Presence of Senescent and Memory CD8+ Leukocytes as Immunocenescence Markers in Skin Lesions of Elderly Leprosy Patients.

Leprosy is an infectious disease that remains endemic in approximately 100 developing countries, where about 200,000 new cases are diagnosed each year. Moreover, multibacillary leprosy, the most contagious form of the disease, has been detected at continuously higher rates among Brazilian elderly people. Due to the so-called immunosenescence, characterized by several alterations in the quality of the immune response during aging, this group is more susceptible to infectious diseases. In view of such data, the purpose of our work was to investigate if age-related alterations in the immune response could influence the pathogenesis of leprosy. As such, we studied 87 individuals, 62 newly diagnosed and untreated leprosy patients distributed according to the age range and to the clinical forms of the disease and 25 healthy volunteers, who were studied as controls. The frequency of senescent and memory CD8+ leukocytes was assessed by immunofluorescence of biopsies from cutaneous lesions, while the serum levels of IgG anti-CMV antibodies were analyzed by chemiluminescence and the gene expression of T cell receptors' inhibitors by RT-qPCR. We noted an accumulation of memory CD8+ T lymphocytes, as well as reduced CD8+CD28+ cell expression in skin lesions from elderly patients, when compared to younger people. Alterations in LAG3 and PDCD1 gene expression in cutaneous lesions of young MB patients were also observed, when compared to elderly patients. Such data suggest that the age-related alterations of T lymphocyte subsets can facilitate the onset of leprosy in elderly patients, not to mention other chronic inflammatory diseases.

Neutrophils in Leprosy.

Leprosy is an infectious disease caused by the intracellular bacillus Mycobacterium leprae that mainly affects the skin and peripheral nerves. One of the most intriguing aspects of leprosy is the diversity of its clinical forms. Paucibacillary patients are characterized as having less than five skin lesions and rare bacilli while the lesions in multibacillary patients are disseminated with voluminous bacilli. The chronic course of leprosy is often interrupted by acute episodes of an inflammatory immunological response classified as either reversal reaction or erythema nodosum leprosum (ENL). Although ENL is considered a neutrophilic immune-complex mediated condition, little is known about the direct role of neutrophils in ENL and leprosy disease overall. Recent studies have shown a renewed interest in neutrophilic biology. One of the most interesting recent discoveries was that the neutrophilic population is not homogeneous. Neutrophilic polarization leads to divergent phenotypes (e.g., a pro- and antitumor profile) that are dynamic subpopulations with distinct phenotypical and functional abilities. Moreover, there is emerging evidence indicating that neutrophils expressing CD64 favor systemic inflammation during ENL. In the present review, neutrophilic involvement in leprosy is discussed with a particular focus on ENL and the potential of neutrophils as clinical biomarkers and therapeutic targets.

Immunohistochemical characterization of the M4 macrophage population in leprosy skin lesions.

BACKGROUND: Since macrophages are one of the major cell types involved in the Mycobacterium leprae immune response, roles of the M1 and M2 macrophage subpopulations have been well defined. However, the role of M4 macrophages in leprosy or other infectious diseases caused by mycobacteria has not yet been clearly characterized. This study aimed to investigate the presence and potential role of M4 macrophages in the immunopathology of leprosy. METHODS: We analyzed the presence of M4 macrophage markers (CD68, MRP8, MMP7, IL-6, and TNF-α) in 33 leprosy skin lesion samples from 18 patients with tuberculoid leprosy and 15 with lepromatous leprosy by immunohistochemistry. RESULTS: The M4 phenotype was more strongly expressed in patients with the lepromatous form of the disease, indicating that this subpopulation is less effective in the elimination of the bacillus and consequently is associated with the evolution to one of the multibacillary clinical forms of infection. CONCLUSION: M4 macrophages are one of the cell types involved in the microbial response to M. leprae and probably are less effective in controlling bacillus replication, contributing to the evolution to the lepromatous form of the disease.

Cutaneous plasmacytosis: A rare entity with unique presentation.

Primary cutaneous plasmacytosis is a rare cutaneous disorder with extensive cutaneous plaques/papules mainly on the trunk and face. Cases have mostly been documented from Japan. We present here a rare case of cutaneous plasmacytosis from India of Mongolian descent. This 50-year-old female from Mizoram had extensive maculo-papular violaceous plaques distributed on the face, axillae, trunk and lower extremities. Initial and repeat skin biopsy revealed dense perivascular and periadnexal mature plasma cells. She also had lymphadenopathy. Serum protein electrophoresis did not reveal any M band and the Bence Jones protein was negative in urine. The patient had multiple superficial lymph nodes and a biopsy from the cervical lymph node showed effacement of normal nodal architecture by sheets of plasma cells. Immuno histochemistry was done from both skin and lymph node biopsies. The kappa and lambda tight chains were not restricted; there by proving the polyclonal nature of the plasma cells. The novelty of the case lies in its classical clinical presentation with histopathological documentation.

In Situ complement activation and T-cell immunity in leprosy spectrum: An immunohistological study on leprosy lesional skin.

Mycobacterium leprae (M. leprae) infection causes nerve damage and the condition worsens often during and long after treatment. Clearance of bacterial antigens including lipoarabinomannan (LAM) during and after treatment in leprosy patients is slow. We previously demonstrated that M. leprae LAM damages peripheral nerves by in situ generation of the membrane attack complex (MAC). Investigating the role of complement activation in skin lesions of leprosy patients might provide insight into the dynamics of in situ immune reactivity and the destructive pathology of M. leprae. In this study, we analyzed in skin lesions of leprosy patients, whether M. leprae antigen LAM deposition correlates with the deposition of complement activation products MAC and C3d on nerves and cells in the surrounding tissue. Skin biopsies of paucibacillary (n = 7), multibacillary leprosy patients (n = 7), and patients with erythema nodosum leprosum (ENL) (n = 6) or reversal reaction (RR) (n = 4) and controls (n = 5) were analyzed. The percentage of C3d, MAC and LAM deposition was significantly higher in the skin biopsies of multibacillary compared to paucibacillary patients (p = <0.05, p = <0.001 and p = <0.001 respectively), with a significant association between LAM and C3d or MAC in the skin biopsies of leprosy patients (r = 0.9578, p< 0.0001 and r = 0.8585, p<0.0001 respectively). In skin lesions of multibacillary patients, MAC deposition was found on axons and co-localizing with LAM. In skin lesions of paucibacillary patients, we found C3d positive T-cells in and surrounding granulomas, but hardly any MAC deposition. In addition, MAC immunoreactivity was increased in both ENL and RR skin lesions compared to non-reactional leprosy patients (p = <0.01 and p = <0.01 respectively). The present findings demonstrate that complement is deposited in skin lesions of leprosy patients, suggesting that inflammation driven by complement activation might contribute to nerve damage in the lesions of these patients. This should be regarded as an important factor in M. leprae nerve damage pathology.

Therapeutic potential of biosimilars in dermatology.

The introduction of biologic therapy has revolutionized the treatment of many chronic diseases, including several dermatological disorders. Biological agents promise to satisfy medical needs previously unmet by conventional medicines. Unfortunately, these agents are expensive and out of reach for the majority of patients who need them. Biosimilars are copies of the innovator biological agents and represent an important advance in the field of biological therapeutics. Although they are similar to the original biologic, differences in terms of structure, efficacy, safety and immunogenicity remain a concern. Thus, biosimilars cannot be regarded as bio-generics. Awareness of the key differences between a biosimilar and its reference biological agent is essential for optimal treatment and safety of patients. The increasing availability of biosimilars provides patients and doctors with less expensive alternatives and increases the accessibility of biologic therapy to needy patients. In this review, we discuss the concept of biosimilars, the need for appropriate regulatory pathways and their current status in dermatology.

Disseminated infection with Lacazia loboi and immunopathology of the lesional spectrum.

The pathogenesis of lacaziosis continues to be obscure, and works have investigated the blood systemic immune response or the dermal immune response in restricted lesions in different body regions. Some authors describe that the inflammatory infiltrate in lacaziosis lesions showed a predominance of macrophages followed by CD45RO(+), CD4(+), and CD8(+) T cells; CD57(+) natural killer cells; S-100(+) cells; and CD20(+) B lymphocytes. A 54-year-old man and living in the State of Para, Amazon region, Brazil, was seen with a lesion on the left lower limb, which had started as a small nodular area 18 years ago. The lesion showed progressive growth and disseminated to other parts of the body. Our findings showed that dermal immune response differs depending on the type of lesions and clinical presentation, with presence of CD1a(+), FXIIIa(+), CD45(+), CD4(+), CD8(+), and S-100(+) cells and cytokine profile with expression of interleukin 1 ß, tumor necrosis factor α, transforming growth factor ß, IL-10, and interferon γ.

Safety and effectiveness of autoinoculation therapy in cutaneous warts: a double--blind, randomized, placebo--controlled study.

BACKGROUND: In spite of the availability of multiple treatment options, viral warts are known for their persistence and recurrence, causing frustration to patients and treating physicians. AIMS: To study the effectiveness and safety of autoinoculation as a treatment modality in cutaneous warts. METHODS: A double-blind, placebo-controlled study was carried out. In the treatment group, full-thickness warty tissue was excised, minced and implanted in a small dermal pocket. In the control group, warty tissue was only excised and not implanted, though a dermal pocket was made. Patients were evaluated every four weeks with lesion counts. The procedure was repeated at 4 and 8 weeks. Response was assessed at each visit and at 12 weeks. RESULTS: Forty-eight patients with cutaneous warts (male: female=32:16) were randomized into autoinoculation and control groups. The number of warts at baseline was comparable in both groups (P=0.293). Reduction in the number of warts was significantly more in the autoinoculation group (8.50±13.88) than in the control group (10.04±5.80) from 8 weeks onwards (P=0.010). Complete resolution occurred only in the autoinoculation group, in 62.5% of cases. Adverse effects were seen in 11 patients, including infection of the donor site (5 cases), keloid formation (3) and hypopigmentation (3). CONCLUSION: Autoinoculation may be an effective therapeutic modality for cutaneous warts and two sessions may be required for optimum results.

Histopathological study of cutaneous manifestations in HIV and AIDS patients.

OBJECTIVES: Most human immunodeficiency virus (HIV)-infected patients develop various skin diseases. These skin manifestations not only act as markers but also reflect the patient's underlying immune status. Investigating CD4 counts is costly and not always possible. Thus, the potential value to be gained by using skin manifestations as predictors of low CD4 counts and disease progression should be explored. The present study attempted to correlate the association of various cutaneous disorders found in HIV patients with CD4 and CD8 counts, the CD4 : CD8 ratio and stage of HIV infection. METHODS: This was a prospective study involving 61 patients who were HIV-positive and demonstrated skin lesions. Punch biopsies of skin were taken for histopathological diagnosis. CD4 and CD8 T cell counts were performed. RESULTS: The study sample included a majority of male patients, most of whom were aged 21-40 years. Pruritic papular dermatitis was the most common skin manifestation, followed by molluscum contagiosum, eosinophilic folliculitis, and Hansen's disease. Most of the lesions were associated with CD4 counts of <220/µl (n = 38). All skin lesions associated with HIV or acquired immune deficiency syndrome (AIDS) showed a CD4 : CD8 ratio of <0.50. CONCLUSIONS: The study findings demonstrate an inverse relationship between CD4 counts and the occurrence of skin lesions. The majority of lesions were associated with stage 3 or stage 4 infection. Thus, specific cutaneous manifestations can be considered as good clinical indicators for predicting underlying immune status in resource-poor countries.

[What's new in clinical dermatology?]. / Quoi de neuf en dermatologie clinique?

This year more than 3000 medical articles referenced in PubMed concerned dermatology. Our critical analysis covers different fields of dermatology: including epidemiology, clinical, diagnostic and prognostic factors. AIDS is 30 years old and the national HIV/AIDS plan for 2010-2014 recommends generalized screening facilitated by the introduction of rapid tests for diagnostic orientation. In infectious diseases, novelties concern polyomavirus, HTLV-1, leprosy, staphylococcus infections, resistance to antibiotics and scabies. Diseases of the scalp consecutive to practices of black women hairstyles were the subject of important articles. There were two important developments in acne: first, a simplified and more operational classification, secondly a suicidal risk associated with severe forms. Lymphocyte Th-17 immunity is involved in clinical phenomena either by excess (genetic or drug) or default (genetic causes). Allergology: in several studies, false negative patch tests have been published. The natural history of nevi is specified by three important articles. Serological tests to practice in cases of dermatomyositis and bullous pemphigoid are specified.

Skin in aviation and space environment.

The aerospace environment is a dynamic interaction between man, machine and the environment. Skin diseases are not particularly significant aeromedically, yet they could permanently affect an aviator's status for continued flying duty. A number of dermatological conditions lend themselves to flying restrictions for the aviator. Aircrew and ground crew are exposed to a myriad of elements that could also adversely impact their flying status. Inflight stresses during flights as well as space travel could impact certain behaviors from a dermatological standpoint. With the advent of space tourism, dermatological issues would form an integral part of medical clearances. With limited literature available on this subject, the review article aims to sensitize the readers to the diverse interactions of dermatology with the aerospace environment.

Toll-like receptors and skin.

Toll-like receptors are important pattern recognition receptors which have key roles in both innate and adaptive immune responses. They are strongly associated with the pathogenesis of inflammatory and autoimmune diseases. Furthermore, Toll-like receptors have also been implicated in the pathogenesis of several skin diseases such as skin infections, psoriasis, acne vulgaris, lichen planus, Behçet's disease, leprosy, syphilis, Lyme disease, atopic dermatitis and allergic contact dermatitis, mycosis fungoides, non-melanoma skin cancers and melanoma. In this manuscript, the structure and functions of Toll-like receptors in immune responses, their impact on skin diseases and recent advances on therapeutic usage have been reviewed.

Immune reconstitution inflammatory syndrome and tropical dermatoses.

The human immunodeficiency virus (HIV) pandemic has disproportionately affected tropical regions of the world, where dermatoses, such as leprosy and leishmaniasis, rarely encountered in temperate climates, are endemic. Although the introduction of highly active antiretroviral therapy (HAART) has been lifesaving, a few patients undergoing HAART experience clinical deterioration caused by immune reconstitution inflammatory syndrome (IRIS). This article explores the range of tropical dermatoses that are reported to date with associated IRIS events.

Direct immunofluorescence of skin biopsy: perspective of an immunopathologist.

BACKGROUND: By direct immunofluorescence (DIF), presence of immune complexes in the skin biopsy at various locations such as the dermo-epidermal junction, dermal blood vessels, etc. help to arrive at a diagnosis. AIMS: (1) To study the role of DIF in confirmation or exclusion of diseases involving skin vis-à-vis histopathology and clinical diagnosis, (2) to describe the annual spectrum of dermatologic conditions that present to a tertiary referral center and require DIF examination of skin biopsy for confirmation of diagnosis. METHODS: A total of 267 biopsies received over a period of 16 months in the Department of Immunopathology were analyzed along with clinical and histopathological details and the correlation between them was studied. RESULTS: DIF was positive in 204 skin biopsies. Of these, 127 biopsies showed good clinico-immuno-histopathological correlation. In 10 cases, only DIF could clinch the diagnosis. In another nine cases, immune deposits were noted, which were unexpected in light of clinical and histopathological diagnosis. The most common skin involvement was seen in vasculitides. DIF was, however, non-contributory in lesions like erythema multiformè, post Kala-azar dermal leishmaniasis, sarcoidosis, lupus vulgaris, pyoderma gangrenosum and prurigo nodularis. CONCLUSION: The DIF of skin in conjunction with histopathology gives the best diagnostic yield. It is invaluable in confirming the diagnosis of small vessel vasculitides and bullous lesions of skin and can be used as an additional tool to pinpoint the diagnosis of systemic and localized autoimmune diseases involving the skin.

The role of toll-like receptors in host defenses and their relevance to dermatologic diseases.

The family of toll-like receptors (TLRs) plays a central role in the cutaneous immune defense system. To date, different TLRs have been found on several major cell populations of the skin, such as keratinocytes, fibroblasts, antigen-presenting cells, and melanocytes. Activation of TLRs leads, via different intracellular signaling pathways, to the production of pro-inflammatory stimuli, and is considered a danger signal that should transform the skin in to the functional state of defense. However, TLRs have also been implicated in tissue homeostasis and renewal. Within the group of TLRs, two types have been identified: surface-expressed TLRs, which are predominantly active against bacterial cell wall compounds; and intracellular receptors, which preferentially recognize virus-associated pattern molecules. In addition, surface-expressed receptors trigger phagocytotic and maturation signals, while the intracellular TLRs lead to the induction of antiviral genes. Our review aims to outline the importance of TLRs in the pathogenesis of numerous skin diseases and the potential of TLR agonists as a treatment option for various skin diseases.