Lav/HTLV-III Neutralizing Antibodies in the Sera of Patients with Aids, Lymphadenopathy Syndrome and Asymptomatic Seropositive Individuals

Serum samples which had previously been found positive for LAV/HTLV-III antibodies by the ELISA test and then confirmed by radioimmunoassay (Western blot) were tested for the presence of neutralizing antibodies. No neutralizing activity was found in the sera of a group of patients with the clinical diagnosis of AIDS. However in patients with LAS and other related pathologic conditions the percentage of sera positive for neutralizing antibodies was 27 % and 55 % respectively. At least 50 % of the sera from seropositive asymptomatic individuals had neutralizing activity but with the exception of the haemophiliac group the mean titre was much lower than that of LAS patients. No relationship was found between the neutralizing titre and the antibody specificity detected by Western blot analysis for p41 and p120.

Possible relationship between fibrosis of IgG4-related thymitis and the profibrotic cytokines, transforming growth factor beta 1, interleukin 1 beta and interferon gamma: a case report

BACKGROUND

IgG4-related disease often forms a mass and the affected lesion is clinically removed because the mass cannot be differentiated from a neoplasm. Affected lesions commonly occur in the pancreas, hepatobiliary tract, kidney, and retroperitoneum. However, the lesion rarely occurs in the thymus. A histological worldwide consensus of IgG4-related disease proposed that pathological diagnosis of IgG4-related disease should meet more than two of three major features: 1) dense lymphoplasmacytic infiltration with greater than 40% IgG4+/IgG+ plasma cells, 2) storiform fibrosis; and 3) obliterative phlebitis. Currently, fibrosis of IgG4-related disease is thought to be induced by profibrotic cytokines such as transforming growth factor beta 1 (TGFB1), interleukin 1 beta (IL1B) and interferon gamma (IFNG), which are secreted by regulatory T cells (Tregs) and CD4-positive cytotoxic T cells. However, it is unclear whether profibrotic cytokines are associated with the fibrosis seen in IgG4-related thymitis. Here we examined whether cytokines in the mass were increased compared with those in the surrounding thymus, and whether Tregs were present in the mass, using reverse transcription absolute quantitative polymerase chain reaction (RT-ab-qPCR) and immunohistochemistry.

CASE PRESENTATION

A 70-year-old Japanese man contracted IgG4-letated thymitis. Histological and immunohistochemical analyses demonstrated his mass had massive fibrosis with a focally storiform pattern and lymphoplasmacytic infiltration with 40% IgG4+/IgG+ plasma cells, but not obliterative phlebitis. The mass was surrounded by atrophic thymus. We diagnosed the mass as IgG4-related thymitis. Immunohistochemically, Tregs were scattered throughout the mass. RT-ab-qPCR showed that messenger RNA expressions of TGFB1, IL1B and IFNG in the mass were 270-, 158- and 5.5- fold higher than in the surrounding thymus. His serum IgG4 level after surgery was within the normal range (83.4 mg/dl soon after surgery, 89.3 mg/dl 2 weeks after surgery).

CONCLUSIONS

Our results suggested the profibrotic cytokines TGFB1, IL1B and IFNG induce fibrosis and that Tregs might produce some of these cytokines in IgG4-related thymitis as well as in the other affected lesions of IgG4-related disease.

Nodular lymphoid hyperplasia: A marker of low-grade inflammation in irritable bowel syndrome?

AIM

To evaluate the prevalence of nodular lymphoid hyperplasia (NLH) in adult patients undergoing colonoscopy and its association with known diseases.

METHODS

We selected all cases showing NLH at colonoscopy in a three-year timeframe, and stratified them into symptomatic patients with irritable bowel syndrome (IBS)-type symptoms or suspected inflammatory bowel disease (IBD), and asymptomatic individuals undergoing endoscopy for colorectal cancer screening. Data collection included medical history and final diagnosis. As controls, we considered all colonoscopies performed for the aforementioned indications during the same period.

RESULTS

One thousand and one hundred fifty colonoscopies were selected. NLH was rare in asymptomatic individuals (only 3%), while it was significantly more prevalent in symptomatic cases (32%). Among organic conditions associated with NLH, the most frequent was IBD, followed by infections and diverticular disease. Interestingly, 31% of IBS patients presented diffuse colonic NLH. NLH cases shared some distinctive clinical features among IBS patients: they were younger, more often female, and had a higher frequency of abdominal pain, bloating, diarrhoea, unspecific inflammation, self-reported lactose intolerance and metal contact dermatitis.

CONCLUSION

About 1/3 of patients with IBS-type symptoms or suspected IBD presented diffuse colonic NLH, which could be a marker of low-grade inflammation in a conspicuous subset of IBS patients.

[Presence of lactoferrin (LF) in lymphocutaneous sporotrichosis. Yeast-bound antimicrobial peptide]

Sporotrichosis is a common subcutaneous mycosis in Latin America, produced by dimorphic fungi belong to Sporothrix schenckii complex of cryptic species. Infection is acquired by traumatic inoculation with contaminated organic material. Host immune response includes polymorphonuclear neutrophils chemotaxis and release of granular components. Lactoferrin is a protein member of the transferrin family of iron-binding proteins, present inside polymorphonuclear granular structure, and has been reported to affect growth and development of infectious agents, including fungal organisms. Nevertheless, lactoferrin expression in sporotrichosis infections has not been reported yet.

OBJECTIVE

To determine the expression of lactoferrin using immunohistochemical staining in sporotrichosis human infection.

MATERIAL AND METHODS

The dermatology department's files during a period of five years were reviewed; cases with a diagnosis of sporotrichosis were selected and lactoferrin immunostaining was performed when enough biological material was available.

RESULTS

Three cases with a diagnosis of sporotrichosis and adequate biological material on paraffin block were identified. In all cases, lactoferrin immunostaining was positive around yeast cell.

Intrathoracic Involvements of Immunoglobulin G4-Related Sclerosing Disease

To investigate clinical and radiological features of IgG4-related disease (IgG4-RD) patients with intrathoracic involvement. A prospective cohort study was performed and IgG4-RD patients were enrolled from January 2011 to March 2015 in Peking Union Medical College Hospital, in which the clinical and radiological characteristics of IgG4-RD patients with intrathoracic involvement were summarized. Out of total 248 cases with IgG4-RD, 87 cases had intrathoracic lesions, including 58 male cases and 29 female cases, with average age of 54.19 ± 13.80 years. Hilar and mediastinal lymphadenopathy were the most common manifestations of IgG4-related intrathoracic disease, accounting for 52.9% (46/87). Other imaging findings of pulmonary disease included: solid nodular (25.3%), round-shaped ground-glass opacities (9.2%), alveolar-interstitial type (20.7%), bronchovascular type (23.0%), pleural effusion (4.6%), and pleural nodules or thickening (16.1%). Only 27 patients presented with respiratory symptoms, including cough, breathless, chest pain, and asthma. Compared with patients without intrathoracic disease, IgG4-related intrathoracic disease had higher IgG4 and C-reactive protein level, and higher incidence of allergy, fever, and multi-organ involvement. Most of lung interstitial disease, mediastinal mass, and bronchial thickening were sensitive to corticosteroid and immunosuppressant therapy, while 36.3% (8/22) of solitary nodular lesions were unresponsive to treatment. Eight patients were on no treatment, with 5 cases remained stable, 2 patients improved spontaneously, and 1 patient was lost follow-up. Intrathoracic lesions are not rare in patients with IgG4-RD, involving bronchial thickening, nodules, ground glass opacity, pleural thickening/effusion, lymphadenopathy, etc. Efficacy of corticosteroid and immunosuppressant therapy were noted in most of patients with lung interstitial disease, mediastinal mass, and bronchial thickening.

IgG4-related prostatitis progressed from localized IgG4-related lymphadenopathy

Immunoglobulin G4-related disease (IgG4-RD) is a recently described inflammatory disease involving multiple organs. Prostate involvement with IgG4-RD is very rare. In this report, we describe a case of IgG4-related prostatitis progressed from localized IgG4-related lymphadenopathy. This patient was present with urine retention symptoms. MRI and CT examination revealed the prostatic enlargement and the multiple lymphadenopathy. Serum IgG4 levels were elevated. Prostatic tissue samples resected both this time and less than 1 year earlier showed the same histological type of prostatitis with histopathologic and immunohistochemical findings characteristic of IgG4-RD. The right submandibular lymph nodes excised 2 years earlier were eventually proven to be follicular hyperplasia-type IgG4-related lymphadenopathy. This is the first case of IgG4-RD that began as localized IgG4-related lymphadenopathy and progressed into a systemic disease involving prostate and multiple lymph nodes. This patient showed a good response to steroid therapy. This leads us to advocate a novel pathogenesis of prostatitis, and a novel therapeutic approach against prostatitis. Pathologists and urologists should consider this disease entity in the patients with elevated serum IgG4 levels and the symptoms of prostatic hyperplasia to avoid ineffective medical or unnecessary surgical treatment.

IgG4-Related Disease Presenting as a Solitary Neck Mass

IgG4-related disease is a newly recognized entity associated with autoimmune conditions involving almost every organ system. It is characterized by elevated serum IgG4 as well as mass like tissue infiltration by IgG4-positive plasma cells. Imaging findings are nonspecific, vary depending on the site of disease, and include mass like enlargement of the salivary or lacrimal glands and enlarged lymph nodes. Radiographic findings often mimic malignancy, necessitating tissue sampling to confirm the diagnosis. Distinguishing IgG4-related disease from malignancy is important as IgG4 responds well to steroids and conservative management.

Paradoxical effects of all-trans-retinoic acid on lupus-like disease in the MRL/lpr mouse model

Roles of all-trans-retinoic acid (tRA), a metabolite of vitamin A (VA), in both tolerogenic and immunogenic responses are documented. However, how tRA affects the development of systemic autoimmunity is poorly understood. Here we demonstrate that tRA have paradoxical effects on the development of autoimmune lupus in the MRL/lpr mouse model. We administered, orally, tRA or VA mixed with 10% of tRA (referred to as VARA) to female mice starting from 6 weeks of age. At this age, the mice do not exhibit overt clinical signs of lupus. However, the immunogenic environment preceding disease onset has been established as evidenced by an increase of total IgM/IgG in the plasma and expansion of lymphocytes and dendritic cells in secondary lymphoid organs. After 8 weeks of tRA, but not VARA treatment, significantly higher pathological scores in the skin, brain and lung were observed. These were accompanied by a marked increase in B-cell responses that included autoantibody production and enhanced expression of plasma cell-promoting cytokines. Paradoxically, the number of lymphocytes in the mesenteric lymph node decreased with tRA that led to significantly reduced lymphadenopathy. In addition, tRA differentially affected renal pathology, increasing leukocyte infiltration of renal tubulointerstitium while restoring the size of glomeruli in the kidney cortex. In contrast, minimal induction of inflammation with tRA in the absence of an immunogenic environment in the control mice was observed. Altogether, our results suggest that under a predisposed immunogenic environment in autoimmune lupus, tRA may decrease inflammation in some organs while generating more severe disease in others.

[Clinicopathologic characteristics of IgG4-related disease in orbital and periorbital tissue]

OBJECTIVE

To study the clinicopathologic characteristics of IgG4-related disease in the orbital and periorbital tissue.

METHODS

The clinical manifestations and pathologic features of 17 cases of IgG4-related disease affecting the orbital and periorbital tissue encountered during the period from 2012 to 2013 were studied.

RESULTS

There were 9 male patients and 8 female patients. The age of patients ranged from 11 to 71 years (mean = 48.5 years). The main clinical manifestation was swelling of the eyelids: bilateral in 11 patients and unilateral in 6 patients. The duration of disease ranged from 5 months to 7 years (more than 2 years in 13 cases). Six patients had history of allergic disorders. In addition to orbital/periorbital involvement, the disease also affected salivary gland, lymph node, lung and kidney. The disease relapsed in 9 patients. Amongst the 8 patients treated with steroids, 5 of them achieved complete remission and the remaining 3 patients had partial remission. The IgG4 level of the 17 cases ranged from 1.49 to 14.88 g/L. Histologic examination showed pseudolymphoma pattern in 8 cases, mixed pattern in 8 cases and sclerotic pattern in 1 case. There were various degrees of lymphoplasmacytic infiltrates (with lymphoid follicle formation) and stromal fibrosis. Classical obliterative phlebitis was absent. Tissue eosinophilia was demonstrated in the 17 cases studied. Immunohistochemical study showed the presence of more than 50 IgG4-positive plasma cells per high-power field, with IgG4/IgG plasma cells ratio more than 40%.

CONCLUSION

There are characteristic clinical manifestations, pathologic features and laboratory findings in orbital and periorbital IgG4-related disease. Thorough understanding is important in arriving at a correct diagnosis.

[Fever and lymphadenopathy: acute toxoplasmosis in an immunocompetent patient]

Toxoplasmosis is an infectious disease caused by the intracellular parasite Toxoplasma gondii. In Switzerland about a third of the population has antibodies against this pathogen and has thus already been in contact with the parasite or has contracted the disease. Immunocompetent patients are usually asymptomatic (80-90%) during primary infection. The most common symptom is neck or occipital lymphadenopathy. Serology is the diagnostic gold standard in immunocompetent individuals. The presence of IgM antibodies is however not sufficient to make a definite diagnosis of acute toxoplasmosis. Distinction between acute and chronic toxoplasmosis requires additional serological tests (IgG avidity test). If required, the most used and probably most effective treatment is the combination of pyrimethamine and sulfadiazine, with folinic acid.

Recurrent lymphangitic cellulitis syndrome: A quintessential example of an immunocompromised district

Recurrent lymphangitic cellulitis syndrome (RLCS) occurs when a disordered lymphatic system renders a leg vulnerable to recurrent infection. The underlying immunologic defect is the result of accidental or iatrogenic penetrating wounds on the medial aspect of the thigh or lower limb overlying the greater saphenous vein, because the primary lymphatic drainage vessels are adjacent to this structure. Cracking/fissuring of the skin associated with chronic fungal infection of the feet ("athlete's foot"), most commonly mixed bacterial/fungal interdigital involvement, provides a portal of entry for opportunistic organisms. Bacteria and their products are cleared more slowly in the lymphatic-disrupted and therefore immunologically impaired limb, producing broad areas of dermatitis and around the scars quite distinct from other forms of superficial infection. This rarely develop in otherwise normal limbs. The dermatitis of RLCS and its systemic effects clear with antibiotics but recur intermittently until the tinea pedis is eradicated. The contralateral limb with normal lymphatic structures never develops clinical evidence of infection even though bilateral tinea infection is almost always present. This confirms the central role of an anatomically induced immunocompromised district (ICD) in this syndrome.

Pulmonary arterial hypertension associated with IgG4-related disease

A 22-year-old woman with generalized lymphadenopathy and symmetrical swelling of the lacrimal and submandibular glands was diagnosed with IgG4-related disease. Biopsy specimens of the lips, lymph nodes, gastrointestinal tract and bronchus showed IgG4-positive plasma cell infiltration. Echocardiography and right heart catheterization revealed a high mean pulmonary arterial pressure. The patient was treated with 50 mg of prednisolone daily and rapidly improved. This is the first reported case of pulmonary arterial hypertension associated with IgG4-related disease.

Clinical significance of complement as a biomarker of disease activity in 4 cases of IgG4-related disease with retroperitoneal fibrosis

Hypocomplementaemia is frequently observed in IgG4-related diseases, however the clinical significance is unclear. We describe herein the clinical courses of 4 patients with IgG4-related disease with hypocomplementaemia. Our cases showed autoimmune pancreatitis, retroperitoneal fibrosis, Mikulicz's disease, interstitial lung disease, lymphadenopathy and mesenteric fibrosis around the aorta. A decrease in serum complement preceded deterioration of the disease and clinical improvement was observed in accordance with normalisation of serum complement. These clinical courses suggest that serum complement is a biomarker of the disease activity.

Case of autoimmune hepatitis with markedly enlarged hepatoduodenal ligament lymph nodes

Autoimmune hepatitis (AIH) is a necroinflammatory liver disease of unknown etiology. The disease is characterized histologically by interface hepatitis, biochemically by increased aspartate aminotransferase and alanine aminotransferase levels, and serologically by increased autoantibodies and immunoglobulin G levels. Here we discuss AIH in a previously healthy 37-year-old male with highly elevated serum levels of soluble interleukin-2 receptor and markedly enlarged hepatoduodenal ligament lymph nodes (HLLNs, diameter, 50 mm). Based on these observations, the differential diagnoses were AIH, lymphoma, or Castleman’s disease. Liver biopsy revealed the features of interface hepatitis without bridging fibrosis along with plasma cell infiltration which is the typical characteristics of acute AIH. Lymph node biopsy revealed lymphoid follicles with inflammatory lymphocytic infiltration; immunohistochemical examination excluded the presence of lymphoma cells. Thereafter, he was administered corticosteroid therapy: after 2 mo, the enlarged liver reached an almost normal size and the enlarged HLLNs reduced in size. We could not find AIH cases with such enlarged lymph nodes (diameter, 50 mm) in our literature review. Hence, we speculate that markedly enlarged lymph nodes observed in our patient may be caused by a highly activated, humoral immune response in AIH.

Accumulation of tissue macrophages and depletion of resident macrophages in the diabetic thymus in response to hyperglycemia-induced thymocyte apoptosis

AIMS

We investigated the dynamics and morphology of thymus macrophages in response to thymus involution caused by hyperglycemia. Thymus is an organ affected early and dramatically after the onset of diabetes, losing most of the thymocyte populations but diabetes's impact on the components of the thymus stroma is largely unknown.

METHODS

Rats were injected with streptozotocin and thymus weight, body weight, and glycemia were measured at various time points. The dynamics and morphology of macrophages in the diabetic thymus were investigated by histology, immunohistochemistry, qPCR, electron microscopy and flow cytometry.

RESULTS

In hyperglycemic animals the involuting thymus is gradually infiltrated by tissue macrophages (ED1-positive) and depleted of resident macrophages (ED2-positive). While ED1 positive macrophages are scattered in both cortex and medulla the ED2 positive ones are limited to the cortex and cortico-medullary junction. CD4+CD11b+macrophages also accumulate. The TUNEL reaction that detects the degradation of the DNA from apoptotic thymocytes in the macrophages is enhanced. The thymic macrophages enlarge and accumulate lipid vacuoles and apoptotic bodies. qPCR measurements of the expression of macrophage markers showed a persistent increase in the diabetic thymus after the injection of streptozotocin.

CONCLUSIONS

Thymus involutes rapidly and persistently after the onset of hyperglycemia because of the elevated apoptosis in the thymocytes. Tissue macrophages accumulate in the thymus and the resident macrophages decrease. This results in an overall increase in macrophage activity in the diabetic thymus in response to the elevated apoptosis of thymocytes produced by hyperglycemia.

The endometrial lymphatic vasculature: function and dysfunction

The endometrium has a complex and dynamic blood and lymphatic vasculature which undergoes regular cycles of growth and breakdown. While we now have a detailed picture of the endometrial blood vasculature, our understanding of the lymphatic vasculature in the endometrium is limited. Recent studies have illustrated that the endometrium contains a population of lymphatic vessels with restricted distribution in the functional layer relative to the basal layer. The mechanisms responsible for this restricted distribution and the consequences for endometrial function are not known. This review will summarise our current understanding of endometrial lymphatics, including the mechanisms regulating their growth and function. The potential contribution of lymphatic vessels and lymphangiogenic growth factors to various endometrial disorders will be discussed.

Management of immune-related adverse events and kinetics of response with ipilimumab

Monoclonal antibodies directed against the immune checkpoint protein cytotoxic T-lymphocyte antigen-4 (CTLA-4; CD152)-ipilimumab and tremelimumab-have been investigated in metastatic melanoma and other cancers and have shown promising results. Recently, ipilimumab was approved by the US Food and Drug Administration for the treatment of metastatic melanoma. We review the literature on managing the adverse effects and kinetics of tumor regression with ipilimumab and provide guidelines on their management. During treatment with these antibodies, a unique set of adverse effects may occur, called immune-related adverse events (irAEs). These include rashes, which may rarely progress to life-threatening toxic epidermal necrolysis, and colitis, characterized by a mild to moderate, but occasionally also severe and persistent diarrhea. Hypophysitis, hepatitis, pancreatitis, iridocyclitis, lymphadenopathy, neuropathies, and nephritis have also been reported with ipilimumab. Early recognition of irAEs and initiation of treatment are critical to reduce the risk of sequelae. Interestingly, irAEs correlated with treatment response in some studies. Unique kinetics of response have been observed with CTLA-4 blockade with at least four patterns: (1) response in baseline lesions by week 12, with no new lesions seen; (2) stable disease, followed by a slow, steady decline in total tumor burden; (3) regression of tumor after initial increase in total tumor burden; and (4) reduction in total tumor burden during or after the appearance of new lesion(s) after week 12. We provide a detailed description of irAEs and recommendations for practicing oncologists who are managing them, along with the unusual kinetics of response associated with ipilimumab therapy.

A novel method to allow noninvasive, longitudinal imaging of the murine immune system in vivo

In vivo imaging has revolutionized understanding of the spatiotemporal complexity that subserves the generation of successful effector and regulatory immune responses. Until now, invasive surgery has been required for microscopic access to lymph nodes (LNs), making repeated imaging of the same animal impractical and potentially affecting lymphocyte behavior. To allow longitudinal in vivo imaging, we conceived the novel approach of transplanting LNs into the mouse ear pinna. Transplanted LNs maintain the structural and cellular organization of conventional secondary lymphoid organs. They participate in lymphocyte recirculation and exhibit the capacity to receive and respond to local antigenic challenge. The same LN could be repeatedly imaged through time without the requirement for surgical exposure, and the dynamic behavior of the cells within the transplanted LN could be characterized. Crucially, the use of blood vessels as fiducial markers also allowed precise re-registration of the same regions for longitudinal imaging. Thus, we provide the first demonstration of a method for repeated, noninvasive, in vivo imaging of lymphocyte behavior.

IgG4-related sclerosing disease, an emerging entity: a review of a multi-system disease

Immunoglobulin G4-related systemic disease (IgG4-RSD) is a recently defined emerging entity characterized by a diffuse or mass forming inflammatory reaction rich in IgG4-positive plasma cells associated with fibrosclerosis and obliterative phlebitis. IgG4-RSD usually affects middle aged and elderly patients, with a male predominance. It is associated with an elevated serum titer of IgG4, which acts as a marker for this recently characterized entity. The prototype is IgG4-related sclerosing pancreatitis or autoimmune pancreatitis (AIP). Other common sites of involvement are the hepatobiliary tract, salivary gland, orbit, and lymph node, however practically any organ can be involved, including upper aerodigestive tract, lung, aorta, mediastinum, retroperitoneum, soft tissue, skin, central nervous system, breast, kidney, and prostate. Fever or constitutional symptoms usually do not comprise part of the clinical picture. Laboratory findings detected include raised serum globulin, IgG and IgG4. An association with autoantibody detection (such as antinuclear antibodies and rheumatoid factor) is seen in some cases. Steroid therapy comprises the mainstay of treatment. Disease progression with involvement of multiple organ-sites may be encountered in a subset of cases and may follow a relapsing-remitting course. The principal histopathologic findings in several extranodal sites include lymphoplasmacytic infiltration, lymphoid follicle formation, sclerosis and obliterative phlebitis, along with atrophy and destruction of tissues. Immunohistochemical staining shows increased IgG4+ cells in the involved tissues (>50 per high-power field, with IgG4/IgG ratio >40%). IgG4-RSD may potentially be rarely associated with the development of lymphoma and carcinoma. However, the nature and pathogenesis of IgG4-RSD are yet to be fully elucidated and provide immense scope for further studies.

IgG4-related tubulointerstitial nephritis and lymphadenopathy after therapy for malignant lymphoma

We report a middle-aged Japanese man who had a past history of malignant lymphoma with tubulointerstitial nephritis (TIN) presenting a high serum immunoglobulin G4 (IgG4) concentration and bilateral kidney enlargement and swelling of many lymph nodes. Although lymph node biopsy was not evident of a recurrence of lymphoma, kidney biopsy showed prominent infiltration of IgG4-positive plasma cells in a tubulointerstitial lesion but not in glomeruli. We made a diagnosis of IgG4-related TIN and lymphadenopathy; administration of oral prednisolone improved his physical and laboratory parameters. This is the first report of a case of IgG4-related TIN and lymphadenopathy after therapy for malignant lymphoma.

Systemic autoimmunity and lymphoproliferation are associated with excess IL-7 and inhibited by IL-7Rα blockade

Lupus is characterized by disturbances in lymphocyte homeostasis, as demonstrated by the marked accumulation of activated/memory T cells. Here, we provide evidence that proliferation of the CD8⁺ precursors for the accumulating CD4^–CD8^– T cells in MRL-Fas^lpr lupus-predisposed mice is, in part, driven by commensal antigens. The ensuing lymphadenopathy is associated with increased production of IL-7 due to expansion of fibroblastic reticular cells, the primary source of this cytokine. The excess IL-7 is not, however, consumed by CD4^–CD8^– T cells due to permanent down-regulation of IL-7Rα (CD127), but instead supports proliferation of autoreactive T cells and progression of autoimmunity. Accordingly, IL-7R blockade reduced T cell activation and autoimmune manifestations even when applied at advanced disease stage. These findings indicate that an imbalance favoring production over consumption of IL-7 may contribute to systemic autoimmunity, and correction of this imbalance may be a novel therapeutic approach in lymphoproliferative and autoimmune syndromes.

A case of IgG4-related disease with features of Mikulicz's disease, and retroperitoneal fibrosis and lymphadenopathy mimicking Castleman's disease

A 51-year-old man developed painless enlargement of the bilateral submandibular and lacrimal glands without xerostomia or xerophthalmia in the absence of autoantibodies to SS-A (Ro) and SS-B (La). In a few years, he developed generalized lymphadenopathy, with markedly elevated serum IgG4, and a computed tomography scan revealed soft-tissue-density lesions around the abdominal aorta, a finding consistent with retroperitoneal fibrosis. Biopsy of the cervical lymph node showed an expansion of the interfollicular area by heavily infiltrating plasma cells, consistent with multicentric Castleman's disease. Immunohistochemical analysis revealed that the IgG4-positive/IgG-positive plasma cell ratio was 80%, leading us to a single diagnosis of IgG4-related disease. High-dose corticosteroid treatment resulted in prompt resolution of the physical, serological, and imaging abnormalities. Although IgG4-related disease can mimic multicentric Castleman's disease, as in our patient, the two diseases have effective but distinct treatments, and thus measurement of serum IgG4 levels and specific immunohistochemical analysis for determining the IgG4-positive/IgG-positive plasma cell ratio are recommended if IgG4-related disease is suspected.

[Immunocompromised HIV patient with lymphadenopathy and fever]

The case of a immunocompromised HIV patient with fever and lymphadenopathy discussed in an anatomo-pathological round. This complex clinical case was used as an opportunity to discuss the broad differential diagnosis of fever in an immunocompromized individual with multiples lymphadenopathies. Clinical reasoning leading to the probable diagnosis based on clinical, biological and radiological informations is not only a difficult task for the speaker but also a rich source of learning opportunities for our medical community.

[IgG4-related disease-the diagnostic confusion and how to avoid it]

Since Hamano et al. have first reported serum IgG4 elevation in sclerosing pancreatitis in 2001, various systemic disorders have been reported to be related to elavated IgG4, and many names have been proposed from the point of view of the systemic condition. Despite similarities in the organs damaged in IgG4-related Mikulicz's disease and Sjögren's syndrome, there are marked clinical and pathological differences between the two entities. IgG4-related Mikulicz's disease and Küttner's tumor are related diseases and complete differentiation is very difficult. The majority of cases diagnosed with autoimmune pancreatitis in Japan are IgG4-related sclerosing pancreatitis, and it should be recognized that this is distinct from the western type. There is a likelihood that cases once diagnose as Castleman's disease that showed good responsiveness to glucocorticoid treatment may have been IgG4-related lymphadenopathy, and should be re-assessed in light of recent findings. Diagnosis of IgG4-related disease is defined by both 1) Elevated serum IgG4 (>135 mg/dl) and 2) Histopathological features including lymphocyte and IgG4(+) plasma cell infiltration (IgG4(+) plasma cells/IgG(+) plasma cells >50% on a highly-magnified slide checked in five points), however differential diagnosis from other distinct disorders, such as sarcoidosis, Castleman's disease, Wegener's granulomatosis, lymphoma, cancer, and other existing conditions is necessary. To avoid diagnostic confusion, simpler and more scientific names should be used where disease-specific pathogenesis or markers have been ascertained.

Lymphadenopathy and expression of nodal mast cells and eosinophils in the myiasis by human bot fly

Wistar rats (Rattus norvegicus) infested with Dermatobia hominis (L. Jr., 1781) had their axillary lymph nodes removed and histopathologically processed. Follicular hyperplasia in the germinal center was noted from 2 d postinfestation (dpi), exhibiting a high number of centerblasts, mitotic and apoptotic cells, and a thin parafollicular area. The paracortex showed hyperplasia rich in dendritic cells, immunoblasts, and endothelial venules, with diapedesis seen from 4 dpi onward. Hyperplasia of the medullar sinus also was first observed at this point, as well as dilated lymphatic sinus, lymph, macrophages, neutrophils, mast cells, and eosinophils. Medullar strings were expanded and filled with immunoblasts, mitotic cells, and plasmocytes. Lymphadenitis was not observed. The expression of mast cells was similar for both myiasis-affected and control rats but increased significantly (mastocytosis) at 7 and 15 d postlarval emergence (dple). Eosinophilia was observed at 4, 10, 15, 20, and 28 dpi as well as at 2, 7, and 15 dple, particularly on the last three observations of dpi and the earliest dple. This experimental approach allowed progressive tissue reactions in the lymph nodes to be monitored during myiasis, particularly those involving mast cells and eosinophils. These reactions abated and complete repair was observed at 60 dple.

Intracranial Hodgkin's lymphoma in an HIV positive patient

Intracranial Hodgkin's lymphoma (ICHL) in the HIV positive population is a rarely reported event with only three prior cases reported in the literature. In these prior reports, the outcome of the patients was uncertain or very poor. We report here the case of an HIV seropositive patient with an isolated intracranial recurrence of Hodgkin's Lymphoma (HL) who achieved long-term control of his cranial disease and continues to have a high performance status more than 3 years following treatment.

The clinical spectrum of IgM-related amyloidosis: a French nationwide retrospective study of 72 patients

Immunoglobulin M (IgM)-related amyloidosis remains a rare and little-known complication of monoclonal IgM-associated disorders. We sought to determine the clinical and laboratory presentation, response to treatment, and outcome of patients with IgM-related amyloidosis in the era of new therapeutic approaches. We conducted a retrospective study in 29 French centers to identify patients with monoclonal IgM and biopsy-proven amyloidosis; we reviewed patients' records and collected relevant clinical and laboratory data. We identified 72 patients with IgM-related amyloidosis. Systemic primary amyloidosis (AL) was present in 64, peritumoral AL in 5, and systemic secondary amyloidosis (AA) in 3 patients. A peculiar pattern of relatively frequent lymph node (31%) and lung (17%) involvement was noted in patients with systemic AL amyloidosis. Response to alkylating agents was poor, with a hematologic response in 37%, a complete remission in 0%, and an organ response in 21%. Response to hematopoietic stem cell transplantation showed a hematologic response in 100% with complete remission in 75% and an organ response in 75%. Purine analogs and rituximab induced a hematologic response in 73% and 60%, respectively, with complete remission in 9% and 0% and an organ response in 55% and 0%, respectively. In multivariate analysis, prognostic factors for survival were serum albumin level < or =3.5 g/dL (p = 0.018) and heart involvement (p = 0.0034). Further prospective studies are needed in patients with IgM-related amyloidosis, with special emphasis on treatment options: hematopoietic stem cell transplantation and purine analogs could represent the most effective therapies. The identification of adverse prognostic factors of survival could be useful for those managing and making treatment decisions for these patients.

Autoimmune lymphoproliferative syndrome (ALPS): a rare cause of immune cytopenia

Autoimmune Lymphoproliferative syndrome (ALPS) is an inherited disorder manifesting with autoimmune cytopenia, lymphadenopathy and splenomegaly. The differential diagnosis includes infections, autoimmune disorders or malignancies. The disease is characterized by accumulation of double negative (CD3+ CD4- CD8-) T cells (DNT) in the peripheral blood. We describe a case and review the literature.

Histopathology, parasite density and cell phenotypes of the popliteal lymph node in canine visceral leishmaniasis

While enlargement of popliteal lymph nodes (LN) is frequently described in canine visceral leishmaniasis (CVL), there are few histopathologic studies of lymph nodes during this chronic immunopathological condition. Besides a detailed histopathologic analysis, we have characterized the parasite load and major immunophenotypic features of the LN in Leishmania (Leishmania) chagasi-infected dogs. Our major histopathological findings highlight that hypertrophy/hyperplasia of LN cortical and medullary zones was the principal characteristic observed in asymptomatic dogs (AD), whereas atrophy of LN cortical zone was predominant in symptomatic animals (SD). The LN parasite density detected by anti-Leishmania immunohistochemical assay or expressed as Leishman Donovan Units was also highly correlated with the skin parasitism, the most reliable parameter to decode the clinical status of CVL. The major LN immunophenotypic changes during ongoing CVL were an increased frequency of T-lymphocytes, particularly CD8+ T-cells, up-regulation of MHC-II expression by lymphocytes and decreased levels of CD21+ B-cells. Our findings further demonstrated that changes in the LN B-lymphocyte compartment exhibited a negative correlation with the skin parasite load. Conversely, we also showed evidence for a positive association between skin parasitism and LN T-cell-mediated immunity, suggesting that T-cells, especially CD8+ lymphocytes, may have a Type-2 immunological profile in this lymphoid tissue in response to CVL.

HCV-related immunocytoma and type II mixed cryoglobulinemia-associated autoantigens

Hepatitis C virus (HCV) is a hepatotropic virus causing hepatocellular damage and chronic liver inflammation that progressively can lead to cirrhosis and hepatocellular carcinoma (HCC). HCV is also lymphotropic, as demonstrated by its capacity to replicate in lymphocytes, by the recurrent detection of organ- and non-organ-specific autoantibodies in HCV-infected patients, and by the strong association found between HCV infection and type II mixed cryoglobulinemic syndrome (MC-II). Moreover, accumulating data ascribe an etiopathogenetic role in the development of B cell non-Hodgkin's lymphomas (NHL) to HCV. All these findings account for the profound effect of HCV infection in the host's immune system. The unique virus-host interactions that culminate in the generation and sustained production of autoantibodies and cryoglobulins have not been delineated. It appears that chronic antigenic stimulation could cause the emergence of specific B cell clones that produce cryoglobulins; moreover, B cell activation and/or deregulation could originate as a result of HCV binding to CD81 tetraspanin or as a consequence of its ability to replicate in B cells. In a previous study we demonstrated that, in MC-II HCV-positive patients, cryoprecipitated monoclonal IgMs, and B cell receptors (BCR) of overexpanded B cell clones share the same combinatory region. Moreover, these IgMs were reactive against both the Fc region of human IgG and the HCV-NS3 antigen. NS3 and Fc epitopes have been idengified by epitope excision approach. One of the idengified NS3 epitopes has been used to immunize a mouse and the monoclonal antibody obtained showed the same cross-reactivity as patients' IgMs. The characterization of antigenic specificity of this antibody may be useful to idengify antigens that can stimulate B cell proliferation in HCV-infected individuals.

[Distribution of immunoglobulin like receptor gene in Han population in China and the impact thereof on the HLA-identical sibling hematopoietic stem cell transplantation]

OBJECTIVE

To investigate the distribution of killer immunoglobulin like receptor (KIR) gene in the Han population in north China and the impact of donor KIR and patient HLA genotypes on the outcome of HLA-identical sibling hematopoietic stem cell transplantation patients with hematological malignancy.

METHODS

Polymerase chain reaction with sequence-specific primers (PCR-SSP) was used to detect the KIR distribution of 150 healthy people and the KIR genotype of donor and HLA genotype of allogeneic stem cell transplantation recipients of 74 donor-recipient pairs, and a retrospective study was carried out to analyze the outcomes of 45 patients with various hematological malignancies who received non T-cell-depleted transplant from HLA-identical sibling donors, all the subjects being of Han nationality in north China.

RESULTS

The gene frequencies of KIR2DL1, KIR2DL2, KIR2DL3, and KIR3DL1 were 100%, 20%, 100%, and 95% respectively. 96% of the allogeneic donors carried one of the 3 class I ligands of inhibitory KIR. 36 of the 45 (80%) donor-recipient HLA-identical sibling transplant pairs lacked recipient HLA ligand for donor KIR, among which 35 lacked recipient HLA ligand for donor KIR2DL1, 1 pair lacked that for KIR2DL2/2DL3, and 31 pairs lacked that for KIR3DL1. Cumulative incidence analysis of graft versus host disease (GVHD) in the patients undergoing HLA-identical sibling hematopoietic stem cell transplantation demonstrated that the incidence of severe acute GVHD (aGVHD) in the patients lacking HLA ligand for donor-inhibitory KIR2DL1 was 31%, significantly lower than that of the patients with HLA ligand for donor-inhibitory KIR2DL1 (70%, P = 0.029), and the incidence of severe aGVHD in the acute myeloid leukemia patients lacking HLA ligand for donor-inhibitory KIR and KIR2DL1 was 18%, significantly lower than that of the KIR compatible patients (75%, P = 0.03).

CONCLUSION

Almost all Chinese of Han nationality in north China carry having one of the 3 known class I ligands of inhibitory KIR. KIR and KIR2DL1 mismatch is associated with lower aGVHD after HLA-identical sibling hematopoietic stem cell transplantation.

Bone marrow plasmacytosis in idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia––A report of four cases

We report on bone marrow plasmacytosis in four cases of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia (IPL). Pathologically, the plasma cells increased in number and accounted for 20-40% of nucleated cells of bone marrow. These plasma cells diffusely infiltrated or formed numerous clusters with 50-200 cells on histological sections. Some binuclear plasma cells and Russell bodies were seen, but all plasma cells showed mature cytomorphology. One case contained two lymphoid follicles with normal germinal centers. Immunoperoxidase studies of light chain determinants for plasma cells and their precursors demonstrated a polyclonal pattern. The immunohistochemical study revealed that there were no human herpes virus-8-positive cells. Bone marrow plasmacytosis of striking proportions may occur in a number of inflammatory conditions, chronic infections, autoimmune diseases, and hypersensitivity states. These reactive plasmacytoses, although sometimes striking, are generally composed of scattered, non-aggregated plasma cells. The four cases described here contained numerous tumor-like aggregations on mature plasma cells. Our four cases should be differentiated from plasma cell myeloma composed of mature plasma cells. However, electrophoresis generally demonstrated a broad-based polyclonal hypergammmaglobulinemia. Moreover, the immunohistochemical study revealed a polytypic nature of the plasma cells. To avoid overdiagnosis and overtreatment, it is important to be aware of the bone marrow findings of IPL.

Daclizumab phase II trial in relapsing and remitting multiple sclerosis: MRI and clinical results

OBJECTIVE

Daclizumab is an interleukin 2 receptor alpha chain specific humanized monoclonal antibody that has shown promising therapeutic effects in multiple sclerosis (MS). Daclizumab treatment in patients with relapsing and remitting MS was administered to determine effects on MRI and clinical outcomes.

METHODS

Patients with MS on interferon (IFN) therapy but with continuing relapses and contrast enhancing lesions (CEL) were selected. Patients were evaluated with monthly MRI scans and clinical rating scales starting 3 months prior to treatment and then at 0.5 to 27.5 months during treatment. Daclizumab (1 mg/kg IV) was administered twice in the first month (initiated and administered again in 2 weeks), followed by treatments every 4 weeks. IFN was continued until 5.5 months after daclizumab was initiated. Patients were then placed on daclizumab monotherapy. Patients with recurrent CEL were restarted on IFN with daclizumab therapy at (1.5 mg/kg IV) every 28 days.

RESULTS

Nine patients qualified for inclusion and completed the trial. Efficacy measured by both total CEL and new CEL (p < 0.001), relapses, timed ambulation, Expanded Disability Status Scale, and Neurologic Rating Scale (p < 0.05 to p < 0.01) was observed.

CONCLUSION

Daclizumab was effective in reducing contrast enhancing lesions and improving clinical scores in patients with relapsing and remitting multiple sclerosis with active disease not controlled by interferon therapy. These results provide evidence for long-term efficacy and support further clinical development of daclizumab.

Multifocal, extranodal sinus histiocytosis with massive lymphadenopathy: an overview

CONTEXT

This article provides an overview of the major pathologic manifestations of sinus histiocytosis with massive lymphadenopathy, including patient characteristics and current knowledge about its pathogenesis, with an emphasis on multifocal and extranodal presentation. Sinus histiocytosis with massive lymphadenopathy is a rare, nonneoplastic, idiopathic, proliferative histiocytic disorder; recognition of this disorder is important to avoid misinterpretation and subsequent unnecessary treatment. This is especially true for primary extranodal manifestation of this rare disorder. Although accurate diagnosis of this entity requires a correlation of clinical, radiologic, laboratory, and pathologic studies in most cases, it remains a disorder primarily defined by its histopathologic features and pathologic manifestations, which are key to the diagnosis.

OBJECTIVE

To summarize the scientific literature, provide a concise review, and emphasize the diagnostic histopathologic features of extranodal sinus histiocytosis with massive lymphadenopathy.

DATA SOURCES

A comprehensive literature review was undertaken to summarize the clinical and pathologic features of this disorder.

CONCLUSIONS

Sinus histiocytosis with massive lymphadenopathy is characterized by a rare, acquired, nonmalignant proliferation of distinctive histiocytes that present with lymphadenopathy or extranodal disease, primarily in children and young adults. It exhibits a broad range of clinical presentations, thus eliciting a wide differential diagnosis. The diverse clinical manifestations and frequent association with subtle or severe immunologic abnormalities suggest an immune-mediated cause. Additional studies are needed to characterize the interplay between death receptors and cytotoxic mediators and to further elucidate the loss of immune hemostasis that may underlie idiopathic histiocytic proliferations such as this.

Role of endogenous 4-1BB in the development of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is characterized by the production of autoantibodies directed against nuclear antigens including nucleosomes and DNA. To determine the role of T-cell costimulatory molecule 4-1BB in the regulation of SLE, MRL-Fas(lpr) (lpr) mice deficient in 4-1BB (lpr/4-1BB(-/-)) were generated and their disease phenotype was compared to that of control lpr mice. The main finding of this study is that the lpr/4-1BB(-/-) mice had more pronounced skin lesions which appeared earlier, increased lymphadenopathy, increased renal damage, and higher mortality than 4-1BB-intact control lpr mice. The increased severity of lesions in lpr/4-1BB(-/-) mice was closely associated with increases in CD4(+) T, CD3(+) B220(+) double-negative T cells, serum immunoglobulin, anti-dsDNA autoantibodies, and tissue immunoglobulin deposits. These data suggest that the 4-1BB-4-1BB ligand signalling pathway plays an important role in SLE and that deletion of 4-1BB confers susceptibility to lpr mice, leading to accelerated induction of disease and early mortality.

Abdominal aortic aneurysm is a specific antigen-driven T cell disease

To determine whether monoclonal/oligoclonal T cells are present in abdominal aortic aneurysm (AAA) lesions, we amplified beta-chain T cell receptor (TCR) transcripts from these lesions by the nonpalindromic adaptor (NPA)-polymerase chain reaction (PCR)/V-beta-specific PCR followed by cloning and sequencing. Sequence analysis revealed the presence of substantial proportions of identical beta-chain TCR transcripts in AAA lesions in 9 of 10 patients examined, strongly suggesting the presence of oligoclonal populations of alphabeta TCR+ T cells. We have also shown the presence of oligoclonal populations of gammadelta TCR+ T cells in AAA lesions. Sequence analysis after appropriate PCR amplification and cloning revealed the presence of substantial proportions of identical VgammaI and VgammaII TCR transcripts in 15 of 15 patients examined, and of Vdelta1 and Vdelta2 TCR transcripts in 12 of 12 patients. These clonal expansions were very strong. All these clonal expansions were statistically significant by the binomial distribution. In other studies, we determined that mononuclear cells infiltrating AAA lesions express early- (CD69), intermediate- (CD25, CD38), and late- (CD45RO, HLA class II) activation antigens. These findings suggest that active ongoing inflammation is present in the aortic wall of patients with AAA. These results demonstrate that oligoclonal alphabeta TCR+ and gammadelta TCR+T cells are present in AAA lesions. These oligoclonal T cells have been clonally expanded in vivo in response to yet unidentified antigens. Although the antigenic specificity of these T cells remains to be determined, these T cells may play a significant role in the initiation and/or the propagation of the AAA. It appears that AAA is a specific antigen-driven T cell disease.

Renal lesions in IgG4-related systemic disease

OBJECTIVE

Recently, a new concept of IgG4-related systemic disease including autoimmune pancreatitis, characterized by a high serum IgG4 level and tissue infiltration by IgG4-positive plasma cells, has been proposed. Our aim was to investigate the renal involvement in this condition.

PATIENTS AND METHODS

We investigated the results of laboratory and imaging studies of the kidneys in 7 patients with IgG4-related systemic disease, and examined the renal histology in four of them. All patients showed elevated serum IgG4 levels, and 4 had autoimmune pancreatitis. The other three patients showed involvement of various extrapancreatic organs (lymphadenopathy, sialadenitis or renal insufficiency), and abundant IgG4-positive plasma cell infiltration was confirmed in their affected tissues.

RESULTS

Six of the 7 patients showed some renal abnormalities. In one patient, hydronephrosis was observed accompanied by retroperitoneal fibrosis. Another patient showed multiple low-density areas in both kidneys by computed tomography, and gallium citrate scintigraphy showed gallium-67 accumulation in both kidneys, although renal function was normal. Four patients had tubulointerstitial nephritis. In two of them, the tubulointerstitial nephritis was diffuse. In one patient, marked diffuse but patchily distributed lymphoplasmacytic infiltration of the renal interstitium was observed. In another patient, computed tomography showed a tumor-like low-density mass; open biopsy of the mass showed aggregates of lymphocytes and plasma cells in the renal interstitium.

CONCLUSION

Renal parenchymal lesions in IgG4-related systemic disease are due to dense lymphoplasmacytic infiltration of the renal interstitium, and the lesions vary from diffuse tubulointerstitial nephritis to tumor-like masses according to the distribution patterns of the infiltrating cells.

NK026680, a novel suppressant of dendritic cell function, prevents the development of rapidly progressive glomerulonephritis and perinuclear antineutrophil cytoplasmic antibody in SCG/Kj mice

OBJECTIVE

NK026680 is a newly identified type of immunosuppressive agent that inhibits dendritic cell (DC) functions and consequently reduces the mortality of mice with experimental acute graft-versus-host disease. This study was undertaken to evaluate NK026680 suppression of DC functions in preventing development of rapidly progressive glomerulonephritis (RPGN) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) in SCG/Kj mice.

METHODS

Oral administration of NK026680 to SCG/Kj mice began when mice were 8-10 weeks old, before the onset of disease, and continued for 56 days. The efficacy of NK026680 was evaluated using the mortality of mice, the results of urinalysis, histopathologic evaluation for glomerular injury, and immunofluorescence staining for the detection of immune complex (IC) deposition in glomeruli, and by assessing lymphadenopathy and measuring autoantibody titers.

RESULTS

Oral administration of NK026680 at a dosage of 25 mg/kg once daily or 50 mg/kg once daily significantly suppressed 1) spontaneous mortality, 2) proteinuria and hematuria, 3) blood urea nitrogen levels, 4) glomerular damage characterized histopathologically, 5) IC deposition in glomeruli, 6) the development of pANCA and anti-DNA antibodies, and 7) lymphadenopathy.

CONCLUSION

The newly identified DC inhibitor, NK026680, prevented the onset of RPGN, autoantibody production, and lymphadenopathy in SCG/Kj mice, suggesting a crucial role for DC function in these autoimmune phenotypes. NK026680 may be a potent immunosuppressive agent for the treatment of ANCA-associated renovascular disorders.