1. In the earliest work, vibrissae derived DPs were transplanted into micro-incision of ear skin.
7 days after the following structures were founded at histology: big vibrissae derived DPs were surrounded by epithelial roots. Some of these roots originate from local pelage HFs, others from interfollicular epidermis. No HF neogenesis was noticed.
4 weeks after transplantation no big vibrissae derived DPs were founded. And the only HFs founded in ear skin were local pelage HFs [some of them were with invert orientation]. From this it was concluded that interfollicular E and dermal fibroblasts exert specific inductive influence on transplanted DPs. As a result of this influence, vibrissae derived DPs shrink in their sizes [due to the lost of fibroblasts], their volume become equal to the volume of DPs of local DPs from pelage HFs. At the same time vibrissae derived DPs interact with local interfollicular E and thy form together new HFs of local pelage type.

J. COHEN. The transplantation of individual rat & guinea-pig whisker papillae . // J. Embryol. exp. Morph. Vol. 9 , part 1 , p. 177-127 . 1961

One should be very cautious while estimating these results. Here author propose unrealistic scenario of morphogenic process, were the leading role is played not by DP but local environment of recipient tissue of ear skin.
In all following experiments these results were refused.

2. Thereafter the following operation technique was utilized: semi-thickness piece of ear skin was cut off. Vibrissae derived DPs were than transplanted onto derma. Above them epidermis from 2 body regions: from ear pinna, from scrotum and epithelium from oral cavity were transplanted. This complex system was covered at the end by semi-thickness piece of ear skin.
In case of ear epidermis, 14 days after operation HFs’ matrix-like structure was identified. 28 days after transplantation structures closely resembling HFs were founded. First fibre production by these structures was noticed 35 days after operation. New HF were undoubtedly much larger than local pelage HFs, their ORS has more than 3 [up to 6] layers of cells. But they morphology was highly defective in comparison with intact vibrissae HFs.
In association with scrotal epidermis transplanted DPs form new HFs 35 days after transplantation. Yet they morphology was also highly defective.
It is interesting, but structures that are formed 35 days after operation by vibrissae derived DPs and oral epithelium, according to authors interpretation, have signs of HFs. They are ORS and IRS. Nevertheless, fiber production was not noticed. Even the most curious is the authors conclusion, that one of this structure resemble developing enamel organ. But it should be noted, that at histology closely adjoined to this structure a local pelage HF was founded. Therefore, it is more than probable, that it was its cells, that have token part in this morphogenic process.

R. F. OLIVER The dermal papilla & the development & growth of hair. // J. Soc. Cosmet. Chem. 22 . p. 741- 755 . 1971.
R.F. OLIVER., The induction of hair follicle formation in the adult hooded rat by vibrissa dermal papillae. // J. Embriol. Exp. Morph., vol.23., p.219-236., 1970
C. A.OLIVER Local interactions in mammalian hair growth. "Skin Vertebr. Pap. Symp., London 1978". p.199 –210., 1980

3. Cultured vibrissae DP fibroblasts were transplanted according to Cohen technique into micro-incision of ear skin. Several days later at histology it was founded that transplanted DPs interact with interfollicular E of incision edges . as a result of this interaction new, giant, vibrissa-like HF were induced.

C. A. JAHODA., F. J. REYNOLDS. Inductive properties of hair follicle cells. // 1991 Annals of the New York academy of sciences . vol 642, p227-242
R.F. OLIVER., C. A. JAHODA., HORNE K.A., Whisker growth induced by implantation of cultured vibrissa dermal papilla cells in the adult rat. // J. Embryol. exp. Morph. Vol.97., p.111-124., 1986

4. Afterwards, more perfect experimental system was introduced. On 10 days old granulation tissue a piece of paw skin was transplanted. Small pellets of cultured DP fibroblasts from pelage HFs were implanted between epidermis and derma of paw skin. This system was protected from tissue invasion from wound edges by silicon chamber. 8 weeks after transplantation at histology 5 from 6 implants induce new HFs and 50 % of them [i.e. 3 DP cells implants] induced new HFs that produce visible fibres. Fibres in average were 8 mm long. They morphology was closer to pelage fibers. Morphologically new HFs were highly structured, but they do not have sebaceous glands. It is strange, but induced HFs were pigmented. Paw epidermis wasn’t pigmented. Therefore, the most probable source of active melanocytes was a not pure culture of DP fibroblasts. Dermal fibroblasts [they were used for negative], when transplanted instead DP cells don’t induce new HFs.

C. A. JAHODA., F. J. REYNOLDS. Inductive properties of hair follicle cells. // 1991 Annals of the New York academy of sciences . vol 642, p227-242
C. A. JAHODA., F. J. REYNOLDS Cultured dermal papilla cells induce follicle formation & hair growth by transdifferentiation of an adult epidermis. // Development., vol.115(2)., p.587-593., 1992

5. Analogous results were achieved in case of vibrissae derived DP fibroblasts.

JAHODA CA., REYNOLDS AJ ., Dermal- epidermal interaction . Follicle derived cell populations in the study of hair growth mechanism . // J. Invest. Dermatol. 1993 vol. 101 p. 33s-38s

6. In a series of experiments inductive influence of low- and high-passage vibrissae HF derived DP fibroblasts on E was studied:
Low-passage DP fibroblasts, when transplanted into micro-incision of ear skin, repeatedly induce new HFs, that produce thick fibres. Histologically these HFs have signs of intact vibrissae HFs. When these low-passage DP fibroblasts were transplanted, wrapped in E from afollicular skin into micro-incision of ear skin they also induce new, vibrissae-like HFs. But this follicular neogenesis took part less frequently.
High-passage DP cells as well as dermal fibroblasts in thee experimental conditions weren’t capable to induce follicular neogenesis.

R.F. OLIVER., C. A. JAHODA., REYNOLDS AJ ., induction of hair growth in ear wound by cultured dermal papilla cells. // J. Invest. Dermatol., vol.101(4)., p.584- 590., 1993

7. These result were confirmed by experiments, where cultured basal keratinocytes and high-passage DP cells were transplanted together into ear skin’s micro-incision. No HFs were induced in this case.

C. A. JAHODA., F. J. REYNOLDS ., Hair matrix germinative epidermal cells confer follicle-inducing capabilities on dermal sheath & high passage papilla cells. // Development., vol.122(10)., p.3085-3094., 1996

8. Vibrissae HF derived DPs of postnatal rats were isolated and transplanted between epidermis and derma of 14 days old mouse embryos [at this stage HFs formation is just initiated]. Thereafter this systems were transplanted to nude mice. 21-42 days thereafter pelage HFs densely covered skin of mice-donors. At the same time transplanted vibrissae DPs in 37 % induced bigger HFs. They have defective, asymmetrical morphology, in 100 % collagen capsule and blood sinuses were absent.
Adult human cultured breast E cells and full-thickness wound healing from human facial skin and foreskin were associated with either rabbit embryonic trichogenic dermis or cultured DPs cells of adult rat, before grafting onto nude mice for 2 weeks to 1 month [in situ hybridization with a human specific sequence Alu probe labeled the human cells, whereas implanted rabbit or rat and host mouse cells were distinguished by the Hoechst staining of their nuclei]. The results show that human adult cultured breast E cells are able to form hair buds and to participate in HF formation, while adult healing E from a sparsely hairy skin as the human face or the dorsal skin of nude mouse, or even from a glabrous E as the human foreskin, are able to differentiate pilosebaceous units. Although a follicular origin of the involved keratinocytes cannot be excluded in the three first cases, the formation of HFs and sebaceous glands by foreskin keratinocytes of children 2 to 10 years-old establishes the cutaneous appendage ability of the interfollicular E stem cells. The formation of interspecies mosaic Hfs also highlights the fact that there must be a significant level of commonality in the interactive signaling molecules used by epithelial cells from different species.

FERRARIS C., BERNARD B.A., DHOUAILLY D., Adult epidermal keratinocytes are endowed with pillosebaceous forming abilities. // Int. J. Dev. Biol., vol.41(3)., p.491-498., 1997