The 110 kDa trans-membrane glycoprotein CD68 is highly expressed by human monocytes and tissue macrophages. However, in addition to the monocyte/macrophage system, CD68 has been also found in normal and tumor cells with no m
acrophagic activity such as lymphocytes, fibroblasts, endothelial cells, small intestinal epithelial cells, and neoplastic cells of different origins. Here, for the first time we demonstrate the immunohistochemical localization of CD68 in the principal cells of the cranial and caudal segments of rat epididymis. These results were confirmed by biochemical analyses showing the expression of CD68 mRNA transcripts and the protein in the epididymis tissues. Our findings, while providing further evidence that CD68 expression is not restricted to the monocyte/macrophage system, suggest that the glycoprotein might be involved in the functions of epididymal principal cells that contribute to spermatozoa maturation process.
Richardsen E, etal., Histopathology. 2008 May 28;.
Aims: Macrophage colony-stimulating factor (M-CSF) binds to colony-stimulating factor-1 receptor (CSF-1R) and stimulates proliferation and differentiation of monocytes, macrophages and their bone marrow progenitors. M-CSF, CSF-1R, the macrophage marker CD68, and
the pan T-lymphocyte marker CD3 are increased in many human cancers. Their prognostic importance in primary prostatic carcinoma has not been fully delineated. The aim was to compare the expression of M-CSF, CSF-1R, CD68 and CD3 in metastatic and non-metastatic prostatic cancer. Methods and results: Digital video analysis of tumour cell areas and tumour stromal areas was performed in 59 cancer specimens: 32 patients with metastases and 27 patients without metastases. Expression of M-CSF and CSF-1R was recorded as 0 (negative immunoreactivity), 1 (weak), 2 (moderate) or 3 (strong reactivity). Macrophages (CD68) and T lymphocytes (CD3) were detected as proportions of moderately or strongly immunoreactive cells. Patients with metastatic primary cancers showed higher expression of M-CSF (P < 0.0001, P = 0.005), CSF-1R (both P < 0.0001) and CD3 (P = 0.007, P < 0.0001) in both tumour cell areas and tumour stromal areas, compared with the non-metastatic cancers. Conclusion: This study suggests that expression of M-CSF, CSF-1R and CD3 is a significant prognostic factor in primary prostatic cancers by predicting the development of metastases.
AIM: The lack of potent innate immune responses during HCV infection might lead to a delay in initiating adaptive immune responses. Kupffer cells (KCs) and liver-infiltrating monocytes/macrophages (CD68+ cells) are essential to establish effective anti-HCV respo
nses. They express co-stimulatory molecules, CD80 and CD86. CD86 upregulation induces activator responses that are then potentially regulated by CD80. The relative levels of expression of CD80, CD86 and the inhibitory molecule, PD-L1, on CD68+ cells modulate T cell activation. A few studies have explored CD80 and PD-L1 expression on KCs and infiltrating monocytes/macrophages in HCV-infected livers, and none investigated CD86 expression in these cells. These studies have identified these cells based on morphology only. We investigated the stimulatory/inhibitory profile of CD68+ cells in HCV-infected livers based on the balance of CD80, CD86 and PD-L1 expression. METHODS: CD80, CD86 and PD-L1 expression by CD68+ cells in the lobular and portal areas of the liver of chronic HCV-infected (n = 16) and control (n = 14) individuals was investigated using double staining immunohistochemistry. RESULTS: The count of CD68+ KCs in the lobular areas of the HCV-infected livers was lower than that in the control (p = 0.041). The frequencies of CD68+CD80+ cells and CD68+PD-L1+ cells in both lobular and total areas of the liver were higher in HCV-infected patients compared with those in the control group (p = 0.001, 0.031 and 0.007 respectively). Moreover, in the lobular areas of the HCV-infected livers, the frequency of CD68+CD80+ cells was higher than that of CD68+CD86+ and CD68+PD-L1+ cells. In addition, the frequencies of CD68+CD80+ and CD68+CD86+ cells were higher in the lobular areas than the portal areas. CONCLUSIONS: Our results show that CD68+ cells have an inhibitory profile in the HCV-infected livers. This might help explain the delayed T cell response and viral persistence during HCV infection.
von Rahden BH, etal., Langenbecks Arch Surg. 2011 Aug;396(6):759-68. doi: 10.1007/s00423-011-0797-4. Epub 2011 May 7.
BACKGROUND: Immunosupression and, especially, intake of steroids have previously been identified as risk factors for complicated types of sigmoid diverticulitis. However, little is known about the underlying molecular and cellular mechanisms. We aimed to elucidate the potential role of ac
tivated macrophages in this respect. METHODS: A consecutive series of n = 101 patients having undergone surgical resection for sigmoid diverticulitis at our institution was analyzed regarding the inflammatory infiltrate and prevalence of comorbid diseases as well as risk factors, including steroid use. Fifty-seven patients had complicated types of diverticulitis with severe inflammation (group A). Forty-four patients had moderate inflammation, most of whom had been operated for chronically recurrent diverticulitis (group B). Randomly selected 50 patients (n = 20/group A/n = 30 group B) underwent immunolabelling against CD68 and CD163. RESULTS: Using immunofluorescence double labeling experiments we found a strong positive correlation of CD68 expression with CD163 expression (т = 0.934). High CD68 expression (x >= 23%) and high CD163 expression (x >= 22%) within stromal cells of the lamina propria was significantly associated with steroid use (CD68, p = 0.012 and CD163, p = 0.004, respectively) and complicated sigmoid diverticulitis with severe inflammation (CD68, p = 0.0001 and CD163, p = 0.001, respectively). CONCLUSIONS: Inflammation, especially mediated by activated (CD68+/CD163+) macrophages in histopathological specimen might resemble the cellular link between steroid use and complicated types of sigmoid diverticulitis. Macrophages might be a suitable target for future supportive/preventive therapies. However, as long as we are lacking such strategies, we must bear in mind that steroid intake is a risk factor for complicated diverticulitis, especially when indicating surgical resection.
S100A8 and S100A9 (S100 proteins) are regulators of immune cells of myeloid origin. Whereas S100 proteins are found at high concentrations in such cells, their immunologic roles remain unclear. We focused on cluster of differentiation 68 (CD68). The aim of this
study is to investigate whether CD68 binds to extracellular S100A8 and/or S100A9 and subsequently participates in the regulation of the cells' immune functions. ELISA and affinity chromatography showed that both recombinant rat S100A8 (r-S100A8) and r-S100A9 bound to r-CD68, but not to r-CD14. Flow cytometry clearly showed evidences supporting above the 2 results. As analyzed by flow cytometry, a less amount of r-S100A8 or r-S100A9 bound to the macrophages treated with some deglycosylation enzymes. In an in vitro assay, the expression levels of S100A8 and S100A9 were significantly suppressed after the macrophages had been treated with an anti-CD68 antibody (ED1). As stimulated macrophages with r-S100A9, the expression of IL-1β mRNA in macrophages, which were treated with anti-TLR4 or -RAGE antibodies, was significantly suppressed. r-S100A8 up-regulated IL-6 and IL-10 mRNAs, while r-S100A9 did TNF-α and IL-6 mRNAs, although these regulations were not statistically significant. Small interfering CD68 also significantly suppressed activation of macrophages through an autocrine pathway by r-S100A8 or r-S100A9. In macrophages stimulated with LPS, fluorescent immunologic staining showed that most CD68 colocalized with S100A8 or S100A9 and that the levels of all 3 molecules were markedly increased. In conclusion, CD68 on macrophages binds to S100A8 and S100A9 and thereby, plays a role in the regulation of the cells' immune functions.
Agur A, etal., Leuk Lymphoma. 2015 May;56(5):1315-9. doi: 10.3109/10428194.2014.963081. Epub 2014 Oct 9.
The prognostic role of CD68 tumor-associated macrophages in classic Hodgkin lymphoma (cHL) remains controversial. We stained diagnostic biopsies and scored for CD68 using the PGM1 antibody among 98 consecutive patients with
cHL from our center followed over a median of 45 months for progression-free survival (PFS). Among 79 patients we assessed interim and post-treatment positron emission tomography-computed tomography (PET-CT). Residual mass (RM) size was based on the greatest diameter of the largest mass seen in post-treatment imaging, and percent reduction was calculated by comparing RM size with its greatest pretreatment diameter. We found a significant association between CD68 positivity and absolute size of initial disease mass (p = 0.014) and residual mass at the end of therapy (p = 0.006) but no association was observed with interim PET-CT results or PFS. Our findings suggest that macrophages may influence tumor size by altering the microenvironment. This study does not support a prognostic role of CD68 positivity in predicting survival.
Touati M, etal., Leuk Lymphoma. 2015 Feb;56(2):332-41. doi: 10.3109/10428194.2014.917636. Epub 2014 Jun 27.
Finding new prognostic factors to identify patients with Hodgkin lymphoma (HL) at risk of treatment resistance or relapse remains challenging in daily practice. We evaluated the relationship between CD68 expression, interim positron emission tomography (iPET) re
sults and outcome in 158 patients with HL diagnosed from February 1995 to July 2011. Immunohistochemistry (anti-CD68) gave two groups: low with 25% (37 patients). Five-year overall survival was higher in the low group (88.4% vs. 63.2%, p=0.0151), as was progression-free survival (74.5% vs. 40.7%, p=0.0003). In 68 patients evaluable, iPET correlated with CD68: 13/52 patients (25%) in the low group had positive iPET as compared to 11/16 patients (68%) in the high group (p=0.0016). This study confirms the prognostic value of CD68 in HL. We found a correlation between CD68 and iPET suggesting potential for a better stratification.
Baldus SE, etal., Anal Cell Pathol. 1998;16(3):141-50. doi: 10.1155/1998/192975.
Liver macrophages, which are involved in the different types of hepatitis, may indirectly induce hepatic fibrogenesis, since they have the possibility to activate hepatic stellate cells and fibroblasts by secretion of TGF-beta, TNF-alpha and IL-1. To evaluate variations of the number of liver macrop
hages and their subpopulations, a quantification was carried out in normal human liver tissue, fatty liver, fatty liver hepatitis and hepatitis B. Identification was performed by the mab PG-M1 (anti-CD68) and, comparatively, four lectins, Griffonia simplicifolia agglutinin I (GSA-I), Erythrina cristagalli agglutinin (ECA), peanut agglutinin (PNA) and soybean agglutinin (SBA). A slight decrease in the frequency of macrophages in pericentral fields was observable in fatty liver and fatty liver hepatitis as compared to normal liver tissue. On the other hand, the number of CD68+ cells was significantly enhanced in hepatitis B with moderate and severe inflammatory activity. The highest incidence of macrophages was found in portal tracts of liver with fatty liver hepatitis and, particularly, hepatitis B. The fraction of cells stained by ECA, PNA or SBA did not increase significantly under pathological conditions. In contrast, the percentage of GSA-I binding macrophages was higher in liver parenchyma of hepatitis B and in portal tract macrophages in fatty liver hepatitis and also hepatitis B. In conclusion, our results indicate that GSA-I may aid in the detection of the subpopulation of activated macrophages which are assumed to play a pivotal role in liver pathology.
Greaves P, etal., J Clin Oncol. 2013 Jan 10;31(2):256-62. doi: 10.1200/JCO.2011.39.9881. Epub 2012 Oct 8.
PURPOSE: The immune microenvironment is key to the pathophysiology of classical Hodgkin lymphoma (CHL). Twenty percent of patients experience failure of their initial treatment, and others receive excessively toxic treatment. Prognostic scores and biomarkers have yet to influence outcomes
significantly. Previous biomarker studies have been limited by the extent of tissue analyzed, statistical inconsistencies, and failure to validate findings. We aimed to overcome these limitations by validating recently identified microenvironment biomarkers (CD68, FOXP3, and CD20) in a new patient cohort with a greater extent of tissue and by using rigorous statistical methodology. PATIENTS AND METHODS: Diagnostic tissue from 122 patients with CHL was microarrayed and stained, and positive cells were counted across 10 to 20 high-powered fields per patient by using an automated system. Two statistical analyses were performed: a categorical analysis with test/validation set-defined cut points and Kaplan-Meier estimated outcome measures of 5-year overall survival (OS), disease-specific survival (DSS), and freedom from first-line treatment failure (FFTF) and an independent multivariate analysis of absolute uncategorized counts. RESULTS: Increased CD20 expression confers superior OS. Increased FOXP3 expression confers superior OS, and increased CD68 confers inferior FFTF and OS. FOXP3 varies independently of CD68 expression and retains significance when analyzed as a continuous variable in multivariate analysis. A simple score combining FOXP3 and CD68 discriminates three groups: FFTF 93%, 62%, and 47% (P < .001), DSS 93%, 82%, and 63% (P = .03), and OS 93%, 82%, and 59% (P = .002). CONCLUSION: We have independently validated CD68, FOXP3, and CD20 as prognostic biomarkers in CHL, and we demonstrate, to the best of our knowledge for the first time, that combining FOXP3 and CD68 may further improve prognostic stratification.
We studied by immunohistochemistry the background CD20 + cells in 131 cases of classical Hodgkin lymphoma (cHL). High CD20 + dispersed cells (CD20BG) showed a significant correlation with longer overall survival (OS) and a trend toward improved progression-free survival (PFS). At multivariate analys
is high CD20BG was also an independent prognostic factor of improved PFS and OS. The prognostic role of CD20BG seems to be opposite with respect to tumor associated macrophages (TAMs) we studied previously in most cases of the series. We scored patients on the basis of the respective CD20BG and TAM count and found that the combination of low CD20BG and high TAMs was related to a significantly reduced PFS and OS at univariate and multivariate analysis. Microenvironment CD20 + cells seem to play a favorable prognostic role in cHL. Depletion of CD20 + cells together with an increase of TAMs identifies a group of patients with high-risk disease.
The aims of the present study were to determine whether the changes in density and location of CD68-positive and CD206-positive macrophages contribute to progression of hepatocellular carcinoma (HCC) and to evaluate prognostic values of these cells in post-surgi
cal patients. A retrospective study involving 268 HCC patients was conducted. CD68-positive and CD206-positive macrophage infiltration in HCC tissues and adjacent tissues was examined by immunohistochemistry (IHC) and the relationship between the clinicopathological features and prognosis was analyzed. Receiver operating characteristics (ROC) curve was used to calculate diagnostic accuracy. There was an increase in CD68-positive and CD206-positive macrophage infiltration in adjacent tumor tissues compared with tumor tissues. ROC curve identified their optimal diagnostic cut-off values. The survival analysis showed that increased CD68 expression in adjacent tissues conferred superior overall survival (OS) and disease-free survival (DFS), while increase of CD206 in tumor yielded inferior OS and DFS. Cox regression analysis suggested both CD68-positive macrophages in adjacent area and intratumor CD206-positive macrophages as independent prognostic biomarkers for post-surgical HCC patients. Finally, a combination of CD68/CD206 and HBV-positive further improved prognostic stratification, especially in DFS. These results provide the first evidence for region- and subset-dependent involvement of CD68 and CD206 cells in HCC progression. A combination of CD68/CD206 density and HBV-positivity improves further predictive value for post-operative recurrence of HCC. Quantification of CD68/CD206 macrophages and their distribution can be exploited for better postsurgical management of HCC patients. These findings provide a basis for developing novel treatment strategies aimed at re-educating macrophages in tumor microenvironment.
Tousson E, etal., Biomed Pharmacother. 2014 Jun;68(5):631-9. doi: 10.1016/j.biopha.2014.05.007. Epub 2014 Jun 13.
Amethopterin (methotrexate, MTX) is an antimetabolite and antifolate drug with antiflammatory properities and is used to treat autoimmune diseases, such as psoriasis, rheumatoid arthritis and certain types of cancer, such as breast, lymphoma and lung. The present study aimed to study the changes in
P53, Bcl-2 and CD68 expression in response to amethopterin-induced lung injury and ameliorating the role of l-carnitine. A total of 36 male albino rats were equally divided into six groups: the first and second groups were the control and l-carnitine groups respectively while the 3rd group was amethopterin rat group; the 4th and 5th groups were co- and post-treated amethopterin rat with l-carnitine respectively and the 6th group was self treated amethopterin rat group. Our results shows that lung in amethopterin-treated rats showed many of histopathological alterations as severe to strong alveolar damage in the form of collapsed alveoli and strong thickened interalveolar septa with heavy infiltration of inflammatory cells. This damage was increased or remaining in self-amethopterin-treated group. Treatment (co- and post) with l-carnitine were improved in the lung structure that was treated with amethopterin. A significant increase in p53 and CD68 and decrease in Bc1-2 immunoreactivity in the lung in amethopterin group is observed when compared with the control group. However, treatment of rats with l-carnitine decreased the intensity of P53-ir and CD68-ir and increased the intensity of Bcl-2 in lung when compared with amethopterin rat group. Co-treatment with l-carnitine improved lung damage induced with amethopterin.
In this work, we aimed to evaluate the levels of ferritin enriched in H subunits (H-ferritin) and ferritin enriched in L subunits (L-ferritin) and the cells expressing these two molecules in the lymph node (LN) biopsies obtained from adult-onset Still's disease (AOSD) patients, and the possible cor
relation among these data and the severity of the disease. Ten patients with AOSD underwent LN biopsy. All the samples were stained by immunofluorescence. A statistical analysis was performed to estimate the possible correlation among both H-ferritin and L-ferritin tissue expression and the clinical picture of the disease. Furthermore, the same analysis was performed to evaluate the possible correlation among the number of CD68(+)/H-ferritin(+) or CD68(+)/L-ferritin(+) cells and the clinical picture. Immunofluorescence analysis demonstrated an increased tissue H-ferritin expression in the LNs of AOSD patients. This increased expression correlated with the severity of the disease. An increased number of CD68 macrophages expressing H-ferritin was observed in the LN samples of our patients. Furthermore, we observed that the number of CD68(+)/H-ferritin(+) cells correlated significantly with the severity of the clinical picture. Our data showed an imbalance between the levels of H- and L-ferritin in LNs of AOSD patients and the evidence of an increased number of CD68(+)/H-ferritin(+) cells in the same organs. Furthermore, a correlation among both the tissue H-ferritin levels and the CD68(+)/H-ferritin(+) cells and the clinical picture was observed.
