Antibodies to hair follicles in alopecia areata

Although alopecia areata is suspected to be an autoimmune disease, no direct evidence of an altered immune response to components of the hair follicle has been reported. We studied whether antibodies to normal human anagen scalp hair follicles are present in individuals with alopecia areata. Thirty-nine alopecia areata sera and 27 control sera were tested by Western immunoblotting for antibodies to 6 M urea-extractable proteins of normal anagen scalp hair follicles. At serum diluted 1:80, all alopecia areata subjects (100%), but only 44% of control individuals, had antibodies directed to one or more antigens of approximately 57, 52, 50, 47, or 44 kD. The incidence of antibodies to individual hair follicle antigens in alopecia areata was up to seven times more frequent than in control sera and their level up to 13 times greater and was statistically significant for all five antigens. Tissue specificity analysis indicated that these antigens were selectively expressed in hair follicles. These findings indicate that individuals with alopecia areata have abnormal antibodies directed to hair follicle antigens, and support the hypothesis that alopecia areata is an autoimmune disease.     

Comparison of alopecia areata in human and nonhuman mammalian species

Alopecia areata (AA) is a nonscarring form of inflammatory hair loss in humans. AA-like hair loss has also been observed in other species. In recent years the Dundee experimental bald rat and the C3H/HeJ mouse have been put forward as models for human AA. AA in all species presents with a wide range of clinical features from focal, locally extensive, diffuse hair loss, to near universal alopecia. Histologically, all species have dystrophic anagen stage hair follicles associated with a peri- and intrafollicular inflammatory cell infiltrate. Autoantibodies directed against anagen stage hair follicle structures are a consistent finding. Observations on AA pathogenesis suggest nonhuman species can provide excellent models for the human disease. Ultimately, animal models will be used to determine the genetic basis of AA, potential endogenous and/or environmental trigger(s), mechanism(s) of disease initiation and progression, and allow rapid evaluation of new and improved disease treatments.     

Different populations of melanocytes are present in hair follicles and epidermis

Melanocytes in human skin reside both in the epidermis and in the matrix and outer root sheath of anagen hair follicles. Comparative study of melanocytes in these different locations has been difficult as hair follicle melanocytes could not be cultured . In this study we used a recently described method of growing hair follicle melanocytes to characterize and compare hair follicle and epidermal melanocytes in the scalp of the same individual. Three morphologically and antigenically distinct types of melanocytes were observed in primary culture. These included (1) moderately pigmented and polydendritic melanocytes derived from epidermis; (2) small, bipolar, amelanotic melanocytes; and (3) large, intensely pigmented melanocytes; the latter two were derived from hair follicles. The three sub-populations of cells all reacted with melanocyte-specific monoclonal antibody. Epidermal and amelanotic hair follicle melanocytes proliferated well in culture, whereas the intensely pigmented hair follicle melanocytes did not. Amelanotic hair follicle melanocytes differed from epidermal melanocytes in being less differentiated, and they expressed less mature melanosome antigens. In addition, hair follicle melanocytes expressed some antigens associated with alopecia areata, but not antigens associated with vitiligo, whereas the reverse was true for epidermal melanocytes. Thus antigenically different populations of melanocytes are present in epidermis and hair follicle. This could account for the preferential destruction of hair follicle melanocytes in alopecia areata and of epidermal melanocytes in vitiligo.     

Acquired scalp alopecia. Part I: A review

In this two-part series we review the acquired scalp alopecias. A broad spectrum of diseases result in alopecia. In this first part we provide a framework for the assessment and diagnosis of scalp hair loss, and begin covering the individual conditions. The non-scarring alopecias covered include effluvium, androgenetic alopecia, alopecia areata, trichotillomania, and loose anagen syndrome. The scarring alopecias cause permanent pilosebaceous follicle loss; the lymphocyte-associated scarring alopecia described encompasses lichen planopilaris, discoid lupus erythematosus, pseudopelade, and follicular mucinosis. Part II will cover the neutrophil-associated and infiltrative processes causing scarring alopecia followed by the medical management of alopecia. There is particular reference to newly described conditions and progress in the understanding of older conditions. More recently characterized conditions include the loose anagen syndrome, chronic telogen effluvium, and the frontal fibrosing variant of lichen planopilaris.     

Loose anagen syndrome and loose anagen hair

Loose anagen syndrome, or loose anagen hair, is a recently described condition of unknown etiology that may be under-recognized. The typical patient is a child with sparse fine hair that can easily be pulled out. The diagnosis is confirmed by microscopic examination of firmly pulled hairs, many of which are in the anagen phase but lacking an inner and outer root sheath and demonstrating a ruffled cuticle. Some presentations of alopecia areata may be confused with this condition, but the pull test analysis serves to differentiate them. A variety of theories have been postulated to explain the pathophysiology of loose anagen syndrome. In some cases, there is an autosomal dominant pattern of inheritance. In most cases, this condition spontaneously improves with age.     

Alopecia areata and increased prevalence of psychiatric disorders

BACKGROUND: The relationship between psychiatric disorders and alopecia areata has not been well studied. Although previous reports have been unable to correlate psychiatric illness with hair loss, a recent study determined that 74% of patients with alopecia areata (AA) under evaluation had one or more lifetime psychiatric diagnoses. METHODS: Two hundred and ninety-four community-based patients with alopecia areata responded to a detailed questionnaire distributed by Help Alopecia International Research, Inc. The prevalence of psychiatric disorders was determined using diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IIIR). RESULTS: Major depression, generalized anxiety disorder, social phobia, and paranoid disorder were all present in patients with alopecia areata at rates significantly higher than in the general population. CONCLUSIONS: Alopecia areata patients are at a higher risk of developing psychiatric comorbidity during their clinical course.     

A controlled study of the effects of RU58841, a non-steroidal antiandrogen, on human hair production by balding scalp grafts maintained on testosterone-conditioned nude mice

Human hair growth can be monitored for several months after the transplantation of scalp samples from men with androgen-dependent alopecia on to female nude mice. Hair production from balding sites has been shown to be inhibited in testosterone-conditioned nude mice. We used this recently reported model to study the effect of a new non-steroidal antiandrogen-RU58841-on human hair growth. Twenty productive scalp grafts from balding men were maintained for 8 months after grafting on to nude mice, and hair production was monitored monthly for 6 months. All mice were conditioned by the topical application of testosterone (testosterone propionate, 300 micrograms in 10 microL; 5 days/week) on the non-grafted flank. The scalp samples were divided equally according to the estimated hair production potential, which was based on the amount of hair present on the scalp samples before grafting. Each of the two equal groups of grafts was further allocated at random to be treated topically (5 days/week) with blinded solutions of either RU58841 1% in ethanol, or ethanol as a control. Twenty-eight active follicles appeared on the 10 control grafts. Among them only two follicles (7%) initiated a second hair cycle. However, the 10 RU58841-treated grafts bore a total of 29 active follicles, and eight of them (28%) showed a second cycle. The values for the linear hair growth rates (LHGR) were significantly (P < 0.04) higher in the RU58841-treated group. Recycling and increased LHGR indicate a positive action for RU58841 on human hair growth from balding samples grafted on to testosterone-conditioned nude mice, and encourage a clinical trial to evaluate its potential in the treatment of androgen-dependent alopecia.     

Why is the cesarean delivery rate so high in Alabama? An examination of risk factors, 1991-1993

A new autosomal recessive mutation of the house mouse developed generalized alopecia associated with breakage of abnormal hair shafts. This mutation, named 'lanceolate hair' (symbol: lah), arose in a mutagenesis experiment using ethylnitrosourea. Hair shafts were short with a focal degeneration at the breakpoint characterized by a pronounced enlargement at the apex, resembling a lance head. Plucked hair fibers were 2.0 to 3.5 mm in length with a normal base, suggesting that there was a synchronized developmental defect. Histologic examination of anagen follicles revealed abnormal cornification of the matrix region with degeneration resulting in the focal hair shaft deformity. Catagen follicles showed pronounced follicular dystrophy but telogen follicles were almost normal. There was a marked, persistent thickening of the epidermis associated with a non-scarring, relatively non-inflammatory ichthyosiform dermatitis. These features are found in the Netherton's syndrome of the human, for which this mouse mutation may represent a model. The lah mutation has been localized to the centromeric end of mouse Chromosome 18.     

Alterations in gastric physiology in Helicobacter pylori infection: causes of different diseases or all epiphenomena?

Although mice of the C3H strain normally respond to bacterial lipopolysaccharide with appropriate immune system activation, mice of the C3H/HeJ substrain do not because of a gene defect. This suggests they may be more susceptible to opportunistic bacterial infections and more likely to have otitis media than a normally responding substrain, such as the C3H/HeSnJ. Therefore these two substrains were evaluated for incidence of spontaneous middle ear disease at 2, 4, 6, 10, 12, 15, and 18 months of age. Auditory brain stem response audiometry to pure tones of 4, 8, 16, 24, and 32 kHz was performed to establish the impact of middle ear disease on auditory function. None of the lipopolysaccharide-responsive C3H/HeSnJ mice demonstrated middle ear disease. However, middle ear disease was present in 33% of the C3H/HeJ mice. The conductive loss caused by the otitis media resulted in auditory brain stem response threshold shifts of 15 to 40 dB SPL, lowered peak amplitudes, and increased latencies. Reduced lipopolysaccharide responsiveness by C3H/HeJ mice makes them less capable of reacting immunologically to bacterial infection and presumably underlies the failure to clear middle ear disease. The C3H/HeJ mouse may provide a valuable model in which to study lipopolysaccharide biologic activity and related middle ear inflammatory or immune mechanisms.     

Intact hair follicle innervation is not essential for anagen induction and development

Neuropeptides produced, stored and secreted by the unusually dense sensory and autonomic innervation of hair follicles (HFs) can induce hair growth (anagen) and may be involved in hair growth control. To test the role of follicle innervation of HF cycling in vivo, we generated innervation-deficient HFs by unilateral surgical denervation of a defined region of back skin in C57BL/6 mice and assessed its effect on spontaneous and induced anagen development. Successful denervation was demonstrated by the absence of PGP 9.5+ or tyrosine hydroxylase+ nerves and nerve-associated neuropeptides (substance P, CGRP). By quantitative histomorphometry, no significant difference in spontaneous or cyclosporin A-induced anagen development could be detected between sham-operated control skin and denervated skin. Only after hair growth induction by depilation, a discrete, marginally significant retardation of anagen development was apparent in denervated HFs. Thus, even though cutaneous nerves may exert a minor modulatory role in depilation-induced hair growth, they are not essential for normal murine anagen development.     

Hair diseases

A few common causes of hair loss account for the vast majority of cases. A well-directed history and simple physical examination is often sufficient to make a diagnosis. Laboratory testing is often unnecessary. A scalp biopsy can be useful, but only if processed and interpreted correctly. Androgenetic alopecia, alopecia areata, senescent alopecia, telogen effluvium, traction alopecia, trichotillomania, and cosmetic hair damage are common causes of non-scarring alopecia. Discoid lupus erythematosus, lichen planopilaris, and central, centrifugal scarring alopecia are the most common forms of scarring hair loss.     

Treatment of alopecia areata

Some individuals question whether any treatment is effective in severe alopecia areata. Certainly many patients, especially those with mild disease, experience spontaneous hair regrowth; however, results of double-blind studies clearly indicate that some treatments do promote hair regrowth even in those with extensive disease. Some patients never show either spontaneous or treatment-related hair regrowth; others experience hair regrowth only while maintained on treatment, repeatedly losing hair within a few weeks of discontinuing treatment and regrowing it within several weeks after restarting treatment. Some patients who have been responsive to treatment may experience exacerbation of their disease such that even high-dose systemic steroids do not prevent the development of alopecia universalis. Some treatments appear to work on some patients some or all of the time, but no treatment appears to work on all patients all of the time. We would suggest a few practical points that we find useful: To maximize the potential for cosmetic hair growth in alopecia areata that is extensive or flaring, treat the entire scalp instead of "chasing" patches. Do not change any topical treatment sooner than 3 months after starting it; early regrowth may first be present at 3 months. Cosmetic regrowth may take a year or more to achieve. Maintenance treatment increases the likelihood of maintenance of cosmetic hair growth, but patches of hair loss may still come and go. Atopic patients who experience seasonal hair loss may benefit (ie, have less severe hair loss flares or respond more readily to topical therapy) by using an antihistamine or mast cell stabilizer prophylactically. Whether one looks at the therapeutic cup as half full or half empty, most patients urge us to continue to try to find safe, effective long-term treatments for this disease.     

Harlequin ichthyosis (ichq): a juvenile lethal mouse mutation with ichthyosiform dermatitis

The harlequin ichthyosis (ichq) mouse mutation arose spontaneously in 1989 in a colony of BALB/cJ mice at The Jackson Laboratory. Affected mice developed thick skin due to formation of compact, orthokeratotic scales that fractured over articular surfaces, secondary to bending. Harlequin ichthyosis mice on the inbred BALB/cJ background died between 9 and 12 days of age. Onset of the clinical phenotype corresponded with emergence of hair fibers from follicles at 5 days of age. There was marked proliferation of the root sheaths of anagen hair follicles, limited to the region within the dermis. Sebaceous glands were present but small compared with those of littermate controls. Emerging hair fibers were surrounded by a thick, compact sheath of cornified cells. Mutant skin contained large mitochondria with lamellar-shaped, electron-dense structures at the ultrastructural level. Keratohyalin granules were smaller and less pleomorphic than those in control mice. Lamellar bodies were not evident in either mutant or littermate control mice. Using a panel of antibodies to evaluate changes in keratinocyte differentiation, mouse-specific keratin 6 was overexpressed in the suprabasilar, hyperplastic epidermis. Loricrin expression, within the cytoplasm of cells in the stratum granulosum, decreased rapidly postmortem, unlike that in normal mice where it was stable for over 24 hours postmortem. Filaggrin expression, within granules of cells in the stratum granulosum, was prominent, corresponding to hypergranulosis evident by light microscopy in mutant mouse skin. Skin grafts from harlequin ichthyosis mice grafted onto immunodeficient nude mice maintained the phenotype for the 10-week observation period. The mutant gene locus mapped to the proximal end of mouse chromosome 19 and is inherited as a fully penetrant autosomal recessive gene. The harlequin ichthyosis mouse mutation is very similar to human type 2 harlequin ichthyosis for which it may be a good model.     

Ketoconazole shampoo: effect of long-term use in androgenic alopecia

BACKGROUND: The pathogenesis of androgenic alopecia is not fully understood. A microbial-driven inflammatory reaction abutting on the hair follicles might participate in the hair status anomaly. OBJECTIVE: The aim of our study was to determine if ketoconazole (KCZ) which is active against the scalp microflora and shows some intrinsic anti-inflammatory activity might improve alopecia. METHOD: The effect of 2% KCZ shampoo was compared to that of an unmedicated shampoo used in combination with or without 2% minoxidil therapy. RESULTS: Hair density and size and proportion of anagen follicles were improved almost similarly by both KCZ and minoxidil regimens. The sebum casual level appeared to be decreased by KCZ. CONCLUSION: Comparative data suggest that there may be a significant action of KCZ upon the course of androgenic alopecia and that Malassezia spp. may play a role in the inflammatory reaction. The clinical significance of the results awaits further controlled study in a larger group of subjects.     

Role of macrophages in regeneration of liver

In an attempt to clarify the role of macrophages and their mediators during regeneration of the liver, the difference of liver regeneration among C3H/HeN (LPS-responsive strain) and C3H/HeJ (LPS-resistant strain) mice was investigated. After a 67% partial hepatectomy, an increase in the weight of regenerating liver was significantly delayed in the C3H/HeJ mice, as compared with C3H/HeN mice. The number of hepatocytes labeled with antibody against PCNA reached maximum levels 48 hr after partial hepatectomy, but the PCNA labeling index in C3H/HeJ mice was 20% less than that for C3H/HeN mice. In addition, TNF-alpha activities in serum were enhanced shortly after partial hepatectomy in C3H/HeN strain mice, but were not increased in C3H/HeJ strain mice. Serum IL-6 levels were markedly enhanced in both C3H/HeN and C3H/HeJ mice, but a bimodial peak (14 and 48 hr after partial hepatectomy) was demonstrated in C3H/HeN mice, in contrast to a single peak (at 24 hr) in C3H/HeJ mice. Suppression of Kupffer cells by previous administration of gadolinium chloride in C3H/HeN mice reduced the increase in both serum TNF-alpha and IL-6 concentrations, reduced PCNA labeling index of hepatocytes by 20%, and disturbed the regeneration of the liver. Previous administration of antibody against TNF-alpha reduced the PCNA labeling index of hepatocytes by 20% after partial hepatectomy in C3H/HeN strain mice. These results suggest that LPS-responsive macrophages in the liver and their mediators, especially TNF-alpha, could partly play a role in liver regeneration.     

Significant contribution of spleen cells in mediating the lethal effects of endotoxin in vivo

Two closely related, histocompatible mouse strains that have marked differences in both in vitro and in vivo responses to endotoxin were used to evaluate the contribution of lymphoid cells to the lethal effect of endotoxin. C3H/HeJ mice are endotoxin resistant, whereas C3H/HeN mice are endotoxin sensitive. In vitro spleen cell mitogenic responses to endotoxin were similar in untreated mice and in mice that received sublethal irradiation (450 R) followed by reconstitution with autologous spleen cells. Reconstitution with spleen cells from the related strain produced chimeric animals with spleen cell mitogenic activity like that of the donor strain. When chimeric animals were subjected to a lethal challenge of endotoxin, their response was markedly altered by the transferred lymphoid cells. C3H/HeJ animals reconstituted with C3H/HeN cells became more endotoxin sensitive, whereas C3H/HeJ cells became more endotoxin resistant. These results indicate that spleen cells play a significant, detrimental role in endotoxin-induced lethality.     

Hair cycle-dependent plasticity of skin and hair follicle innervation in normal murine skin

The innervation of normal, mature mammalian skin is widely thought to be constant. However, the extensive skin remodeling accompanying the transformation of hair follicles from resting stage through growth and regression back to resting (telogen-anagen-catagen-telogen) may also be associated with alteration of skin innervation. We, therefore, have investigated the innervation of the back skin of adolescent C57BL/6 mice at various stages of the depilation-induced hair cycle. By using antisera against neuronal (protein gene product 9.5 [PGP 9.5], neurofilament 150) and Schwann cell (S-100, myelin basic protein) markers, as well as against neural cell adhesion molecule (NCAM) and growth-associated protein-43 (GAP-43), we found a dramatic increase of single fibers within the dermis and subcutis during early anagen. This was paralleled by an increase in the number of anastomoses between the cutaneous nerve plexuses and by distinct changes in the nerve fiber supply of anagen vs. telogen hair follicles. The follicular isthmus, including the bulge, the seat of epithelial follicle stem cells, was found to be the most densely innervated skin area. Here, a defined subpopulation of nerve fibers increased in number during anagen and declined during catagen, accompanied by dynamic alterations in the expression of NCAM and GAP-43. Thus, our study provides evidence for a surprising degree of plasticity of murine skin innervation. Because hair cycle-associated tissue remodeling evidently is associated with tightly regulated sprouting and regression of nerve fibers, hair cycle-dependent alterations in murine skin and hair follicle innervation offer an intriguing model for studying the controlled rearrangement of neuronal networks in peripheral tissues under physiological conditions.