Local Cellular Immune Response Research Articles

Histopathological, Immunohistochemical and Exfoliative Cytological Studies of Oral Verruciform Xanthoma

Verruciform xanthoma is a rare tumor-like lesion, predominantly affecting the oral mucosa. Although several studies of verruciform xanthoma have been reported, the characteristic features and pathogenesis have not been fully clarified. The purpose of the present study is to perform immunohistochemical analysis using markers of proliferative cell activity and cytokeratins, and to perform comparative analysis between cytological and histological features in order to clarify the characteristic features of verruciform xanthomas. Histological findings showed exophitic proliferation of stratified squamous epithelium and accumulation of foamy macrophages between epithelial processes. Immunohistochemically, accumulated foamy cells showed positive immuno-reactivity for CD68, and positive cells were also present in the epithelium. Expression of pancy-tokeratin was observed in most layers of the epithelium, whereas cytokeratin 13 was also detected in prickle cell layers. Positive reactivity for Ki-67 was observed in epithelial cell nuclei. Positive reactivity was largely distributed in basal and/or parabasal cell layers, and the positive cell rate was 20%. In addition, exfoliative cytological findings showed hyperkeratotic epithelial cells with picnosis, thus suggesting the characteristics of hyperplastic epithelium in verruciforma, although foamy cells were not observed in the cytological specimens. These results suggest that benign morphological characteristics with local cellular immune response of verruciform xanthoma may be evaluated based on immunohistochemical expression of cytokeratin and Ki-67, as well as exfoliative cytological findings.

Type V Collagen–induced Tolerance Prevents Airway Hyperresponsiveness

Type V Collagen–induced Tolerance Prevents Airway Hyperresponsiveness

CD4+ CD25+ FOXP3+ regulatory T cells in peripheral blood and peritoneal fluid of patients with endometriosis

Is endometriosis associated with changes in CD4⁺ CD25⁺ FOXP3⁺ regulatory T cells (Treg cells)? Endometriosis is associated with disturbed compartmentalization of CD25(high) FOXP3⁺ Treg cells. Endometriosis is associated with an abrogated immune response and displays some features of an autoimmune disorder. Treg cells play a part in the development of autoimmune reactions; however, their role in pathogenesis of endometriosis is still poorly recognized. Case-control study comparing 17 women with laparoscopically and histopathologically confirmed ovarian endometriosis with 15 control women without visible endometriosis foci, pelvic inflammation or related pathology who were subjected to laparoscopic surgery between 2010 and 2011. Peripheral blood and peritoneal fluid were collected during laparoscopy and T cell subpopulations were analysed by flow cytometry using specific monoclonal antibodies recognizing CD4⁺, CD25⁺ and FOXP3⁺ markers. The percentage of CD25(high) FOXP3⁺ Treg cells was significantly decreased in the peripheral blood of women with ovarian endometriosis compared with control women. On the other hand, the proportion of these cells was significantly increased in the peritoneal fluid of women with endometriosis. The present study is limited to patients with ovarian endometrioma and further investigations are needed, including patients with lower grade of endometriosis. The present results suggest that Treg cells may play a part in immunopathogenesis of endometriosis being responsible for abrogated local cellular immune responses and facilitation and development of autoimmune reactions. Treg cells may be thus a potential target in the treatment of endometriosis. This study was supported by 1M15/N/2011 and NK1W grants from the I Faculty of Medicine, Warsaw Medical University. None of the authors has any competing interests to declare.

Co-administration of attenuated Mycoplasma hyopneumoniae 168 strain with bacterial DNA enhances the local and systemic immune response after intranasal vaccination in pigs

Mycoplasma hyopneumoniae, the primary pathogen of enzootic pneumonia, occurs worldwide and causes major economic losses to the pig industry. M. hyopneumoniae infects pigs at mucosal surfaces of respiratory tract. The aim of the present study was to investigate if the protection rate against M. hyopneumoniae infection following intranasal immunization with attenuated M. hyopneumoniae 168 strain is improved by administration of bacterial DNA containing CpG motifs. Thirty pigs were immunized intranasally or intramuscularly and the levels of local respiratory tract and systemic immune responses were detected. The results showed that the number of intraepithelial lymphocytes in the tracheal fork, the levels of cytokine IL-6, and M. hyopneumoniae specific SIgA in local nasal cavity increased respectively after intranasal vaccination with the attenuated M. hyopneumoniae 168 strain alone. However, the levels of IL-10 and IFN-γ in local nasal cavity, the number of intraepithelial lymphocytes in trachea, CD4(+) and CD8(+) T lymphocytes in the lung and hilar lymph nodes, the specific IgG antibody level in serum on 35 day post immunization were all increased significantly after intranasal vaccination of the attenuated M. hyopneumoniae 168 strain adjuvanted with bacterial DNA. We concluded that intranasal administration of attenuated M. hyopneumoniae 168 strain adjuvanted with bacterial DNA may be effective in evoking the local cellular and humoral immune response in the respiratory tract and the systemic immune response. Intranasal vaccination will be effective in prevention of the transmission and prevalence of MPS.

The role of tumor cells in the modification of T lymphocytes activity — the expression of the early CD69<sup>+</sup>, CD71<sup>+</sup> and the late CD25<sup>+</sup>, CD26<sup>+</sup>, HLA/DR<sup>+</sup> activation markers on T CD4<sup>+</sup> and CD8<sup>+</sup> cells in squamous cell laryngeal carcinoma. Part I

The role of interactions between tumor cells and autologous immunocompetent cells, the impact on the modulation of the activity of T CD4(+) and CD8(+) lymphocytes, as well as the influence on the regulation and determination of antitumor cellular immune response in patients with head and neck squamous cell carcinomas (HNSCC) is not completely clear. The aim of this study was to analyze early and late activation antigens expression on T cells subpopulations modified under the influence of the presence of cancer cells to investigate the regulatory mechanisms of the local cellular immune response in carcinoma of the larynx. Cytofluorymetric analysis of the early (CD69(+), CD71(+)) and late activation markers (CD25(+) (high), CD26(+), HLA/DR(+)) expression on T CD3(+)CD4(+) and CD3(+)CD8(+) cells subpopulations in mixed cellular cultures of freshly isolated tumor cells (MLTMC) and non-cancerous normal epithelial cells (MLNCC) with immunocompetent cells was performed in 55 cases of squamous cell laryngeal carcinoma. The whole peripheral blood concentrations of IL-10 and IFN-γ in 21 h and 72 h of experiments were also measured by ELISA. The relationships between the activation markers expression depending on the type of cells used in co-cultures, as well as the level of secreted cytokines, were investigated. Our work has revealed a statistically significant dependence of cytofluorymetric results on the presence of TMC or NCC in mixed cellular cultures. Increased expression of CD69(+), CD71(+) and CD25(+) (high), CD26(+), HLA/DR(+) antigens on T CD3(+)CD4(+) and CD3(+)CD8(+) cells was higher in MLTMC cultures, in comparison with MLNCC. We demonstrated negative significant relationships of IFN-γ and IL-10 secretion with regard to CD4(+)CD69(+), CD8(+)CD69(+), CD4(+)CD71(+), CD8(+)CD71(+) antigens expression in 21 h of experiments without mitogenic stimulation. Furthermore, this study revealed negative significant relationships of IFN-g secretion with regard to CD4(+)HLA/DR(+) and CD8(+)HLA/DR(+) as well as between IL-10 concentration and CD4(+)HLA/DR(+) in trials without PHA stimulation. Our findings have confirmed a key role for tumor cells in determining the function of T cells involved in the immunological processes and impact of neoplastic cells on modulating the activity of T CD4(+) and CD8(+) lymphocytes in laryngeal carcinoma.

Vaccine-specific antibody secreting cells are a robust early marker of LAIV-induced B-cell response in ferrets

Currently, a robust set of immune correlates for live attenuated influenza vaccine (LAIV) efficacy in humans has not been fully elucidated. The serum hemagglutination inhibition (HAI) assay has been historically used to measure humoral immune responses to injectable inactivated influenza vaccination. However, serum antibody titers do not reliably reflect the complete mechanism of action of LAIV, which is an intranasally delivered vaccine and is expected to induce local mucosal and cellular immune responses in addition to humoral immune responses. Therefore, we designed a study to evaluate potential immune correlates of LAIV vaccination in the ferret animal model of influenza infection. Ferrets were vaccinated with increasing doses of LAIV and four weeks later challenged with a homologous wild-type (wt) H1N1 strain. Humoral immune responses measured following LAIV vaccination included HAI, serum antibodies and antibody secreting cells (ASC); and the responses were found to correlate with the dose level of LAIV administered in this model. Protection from wt virus challenge was determined by measuring inhibition of wt viral replication in nasal washes and in lung tissue. Results demonstrated that LAIV doses ≥ 5.0 log(10) Plaque Forming Units (PFU) elicited vaccine-specific IgG and IgA ASC frequencies and induced complete protection in the lungs. Further, we developed a novel model utilizing seropositive older ferrets to demonstrate that in the background of previous wt influenza infection LAIV induces a robust vaccine-specific B-cell response even in the absence of serum antibody response, a result that suggests that effector B-cell responses generated by LAIV are not inhibited by prior viral exposure. Finally, we demonstrated that LAIV elicits strain-specific memory B-cell responses that are measurable in a background of wt influenza infections. Taken together, results from these studies identified the antigen-specific ASC frequency as a useful early biomarker of LAIV-induced B-cell immune response.

Evaluation of the Sublingual Route for Administration of Influenza H5N1 Virosomes in Combination with the Bacterial Second Messenger c-di-GMP

Avian influenza A H5N1 is a virus with pandemic potential. Mucosal vaccines are attractive as they have the potential to block viruses at the site of entry, thereby preventing both disease and further transmission. The intranasal route is safe for the administration of seasonal live-attenuated influenza vaccines, but may be less suitable for administration of pandemic vaccines. Research into novel mucosal routes is therefore needed. In this study, a murine model was used to compare sublingual administration with intranasal and intramuscular administration of influenza H5N1 virosomes (2 µg haemagglutinin; HA) in combination with the mucosal adjuvant (3′,5′)-cyclic dimeric guanylic acid (c-di-GMP). We found that sublingual immunisation effectively induced local and systemic H5N1-specific humoral and cellular immune responses but that the magnitude of response was lower than after intranasal administration. However, both the mucosal routes were superior to intramuscular immunisation for induction of local humoral and systemic cellular immune responses including high frequencies of splenic H5N1-specific multifunctional (IL-2+TNF-α+) CD4+ T cells. The c-di-GMP adjuvanted vaccine elicited systemic haemagglutination inhibition (HI) antibody responses (geometric mean titres ≥40) both when administered sublingually, intranasally and inramuscularly. In addition, salivary HI antibodies were elicited by mucosal, but not intramuscular vaccination. We conclude that the sublingual route is an attractive alternative for administration of pandemic influenza vaccines.

Patterns of Lesion and Local Host Cellular Immune Response in Natural Cases of Ovine Maedi-Visna

This study investigates the nervous form of ovine maedi-visna by histological and immunohistochemical techniques. The aim was to study the lesion types and the local cellular immune response related to each lesion type, and the possible relationship between these parameters. Thirty-four Assaf ewes were studied, 29 of which had shown nervous signs. Microscopical lesion patterns were described according to location, extent and predominance of inflammatory cell type. Immunohistochemical labelling of T cells (CD3(+), CD4(+), CD8(+) and cells expressing the γδ form of the T-cell receptor), B cells and macrophages revealed clear differences between the lesion patterns. Two main lesion types were described. Lymphocytic lesions had areas of mild-moderate injury characterized by a predominance of infiltrating T cells. Histiocytic lesions were more severe and had extensive areas of malacia and dominant infiltration by macrophages and B cells. Each animal had a unique lesion pattern and these differences could be due to individual resistance to the progression of infection. Thelymphocytic lesions appear to represent initial or latent phases of slow progression, in which the animal presents some natural resistance to the infection. The histiocytic pattern may reflect a poor immune response or a greater virulence of the viral strain.

Intra‐arterial methylprednisolone for the management of steroid‐refractory acute gastrointestinal and hepatic graft versus host disease

Intra‐arterial methylprednisolone for the management of steroid‐refractory acute gastrointestinal and hepatic graft versus host disease

Mycobacterium tuberculosis Culture Filtrate Protein 10-Specific Effector/Memory CD4+and CD8+T Cells in Tubercular Pleural Fluid, with Biased Usage of T Cell Receptor Vβ Chains

T cell-mediated immunity is critical for the control of Mycobacterium tuberculosis infection. Identifying the precise immune mechanisms that lead to control of initial M. tuberculosis infection and preventing reactivation of latent infection are crucial for combating tuberculosis. However, a detailed understanding of the role of T cells in the immune response to infection has been hindered. In addition, there are few flow cytometry studies characterizing the Vβ repertoires of T cell receptors (TCRs) at local sites of M. tuberculosis infection in adult tuberculosis. In this study, we used culture filtrate protein 10 (CFP-10) from M. tuberculosis to characterize T cells at local sites of infection. We simultaneously analyzed the correlation of the production of cytokines with TCR Vβ repertoires in CFP-10-specific CD4(+) and CD8(+) T cell subsets. For the first time, we demonstrate that CFP-10-specific CD4(+) or CD8(+) T cells from tubercular pleural fluid can produce high levels of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and upregulate the expression of CD107a/b on the cell surface. The CFP-10-specific cells were effector/memory cells with a CD45RO(+) CD62L(-) CCR7(-) CD27(-) expression profile. In addition, we found CFP-10-specific CD4(+) and CD8(+) T cells in tubercular pleural fluid, with biased usage of TCR Vβ9, Vβ12, or Vβ7.2. Our findings of CFP-10-specific CD4(+) and CD8(+) T cells in tubercular pleural fluid are critical for understanding the mechanisms of the local cellular immune response and developing more effective therapeutic interventions in cases of M. tuberculosis infection.

Maternal Immune Responses to Trophoblast: The Contribution of the Horse to Pregnancy Immunology

The horse has proven to be a distinctively informative species in the study of pregnancy immunology for several reasons. First, unique aspects of the anatomy and physiology of the equine conceptus facilitate approaches that are not possible in other model organisms, such as non-surgical recovery of early stage embryos and conceptuses and isolation of pure trophoblast cell populations. Second, pregnant mares make strong cytotoxic antibody responses to paternal major histocompatibility complex class I antigens expressed by the chorionic girdle cells, permitting detailed evaluation of the antigenicity of these invasive trophoblasts and how they affect the maternal immune system. Third, there is abundant evidence for local maternal cellular immune responses to the invading trophoblasts in the pregnant mare. The survival of the equine fetus in the face of strong maternal immune responses highlights the complex immunoregulatory mechanisms that result in materno-fetal tolerance. Finally, the parallels between human and horse trophoblast cell types, their gene expression, and function make the study of equine pregnancy highly relevant to human health. Here, we review the most pertinent aspects of equine reproductive immunology and how studies of the pregnant mare have contributed to our understanding of maternal acceptance of the allogeneic fetus.

Liposomal oral DNA vaccine (mycobacterium DNA) elicits immune response

Tuberculosis is one of the leading causes of mortality from an infectious disease worldwide, however, the efficacy of BCG vaccine against adult pulmonary tuberculosis still remains instability. Therefore, it is an urgent work to develop both safe and effective vaccine to TB.To clarify the liposome encapsulated DNA vaccine was effectively working as a vaccine delivery system to evoke mucosal intestinal immune responses. A Mycobacterium pcDNA3.1+/Ag85A DNA was constructed and encapsulated into liposome. Ag85A protein antigen was observed to substantially express in the epithelium, microfold cells (M cells), dendritic cells (DCs) and Peyer's patches (pp) of the small intestine, respectively, after oral administration into C57BL/6 mice 3 times each 14 days interval. Furthermore, levels of IL-2 and IFN-γ in the IELs isolated from the small intestine were markedly increased, IL-4 level was not significantly changed as compared to those in control group after oral administration of Ag85A DNA encapsulated in liposome, together with the augmented Ag85A-specific cytotoxicity of IELs, indicating a local Th1 dominant cellular immune response was elicited, and thus enhanced cytotoxicity of IELs as compared to those in control mice. Furthermore, sIgA level was also elevated in liposomal encapsulated Ag85A DNA immunized mice. These data indicated that oral vaccination with the liposomal-pcDNA 3.1+/Ag85A DNA is able to induce antigen specific mucosal cellular and humoral immune responses. Especially, cellular compartment in the epithelium of small intestine plays a key role on the regulation of immune response to eliminate TB. These findings have important understanding and possible implications for the design of new strategies based on oral DNA vaccine on regulation of immune response in protection against TB. Further study is clearly necessary to improve the effectiveness of Ag85A DNA vaccines against TB as compared with BCG.

Evaluation of Hepatic Damage and Local Immune Response in Goats Immunized with Native Glutathione S-transferase of Fasciola hepatica

Worm burden, hepatic damage and local cellular and humoral immune responses were assessed in goats immunized with glutathione-S-transferase and challenged with Fasciola hepatica. Infected but unimmunized and uninfected control groups were also studied. Hepatic damage was evaluated grossly and microscopically. Local immune response was evaluated by (1) microscopical examination of hepatic lymph nodes (HLNs); (2) analysis of the distribution of CD2(+), CD4(+), CD8(+), T-cell receptor gammadelta(+) lymphocytes and immunoglobulin (Ig) G(+) plasma cells; and (3) investigation of the distribution of cells expressing interleukin (IL)-4 and interferon (IFN)-gamma in the hepatic inflammatory infiltrates and HLNs. Immunized animals did not have significant reduction in fluke number, but there was significant (P<0.05) reduction of fluke size relative to the control groups. The lesions in the two infected groups were similar and consisted of fibrous perihepatitis and white tortuous tracts, mainly involving the left hepatic lobe. Microscopical lesions were similar in both infected groups and were typical of chronic fascioliosis. These included portal fibrosis, inflammatory infiltration with plasma cells, formation of lymphoid follicles, accumulation of haemosiderin-laden macrophages and granulomatous foci. Both infected groups had a marked local immune response characterized by infiltration of CD2(+), CD4(+) and CD8(+) T lymphocytes, and IgG(+) plasma cells in hepatic lesions and in HLNs. There was no expression of IL-4 or INF-gamma by cells in the hepatic inflammatory infiltrate, but expression of INF-gamma in HLNs was much lower than that of IL-4, suggesting an immune response dominated by T helper 2 cells.

Oral Vaccination with the Porcine Rotavirus VP4 Outer Capsid Protein Expressed byLactococcus lactisInduces Specific Antibody Production

The objective of this study to design a delivery system resistant to the gastrointestinal environment for oral vaccine against porcine rotavirus. Lactococcus lactis NZ9000 was transformed with segments of vP4 of the porcine rotavirus inserted into the pNZ8112 surface-expression vector, and a recombinant L. lactis expressing VP4 protein was constructed. An approximately 27 kDa VP4 protein was confirmed by SDS-PAGE , Western blot and immunostaining analysis. BALB/c mice were immunized orally with VP4-expression recombinant L. lactis and cellular, mucosal and systemic humoral immune responses were examined. Specific anti-VP4 secretory IgA and IgG were found in feces, ophthalmic and vaginal washes and in serum. The induced antibodies demonstrated neutralizing effects on porcine rotavirus infection on MA104 cells. Our findings suggest that oral immunization with VP4-expressing L. lactis induced both specific local and systemic humoral and cellular immune responses in mice.

The positive adjuvant effect of chitosan on antigen-specific cell-mediated immunity after chickens vaccination with live Newcastle disease vaccine

The development of safe, novel strong adjuvants is necessary to maximize the efficacy of and the immune response induced by new and/or available vaccines administered through the mucosal route to chickens. Chitosan is a non-toxic, biocompatible, biodegradable and natural polysaccharide derived from the exoskeleton of crustaceans and insects. It has been demonstrated to be an effective absorption enhancer to improve mucosal delivery of peptide and protein drugs in human and mice. In poultry, mucosal administration of live vaccine has been already explored with success. However, the effects of the use of the chitosan as adjuvant for mucosal vaccination in birds have not been investigated yet. To this aim, we explored its potential as adjuvant given by oculo-nasal route to one-day-old chickens with live Newcastle disease (ND) vaccine. The immune response has been evaluated during three independent vaccination experiments on specific pathogen free (SPF) chickens. It was shown that chitosan enhanced the antigen-specific cell-mediated immune response in the spleen. New protocols were developed to measure the chicken IFNγ production after ex vivo antigen-stimulation of peripheral blood and duodenal lamina propria lymphocytes. It was then observed than the peripheral cellular immune response was earlier and stronger, while the local cellular immune response in digestive tract as shorter when chitosan was used as adjuvant. On the other hand, the chitosan had no effect on the systemic, lachrymal and digestive antibody-mediated immunity. This study indicates thus that the chitosan is a cell-promising adjuvant for the mucosal delivery of live vaccine in poultry, by enhancing the Th1 pathway of immunity. However, further investigations are required to explore its mechanism of action and to evaluate the inferred protection.

Local cellular immune response induced by ultrasound-guided tumor bed superantigen injection after percutaneous microwave coagulation therapy for liver cancer

To investigate the local cellular immune response after injection of superantigen, the highly agglutinative staphylococin (HAS), into the tumor bed after ultrasound-guided percutaneous microwave coagulation therapy (PMCT) in the liver cancer patients. Ninety-two patients with pathologically proven primary liver cancer were divided into two groups: 45 in group A were treated by PMCT alone and 47 in the group B by combined with ultrasound-guided percutaneous injection of highly agglutinative staphylococin (HAS). Before and after PMCT and HAS treatment, the patients underwent ultrasound-guided percutaneous biopsy from the tumor bed and the samples were examined by pathology and immunohistochemistry. The infiltration of CD3+, CD4+, CD57+ and CD68+ lymphocytes in treatment zone was compared between the two groups. Moreover, the infiltrating immunocytes were observed by transmission electron microscopy. One week after HAS injection, the densities of CD3+, CD4+, CD57+ and CD68+ cells in the group B were 54.50 +/- 18.44, 38.14 +/- 12.44, 33.38 +/- 10.79 and 45.56 +/- 16.53, respectively. All the above mentioned parameters increased significantly in varying degrees compared with that before PMCT or HAS injection (P < 0.05). Four weeks after HAS injection, the density of CD3+, CD4+, CD57+ and CD68+ cells in the group B were 32.67 +/- 10.42, 23.43 +/- 6.99, 18.63 +/- 7.89 and 30.01 +/- 11.05, respectively, still significantly higher than those before PMCT (P < 0.05). Five weeks after PMCT and HAS injection, the densities of CD3+, CD4+, CD57+ and CD68+ cells in the group B were 54.50 +/- 18.44, 38.14 +/- 12.44, 33.38 +/- 10.79 and 45.56 +/- 16.53, versus 32.03 +/- 8.11, 15.67 +/- 8.32, 15.23 +/- 8.26 and 29.67 +/- 11.98 in the group A, respectively, still with a significant difference between the two groups (P < 0.05). A lot of lysosomes, endoplasmic reticulum and mitochondria in the immune cells after injection of HAS were observed by transmission electron microscopy. The local cellular immunity in liver cancer treatment area can be significantly improved by ultrasound-guided injection of highly agglutinative staphylococin after percutaneous microwave coagulation therapy.

The role of nasal carriage inStaphylococcus aureusburn wound colonization

Thermal injury destroys the physical skin barrier that normally prevents invasion of microorganisms. This and concomitant depression of local and systemic host cellular and humoral immune responses are important factors that contribute to colonization and infection of the burn wound. One of the most common burn wound pathogens is Staphylococcus aureus. Staphylococcus aureus is both a human commensal and a frequent cause of infections leading to mild to life-threatening diseases. Despite a variety of infection control measures, for example patient cohorting and contact precaution at burn centres, S. aureus is still frequently encountered in burn wounds. Colonization with S. aureus has been associated with delayed wound healing, increased need for surgical interventions, and prolonged length of stay at burn centres. In this minireview, we focus on S. aureus nasal carriage in relation to S. aureus burn wound colonization and subsequent infection, and its impact on strategies for infection control.

Collagen Synthesis Is Suppressed in Dermal Fibroblasts by the Human Antimicrobial Peptide LL-37

LL-37 is a human cathelicidin antimicrobial peptide that is released in the skin after injury and acts to defend against infection and modulate the local cellular immune response. We observed in human dermal keloids that fibrosis was inversely related to the expression of cathelicidin and sought to determine how LL-37 influenced expression of types I and III collagen genes in dermal fibroblasts. At nano-molar concentrations, LL-37 inhibited baseline and transforming growth factor-beta-induced collagen expression. At these concentrations, LL-37 also induced phosphorylation of extracellular signal-regulated kinase (ERK) within 30 minutes. Activation of ERK, and the activation of a G-protein-dependent pathway, was essential for inhibition of collagen expression as pertussis toxin or an inhibitor of ERK blocked the inhibitory effects of LL-37. c-Jun N-terminal kinase and p38 mitogen-activated protein kinase inhibitors did not alter the effects of cathelicidin. Silencing of the Ets-1 reversed inhibitory effects of LL-37. Taken together, these findings show that LL-37 can directly act on dermal fibroblasts and may have antifibrotic action during the wound repair process.

Comparative studies of local antibody and cellular immune responses to influenza infection and vaccination with live attenuated reassortant influenza vaccine (LAIV) utilizing a mouse nasal-associated lymphoid tissue (NALT) separation method

The first and most significant barrier against influenza infection is the mucosal-associated lymphoid tissue of the upper airways and rodent nasopharyngeal-associated lymphoid tissue (NALT) is considered equivalent to the lymphoid tissue of human Valdryer's ring. This study is the first attempt to analyze and compare local and systemic cellular and antibody immune responses in NALT and spleen in a mouse model of experimental influenza infection and intranasal vaccination with LAIV (live attenuated reassortant influenza vaccine). It was shown that the vaccine strain completely inherited the ability to induce high-grade local antibody responses (secretory IgA + IgG + IgM), local cellular lymphoproliferative activity, CD4 +, CD8 + and CD19 + lymphocyte and cytokine production responses from the virulent parental strain but it had less capacity to stimulate production of serum IgG, accumulation of CD8 + cells and IFN-γ production in the spleen. Primary non-complicated influenza infection and primary vaccination were accompanied by a short-term (24 h) increase in the levels of lymphocyte apoptosis in both NALT and spleen. However, experimental data indicated that vaccination with LAIV and uncomplicated forms of influenza infection did not influence immune system apoptosis following a secondary immune response.

Phagocytosis ofMycobacterium ulceransin the course of rifampicin and streptomycin chemotherapy in Buruli ulcer lesions

Infection with Mycobacterium ulcerans involves a devastating skin disease called Buruli ulcer (BU). Currently, dual therapy with rifampicin and streptomycin (R/S) for 8 weeks as well as surgery are the standard treatments. To elucidate the processes taking place in BU lesions in the course of chemotherapy we performed an in-depth histological analysis of lesions after 4 weeks of R/S treatment and compared results with findings in untreated lesions and lesions treated for 8 weeks. Tissue specimens were collected from patients who had no treatment and from patients after 4 and 8 weeks of R/S treatment. The main features evaluated were local immune responses, histopathological alterations and bacterial distribution. After 4 weeks of R/S treatment we observed a large proportion of mycobacteria inside macrophages, occasionally forming globus-like aggregations. While distinct bands of inflammatory leucocytes surrounded the necrotic core in an ulcer and early granuloma formation was apparent in the healthy-appearing margins, acute cellular infiltration covering the whole lesion had developed in a nodular lesion. In contrast, ulcerative lesions after 8 weeks of chemotherapy showed intra- and extracellular bacterial debris as well as the presence of extensive chronic infiltrates forming huge granulomas. R/S treatment of BU results in a rapid onset of local cellular immune responses associated with phagocytosis of the extracellular M. ulcerans. This may be related to declining levels of the macrolide toxin mycolactone in the tissue, thus leading to an enhanced chemotherapy-induced clearance of the infection.