Alopecia areata: immunofluorescence and other studies

A "hair-raising" history of alopecia areata

A 3500-year-old papyrus from ancient Egypt provides a list of treatments for many diseases including "bite hair loss," most likely alopecia areata (AA). The treatment of AA remained largely unchanged for over 1500 years. In 30 CE, Celsus described AA presenting as scalp alopecia in spots or the "windings of a snake" and suggested treatment with caustic compounds and scarification. The first "modern" description of AA came in 1813, though treatment still largely employed caustic agents. From the mid-19th century onwards, various hypotheses of AA development were put forward including infectious microbes (1843), nerve defects (1858), physical trauma and psychological stress (1881), focal inflammation (1891), diseased teeth (1902), toxins (1912) and endocrine disorders (1913). The 1950s brought new treatment developments with the first use of corticosteroid compounds (1952), and the first suggestion that AA was an autoimmune disease (1958). Research progressively shifted towards identifying hair follicle-specific autoantibodies (1995). The potential role of lymphocytes in AA was made implicit with immunohistological studies (1980s). However, studies confirming their functional role were not published until the development of rodent models (1990s). Genetic studies, particularly genome-wide association studies, have now come to the forefront and open up a new era of AA investigation (2000s). Today, AA research is actively focused on genetics, the microbiome, dietary modulators, the role of atopy, immune cell types in AA pathogenesis, primary antigenic targets, mechanisms by which immune cells influence hair growth, and of course the development of new treatments based on these discoveries.

Familial aggregation of alopecia areata

BACKGROUND

Familial aggregation of alopecia areata (AA) has been previously described, but systematic studies with information obtained directly from family members have yet to be undertaken.

OBJECTIVE

We sought to study the pattern of familial aggregation of AA by assessing the affection status of patients' relatives. The study included 206 index patients with a total of 1029 first-degree and 2625 second-degree relatives.

METHODS

First-degree relatives were directly interviewed, whereas information on second-degree relatives was obtained by interviewing the index patients and their first-degree relatives.

RESULTS

Estimated lifetime risks were 7.1% in siblings, 7.8% in parents, and 5.7% in offspring. The risk in second-degree relatives was slightly higher than the reported population risk. Age at onset in index patients and first-degree relatives was significantly correlated.

LIMITATIONS

Using patients drawn from specialized hair clinics may have produced results showing a higher proportion of early onset and severe cases.

CONCLUSION

The familial aggregation of AA supports the role of genetic factors in the development of the disease. In addition, our data indicate genetic factors might contribute to the age at onset of AA.

The genetic epidemiology of alopecia areata in China

BACKGROUND

Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease with genetic predisposition and an environmental trigger. There are few clinical data in Asians.

OBJECTIVES

To describe the genetic epidemiological features of AA patients in China and to determine the possible genetic model for AA.

METHODS

Data for 1032 patients with AA were obtained by questionnaire in the Institute of Dermatology of Anhui Medical University in China from 2001 to 2003. Complex segregation analysis and heritability analysis were performed using Falconer's method, EPI INFO 6.0 and SAGE-REGTL programs.

RESULTS

In total, 1032 AA patients (male/female ratio 1.1 : 1) were enrolled, representing 0.94% of the total number of cases seen in our outpatient clinic during that time. The mean +/- SD age of onset was 28.98 +/- 13.43 years. The difference between the mean age of onset in males and females was not significant. Most patients (82.6%) experienced their first episode of AA within the first four decades of life. A positive family history of AA was obtained in 87 patients (8.4%). The prevalence of AA in first-, second- and third-degree relatives of the proband with AA was 1.6%, 0.19% and 0.03%, respectively. These figures were higher than those in controls. A greater severity and longer duration of AA were seen in the early onset group than in the late-onset group. The early onset group also had more affected first- and second-degree relatives. The heritability of AA in first-, second- and third-degree relatives was 47.16%, 42.53% and 22.29%, respectively. Based on the REGTL results, the best model was a polygenic additive model for AA.

CONCLUSIONS

The effect of genetic factors is strong in AA, but environmental factors such as infection and psychological stress may still play an important role. Our findings on the genetics of AA are consistent with a polygenic additive mode of inheritance.

Alopecia areata and cytomegalovirus infection in twins: genes versus environment?

BACKGROUND

Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease mediated by T cells directed to the hair follicle. Genetic susceptibility may be conferred by HLA, and an environmental trigger, such as a viral infection, is suspected. The incidence of AA in the population is estimated to be 1.7%, with an average of one in four patients having a positive family history.

OBJECTIVE

Our purpose was to examine the concordance rate of AA among identical versus fraternal twins and the correlation between stress, cytomegalovirus (CMV) infection, and disease.

METHODS

Families with AA were solicited from dermatologists in the United States and through a Website on the Internet. HLA class 2 typing and identification of CMV early and late genes were performed by polymerase chain reaction (PCR) on genomic peripheral blood DNA. Serum antibodies for CMV were determined by enzyme-linked immunosorbent assay.

RESULTS

From 114 families, we identified 11 sets of monozygotic twins and 3 sets of dizygotic twins. The concordance rate was 55% for monozygotic twins and 0% for fraternal twins. Most identical twins were male. The severity of the AA phenotype varied and appeared most severe in the first affected twin. Five of 24 twins were CMV seropositive but CMV DNA was not detected in blood lymphocytes of any of the subjects when studied after the onset of AA. The presence of AA in twins was not correlated with evidence of CMV.

CONCLUSION

A 55% concordance rate in identical twins and AA occurring in families support a genetic component as well as possible environmental triggers that remain unknown.

Alopecia areata in Korea (1982-1994)

I clinically studied 905 patients with alopecia areata (AA) who visited the Department of Dermatology, College of Medicine, Chung Ang University, from January of 1982 to February of 1994. The purpose of the study was to evaluate the clinical manifestations and compare the effects of treatment with intralesional injection of triamcinolone acetonide suspension and immunotherapy with dinitrochlorobenzene (DNCB) or diphenylcyclopropenone (DPCP). The results were as follows: 1) The incidence of AA among all out-patients (59,970) was 1.5% (905 cases), and the ratio of males to females was 1.3:1 (512:393). 2) The age distribution showed high incidences in the third (41.8%) and fourth decades (20.0%). 3) The family history was contributory in 104 cases (11.5%). 4) The relapse rate was 17.5% (158 cases). 5) Almost half of the patients had a solitary lesion (408 cases, 46.7%). 6) The most common site of predilection was the occipital region of the scalp in both male and female patients. 7) Associated diseases were seborrheic dermatitis, atopic dermatitis, hepatitis, hypertension, open heart surgery, thyroid disease, pulmonary disease, and vitiligo in order of frequency. 8) The effect of treatment on the patients who had bald patches less than 50 cm2 was not significantly statistically different between intralesional injection of triamcinolone acetonide and immunotherapy with DNCB or DPCP. 9) In cases with bald areas more than 50 cm2, including alopecia totalis and universalis, DNCB or DPCP immunotherapy showed better therapeutic effects than did intralesional injection of triamcinolone acetonide.

Antismooth muscle and antiparietal cell antibodies in Indians with alopecia areata

BACKGROUND

Alopecia areata is suspected to be an autoimmune disease. We studied 104 consecutive patients with alopecia areata for the presence of autoantibodies and associated autoimmune diseases.

METHODS

A detailed history and examination was carried out in all patients to look for associated atopy, diabetes mellitus, hypertension, rheumatoid arthritis, vitiligo, lupus erythematosus, and thyroid disorders, etc. in the patients or their family members. Venous blood for estimation of fasting and postprandial blood glucose was collected in 30 patients, especially in those with family history of diabetes mellitus. Antimitochondrial (AMA), antismooth muscle (SMA), antinuclear antibodies (ANA), antiparietal cell antibody (PCA), and antibody against thyroid microsome (TMA) were detected employing indirect immunofluorescence on a composite section of rat liver, stomach, kidney, and human thyroid. Skin biopsy was processed for direct immunofluorescence by a conventional technique.

RESULTS

Disseminated discoid lupus erythematosus, lichen planus, urticaria, psoriasis, and seronegative spondylarthritis were associated with alopecia areata in one case each. Antismooth-muscle-antibodies and PCA were found in 36 (34.6%) and 44 (42.3%) patients respectively, followed by TMA in 8 (7.7%), AMA in 6 (5.7%), antithyroglobulin antibodies in 3 (2.8%), and ANA in 2 (1.9%) patients. The incidence of SMA was higher in men with alopecia areata (P < 0.001). Direct immunofluorescence carried out in 24 patients did not reveal significant findings, except for occasional immunoglobulin deposits around hair follicles and blood vessels.

CONCLUSION

Alopecia areata in India is associated more often with antismooth muscle and antiparietal cell antibodies.

Prevalence of thyroid diseases in patients with alopecia areata

BACKGROUND

The prevalence of thyroid disease in patients with alopecia areata previously reported varied from 0 to 28%. These thyroid diseases, include Hashimoto's thyroiditis, Graves' disease, simple goiter, and others.

METHODS

The prevalence of thyroid diseases was determined in 152 consecutive patients with alopecia areata who presented to the dermatology clinic. A complete history was taken and a physical examination was performed. Thyroxine, triiodothyronine, thyroid-stimulating hormone, and microsomal antibody levels were measured in every patient. The control group consisted of 152 age- and sex-matched volunteers who had skin diseases other than alopecia areata or autoimmune disorders.

RESULTS

Among 152 patients, age 10-59 years, four cases (2.6%) had a small simple goiter. Microsomal antibodies were detected in seven other patients (4.6%) with titers ranging from 1:100 to 1:1600. None of these seven patients had signs or symptoms of thyroid disease. Five cases (3.3%) of the control group had positive microsomal antibody tests with titers ranging from 1:100 to 1:400. The prevalence of positive microsomal antibodies in the alopecia areata group was not statistically different from the control group (chi 2 = 0.347, DF = 1, P = 0.5558).

CONCLUSIONS

Among 152 patients with alopecia areata, 4.6% of patients had microsomal antibodies and 2.6% had a small simple goiter. Thus the prevalence of thyroid disease among these patients was 7.2%. The prevalence of positive microsomal antibodies in 4.6% of the patients was not statistically different from that of the control group.

Immunohistological study of the development of the cellular infiltrate in the pelage follicles of the DEBR model for alopecia areata

The Dundee experimental bald rat (DEBR) undergoes hair loss associated with perifollicular infiltrates of mononuclear cells (MNC), a pathological characteristic of human alopecia areata (AA). To investigate further the pathogenesis of the disease in this animal model, we have studied the development, composition and extent of the perifollicular MNC infiltration in young (6-week-old), prelesional (3-month-old), active lesional, and established lesional DEBR rats, using 6-week- and 6-month-old Wistar rats as normal controls. The proportions of hair follicles showing infiltration by MNC and their main subsets were determined using immunohistochemical staining of serial cryostat sections of flank skin biopsies. There was a good correlation between the degree of leucocyte (OX-1+) infiltration of anagen hair follicles and the development of hair loss. In 6-week-old DEBR skin, there were few perifollicular cells expressing MHC class II, with positively stained dendritic cells in the dermis above the sebaceous gland. There was a sparse perifollicular distribution of CD4+ cells (W3/25) and macrophages (ED-1+). No CD8+ cells (OX-8+) were seen associated with DEBR hair follicles, and only small numbers were present in Wistar rats. In prelesional DEBR rats there was an increased perifollicular presence of MHC class II+ cells, macrophages, and particularly of CD8+ cells, with little change in CD4+ cells. Active and established lesional rats, i.e. animals with overt loss of hair, showed a significant increase in the degree of MNC infiltration and the proportion of infiltrated follicles, the majority of which were in dystrophic anagen. In the perifollicular infiltrate the CD4+:CD8+ ratio was approximately 2:1. An intrafollicular infiltrate was prominent, and was composed of CD8+ cells and macrophages, with bulbar and suprabulbar keratinocytes expressing MHC class II antigens. CD4+ cells were not detected in follicular epithelium. ICAM-1 expression correlated with MNC infiltration. These results show marked similarities to lesional human AA. They also focus on a possible active role for CD8+ cells in the pathogenesis of hair loss in the DEBR rat.

Profile of alopecia areata: a questionnaire analysis of patient and family

Eight hundred patients with alopecia areata (AA) responded to a detailed questionnaire that was compiled, distributed, and analyzed by Help Alopecia International Research, Inc. (HAIR). Among those responding, 28% were men and 72% were women. Fifty percent had localized alopecia, 30% had alopecia totalis, and 20% had alopecia universalis. Forty-eight percent developed their initial onset before the age of 20. A very strong family history of 42% was found. There were 333 additional family members with AA. Many patients and relatives had concurrent atopic diseases (seasonal rhinitis, bronchial asthma, and atopic dermatitis). Associated autoimmune diseases including vitiligo, thyroid disease, and collagen vascular disease in patients and relatives appeared consistent with previous reports. Insulin dependent diabetes mellitus (IDDM) was not increased in patients but greatly increased in relatives. Additional analysis suggests a genetic association between the two diseases where expression of AA may prevent the development of IDDM.

Failure of passive transfer of serum from patients with alopecia areata and alopecia universalis to inhibit hair growth in transplants of human scalp skin grafted on to nude mice

We have previously demonstrated regrowth of hair in scalp skin grafts taken from patients with alopecia areata (AA) and alopecia universalis (AU) following engraftment on to nude mice. This present study was to determine whether serum from patients with AA and AU, has a role in the process of hair loss and the role of antibodies and complement. Forty mice were grafted with transplants obtained from seven patients. One group of the grafted mice was given patients' serum and another group normal serum. The mice were treated topically with cyclosporin (CyA), or olive oil. Hair growth was noted in most grafts and intravenous injections of serum did not prevent or inhibit this process. Immunofluorescence studies before grafting showed deposition of immunoglobulins and complement in hair follicles in both normal and affected scalp skin, but a more striking deposition was noted in the affected skin. Deposition of immunoreactants after grafting was observed only after the injection of serum from the patients but not with normal serum. Thus the sera from patients with AA or AU, when injected into nude mice with hair transplants from the scalp skin of patients with these disorders, does not alter the hair growth despite deposition of immunoreactants around the hair follicles.

Alopecia areata and associated diseases in Saudi patients

Alopecia areata is a common presentation of Saudi patients seen at dermatology clinics. Although autoimmune factors have been suggested as pathogenic factors, alopecia areata remains a disease of unknown etiology. We investigated 92 patients with alopecia areata as compared to 88 sex- and age-matched healthy control subjects for the prevalence of associated diseases as well as abnormalities of thyroid function, and for the frequency of anti-thyroid antibodies. We found that atopy and pscychological stress constitute the most commonly associated disorders in our series. Except for two female patients with diabetes mellitus, none of the remaining patients displayed clinical evidence of endocrine or autoimmune disease. Only one patient had high T(3) and T(4) values and five (5.4%) had low titers of anti-thyroid antibodies, an acceptable finding for the normal population.

Alopecia areata, endocrine function, and autoantibodies in patients 16 years of age or younger

Forty-five children with alopecia areata were prospectively studied by means of both clinical and laboratory evaluation for evidence of endocrine diseases and autoantibodies. Twenty-four percent had an abnormality as determined by one or more thyroid function studies (thyroxine, triiodothyronine, and thyroid-stimulating hormone) and/or elevation of microsomal antibody levels. In 16%, smooth muscle antibody was present, and in 4%, parietal cell antibody was present. Routine thyroid function testing is recommended for all children with alopecia areata.

Hair loss. Common congenital and acquired causes

Hair loss is a common problem likely to be encountered by a clinical practitioner. The most frequent causes of hair loss in pediatric patients include tinea capitis, alopecia areata, traction alopecia, and trichotillomania. In the adult population, causes to be considered are alopecia areata and hair loss associated with systemic disease and hormonal influence. The clinician must be able to separate the types and causes of hair loss into those that reflect primary dermatologic conditions and those that represent reaction to systemic disease.

Tissue-specific autoantibodies and autoimmune disorders in vitiligo and alopecia areata: a retrospective study

We retrospectively analyzed our laboratory reports of tissue-specific autoantibodies (TSA) in 38 patients with alopecia areata (AA) and 31 patients with vitiligo. These reports were based on standard indirect immunofluorescence (IF) procedures, employing monkey tissues as substrates. One or more TSA were detected in 39% of serum samples. Thyroid (microsomal and/or thyroglobulin) antibodies had the highest occurrence rate and, as compared with the normal population, were detected at a greater frequency in both vitiligo and AA. Over half (58%) of our patients with vitiligo had one or more detectable TSA, while only 28% of patients with AA had such antibodies. When compared with the normal population, the occurrence rate of TSA was higher in patients with vitiligo. The only remarkable finding in AA was a higher than normal occurrence rate of antithyroid antibodies.

Alopecia areata: pathogenesis and treatment

Although its etiology remains unknown, evidence has accumulated to support an autoimmune pathogenesis for alopecia areata. Our review summarizes the immunologic data and also examines the role of genetics, atopy, and psychologic stress in this disorder. Until etiology is better understood, treatments for alopecia areata are likely to remain palliative. Nevertheless, newer therapies such as photochemotherapy, topical immunotherapy, and perhaps systemic immunotherapy (e.g., inosiplex) offer new hope for patients with extensive disease.

Immunological profiles in alopecia areata

Cell-mediated immunity and auto-immune phenomena were investigated in sixty patients with active alopecia areata of various degrees of severity. Serum auto-antibodies to thyroid antigens were detected in twenty-three patients. Examination of T-lymphocyte populations, lymphocyte DNA synthesis, and lymphokine production in response to mitogen stimulation revealed no differences between the sixty patients and matched healthy control subjects. However, patients with thyroid auto-immunity and/or the presence of alopecia totalis or universalis showed significant reductions in interactive T lymphocytes (recognized by rosette formation with human B lymphoblastoid cells) and diminished production of leukocyte migration inhibition factor in response to stimulation with phytohaemagglutinin. This suggests that immune mechanisms may be involved in the pathogenesis of alopecia areata which is associated with thyroid auto-immunity or which progresses to total hair loss.

Suppressor cell decrease in alopecia areata

There is considerable evidence to suggest that autoimmunity plays a role in the pathogenesis of alopecia areata. Since it is known that T cells regulate the immune system, a study was undertaken to measure T helper (OKT-4) and T suppressor (OKT-8) cells in the peripheral blood of patients with alopecia areata (both active and stable) and in controls. Total T cells, B cells, immunoglobulins, and autoantibodies were also measured. There was a highly significant decrease in the T-suppressor cell population of patients with alopecia areata (P less than 0.001). Two of ten patients had microsomal antibodies and three of ten had elevated IgE levels. Other parameters were not significantly different. The decrease in suppressor cells suggest an impairment of the prime negative regulator of the immune system, with loss of tolerance and resultant autoimmunity.

Decreased lymphocyte reactivity and auto-immunity in alopecia areata

T lymphocyte numbers and functions were measured in forty-six patients with alopecia areata and thirty healthy controls. In patients with alopecia areata, lymphocyte reactivity to extracts of scalp and hair follicles was not detected by 3H thymidine incorporation. 3H Thymidine incorporation by lymphocytes cultured with PPD, Varidase and C. albicans was significantly reduced in cells from patients compared with controls and correlated with the extent of hair loss and the presence of antithyroid antibodies. Decreased lymphocyte responses to PPD and Varidase were not due to the presence of suppressor monocytes because removal of monocytes with carbonyl iron did not increase lymphocyte reactivity. However, responsiveness to C. albicans was augmented by removal of monocytes. T cell numbers were significantly lower than in controls (P less than 0.005); patients with auto-antibodies had fewer T cells than patients without them. The relationship of reduced T cell function and auto-immunity to alopecia areata is discussed.

Alopecia areata and auto-immunity

The prevalence of auto-antibodies against thyroid constituents, gastric parietal cells, smooth muscle cells, mitochondria, reticulin, nuclear constituents and rheumatoid factor in 108 patients with alopecia areata was compared with that found in a previous survey of the local population. Female patients had a significantly increased prevalence of anti-thyroid antibodies which were present in 30% overall and in 44% of the youngest age group (11-17 years). Smooth muscle antibodies were more frequent in female patients but the increase was not significant. Male patients had a significant increased prevalence of thyroid and gastric parietal cell antibodies (11.4% each). In females, antithyroid antibodies were associated with extensive hair loss: they were found in 42% of female patients with total alopecia and only 20% of males with total hair loss. A family history of alopecia areata was obtained from 24% of patients; 10% had relatives with thyroid disease and 10% had diabetic relatives. These findings confirm the association between alopecia areata and the other auto-immune diseases.

HLA and alopecia areata in Jerusalem

A study of 46 patients with Alopecia areata in Jerusalem showed a significant increase in the frequency of HLA-B18 (23.9%) as compared to the control population (7.4%) with a relative risk of 3.9%. This association of HLA-B18 with AA was independent of the origin of patients, sex, age of onset and type of alopecia areata.

Antigenic competition as a therapeutic concept for alopecia areata

Alopecia areata can be treated effectively by topical application of potent contact allergens. To explain the response, the following hypothesis is presented. Alopecia areata is considered an autoimmune disease. The characteristic peribulbar round cell infiltrates probably reflect a cell-mediated immune reaction to some hair-associated antigen. With the elicitation of contact allergy, a second antigen is introduced at the same site. The infiltrates of the allergic contact dermatitis contain suppressor T cells and suppressor macrophages which, in terms of local immunoregulation, exert a nonspecific inhibitory effect on the immune response against hair follicles. Regrowth of hair would be due to a change in the local balance between helper and suppressor cells. In conclusion, the phenomenon of antigenic competition is proposed as a therapeutic concept.