Biomarker and determination assistance method

Abstract

To provide a biomarker which is usable for determining the onset risk of acne.SOLUTION: One aspect of the present invention provides a biomarker which is usable for determining the onset risk of acne. The biomarker is type III Cutibacterium acnes.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a biomarker and a diagnosis assistance method. [Background technology]

[0002] Bacteria normally present on human skin reflect the condition of the skin and the state of disease. Cutibacterium acnes is the most prevalent bacterial species on the skin and plays a central role in the development of acne (see Non-Patent Document 1). It is preferable to be able to accurately know the risk of developing acne in advance, since this allows treatment to be started early to improve the condition of the body, such as the skin. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Beylot et al., J.Eur.Acad.Dermatol.Venereol.28,271-278 Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the above circumstances, the present invention provides a biomarker or the like that can be used to determine the risk of developing acne. [Means for solving the problem]

[0005] According to one aspect of the present invention, there is provided a biomarker that can be used to determine the risk of developing acne. This biomarker is Propionibacterium acnes type III.

[0006] According to this embodiment, it can be used to accurately determine the risk of developing acne. [Brief explanation of the drawings]

[0007] [Figure 1]1 is a graph showing the proportion of Propionibacterium acnes among all bacteria in subjects with and without acne. [Figure 2] 1 is a graph showing the proportion of acne bacteria among all bacteria by age group. [Figure 3] 1 is a graph showing the logarithmic copy number of total Propionibacterium acnes contained in a sample per 6.4 mm2 in "with acne" and "without acne." [Figure 4] 6. A graph showing the logarithmic copy number of total Propionibacterium acnes in samples per 4 mm2 by age group. [Figure 5] 1 is a graph showing the type composition of Propionibacterium acnes in all subjects. [Figure 6] 1 is a graph showing the composition of acne bacteria types by age group. DETAILED DESCRIPTION OF THE INVENTION

[0008] The biomarker and the diagnosis assistance method of the present invention will be described below. The various features shown in the following embodiments can be combined with each other.

[0009] The biomarker of the present invention can be used to determine the risk of developing acne (hereinafter also referred to as "pimples"). The biomarker of the present invention is Propionibacterium acnes type III. Here, P. acnes is genetically classified into five subclasses: types IA1, 1A2, 1B, II, and III. Studies by the present inventors have revealed that subjects who complain of acne symptoms tend to have a higher proportion of P. acnes in the total bacteria contained in samples collected from the subjects, and a lower proportion of type III P. acnes in the total bacteria, compared to subjects who do not complain of symptoms. Therefore, it is believed that the risk of developing acne can be accurately determined by using type III acne bacteria as a biomarker. When the proportion of the biomarker of the present invention (type III acne bacteria) in the total acne bacteria contained in a sample (hereinafter also simply referred to as "sample") collected from a subject is within a predetermined range, it can be used to determine whether the subject is at high risk of developing acne. The specific value of the predetermined range is preferably less than 2%, more preferably less than 1.5%, and even more preferably 0.1% or more but less than 1%. In this way, subjects with a low ratio of biomarkers can be determined to have a high probability of developing acne.

[0010] If the ratio of the biomarkers is within the above range and the ratio of all P. acnes to all bacteria contained in the sample is within a predetermined range, it can be used to determine that the risk of developing acne is high, thereby further increasing the accuracy of the determination. The specific value of the predetermined range is preferably 45% or more, more preferably 45% to 70% or less, and even more preferably 50% to 65% or less. Thus, subjects whose biomarker ratios are within the above ranges and whose total P. acnes ratio is high can be determined to have a higher probability of developing acne.

[0011] In addition, the ratio of biomarkers is within the above range, and further, 6.4 mm 2 When the logarithmic copy number of all P. acnes contained in a sample per day is within a predetermined range, it can be used to determine a high risk of developing acne. This can further increase the accuracy of the above determination. Note that in this specification, logarithm refers to a common logarithm with a base of "10." The specific value of the predetermined range is preferably 3.75 or more, more preferably 3.9 to 4.5, and even more preferably 4.05 to 4.3. Thus, subjects whose biomarker ratios are within the above ranges and whose logarithmic copy numbers of all P. acnes bacteria are high can be determined to have a higher probability of developing acne.

[0012] The site from which a sample is taken from a subject is not particularly limited, and examples thereof include any site that comes into contact with the external environment, such as the skin, digestive tract, oral cavity, nasal cavity, respiratory tract, and genital tract. Among these, the site from which a sample is taken is preferably the subject's skin. If the sample is taken from the subject's skin, it is easy to take a sample suitable for determining the risk of developing acne. The skin may be taken from any part of the body, but is preferably at least one of the forehead, cheeks, chin, nose, and neck, and more preferably the forehead, as samples taken from these areas can provide results that more accurately reflect the risk of developing acne.

[0013] The assessment assistance method of the present invention is a method for assisting in assessing the risk of developing acne. Such a judgment assistance method includes an identification step and a specification step. Each step will be explained below in order.

[0014] <Identification process> In the identification step, all species and types of bacteria contained in the sample collected from the subject are identified. Preferred sites for collection of samples from subjects are as described above. Samples can be collected, for example, by attaching an adhesive (adhesive patch, adhesive sheet, etc.) to the collection site and transferring the sample to the adhesive layer, or by wiping the surface of the collection site with a cotton swab. Although various methods utilizing lipase or genetic characteristics can be used to identify the species and types of all bacteria contained in a sample, it is preferable to combine a microbiome analysis method based on the 16S rRNA gene with a subtype structure analysis method based on a gene of Propionibacterium acnes. Using such a method, all species and types of bacteria can be accurately identified.

[0015] <Specific process> In the identification step, the proportion of type III acne bacteria in all acne bacteria is identified. This can be obtained by dividing the number of type III acne bacteria by the total number of acne bacteria based on the results of the total bacterial species and types identified in the identification step. Note that the proportion of type III acne bacteria may be a result obtained from a sample collected from one collection site, or may be an average value of results obtained from samples collected from multiple collection sites. If the proportion is less than 2% (preferably less than 1.5%, more preferably 0.1% to less than 1%), it is preferable to determine that the risk of developing acne is high, taking into consideration the subject's medical history, skin photographs, etc. In other words, if the proportion of type III acne bacteria in all acne bacteria is less than 2%, this can help determine that the risk of developing acne is high.

[0016] In the identification step, it is preferable to further identify whether the proportion of all P. acnes bacteria in all bacteria is 45% or more (preferably 45% to 70%, more preferably 50% to 65%). In this case, it is possible to more accurately determine whether the risk of developing acne is high. In addition, in the specific process, 6.4 mm 2 It is also preferable to determine whether the log copy number of all Propionibacterium acnes contained in the sample per sample is 3.75 or more (preferably 3.9 to 4.5, more preferably 4.05 to 4.3). This also helps to more accurately determine whether the risk of developing acne is high.

[0017] The biomarkers and assessment assistance methods of the present invention as described above enable accurate assessment of the risk of developing acne, which has the advantage of allowing treatment to be started early to improve the condition of the body, such as the skin. Furthermore, it may be provided in the following aspects.

[0018] (1) A biomarker that can be used to determine the risk of developing acne, which is type III acne bacteria.

[0019] (2) The biomarker described in (1) above, which is used to determine that a subject is at high risk of developing acne when the proportion of the biomarker in the total acne bacteria contained in a sample collected from the subject is less than 2%.

[0020] (3) The biomarker according to (2) above, further used to determine that the risk of developing acne is high when the proportion of the total Propionibacterium acnes in the total bacteria contained in the sample is 45% or more.

[0021] (4) The biomarker according to (2) or (3) above, further comprising: 2 The biomarker is used to determine that the risk of developing acne is high when the log copy number of all Propionibacterium acnes contained in the sample per sample is 3.75 or more.

[0022] (5) The biomarker according to any one of (2) to (4) above, wherein the sample collection site is the skin of the subject.

[0023] (6) The biomarker described in (5) above, wherein the skin is at least one of the forehead, cheek, chin, nose, and neck.

[0024] (7) A method for assisting in determining the risk of developing acne, comprising an identification step and a specification step, wherein the identification step identifies the species and types of all bacteria contained in a sample collected from a subject, and the specification step specifies the proportion of type III acne bacteria among all acne bacteria.

[0025] (8) The method according to (7) above, wherein the method assists in determining that the risk of developing acne is high when the proportion of the type III acne bacteria in the total acne bacteria is less than 2% in the identifying step.

[0026] (9) The method according to (8) above, wherein the step of identifying further includes identifying whether the proportion of all acne bacteria in the total bacteria is 45% or more.

[0027] (10) In the method according to (8) or (9) above, in the specifying step, 6.4 mm 2 The method also determines whether the log copy number of the total Propionibacterium acnes contained in the sample per sample is 3.75 or greater. Of course, this is not the case.

[0028] As described above, various embodiments of the present invention have been described, but these are presented as examples and do not limit the scope of the invention in any way. The novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Such embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as set forth in the claims. [Example]

[0029] The present invention will be explained in more detail below by way of examples, but the present invention is not limited to these examples.

[0030] First, a total of 296 Japanese women in their 20s to 40s were enrolled as subjects. The average age was 36.0 years old. Of the enrolled subjects, 219 subjects complained of acne symptoms (hereinafter referred to as "with acne"), with an average age of 34.7 years old, and 77 subjects did not complain of acne symptoms (hereinafter referred to as "without acne"), with an average age of 40.3 years old. Table 1 below shows the percentage of people with and without acne by age group.

[0031] [Table 1]

[0032] Facial skin conditions were obtained from these subjects using an online questionnaire and smartphone photos. At the same time, a skin surface sample was taken using an adhesive patch ("MySkin" manufactured by TAK-Circulator Co., Ltd.) and mailed directly to the subjects. For subjects without acne, samples were taken from the skin surface of the cheek, and for subjects with acne, samples were taken from the skin surface of areas with acne (cheeks, forehead, chin, around the mouth). For each sample, microbiome analysis based on the 16S rRNA gene and type structure analysis based on a single gene of Propionibacterium acnes were performed.

[0033] Quality checks after DNA extraction were passed for all samples. The percentage of Propionibacterium acnes among all bacteria in the "with acne" and "without acne" groups is shown in Table 2 below and Figure 1. Figure 1 is a graph showing the percentage of Propionibacterium acnes among all bacteria in the "with acne" and "without acne" groups. As a result, the proportion of acne bacteria among all bacteria was 51.7% in those with acne and 44.3% in those without acne, which was significantly higher in those with acne than in those without acne (p<0.05).

[0034] [Table 2]

[0035] The percentage of Propionibacterium acnes among all bacteria is shown by age group in Table 3 below and Figure 2. Figure 2 is a graph showing the percentage of Propionibacterium acnes among all bacteria by age group. The results showed that the proportion of acne bacteria among all bacteria was lower in older age groups, consistent with previous reports. There was also a significant difference (p<0.05) between people in their 20s and 40s.

[0036] [Table 3]

[0037] Table 4 and Figure 3 below show the results for "with acne" and "without acne" at 6.4 mm 2 Figure 3 shows the logarithmic copy number of all P. acnes in the samples per 6.4 mm in the "with acne" and "without acne" groups. 2 1 is a graph showing the log copy number of total P. acnes in samples per 100 ml. As a result, the logarithmic copy number of all acne bacteria was 4.117 in "with acne" and 3.722 in "without acne," which was significantly higher in "with acne" than in "without acne" (p<0.001).

[0038] [Table 4]

[0039] In addition, in Table 5 and Figure 4 below, 2 Figure 4 shows the logarithmic copy number of all P. acnes in samples per year. 2 1 is a graph showing the logarithmic copy number of total Propionibacterium acnes in samples per year by age group. As a result, the logarithmic copy number of all P. acnes strains was lower in older age groups, consistent with previous reports. There was also a significant difference (p<0.05) between those in their 20s and 30s, and between those in their 20s and 40s.

[0040] [Table 5]

[0041] Next, the makeup of the types of Propionibacterium acnes in all subjects is shown in Figure 5. Figure 5 is a graph showing the makeup of the types of Propionibacterium acnes in all subjects. The results showed that type IA1 was the most common at 42.8%, followed by type IA2 at 24.5%, type II at 21.5%, type IB at 10.1%, and type III at 1.1%.

[0042] The types of acne bacteria in the subjects are shown by age in the following Tables 6 to 10 and Figure 11. Figure 11 is a graph showing the types of acne bacteria in the subjects by age. As a result, the composition of acne bacteria types was similar across all age groups.

[0043] [Table 6]

[0044] [Table 7]

[0045] [Table 8]

[0046] [Table 9]

[0047] [Table 10]

[0048] Next, the following Tables 11 to 15 show a comparison of the proportions of each subtype between those with "acne" and those without "acne." As a result, the proportion of each type was 2.5% for "with acne" and 0.6% for "without acne" in the case of type III acne bacteria, with "with acne" being significantly higher than "without acne" (p<0.01).

[0049] [Table 11]

[0050] [Table 12]

[0051] [Table 13]

[0052] [Table 14]

[0053] [Table 15]

[0054] Based on the above results, type III P. acnes is suitable for use as a biomarker for determining the risk of developing acne. [Explanation of symbols]

[0055] IA1: Type IA1 IA2: Type IA2 IB: Type IB II: Type II III: Type III

Claims

1. A biomarker that can be used to determine the risk of developing acne, A biomarker for type III acne bacteria.

2. The biomarker of claim 1, A biomarker used to determine that a subject is at high risk of developing acne when the proportion of said biomarker in all acne bacteria contained in a sample collected from said subject is less than 2%.

3. The biomarker of claim 2, Furthermore, the biomarker is used to determine that the risk of developing acne is high when the proportion of all P. acnes bacteria in all bacteria contained in the sample is 45% or more.

4. The biomarker of claim 2, Furthermore, 6.4 mm ２ The biomarker is used to determine that the risk of developing acne is high if the log copy number of all Propionibacterium acnes contained in the sample per sample is 3.75 or more.

5. The biomarker of claim 2, A biomarker, wherein the sample collection site is the skin of the subject.

6. The biomarker according to claim 5, The skin is at least one of the forehead, cheek, chin, nose, and neck.

7. A method for assisting in determining the risk of developing acne, comprising: The method includes an identification step and a specification step, In the identification step, all species and types of bacteria contained in the sample collected from the subject are identified; The method of claim 1, wherein the identifying step identifies a proportion of type III acne bacteria in all acne bacteria.

8. 8. The method of claim 7, The method further comprises assisting in determining that the risk of developing acne is high when the proportion of the type III acne bacteria in the total acne bacteria is less than 2% in the identifying step.

9. 9. The method of claim 8, The method further comprises determining whether the proportion of all acne bacteria in the total bacteria is 45% or more in the identifying step.

10. 9. The method of claim 8, In the specifying step, 6.4 mm ２ The method also determines whether the log copy number of the total Propionibacterium acnes contained in the sample per sample is 3.75 or greater.

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