Activation and on Bleomycin-Induced Dermal Fibrosis

Excessive alternative macrophage activation contributes to fibrosis. We studied the effects of nortrachelogenin, the major lignan component of Pinus sylvestris knot extract, on alternative (M2) macrophage activation. J774 murine and THP-1 human macrophages were cultured with IL-4+IL-13 to induce alternative activation, together with the extract and its components. Effects of nortrachelogenin were also studied in bleomycin-induced murine dermal fibrosis model. Knot extract significantly decreased the expression of alternative activation markers-arginase 1 in murine macrophages (97.4 ± 1.3% inhibition at 30 μg/mL) and CCL13 and PDGF in human macrophages-as did nortrachelogenin (94.9 ± 2.4% inhibition of arginase 1 at 10 μM). Nortrachelogenin also decreased PPARγ expression but had no effect on STAT6 phosphorylation. In vivo, nortrachelogenin reduced bleomycin-induced increase in skin thickness as well as the expression of collagens COL1A1, COL1A2, and COL3A1 (all by >50%). In conclusion, nortrachelogenin suppressed IL-4+IL-13-induced alternative macrophage activation and ameliorated bleomycin-induced fibrosis, indicating therapeutic potential in fibrosing conditions.

Bronchus-associated lymphoid tissue-resident Foxp3+ T lymphocytes prevent antibody-mediated lung rejection

Antibody-mediated rejection (AMR) is a principal cause of acute and chronic failure of lung allografts. However, mechanisms mediating this oftentimes fatal complication are poorly understood. Here, we show that Foxp3+ T cells formed aggregates in rejection-free human lung grafts and accumulated within induced bronchus-associated lymphoid tissue (BALT) of tolerant mouse lungs. Using a retransplantation model, we show that selective depletion of graft-resident Foxp3+ T lymphocytes resulted in the generation of donor-specific antibodies (DSA) and AMR, which was associated with complement deposition and destruction of airway epithelium. AMR was dependent on graft infiltration by B and T cells. Depletion of graft-resident Foxp3+ T lymphocytes resulted in prolonged interactions between B and CD4+ T cells within transplanted lungs, which was dependent on CXCR5-CXCL13. Blockade of CXCL13 as well as inhibition of the CD40 ligand and the ICOS ligand suppressed DSA production and prevented AMR. Thus, we have shown that regulatory Foxp3+ T cells residing within BALT of tolerant pulmonary allografts function to suppress B cell activation, a finding that challenges the prevailing view that regulation of humoral responses occurs peripherally. As pulmonary AMR is largely refractory to current immunosuppression, our findings provide a platform for developing therapies that target local immune responses.

Targeting antigen presentation in autoimmunity

Autoimmune diseases are heterogeneous group of disorders that together represent an enormous societal and medical problem. CD4+ T cells have critical roles in the initiation and pathogenesis of autoimmune disease. As such, modulation of T cell activity has proven to have significant therapeutic effects in multiple autoimmune settings. T cell activation is a complex process with multiple potential therapeutic targets, many of which have been successfully utilized to treat human disease. Current pharmacological treatment largely targets T cell intrinsic activities as a means of treating various autoimmune disorders. Here I review extant and potential therapeutic approaches that instead specifically target antigen presentation to CD4+ T cells as a critical checkpoint in autoimmune responses. In addition, the contribution of antigen modulation components in current therapeutic approaches is considered along with the impact of new antigen targeted treatment modalities. Finally, potential challenges are considered in the context of the potential for antigen specific targeting of the antigen presentation process.

T Helper Cell Subsets in Experimental Lung Allograft Rejection

BACKGROUND

Human lung transplantation has evolved to an established treatment for pulmonary diseases in their end stages; however, the long-term outcome is worse when compared to all other solid transplantable organs. The major reason for this unfavorable outcome is rejection, either in its acute or chronic form, the latter termed as chronic lung allograft dysfunction.

METHODS

A systematic review search was performed.

RESULTS

One of the most important immune cells responsible for rejection are T cells. Beside alloreactive CD8+ T cells, CD4+ T cells play a key role during the evolvement of allograft rejection. Certain subsets of these allograft CD4+ T cells have been identified which have been shown to exert either transplant-protective or transplant-injuring properties. These effects have been proven in various experimental models, mainly in rats and mice, and allowed for the gain of important insights into these proinflammatory and anti-inflammatory characteristics including their targetability: while the subsets Th1, Th17, Th22, and Tfh cells have been shown to act in a rather proinflammatory way, Tregs, Th2, and Th9 subsets exert anti-inflammatory effects. Chronic airway obstruction is mainly induced by IL17 as shown across models.

CONCLUSIONS

This review shall summarize and provide an overview of the current evidence about the role and effects of proinflammatory and anti-inflammatory CD4-+ T helper cell subsets during lung allograft rejection in experimental rodent models.

Visualization of Monocytic Cells in Regressing Atherosclerotic Plaques by Intravital 2-Photon and Positron Emission Tomography-Based Imaging-Brief Report

OBJECTIVE

Aortic arch transplants have advanced our understanding of processes that contribute to progression and regression of atherosclerotic plaques. To characterize the dynamic behavior of monocytes and macrophages in atherosclerotic plaques over time, we developed a new model of cervical aortic arch transplantation in mice that is amenable to intravital imaging.

APPROACH AND RESULTS

Vascularized aortic arch grafts were transplanted heterotropically to the right carotid arteries of recipient mice using microsurgical suture techniques. To image immune cells in atherosclerotic lesions during regression, plaque-bearing aortic arch grafts from B6 ApoE-deficient donors were transplanted into syngeneic CX3CR1 GFP reporter mice. Grafts were evaluated histologically, and monocytic cells in atherosclerotic plaques in ApoE-deficient grafts were imaged intravitally by 2-photon microscopy in serial fashion. In complementary experiments, CCR2+ cells in plaques were serially imaged by positron emission tomography using specific molecular probes. Plaques in ApoE-deficient grafts underwent regression after transplantation into normolipidemic hosts. Intravital imaging revealed clusters of largely immotile CX3CR1+ monocytes/macrophages in regressing plaques that had been recruited from the periphery. We observed a progressive decrease in CX3CR1+ monocytic cells in regressing plaques and a decrease in CCR2+ positron emission tomography signal during 4 months.

CONCLUSIONS

Cervical transplantation of atherosclerotic mouse aortic arches represents a novel experimental tool to investigate cellular mechanisms that contribute to the remodeling of atherosclerotic plaques.

Zbtb7a induction in alveolar macrophages is implicated in anti-HLA-mediated lung allograft rejection

Chronic rejection significantly limits long-term success of solid organ transplantation. De novo donor-specific antibodies (DSAs) to mismatched donor human leukocyte antigen after human lung transplantation predispose lung grafts to chronic rejection. We sought to delineate mediators and mechanisms of DSA pathogenesis and to define early inflammatory events that trigger chronic rejection in lung transplant recipients and obliterative airway disease, a correlate of human chronic rejection, in mouse. Induction of transcription factor zinc finger and BTB domain containing protein 7a (Zbtb7a) was an early response critical in the DSA-induced chronic rejection. A cohort of human lung transplant recipients who developed DSA and chronic rejection demonstrated greater Zbtb7a expression long before clinical diagnosis of chronic rejection compared to nonrejecting lung transplant recipients with stable pulmonary function. Expression of DSA-induced Zbtb7a was restricted to alveolar macrophages (AMs), and selective disruption of Zbtb7a in AMs resulted in less bronchiolar occlusion, low immune responses to lung-restricted self-antigens, and high protection from chronic rejection in mice. Additionally, in an allogeneic cell transfer protocol, antigen presentation by AMs was Zbtb7a-dependent where AMs deficient in Zbtb7a failed to induce antibody and T cell responses. Collectively, we demonstrate that AMs play an essential role in antibody-induced pathogenesis of chronic rejection by regulating early inflammation and lung-restricted humoral and cellular autoimmunity.

Models of Lung Transplant Research: a consensus statement from the National Heart, Lung, and Blood Institute workshop

Lung transplantation, a cure for a number of end-stage lung diseases, continues to have the worst long-term outcomes when compared with other solid organ transplants. Preclinical modeling of the most common and serious lung transplantation complications are essential to better understand and mitigate the pathophysiological processes that lead to these complications. Various animal and in vitro models of lung transplant complications now exist and each of these models has unique strengths. However, significant issues, such as the required technical expertise as well as the robustness and clinical usefulness of these models, remain to be overcome or clarified. The National Heart, Lung, and Blood Institute (NHLBI) convened a workshop in March 2016 to review the state of preclinical science addressing the three most important complications of lung transplantation: primary graft dysfunction (PGD), acute rejection (AR), and chronic lung allograft dysfunction (CLAD). In addition, the participants of the workshop were tasked to make consensus recommendations on the best use of these complimentary models to close our knowledge gaps in PGD, AR, and CLAD. Their reviews and recommendations are summarized in this report. Furthermore, the participants outlined opportunities to collaborate and directions to accelerate research using these preclinical models.

Autologous and Allogenous Antibodies in Lung and Islet Cell Transplantation

The field of organ transplantation has undoubtedly made great strides in recent years. Despite the advances in donor-recipient histocompatibility testing, improvement in transplantation procedures, and development of aggressive immunosuppressive regimens, graft-directed immune responses still pose a major problem to the long-term success of organ transplantation. Elicitation of immune responses detected as antibodies to mismatched donor antigens (alloantibodies) and tissue-restricted self-antigens (autoantibodies) are two major risk factors for the development of graft rejection that ultimately lead to graft failure. In this review, we describe current understanding on genesis and pathogenesis of antibodies in two important clinical scenarios: lung transplantation and transplantation of islet of Langerhans. It is evident that when compared to any other clinical solid organ or cellular transplant, lung and islet transplants are more susceptible to rejection by combination of allo- and autoimmune responses.

Lung-Restricted Antibodies Mediate Primary Graft Dysfunction and Prevent Allotolerance after Murine Lung Transplantation

Over one-third of lung recipients have preexisting antibodies against lung-restricted antigens: collagen (Col) type V and K-α1 tubulin (KAT). Although clinical studies have shown association of these antibodies with primary graft dysfunction (PGD), their biological significance remains unclear. We tested whether preexisting lung-restricted antibodies can mediate PGD and prevent allotolerance. A murine syngeneic (C57BL/6) or allogeneic (C57BL/6 to BALB/c) left lung transplantation model was used. Rabbit polyclonal antibodies were produced against KAT and Col-V and injected pretransplantation. T cell frequency was analyzed using enzyme-linked immunospot, whereas alloantibodies were determined using flow cytometry. Wet:dry ratio, arterial oxygenation, and histology were used to determine PGD. Preexisting Col-V or KAT, but not isotype control, antibodies lead to dose-dependent development of PGD after syngeneic lung transplantation, as evidenced by poor oxygenation and increased wet:dry ratio. Histology confirmed alveolar and capillary edema. The native right lung remained unaffected. Epitope spreading was observed where KAT antibody treatment led to the development of IL-17-producing CD4⁺ T cells and humoral response against Col-V, or vice versa. In contrast, isotype control antibody failed to induce Col-V- or KAT-specific cellular or humoral immunity. In addition, none of the mice developed immunity against a non-lung antigen, collagen type II. Preexisting lung-restricted antibodies, but not isotype control, prevented development of allotolerance using the MHC-related 1 and cytotoxic T-lymphocyte-associated protein 4-Ig regimen. Lung-restricted antibodies can induce both early and delayed lung graft dysfunction. These antibodies can also cause spreading of lung-restricted immunity and promote alloimmunity. Antibody-directed therapy to treat preexisting lung-restricted antibodies might reduce PGD after lung transplantation.

Long-Term Persistence of Donor Alveolar Macrophages in Human Lung Transplant Recipients That Influences Donor-Specific Immune Responses

Steady-state alveolar macrophages (AMs) are long-lived lung-resident macrophages with sentinel function. Evidence suggests that AM precursors originate during embryogenesis and populate lungs without replenishment by circulating leukocytes. However, their presence and persistence are unclear following human lung transplantation (LTx). Our goal was to examine donor AM longevity and evaluate whether AMs of recipient origin seed the transplanted lungs. Origin of AMs was accessed using donor-recipient HLA mismatches. We demonstrate that 94-100% of AMs present in bronchoalveolar lavage (BAL) were donor derived and, importantly, AMs of recipient origin were not detected. Further, analysis of BAL cells up to 3.5 years post-LTx revealed that the majority of AMs (>87%) was donor derived. Elicitation of de novo donor-specific antibody (DSA) is a major post-LTx complication and a risk factor for development of chronic rejection. The donor AMs responded to anti-HLA framework antibody (Ab) with secretion of inflammatory cytokines. Further, in an experimental murine model, we demonstrate that adoptive transfer of allogeneic AMs stimulated humoral and cellular immune responses to alloantigen and lung-associated self-antigens and led to bronchiolar obstruction. Therefore, donor-derived AMs play an essential role in the DSA-induced inflammatory cascade leading to obliterative airway disease of the transplanted lungs.

Antibody-mediated rejection of the lung: A consensus report of the International Society for Heart and Lung Transplantation

Antibody-mediated rejection (AMR) is a recognized cause of allograft dysfunction in lung transplant recipients. Unlike AMR in other solid-organ transplant recipients, there are no standardized diagnostic criteria or an agreed-upon definition. Hence, a working group was created by the International Society for Heart and Lung Transplantation with the aim of determining criteria for pulmonary AMR and establishing a definition. Diagnostic criteria and a working consensus definition were established. Key diagnostic criteria include the presence of antibodies directed toward donor human leukocyte antigens and characteristic lung histology with or without evidence of complement 4d within the graft. Exclusion of other causes of allograft dysfunction increases confidence in the diagnosis but is not essential. Pulmonary AMR may be clinical (allograft dysfunction which can be asymptomatic) or sub-clinical (normal allograft function). This consensus definition will have clinical, therapeutic and research implications.

De novo-developed antibodies to donor MHC antigens lead to dysregulation of microRNAs and induction of MHC class II

Immune responses to HLA and development of anti-donor HLA (DSA) were shown to play a role in chronic rejection following transplantation. We hypothesized that Abs to MHC change microRNAs (miRNAs), leading to chronic lung allograft rejection. Microarray analysis was performed in a murine model of anti-MHC-induced obliterative airway disease (OAD), a correlate of obliterative bronchiolitis. A unique profile of dysregulated miRNAs was detected in OAD mice on days 7 and 15 after Ab administration compared with control. Sixty-seven miRNAs were increased and 42 miRNAs were decreased in OAD mice on day 7. In addition, 15 miRNAs were overexpressed and 16 miRNAs were underexpressed in OAD mice on day 15. The expression of miR-16 and miR-195 was significantly decreased in lungs of OAD mice, as assessed by quantitative RT-PCR and in situ hybridization, with increases in H-2 Aa and H-2 Dma mRNA levels. Significant reductions in miR-16 and miR-195 levels were also noted in lung transplant (LTx) patients with DSA compared with LTx patients without DSA. Bioinformatic TargetScan and reporter assays identified the binding of miR-16 and miR-195 to the 3'-untranslated region of regulatory factor X 5. Quantitative PCR and immunohistochemistry indicated posttranscriptional increases in regulatory factor X 5 mRNA and protein expression in OAD mice, as well as in LTx recipients with DSA, which was associated with increased expression of HLA-DPA1, HLA-DQA1, and HLA-DRA mRNA. Therefore, our results demonstrated that miRNAs induced by alloimmunity may play important roles in chronic rejection after LTx.

CYP2J2 attenuates metabolic dysfunction in diabetic mice by reducing hepatic inflammation via the PPARγ

Epoxyeicosatrienoic acids (EETs) and arachidonic acid-derived cytochrome P450 (CYP) epoxygenase metabolites have diverse biological effects, including anti-inflammatory properties in the vasculature. Increasing evidence suggests that inflammation in type 2 diabetes is a key component in the development of insulin resistance. In this study, we investigated whether CYP epoxygenase expression and exogenous EETs can attenuate insulin resistance in diabetic db/db mice and in cultured hepatic cells (HepG2). In vivo, CYP2J2 expression and the accompanying increase in EETs attenuated insulin resistance, as determined by plasma glucose levels, glucose tolerance test, insulin tolerance test, and hyperinsulinemic euglycemic clamp studies. CYP2J2 expression reduced the production of proinflammatory cytokines in liver, including CRP, IL-6, IL-1β, and TNFα, and decreased the infiltration of macrophages in liver. CYP2J2 expression also decreased activation of proinflammatory signaling cascades by decreasing NF-κB and MAPK activation in hepatocytes. Interestingly, CYP2J2 expression and exogenous EET treatment increased glucose uptake and activated the insulin-signaling cascade both in vivo and in vitro, suggesting that CYP2J2 metabolites play a role in glucose homeostasis. Furthermore, CYP2J2 expression upregulated PPARγ, which has been shown to induce adipogenesis, which attenuates dyslipidemias observed in diabetes. All of the findings suggest that CYP2J2 expression attenuates the diabetic phenotype and insulin resistance via inhibition of NF-κB and MAPK signaling pathways and activation of PPARγ.

Inducible costimulatory molecule deficiency induced imbalance of Treg and Th17/Th2 delays rejection reaction in mice undergoing allogeneic tracheal transplantation

OBJECTIVE

This study aimed to investigate the role of inducible costimulatory molecule (ICOS) pathway in the rejection reaction of mice undergoing allogeneic tracheal transplantation.

METHODS

The bronchus was separated from wide-type (WT) BalB/c mice and transplanted into WT BalB/c mice, C57 mice and icos(-/-) mice to prepare the obliterative bronchiolitis (OB) animal model. The transplanted bronchus was pathologically examined; flow cytometry was done to detect the T cell subsets and activity of the bronchus and spleen of recipient mice.

RESULTS

21 d after transplantation, evident rejection reaction was observed and the proportion of Th2 and Th17 cells increased significantly in the bronchus and spleen in C57 mice receiving allogeneic tracheal transplantation when compared with mice with autologous transplantation, but the proportion of Treg cells was comparable between them. When compared with WT BalB/c mice, the proportion of Th2, Th17 and Treg cells reduced markedly and rejection reaction was attenuated in icos(-/-) mice receiving tracheal transplantation, although rejection reaction was still noted.

CONCLUSION

icos knockout may delay the rejection reaction after tracheal transplantation, which might be ascribed to the imbalance among Th2, Th17 and Treg cells.

Comparison of four different allogeneic bone grafts for alveolar ridge reconstruction: a preliminary histologic and biochemical analysis

OBJECTIVES

Allograft material for alveolar ridge reconstruction is quite promising and appears to be as equally successful as bone autograft material. The aim of the present study was to compare four different allogeneic bone grafts in terms of their histologic structure and DNA content before grafting.

STUDY DESIGN

Four allograft specimens from different suppliers were analyzed histologically, and the DNA content was analyzed before clinical use of the allografts.

RESULTS

Organic tissue remnants were detected in all of the evaluated samples. In the present samples adipocytes, fibroblasts, osteocytes, and chondrocytes were identified and DNA isolation and purification was possible.

CONCLUSION

Demineralized freeze-dried allogeneic bone transplants can stimulate new bone formation and are a viable alternative to bone autograft material. However, the well-tolerated use of allograft material in regard to our findings should be further investigated.

Anti-major histocompatibility complex-induced obliterative airway disease: selective role for CD4 and CD8 T cells in inducing immune responses to self-antigens

BACKGROUND

The goal of this study was to define the role of T-cell sub-sets in the pathogenesis of autoimmunity-induced obliterative airway disease by passive transfer of CD8+ or CD4+ T cells.

METHODS

Antibodies to major histocompatibility complex (MHC) class I were administered intrabronchially into C57BL/6 animals. Lungs were analyzed by histopathology and immunohistochemistry. The CD8+ and CD4+ T-cell sub-sets were purified from the lung-infiltrating cells and intrabronchially transferred. Frequency of cells secreting interleukin-17, interferon-γ, or interleukin-10 to self-antigens was enumerated by enzyme-linked immunospot assay. Myeloperoxidase and antibodies to self-antigens were determined by enzyme-linked immunosorbent assay. Cytokine and growth factor expression was determined by quantitative reverse-transcription polymerase chain reaction.

RESULTS

Passive transfer of lung-infiltrating CD8 T cells isolated after anti-MHC class I administration, along with sub-optimal dose, induced significantly higher cellular infiltration (89.3% ± 7.9% vs 62.8% ± 10.1%, p < 0.05) vs the CD4 transfer group. Further, passive transfer of CD8 cells resulted in infiltration of neutrophils and macrophages, suggesting early injury response. In contrast, passive transfer of CD4+ T cells induced a significantly higher degree of luminal occlusion (29.3% ± 5.6% vs 8.6 ± 2.5%, p < 0.05) and fibrosis (54.4% ± 9.3% vs 10.2% ± 2.4%, p < 0.05) vs the CD8 group and B-cell infiltration, leading to immune responses to lung-associated self-antigens and fibrosis.

CONCLUSION

Ligation of MHC molecules by its specific antibodies induced early injury with neutrophils, macrophages, and CD8 T cells, which leads to exposure of cryptic self-antigens and their presentation by the infiltrating CD4+ T cells and B cells, leading to the development of immune responses to self-antigens and culminating in obliterative airway disease.