Bronchus-Associated Lymphoid Tissue (BALT) and Survival in a Vaccine Mouse Model of Tularemia

Background: Francisella tularensis causes severe pulmonary disease, and nasal vaccination could be the ideal measure to effectively prevent it. Nevertheless, the efficacy of this type of vaccine is influenced by the lack of an effective mucosal adjuvant. Methodology/Principal Findings: Mice were immunized via the nasal route with lipopolysaccharide isolated from F. tularensis and neisserial recombinant PorB as an adjuvant candidate. Then, mice were challenged via the same route with the F. tularensis attenuated live vaccine strain (LVS). Mouse survival and analysis of a number of immune parameters were conducted following intranasal challenge. Vaccination induced a systemic antibody response and 70% of mice were protected from challenge as showed by their improved survival and weight regain. Lungs from mice recovering from infection presented prominent lymphoid aggregates in peribronchial and perivascular areas, consistent with the location of bronchus-associated lymphoid tissue (BALT). BALT areas contained proliferating B and T cells, germinal centers, T cell infiltrates, dendritic cells (DCs). We also observed local production of antibody generating cells and homeostatic chemokines in BALT areas. Conclusions: These data indicate that PorB might be an optimal adjuvant candidate for improving the protective effect of F. tularensis antigens. The presence of BALT induced after intranasal challenge in vaccinated mice might play a role in regulation of local immunity and long-term protection, but more work is needed to elucidate mechanisms that lead to its formation.

Immunohistochemical study of stromal and vascular components of tonsillar polyps: high endothelial venules as participants of the polyp`s lymphoid tissue

Tonsillar polyps are nonneoplastic lesions usually composed of variable amounts of lymphoid and vascular and connective tissues. All of them are generally assumed to be hamartomatous proliferations, but the profile of vascular and connective components has yet to be explored. The vascular system of the tonsils is complex and includes highly specialized structures (i.e., high endothelial venules (HEVs)) involved in lymphocyte homing into lymphoid tissues. In 14 tonsillar polyps and 26 control tonsils, an immunohistochemical study was performed using CD34 (blood vessels and HEVs), MECA-79 (HEVs), D2-40 (lymphatic vessels), Ki-67, collagens I and III, fibronectin, and tenascin-C. The polyps showed increased total lymphatic area, whereas the number of blood vessels and lymphatics and the blood vascular area did not differ significantly from those of control tonsils. Rare Ki-67+ endothelial cells were found. In the polyps, we detected, possibly for the first time, HEVs amid lymphoid tissue, and that the amount of the latter correlated positively with HEV density. The polyps also presented lesser amounts of fibronectin and collagens I and III than in normal tonsils, which were distributed in a disorganized fashion. Tenascin-C expression was uncommon in the polyps and control tonsils. Tonsillar polyps are composed of disorganized connective tissue and lymphatic channels which can be considered hamartomatous proliferations. However, the lymphoid component is possibly reactive due to its relationship with the HEVs. The highly differentiated phenotype of the HEVs and their complex biology are not in agreement with what would be expected for a component of hamartomatous nature.

Cutting edge: IL-7 regulates the peripheral pool of adult ROR gamma+ lymphoid tissue inducer cells.

During fetal life, CD4(+)CD3(-) lymphoid tissue inducer (LTi) cells are required for lymph node and Peyer's patch development in mice. In adult animals, CD4(+)CD3(-) cells are found in low numbers in lymphoid organs. Whether adult CD4(+)CD3(-) cells are LTi cells and are generated and maintained through cytokine signals has not been directly addressed. In this study we show that adult CD4(+)CD3(-) cells adoptively transferred into neonatal CXCR5(-/-) mice induced the formation of intestinal lymphoid tissues, demonstrating for the first time their bona fide LTi function. Increasing IL-7 availability in wild-type mice either by IL-7 transgene expression or treatment with IL-7/anti-IL-7 complexes increased adult LTi cell numbers through de novo generation from bone marrow cells and increased the survival and proliferation of LTi cells. Our observations demonstrate that adult CD4(+)lineage(-) cells are LTi cells and that the availability of IL-7 determines the size of the adult LTi cell pool.

Primary mucosa-associated lymphoid tissue lymphoma of the salivary glands: a multicenter Rare Cancer Network study.

Purpose: Involvement of salivary glands with mucosa-associated lymphoid tissue (MALT) lymphoma is rare. This retrospective study was performed to assess the clinical profile, treatment outcome, and prognostic factors of MALT lymphoma of the salivary glands.Methods and Materials: Thirteen member centers of the Rare Cancer Network from 10 countries participated, providing data on 63 patients. The median age was 58 years; 47 patients were female and 16 were male. The parotid glands were involved in 49 cases, submandibular in 15, and minor glands in 3. Multiple glands were involved in 9 patients. Staging was as follows: IE in 34, IIE in 12, IIIE in 2, and IV in 15 patients.Results: Surgery (S) alone was performed in 9, radiotherapy (RI) alone in 8, and chemotherapy (CT) alone in 4 patients. Forty-one patients received combined modality treatment (S + RT in 23, S + CT in 8, RT + CT in 4, and all three modalities in 6 patients). No active treatment was given in one case. After initial treatment there was no tumor in 57 patients and residual tumor in 5. Tumor progression was observed in 23 (36.5%) (local in 1, other salivary glands in 10, lymph nodes in 11, and elsewhere in 6). Five patients died of disease progression and the other 5 of other causes. The 5-year disease-free survival, disease-specific survival, and overall survival were 54.4%, 93.2%, and 81.7%, respectively. Factors influencing disease-free survival were use of RI, stage, and residual tumor (p < 0.01). Factors influencing disease-specific survival were stage, recurrence, and residual tumor (p < 0.01).Conclusions: To our knowledge, this report represents the largest series of MALT lymphomas of the salivary glands published to date. This disease may involve all salivary glands either initially or subsequently in 30% of patients. Recurrences may occur in up to 35% of patients at 5 years; however, survival is not affected. Radiotherapy is the only treatment modality that improves disease-free survival. (C) 2012 Elsevier Inc.

Restoration of lymphoid organ integrity through the interaction of lymphoid tissue-inducer cells with stroma of the T cell zone.

The generation of lymphoid microenvironments in early life depends on the interaction of lymphoid tissue-inducer cells with stromal lymphoid tissue-organizer cells. Whether this cellular interface stays operational in adult secondary lymphoid organs has remained elusive. We show here that during acute infection with lymphocytic choriomeningitis virus, antiviral cytotoxic T cells destroyed infected T cell zone stromal cells, which led to profound disruption of secondary lymphoid organ integrity. Furthermore, the ability of the host to respond to secondary antigens was lost. Restoration of the lymphoid microanatomy was dependent on the proliferative accumulation of lymphoid tissue-inducer cells in secondary lymphoid organs during the acute phase of infection and lymphotoxin alpha(1)beta(2) signaling. Thus, crosstalk between lymphoid tissue-inducer cells and stromal cells is reactivated in adults to maintain secondary lymphoid organ integrity and thereby contributes to the preservation of immunocompetence.

Ectopic lymphoid-organ development occurs through interleukin 7-mediated enhanced survival of lymphoid-tissue-inducer cells.

Development of Peyer's patches and lymph nodes requires the interaction between CD4+ CD3- IL-7Ralpha+ lymphoid-tissue inducer (LTi) and VCAM-1+ organizer cells. Here we showed that by promoting their survival, enhanced expression of interleukin-7 (IL-7) in transgenic mice resulted in accumulation of LTi cells. With increased IL-7 availability, de novo formation of VCAM-1+ Peyer's patch anlagen occurred along the entire fetal gut resulting in a 5-fold increase in Peyer's patch numbers. IL-7 overexpression also led to formation of multiple organized ectopic lymph nodes and cecal patches. After immunization, ectopic lymph nodes developed normal T cell-dependent B cell responses and germinal centers. Mice overexpressing IL-7 but lacking either RORgamma, a factor required for LTi cell generation, or lymphotoxin alpha1beta2 had neither Peyer's patches nor ectopic lymph nodes. Therefore, by controlling LTi cell numbers, IL-7 can regulate the formation of both normal and ectopic lymphoid organs.

Delivery of antigen to nasal-associated lymphoid tissue microfold cells through secretory IgA targeting local dendritic cells confers protective immunity.

BACKGROUND: Transmission of mucosal pathogens relies on their ability to bind to the surfaces of epithelial cells, to cross this thin barrier, and to gain access to target cells and tissues, leading to systemic infection. This implies that pathogen-specific immunity at mucosal sites is critical for the control of infectious agents using these routes to enter the body. Although mucosal delivery would ensure the best onset of protective immunity, most of the candidate vaccines are administered through the parenteral route. OBJECTIVE: The present study evaluates the feasibility of delivering the chemically bound p24gag (referred to as p24 in the text) HIV antigen through secretory IgA (SIgA) in nasal mucosae in mice. RESULTS: We show that SIgA interacts specifically with mucosal microfold cells present in the nasal-associated lymphoid tissue. p24-SIgA complexes are quickly taken up in the nasal cavity and selectively engulfed by mucosal dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-positive dendritic cells. Nasal immunization with p24-SIgA elicits both a strong humoral and cellular immune response against p24 at the systemic and mucosal levels. This ensures effective protection against intranasal challenge with recombinant vaccinia virus encoding p24. CONCLUSION: This study represents the first example that underscores the remarkable potential of SIgA to serve as a carrier for a protein antigen in a mucosal vaccine approach targeting the nasal environment.

Fatal outcome in bronchus-associated lymphoid tissue lymphoma

Linfomas primários do pulmão são raros. O tipo histológico mais freqüente é o linfoma do tecido linfóide associado ao brônquio. Este tipo de linfoma tem curso indolente e excelente resposta à terapia. Um terço dos casos é descoberto incidentalmente. Devido à raridade desta doença, no entanto, pouco se conhece sobre sua história natural em termos de disseminação e evolução. Neste relato, descrevemos o caso incomum de um homem de 61 anos que recusou o tratamento após diagnóstico de linfoma do tecido linfóide associado ao brônquio e, 2 anos após o diagnóstico, morreu por infiltração pulmonar maciça sem disseminação para outros órgãos.

Deletion of Epstein-Barr virus latent membrane protein 1 gene in United States and Brazilian Hodgkin's disease and reactive lymphoid tissue: High frequency of a 30-bp deletion

A 30-basepair (bp) deletion in the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene has been reported in nasopharyngeal carcinoma and EBV-associated malignant lymphomas. Prior studies have found the deletion in about 10% to 28% of cases of Hodgkin's disease (HD), particularly in cases with aggressive histology. We studied the prevalence of 30-bp LMP1 gene deletion in EBV-positive HD in the United States (US) (12 cases) and Brazil (26 cases) with comparison to reactive lymphoid tissues (21 cases) and HD without EBV-positive Reed-Sternberg cells (15 cases). We studied the status of the LMP1 gene by Southern blot hybridization of polymerase chain reaction (PCR) products obtained after amplification with primers spanning the site of the deletion. We also performed EBV typing, EBER1 in situ hybridization, and LMP1 protein immunohistochemistry. EBV was detected in 12/26 (46%) cases of HD from the US and 26/27 (96%) cases of Brazilian HD. The 30-bp LMP1 gene deletion was observed in 4/12 (33%) cases of EBV-positive HD from US, and 12/26 (46%) cases of Brazilian EBV-positive HD, including 3 cases of type B EBV, as compared with 12/21 (57%) reactive lymphoid tissues and 9/15 (60%) cases of EBV-negative HD. US and Brazilian HD showed a higher prevalence of the 30-bp LMP1 gene deletion, compared with studies of others. The unexpected finding of high incidence of 30-bp deletion in LMP1 gene in reactive lymphoid tissue and HD without EBV-positive Reed-Sternberg cells suggests that this deletion may not be relevant to HD pathogenesis in most cases. Copyright (C) 1997 by W.B. Saunders Company.

Genotyping of Epstein-Barr virus in Brazilian Burkitt's lymphoma and reactive lymphoid tissue - Type A with a high prevalence of deletions within the latent membrane protein gene

Both Epstein-Barr virus (EBV) types A and B are found in endemic Burkitt's lymphoma (BL) occurring in equatorial Africa. We studied 17 cases of Brazilian BL previously demonstrated to be EBV-positive to determine the EBV type as well as the presence of a characteristic 30 bp deletion within the 3' end of the latent membrane protein-1 (LMP-1) gene that may be important to the pathogenesis of several EBV-associated neoplasms. All case in which the age was known were children. We found type A EBV in 13 of 14 (93%) evaluable cases, and type B in one case. The LMP-1 deletion was found in 12 of 15 (80%) evaluable cases, including the one case of type B EBV, and a similar high prevalence (59%) of the deletion was detected in EBV-positive normal and reactive lymphoid tissues from individuals from the same geographic region. The high proportion of cases associated with type A EBV suggests that immunodeficiency is not an important factor in the pathogenesis of Brazilian BL, in contrast to endemic African BL. The presence of the LMP-1 deletion in a high prevalence in the normal population in this region is unexplained.

Naso-orbicular tissue necrosis by Streptococcus parasanguis in a patient with Fanconi anemia: Clinical and laboratory aspects

Fanconi anemia (FA) is a rare autosomal recessive disorder, characterized by pancytopenia and progressive hypoplasia of the bone marrow. A 23-year-old woman with FA showed severe pancytopenia and developed an abscess on the infraorbicular region on the right side of the face that progressed to phlegmon and caused tissue necrosis of the nostrils, nasal septum, nasal fossa, and posterior orbital region. Laboratory examination showed Streptococcus parasanguis as the etiologic agent of the phlegmon. Supportive treatment was recommended due to donor incompatibility for bone marrow transplant. The intraoral examination showed spontaneous gingival bleeding, edema of the interdental papillae, hematomas on the superior and inferior lips, bacterial and fungal infections, and adequate oral hygiene. The patient was treated with the administration of an antibiotic (imipenem), an antifungal (amphotericin B), and mouth washing with antiseptic solutions. Periodontal prophylaxis and orientation to and control of oral hygiene and diet were also used during the remission period. For functional and esthetic rehabilitation of the alar regions and nasal dorsum, an acrylic resin nasal prosthesis was made, supported by a spectacle frame.

Comparison of the larynx-associated lymphoid tissue in the false vocal cords and subglottis in pediatric autopsies

The aim this work was to compare the distribution of cellular phenotypes of the LF in the FVC to the ones in the subglottic region in pediatric autopsy, relating this distribution to age and different causes of death. We analyzed 60 larynges of newborns and children autopsied in the period from 1993 to 2003. The fragments were prepared in order to perform histochemical and immunohistochemical techniques. The morphological analysis showed cases that presented LF only in FVC (35%), LF only in the subglottic region (20%), lack of LF in FVC (30%) and lymphoid aggregates, which did not characterize an LF (15%). The cases of LF in the subglottic region were significantly younger compared to the ones that presented LF in the FVC (p = 0.017). The LF in the subglottic region was bigger than the LF in the FVC (p = 0.020). There was no significant difference between the cause of death and cellular phenotype for both FVC and the subglottic region. In conclusion, the cells that make up the LF in the FVC in newborns and children younger than one year have functional characteristics similar to LF cells in the subglottic region, suggesting that there are similarities with LALT. (c) 2012 Elsevier GmbH. All rights reserved.

Global lymphoid tissue remodeling during a viral infection is orchestrated by a B cell-lymphotoxin-dependent pathway

Adaptive immune responses are characterized by substantial restructuring of secondary lymphoid organs. The molecular and cellular factors responsible for virus-induced lymphoid remodeling are not well known to date. Here we applied optical projection tomography, a mesoscopic imaging technique, for a global analysis of the entire 3-dimensional structure of mouse peripheral lymph nodes (PLNs), focusing on B-cell areas and high endothelial venule (HEV) networks. Structural homeostasis of PLNs was characterized by a strict correlation between total PLN volume, B-cell volume, B-cell follicle number, and HEV length. After infection with lymphocytic choriomeningitis virus, we observed a substantial, lymphotoxin (LT) beta-receptor-dependent reorganization of the PLN microarchitecture, in which an initial B-cell influx was followed by 3-fold increases in PLN volume and HEV network length on day 8 after infection. Adoptive transfer experiments revealed that virus-induced PLN and HEV network remodeling required LTalpha(1)beta(2)-expressing B cells, whereas the inhibition of vascular endothelial growth factor-A signaling pathways had no significant effect on PLN expansion. In summary, lymphocytic choriomeningitis virus-induced PLN growth depends on a vascular endothelial growth factor-A-independent, LT- and B cell-dependent morphogenic pathway, as revealed by an in-depth mesoscopic analysis of the global PLN structure.

Aseptic tissue necrosis and chronic inflammation after irrigation of penetrating hand wounds using Octenisept®

Penetrating hand wounds are common and these are managed by thorough debridement. However, stab wounds without evidence of divided structures are often treated with irrigation using antiseptic substances, antibiotic therapy, and immobilization. Octenisept® (Schülke & Mayr Ltd) is a widely used antiseptic agent for disinfection of acute or chronic wounds. It has a broad spectrum of antiseptic efficacy and has become an antiseptic of first choice in many hospitals. Within a few months, four patients presented to us with chronic inflammation and severe tissue necrosis after irrigation of penetrating hand wounds with Octenisept®. Repeated surgery and debridement was required in all patients. Wound healing was prolonged and patients had persisting oedema. Penetrating hand wounds must not be irrigated with Octenisept®.