Number Of Granulomas Research Articles

Lack of cathepsin activities alter or prevent the development of lung granulomas in a mouse model of sarcoidosis

BackgroundRemodeling of lung tissues during the process of granuloma formation requires significant restructuring of the extra-cellular matrix and cathepsins K, L and S are among the strongest extra-cellular matrix degrading enzymes. Cathepsin K is highly expressed in various pathological granulomatous infiltrates and all three enzymes in their active form are detected in bronchoalveolar lavage fluids from patients with sarcoidosis. Granulomatous inflammation is driven by T-cell response and cathepsins S and L are actively involved in the regulation of antigen presentation and T-cell selection. Here, we show that the disruption of the activities of cathepsins K, L, or S affects the development of lung granulomas in a mouse model of sarcoidosis.MethodsApolipoprotein E-deficient mice lacking cathepsin K or L were fed Paigen diet for 16 weeks and lungs were analyzed and compared with their cathepsin-expressing littermates. The role of cathepsin S in the development of granulomas was evaluated using mice treated for 8 weeks with a potent and selective cathepsin S inhibitor.ResultsWhen compared to wild-type litters, more cathepsin K-deficient mice had lung granulomas, but individually affected mice developed smaller granulomas that were present in lower numbers. The absence of cathepsin K increased the number of multinucleated giant cells and the collagen content in granulomas. Cathepsin L deficiency resulted in decreased size and number of lung granulomas. Apoe-/- mice treated with a selective cathepsin S inhibitor did not develop lung granulomas and only individual epithelioid cells were observed.ConclusionsCathepsin K deficiency affected mostly the occurrence and composition of lung granulomas, whereas cathepsin L deficiency significantly reduced their number and cathepsin S inhibition prevented the formation of granulomas.

Pathologic lesions in chimpanzees (Pan trogylodytes schweinfurthii) from Gombe National Park, Tanzania, 2004-2010.

During a population decline or disease outbreak, the true risk of specific diseases to a wild population is often difficult to determine because of a lack of baseline disease information. To better understand the risk of disease in an endangered and scientifically important population of chimpanzees (Pan trogylodytes schweinfurthii), a health monitoring program was initiated in Gombe National Park, Tanzania. As part of this health monitoring program, comprehensive necropsies with histopathology were conducted on chimpanzees (n = 11; 5 male, 6 female), ranging in age from fetal to 44 yr, that were found dead between August 2004 and January 2010. In contrast to previous reports, respiratory disease was not noted as a cause of morbidity or mortality. Trauma was the most common cause of death in these 11 chimpanzees. All of the chimpanzees greater than 1 yr of age had intestinal and mesenteric parasitic granulomas associated with true strongyles consistent with Oesophagostomum spp. The relative numbers of granulomas increased with age and, in some cases, may have been a cause of weight loss and diarrhea. Simian immunodeficiency virus (SIV)cpz infection was documented in four deceased apes, all of whom exhibited varying amounts of lymphoid depletion including two females with marked CD4+ T cell loss consistent with endstage SIVmac or human immunodeficiency virus infections. Myocardial megalokaryosis was common in chimpanzees greater than 1 mo of age; yet myocardial interstitial fibrosis, a common lesion in captive chimpanzees, was uncommon and only noted in two aged chimpanzees. These findings provide important information on causes of morbidity and mortality in wild chimpanzees, information that can be used to interpret findings during population declines and lead to better management of this population in the context of disease risk.

Vitamin E reduces hepatic fibrosis in mice with Schistosoma japonicum infection

To investigate whether vitamin E protects against hepatic fibrosis in mice with Schistosoma japonicum infection, 24 pathogen-free Kunming mice were selected and randomly divided into four groups: control (uninfected, untreated), model (infected, untreated), low-dose intervention (infected, vitamin E-treated, 30 mg/g bodyweight/day) and high-dose intervention (infected, vitamin E-treated, 60 mg/g bodyweight/day). Mice were infected with Schistosoma japonicum by inoculating abdominal skin with snail hosts. The activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were detected in hepatic tissue by colorimetry. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type Ⅲ (PC-III) and type Ⅳ collagen (IV-C) were detected in the serum by radioimmunoassay. Finally, areas and numbers of granulomas were assessed through histopathology 42 days following treatment. The results revealed that mean areas of granulomas were smaller in the low- and high-dose intervention groups compared to those in the model group. Furthermore, the higher dose of vitamin E resulted in smaller granulomas than the low dose. The levels of LN, HA, PC-III and IV-C in the serum were lower following vitamin E treatment than in the model group. By contrast, activity of SOD, GPx and CAT in hepatic tissue was higher following vitamin E treatment compared to the model group. The activity of MDA was lower in hepatic tissue following vitamin E treatment compared to the model group, but was higher compared to controls. In general, the higher dose of vitamin E affected measurements to a greater extent than the lower dose. In conclusion, vitamin E treatment may reduce the growth of granulomas, slowing the process of hepatic fibrosis, and this effect may be the result of the altered activity of the oxidation-reduction enzyme system.

Granulomas in Crohn’s disease: does progression through the bowel layers affect presentation or predict recurrence?

The aim of the study was to correlate the presence and pattern of distribution of granulomas in resected specimens to clinical characteristics and outcome in patients undergoing surgery for Crohn's disease. Patients with Crohn's disease who underwent surgical resection between 2001 and 2007 were identified. Pathology slides were reviewed for the presence, number and location of granulomas in four representative slides from each specimen. Two-hundred and seven patients were identified. At a mean follow up of 14 months, 39 patients had a recurrence, 22 (57%) of whom underwent reoperation. Ninety-four (45%) patients had granulomas present in the surgical specimen. Patients with granulomas were younger (P<0.001), had a lower preoperative body mass index (P=0.037), were more likely to be female (P=0.017) and were more likely to have extra-intestinal manifestations (P=0.026) or perianal disease (P=0.012). Sites of disease and procedures performed were similar in both groups. Disease recurrence and reoperative rates were similar in both groups, as were length of stay and morbidity rates. The average number of granulomas present in each sampled pathology slide was 7.2, and there was no correlation between number of granulomas and disease severity. No link was found between the depth of involvement of the granulomas and fistulizing or stricturing disease. Granulomas were associated with increased extra-intestinal manifestations and perianal disease, a lower body mass index and younger or female patients. There was no correlation between the presence of granulomas and disease progression or recurrence rates during the short follow-up period of this study.

The outcome of acute schistosomiasis infection in adult mice with postnatal exposure to maternal malnutrition

Maternal malnutrition during the lactation period in early development may have long-term programming effects on adult offspring. We evaluated the combined effects of parasitological behaviour and histopathological features and malnutrition during lactation. Lactating mice and their pups were divided into a control group (fed a normal diet of 23% protein), a protein-restricted group (PR) (fed a diet containing 8% protein) and a caloric-restricted group (CR) (fed according to the PR group intake). At the age of 60 days, the offspring were infected with Schistosoma mansoni cercariae and killed at nine weeks post-infection. Food intake, body and liver masses, leptinaemia, corticosteronaemia, collagen morphometry and neogenesis and the cellular composition of liver granulomas were studied. PR offspring showed reduced weight gain and hypophagia, whereas CR offspring became overweight and developed hyperphagia. The pre-patent period was longer (45 days) in both programmed offspring as compared to controls (40 days). The PR-infected group had higher faecal and intestinal egg output and increased liver damage. The CR-infected group showed a lower number of liver granulomas, increased collagen neogenesis and a higher frequency of binucleate hepatocytes, suggesting a better modulation of the inflammatory response and increased liver regeneration. Taken together, our findings suggest that neonatal malnutrition of offspring during lactation affects the outcome of schistosomiasis in mice.

Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO(4)) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO(4)-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO(4) and Glu.SO(4)-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO(4)-LIPO and Glu.SO(4)) using a single dose. Parasitological analysis revealed that Glu.SO(4)-LIPO was as efficient as Glu.SO(4) in reducing egg elimination and worm burden. Treatment with free Glu.SO(4) and Glu.SO(4)-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63%, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO(4) or Glu.SO(4)-LIPO.

Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO4) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO4-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO4 and Glu.SO4-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO4-LIPO and Glu.SO4) using a single dose. Parasitological analysis revealed that Glu.SO4-LIPO was as efficient as Glu.SO4 in reducing egg elimination and worm burden. Treatment with free Glu.SO4 and Glu.SO4-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63%, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO4 or Glu.SO4-LIPO.

Lethal T- and NK-cell lymphomas mimicking granulomatous panniculitidies: a clinicopathologic study of three cases

An infiltrate mimicking subcutaneous panniculitis associated with a granulomatous response represents an uncommon histopathologic presentation of lymphoma. We report three cases, comprising one case each of nasal-type extranodal NK/T-cell lymphoma, cutaneous γ/δ T-cell lymphoma and human T-lymphotropic virus-I associated adult T-cell leukemia/lymphoma, which based on initial histopathologic and/or clinical presentation were thought to represent systemic lupus erythematosus, sarcoidosis and psoriasiform dermatitis, respectively. Excisional biopsies of indurated lesions performed at our institute; however, in each case showed an atypical subcutaneous lymphohistiocytic infiltrate associated with a variable number of granulomas. Extensive immunophenotypic characterization, in conjunction with histomorphologic and molecular analysis, established the diagnosis of lymphoma in all instances. All patients had a rapidly progressive clinical course and death was attributable to complications of lymphoma shortly after diagnosis. These cases highlight the importance of using a multimodality diagnostic approach to distinguish lymphomas masquerading as granulomatous panniculitis from inflammatory or reactive disorders associated with such histopathologic patterns.

Toll-Like Receptor 9 Is Required for Full Host Resistance to Mycobacterium avium Infection but Plays No Role in Induction of Th1 Responses

To investigate the role of Toll-like receptor 9 (TLR9) in innate immunity to Mycobacterium avium, TLR9, TLR2, and MyD88 knockout (KO) mice were infected with this bacterium. Bacterial burdens were higher in the spleens, livers, and lungs of infected TLR9 KO mice than in those of C57BL/6 mice, indicating that TLR9 is required for efficient control of M. avium infection. However, TLR9 KO or TLR2 KO spleen cells displayed normal M. avium-induced tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) responses. This finding was confirmed by determining the number of splenic CD4(+) T cells producing IFN-γ by flow cytometry. Furthermore, TLR2 and MyD88, but not TLR9, played a major role in interleukin-12 and TNF-α production by M. avium-infected macrophages and dendritic cells (DCs). We also found that major histocompatibility complex class II molecule expression on DCs is regulated by TLR2 and MyD88 signaling but not by TLR9. Finally, lack of TLR9, TLR2, or MyD88 reduced the numbers of macrophages, epithelioid cells, and lymphocytes in M. avium-induced granulomas but only MyD88 deficiency affected the number of liver granulomas. In summary, our data demonstrated that the involvement of TLR9 in the control of M. avium infection is not related to the induction of Th1 responses.

Control of Mycobacterium fortuitum and Mycobacterium intracellulare infections with respect to distinct granuloma formations in livers of BALB/c mice

Mycobacterium fortuitum is a rapidly growing nontuberculous Mycobacterium that can cause a range of diseases in humans. Complications from M. fortuitum infection have been associated with numerous surgical procedures. A protective immune response against pathogenic mycobacterial infections is dependent on the granuloma formation. Within the granuloma, the macrophage effector response can inhibit bacterial replication and mediate the intracellular killing of bacteria. The granulomatous responses of BALB/c mice to rapidly and slowly growing mycobacteria were assessed in vivo and the bacterial loads in spleens and livers from M. fortuitum and Mycobacterium intracellulare-infected mice, as well as the number and size of granulomas in liver sections, were quantified. Bacterial loads were found to be approximately two times lower in M. fortuitum-infected mice than in M. intracellulare-infected mice and M. fortuitum-infected mice presented fewer granulomas compared to M. intracellulare-infected mice. These granulomas were characterized by the presence of Mac-1+ and CD4+ cells. Additionally, IFN-γmRNA expression was higher in the livers of M. fortuitum-infected mice than in those of M. intracellulare-infected mice. These data clearly show that mice are more capable of controlling an infection with M. fortuitum than M. intracellulare. This capacity is likely related to distinct granuloma formations in mice infected with M. fortuitum but not with M. intracellulare.

Effects of Peg-Interferon-Alpha-2A on Schistosoma mansoni Infection in Mice

In some regions of the world, co-existence of schistosomiasis and hepatitis C (HCV) infection is common. Because the morbidity in human schistosomiasis is primarily due to host cell-mediated immune response, it was of interest to determine the effects on Schistosoma mansoni infection of an immune stimulator used in the standard treatment of HCV infection. Schistosoma mansoni -infected mice were treated with PEG-interferon-alpha-2a (PEG-IFN-alpha) by subcutaneous injection. Groups 1, 2, and 3 received 0.2 microg, 0.6 microg, and 1 microg PEG-IFN-alpha/wk, respectively, while group 4 received saline. The total worm burden was lower in all treated groups, with a maximal reduction of 35% after 9 wk of treatment with 1 microg PEG-IFN-alpha. Interferon treatment also increased the proportion of single worms over pairs. Ova counts in intestine and liver, as well as the number of liver granulomas, were greatly decreased at all time points for all treated groups. PEG-IFN-alpha also had inhibitory effects on the size of granulomas after 4 wk of treatment. The results suggest that PEG-IFN-alpha may be worth investigating for the treatment of human schistosomiasis when standard oral agents cannot be used, or when rapid inhibition of granuloma formation may be a priority.

Immunization with newly transformed Schistosoma mansoni schistosomula tegument elicits tegument damage, reduction in egg and parasite burden

The surface of the schistosomula is an important target for host immune system attack because the tegument represents the interface between host and parasite and thus is a potential candidate for the development of new intervention strategies. In this study, we evaluated the ability of schistosomula tegument (Smteg) to induce protection in mice. Immunization of mice with Smteg together with Freund adjuvant induced a Th1 type of immune response associated with a significant reduction in worm burden (43-48%), eggs trapped in the liver (65%), eggs eliminated in the faeces (59-60%) and granuloma number (41%). Lastly, during an in vitro study, worms from mice immunized with Smteg showed damage in the adult worm tegument and impaired egg laying.

Primary tuberculosis of the appendix in a young male patient: Report of a case

A 23-year-old man without a history of tuberculosis presented with right lower abdominal pain and a fever. An increased inflammatory response was found, and abdominal computed tomography showed a diffuse enlargement and wall thickening in the appendix. An ileocecal abscess and perforating appendicitis were suspected. Therefore, an emergency operation was performed. The surgery revealed a diffuse enlargement with adhesion to the retroperitoneum, which was suspected to be a neoplastic lesion of the appendix, thus an ileocecal resection including the appendix was performed. A histopathological examination revealed a number of epithelioid granulomas having Langerhans giant cells with caseous necrosis in the appendix, in addition to many granulomas without caseous necrosis in the regional lymph nodes. No tubercle bacilli were detected by Ziehl-Neelsen staining. Further examination revealed no tubercular lesions in other organs, thus leading to the diagnosis of primary tuberculosis of the appendix. This is an extremely rare disease reported in Japan.

SerpinB2 deficiency modulates Th1/Th2 responses after schistosome infection

SerpinB2, also known as plasminogen activator inhibitor type-2, is a major product of macrophages and is upregulated during many infections. Although SerpinB2 inhibits urokinase plasminogen activator in vitro, evidence that this represents its physiological role in vivo is not compelling. We have recently shown that SerpinB2-/-mice generate enhanced Th1 responses after immunization with a Th1 immunogen. Herein,we show that Schistosoma japonicum granulomas induced liver SerpinB2 mRNA expression by >600-fold in wild-type mice. In SerpinB2-/- mice, worm and egg burden, and granuloma number and volume were unaffected. However, granulomas in these mice were associated with reduced fibrosis (as determined by Sirius red staining and image analysis) and increased iNOS, IL-6, IL-10 and TNFa and decreased Arg 1 and IL-13 mRNA expression. SerpinB2-/- mice immunized with soluble egg antigen (SEA) also showed reduced levels of SEA-specific IgG1. SerpinB2 deficiency thus promoted certain Th1 and reduced certain Th2 responses in response to this Th2 immunogen.

Bioimmunological responses to Schistosoma mansoni and Fasciola gigantica worm homogenates either with or without saponin

In this study, we evaluated the biochemical, immunological, histopathological and antischistosomal activities of Schistosoma mansoni or Fasciola gigantica worm homogenates mixed either with or without saponin that was extracted from Atriplex nummularia. The immunization schedule was based on subcutaneous administration of two doses (50 microg /100 microl PBS) of each homogenate with time intervals of 15 days. After 15 days of the last homogenate inoculation, all mice were challenged with 100 Schistosoma mansoni cercariae and sacrificed after two months. Free radical scavengers and liver function enzymes were determined in mice liver. Worm counting and the histopathological picture of the liver were also done. Immunization with Schistosoma or Fasciola worm homogenates, mixed either with or without saponin, recorded an amelioration of the free radical scavenger levels, liver function enzymes and reduction in worm burden, as well as improvement of the histological feature of the liver, the number and size of granuloma, evidence of increased immune reaction manifested by a lymphocytic cuff surrounding the granuloma, diminution of its fibrotic and collagen content, and destruction of Schistosoma ova. Fasciola or Schistosoma worm antigens mixed with or without saponin succeeded to eliminate the product of oxidative stress and assistance in immune-mediated destruction of eggs that ameliorate the histopathological picture of the liver cells and preserve its function.

Age-related differences in granulomatous gastritis: a retrospective, clinicopathological analysis

BackgroundGranulomatous gastritis (GG) is an uncommon pathological finding that may accompany systemic disease, infections, foreign body reaction, malignancy or vasculitis, but may also be an isolated finding. Clinical and pathological...

ApoE-Deficient Mice on Cholate-Containing High-Fat Diet Reveal a Pathology Similar to Lung Sarcoidosis

Sarcoidosis is a chronic disease of unknown etiology characterized by the formation of non-necrotizing epithelioid granulomas in various organs, especially in the lungs. The lack of an adequate animal model reflecting the pathogenesis of the human disease is one of the major impediments in studying sarcoidosis. In this report, we describe ApoE-/- mice on a cholate-containing high-fat diet that exhibit granulomatous lung inflammation similar to human sarcoidosis. Histological analysis revealed well-defined and non-necrotizing granulomas in about 40% of mice with the highest number of granulomas after 16 weeks on a cholate-containing high-fat diet. Granulomas contained CD4+ and CD8+ T cells, and the majority of the cells in granulomas showed immunoreactivity for the macrophage marker Mac-3. Cells with morphological features of epithelioid cells expressed angiotensin-converting enzyme, osteopontin, and cathepsin K, all characteristics of epithelioid and giant cells in granulomas of human sarcoidosis. Giant cells and nonspecific inclusions such as Schaumann's bodies and crystalline deposits were also detected in some lungs. Granulomatous inflammation resulted in progressive pulmonary fibrosis. Removal of cholate from the diet prevented the formation of lung granulomas. The observed similarities between the analyzed mouse lung granulomas and granulomas of human sarcoidosis, as well as the chronic disease character leading to fibrosis, suggest that this mouse model might be a useful tool to study sarcoidosis.

Does granulocyte-colony stimulating factor administration induce damage or repair response in schistosomiasis?

To introduce Granulocyte-colony stimulating factor (G-CSF) as a new therapeutic modality for schistosomiasis through stem cell mobilization, immunomodulation or fibrosis remodeling. In this study, a 5 d course of human recombinant G-CSF (100 μg/kg sc) was applied to Schistosoma mansoni-infected mice at different stages of disease (5 d before infection as well as 3, 5 and 7 wk post-infection). The animals were sacrificed at 10 d as well as 4, 6 and 8 wk post infection. Mice were examined for: (1) Total leukocyte count which is an accepted surrogate marker for the stem cell mobilization into the circulation; (2) Egg count in intestine and liver tissue to assess the parasitic load; and (3) Histopathological changes in Hx/E and Masson trichrome stained sections as well as collagen content in Sirius red-stained liver sections to determine the severity of liver fibrosis. Mice developed leukocytosis. The egg load and the number of granulomas were not affected by the G-CSF treatment but there was an obvious change in the composition of granulomas towards an increased cellularity. Moreover, fibrosis was significantly decreased in treated groups compared to untreated animals (collagen content either preinfection or at 3 and 5 wk post infection: 5.8 ± 0.5, 4.7 ± 0.5, 4.0 ± 0.7 vs 8.2 ± 0.9; P ≤ 0.01). Although G-CSF did not cause direct elimination of the parasite, it enhanced granulomatous reaction and reduced the fibrosis. Further investigation of the underlying mechanisms of these two actions is warranted.

IPSE/alpha-1 ofSchistosoma mansoniegg induces enlargement of granuloma but does not alter Th2 balance after infection

Schistosomiasis is a parasitic disease with more than 200 million people infected worldwide. The formation of granulomas around eggs trapped in the liver is the main cause of disease morbidity. Therefore, the aim of this investigation was to characterize the immunopathological response induced by the recombinant (r) IPSE/alpha-1 egg protein in mice. Herein, we have shown that splenocytes from mice immunized with rIPSE/alpha-1 produced IFN-gamma, TNF-alpha, IL-4, IL-5 and IL-13 characterizing a mixed Th1/Th2 type of immune response. Pathological analysis of the liver revealed that there was no alteration in the number of eggs and granulomas; however, we observed an increase in granuloma area in immunized mice. Furthermore, eosinophil peroxidase assay showed that there was no alteration in the eosinophil infiltration in the liver; however, n-acetyl-beta-glucosaminidase measurement revealed an increase in macrophage activity. Despite the alteration in the profile of liver inflammatory cells in rIPSE immunized mice, the production of chemokines such as CCL2, CCL3, CCL5 and CCL11 was unaltered compared with the control group. In conclusion, IPSE/alpha-1 immunization induces a mixed Th1/Th2 type of immune response and enlargement of hepatic granuloma caused by an increased macrophage activity, but does not alter Th2 cytokines following infection.

SP-D counteracts GM-CSF-mediated increase of granuloma formation by alveolar macrophages in lysinuric protein intolerance

BackgroundPulmonary alveolar proteinosis (PAP) is a syndrome with multiple etiologies and is often deadly in lysinuric protein intolerance (LPI). At present, PAP is treated by whole lung lavage or with granulocyte/monocyte colony stimulating factor (GM-CSF); however, the effectiveness of GM-CSF in treating LPI associated PAP is uncertain. We hypothesized that GM-CSF and surfactant protein D (SP-D) would enhance the clearance of proteins and dying cells that are typically present in the airways of PAP lungs.MethodsCells and cell-free supernatant of therapeutic bronchoalveolar lavage fluid (BALF) of a two-year-old patient with LPI were isolated on multiple occasions. Diagnostic BALF samples from an age-matched patient with bronchitis or adult PAP patients were used as controls. SP-D and total protein content of the supernatants were determined by BCA assays and Western blots, respectively. Cholesterol content was determined by a calorimetic assay or Oil Red O staining of cytospin preparations. The cells and surfactant lipids were also analyzed by transmission electron microscopy. Uptake of Alexa-647 conjugated BSA and DiI-labelled apoptotic Jurkat T-cells by BAL cells were studied separately in the presence or absence of SP-D (1 μg/ml) and/or GM-CSF (10 ng/ml), ex vivo. Specimens were analyzed by light and fluorescence microscopy.ResultsHere we show that large amounts of cholesterol, and large numbers of cholesterol crystals, dying cells, and lipid-laden foamy alveolar macrophages were present in the airways of the LPI patient. Although SP-D is present, its bioavailability is low in the airways. SP-D was partially degraded and entrapped in the unusual surfactant lipid tubules with circular lattice, in vivo. We also show that supplementing SP-D and GM-CSF increases the uptake of protein and dying cells by healthy LPI alveolar macrophages, ex vivo. Serendipitously, we found that these cells spontaneously generated granulomas, ex vivo, and GM-CSF treatment drastically increased the number of granulomas whereas SP-D treatment counteracted the adverse effect of GM-CSF.ConclusionsWe propose that increased GM-CSF and decreased bioavailability of SP-D may promote granuloma formation in LPI, and GM-CSF may not be suitable for treating PAP in LPI. To improve the lung condition of LPI patients with PAP, it would be useful to explore alternative therapies for increasing dead cell clearance while decreasing cholesterol content in the airways.